Project import
diff --git a/libpng/ANNOUNCE b/libpng/ANNOUNCE
new file mode 100644
index 0000000..4dae783
--- /dev/null
+++ b/libpng/ANNOUNCE
@@ -0,0 +1,52 @@
+Libpng 1.6.20 - December 3, 2015
+
+This is a public release of libpng, intended for use in production codes.
+
+Files available for download:
+
+Source files with LF line endings (for Unix/Linux) and with a
+"configure" script
+
+ libpng-1.6.20.tar.xz (LZMA-compressed, recommended)
+ libpng-1.6.20.tar.gz
+
+Source files with CRLF line endings (for Windows), without the
+"configure" script
+
+ /scratch/glennrp/Libpng16/lpng1620.7z (LZMA-compressed, recommended)
+ /scratch/glennrp/Libpng16/lpng1620.zip
+
+Other information:
+
+ libpng-1.6.20-README.txt
+ libpng-1.6.20-LICENSE.txt
+ libpng-1.6.20-*.asc (armored detached GPG signatures)
+
+Changes since the last public release (1.6.19):
+ Avoid potential pointer overflow/underflow in png_handle_sPLT() and
+ png_handle_pCAL() (Bug report by John Regehr).
+ Fixed incorrect implementation of png_set_PLTE() that uses png_ptr
+ not info_ptr, that left png_set_PLTE() open to the CVE-2015-8126
+ vulnerability.
+ Backported tests from libpng-1.7.0beta69.
+ Fixed an error in handling of bad zlib CMINFO field in pngfix, found by
+ American Fuzzy Lop, reported by Brian Carpenter. inflate() doesn't
+ immediately fault a bad CMINFO field; instead a 'too far back' error
+ happens later (at least some times). pngfix failed to limit CMINFO to
+ the allowed values but then assumed that window_bits was in range,
+ triggering an assert. The bug is mostly harmless; the PNG file cannot
+ be fixed.
+ In libpng 1.6 zlib initialization was changed to use the window size
+ in the zlib stream, not a fixed value. This causes some invalid images,
+ where CINFO is too large, to display 'correctly' if the rest of the
+ data is valid. This provides a workaround for zlib versions where the
+ error arises (ones that support the API change to use the window size
+ in the stream).
+
+Send comments/corrections/commendations to png-mng-implement at lists.sf.net
+(subscription required; visit
+https://lists.sourceforge.net/lists/listinfo/png-mng-implement
+to subscribe)
+or to glennrp at users.sourceforge.net
+
+Glenn R-P
diff --git a/libpng/Android.mk b/libpng/Android.mk
new file mode 100644
index 0000000..959b73c
--- /dev/null
+++ b/libpng/Android.mk
@@ -0,0 +1,98 @@
+LOCAL_PATH:= $(call my-dir)
+
+# We need to build this for both the device (as a shared library)
+# and the host (as a static library for tools to use).
+
+common_SRC_FILES := \
+ png.c \
+ pngerror.c \
+ pngget.c \
+ pngmem.c \
+ pngpread.c \
+ pngread.c \
+ pngrio.c \
+ pngrtran.c \
+ pngrutil.c \
+ pngset.c \
+ pngtrans.c \
+ pngwio.c \
+ pngwrite.c \
+ pngwtran.c \
+ pngwutil.c \
+
+ifeq ($(ARCH_ARM_HAVE_NEON),true)
+my_cflags_arm := -DPNG_ARM_NEON_OPT=2
+endif
+
+my_cflags_arm64 := -DPNG_ARM_NEON_OPT=2
+
+# BUG: http://llvm.org/PR19472 - SLP vectorization (on ARM at least) crashes
+# when we can't lower a vectorized bswap.
+my_cflags_arm += -fno-slp-vectorize
+
+my_src_files_arm := \
+ arm/arm_init.c \
+ arm/filter_neon.S \
+ arm/filter_neon_intrinsics.c
+
+
+common_CFLAGS := -std=gnu89 #-fvisibility=hidden ## -fomit-frame-pointer
+
+# For the host
+# =====================================================
+
+include $(CLEAR_VARS)
+LOCAL_SRC_FILES := $(common_SRC_FILES)
+LOCAL_CFLAGS += $(common_CFLAGS)
+LOCAL_ASFLAGS += $(common_ASFLAGS)
+LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)
+LOCAL_STATIC_LIBRARIES := libz
+LOCAL_MODULE:= libpng
+include $(BUILD_HOST_STATIC_LIBRARY)
+
+
+# For the device (static)
+# =====================================================
+
+include $(CLEAR_VARS)
+LOCAL_CLANG := true
+LOCAL_SRC_FILES := $(common_SRC_FILES)
+LOCAL_CFLAGS += $(common_CFLAGS) -ftrapv
+LOCAL_CFLAGS_arm := $(my_cflags_arm)
+LOCAL_ASFLAGS += $(common_ASFLAGS)
+LOCAL_SRC_FILES_arm := $(my_src_files_arm)
+LOCAL_CFLAGS_arm64 := $(my_cflags_arm64)
+LOCAL_SRC_FILES_arm64 := $(my_src_files_arm)
+LOCAL_ADDRESS_SANITIZER := false
+LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)
+LOCAL_SHARED_LIBRARIES := libz
+LOCAL_MODULE:= libpng
+include $(BUILD_STATIC_LIBRARY)
+
+# For the device (shared)
+# =====================================================
+
+include $(CLEAR_VARS)
+LOCAL_CLANG := true
+LOCAL_SRC_FILES := $(common_SRC_FILES)
+LOCAL_CFLAGS += $(common_CFLAGS) -ftrapv
+LOCAL_CFLAGS_arm := $(my_cflags_arm)
+LOCAL_ASFLAGS += $(common_ASFLAGS)
+LOCAL_SRC_FILES_arm := $(my_src_files_arm)
+LOCAL_CFLAGS_arm64 := $(my_cflags_arm64)
+LOCAL_SRC_FILES_arm64 := $(my_src_files_arm)
+LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)
+LOCAL_SHARED_LIBRARIES := libz
+LOCAL_MODULE:= libpng
+include $(BUILD_SHARED_LIBRARY)
+
+# For testing
+# =====================================================
+
+include $(CLEAR_VARS)
+LOCAL_CLANG := true
+LOCAL_SRC_FILES:= pngtest.c
+LOCAL_MODULE := pngtest
+LOCAL_SHARED_LIBRARIES:= libpng libz
+LOCAL_MODULE_TAGS := debug
+include $(BUILD_EXECUTABLE)
diff --git a/libpng/CHANGES b/libpng/CHANGES
new file mode 100644
index 0000000..28094fd
--- /dev/null
+++ b/libpng/CHANGES
@@ -0,0 +1,5456 @@
+#if 0
+CHANGES - changes for libpng
+
+version 0.1 [March 29, 1995]
+ initial work-in-progress release
+
+version 0.2 [April 1, 1995]
+ added reader into png.h
+ fixed small problems in stub file
+
+version 0.3 [April 8, 1995]
+ added pull reader
+ split up pngwrite.c to several files
+ added pnglib.txt
+ added example.c
+ cleaned up writer, adding a few new transformations
+ fixed some bugs in writer
+ interfaced with zlib 0.5
+ added K&R support
+ added check for 64 KB blocks for 16 bit machines
+
+version 0.4 [April 26, 1995]
+ cleaned up code and commented code
+ simplified time handling into png_time
+ created png_color_16 and png_color_8 to handle color needs
+ cleaned up color type defines
+ fixed various bugs
+ made various names more consistent
+ interfaced with zlib 0.71
+ cleaned up zTXt reader and writer (using zlib's Reset functions)
+ split transformations into pngrtran.c and pngwtran.c
+
+version 0.5 [April 30, 1995]
+ interfaced with zlib 0.8
+ fixed many reading and writing bugs
+ saved using 3 spaces instead of tabs
+
+version 0.6 [May 1, 1995]
+ first beta release
+ added png_large_malloc() and png_large_free()
+ added png_size_t
+ cleaned up some compiler warnings
+ added png_start_read_image()
+
+version 0.7 [June 24, 1995]
+ cleaned up lots of bugs
+ finished dithering and other stuff
+ added test program
+ changed name from pnglib to libpng
+
+version 0.71 [June 26, 1995]
+ changed pngtest.png for zlib 0.93
+ fixed error in libpng.txt and example.c
+
+version 0.8 [August 20, 1995]
+ cleaned up some bugs
+ added png_set_filler()
+ split up pngstub.c into pngmem.c, pngio.c, and pngerror.c
+ added #define's to remove unwanted code
+ moved png_info_init() to png.c
+ added old_size into png_realloc()
+ added functions to manually set filtering and compression info
+ changed compression parameters based on image type
+ optimized filter selection code
+ added version info
+ changed external functions passing floats to doubles (k&r problems?)
+ put all the configurable stuff in pngconf.h
+ enabled png_set_shift to work with paletted images on read
+ added png_read_update_info() - updates info structure with transformations
+
+Version 0.81 [August, 1995]
+ incorporated Tim Wegner's medium model code (thanks, Tim)
+
+Version 0.82 [September, 1995]
+ [unspecified changes]
+
+Version 0.85 [December, 1995]
+ added more medium model code (almost everything's a far)
+ added i/o, error, and memory callback functions
+ fixed some bugs (16-bit, 4-bit interlaced, etc.)
+ added first run progressive reader (barely tested)
+
+Version 0.86 [January, 1996]
+ fixed bugs
+ improved documentation
+
+Version 0.87 [January, 1996]
+ fixed medium model bugs
+ fixed other bugs introduced in 0.85 and 0.86
+ added some minor documentation
+
+Version 0.88 [January, 1996]
+ fixed progressive bugs
+ replaced tabs with spaces
+ cleaned up documentation
+ added callbacks for read/write and warning/error functions
+
+Version 0.89 [June 5, 1996]
+ Added new initialization API to make libpng work better with shared libs
+ we now have png_create_read_struct(), png_create_write_struct(),
+ png_create_info_struct(), png_destroy_read_struct(), and
+ png_destroy_write_struct() instead of the separate calls to
+ malloc and png_read_init(), png_info_init(), and png_write_init()
+ Changed warning/error callback functions to fix bug - this means you
+ should use the new initialization API if you were using the old
+ png_set_message_fn() calls, and that the old API no longer exists
+ so that people are aware that they need to change their code
+ Changed filter selection API to allow selection of multiple filters
+ since it didn't work in previous versions of libpng anyways
+ Optimized filter selection code
+ Fixed png_set_background() to allow using an arbitrary RGB color for
+ paletted images
+ Fixed gamma and background correction for paletted images, so
+ png_correct_palette is not needed unless you are correcting an
+ external palette (you will need to #define PNG_CORRECT_PALETTE_SUPPORTED
+ in pngconf.h) - if nobody uses this, it may disappear in the future.
+ Fixed bug with Borland 64K memory allocation (Alexander Lehmann)
+ Fixed bug in interlace handling (Smarasderagd, I think)
+ Added more error checking for writing and image to reduce invalid files
+ Separated read and write functions so that they won't both be linked
+ into a binary when only reading or writing functionality is used
+ New pngtest image also has interlacing and zTXt
+ Updated documentation to reflect new API
+
+Version 0.89c [June 17, 1996]
+ Bug fixes.
+
+Version 0.90 [January, 1997]
+ Made CRC errors/warnings on critical and ancillary chunks configurable
+ libpng will use the zlib CRC routines by (compile-time) default
+ Changed DOS small/medium model memory support - needs zlib 1.04 (Tim Wegner)
+ Added external C++ wrapper statements to png.h (Gilles Dauphin)
+ Allow PNG file to be read when some or all of file signature has already
+ been read from the beginning of the stream. ****This affects the size
+ of info_struct and invalidates all programs that use a shared libpng****
+ Fixed png_filler() declarations
+ Fixed? background color conversions
+ Fixed order of error function pointers to match documentation
+ Current chunk name is now available in png_struct to reduce the number
+ of nearly identical error messages (will simplify multi-lingual
+ support when available)
+ Try to get ready for unknown-chunk callback functions:
+ - previously read critical chunks are flagged, so the chunk handling
+ routines can determine if the chunk is in the right place
+ - all chunk handling routines have the same prototypes, so we will
+ be able to handle all chunks via a callback mechanism
+ Try to fix Linux "setjmp" buffer size problems
+ Removed png_large_malloc, png_large_free, and png_realloc functions.
+
+Version 0.95 [March, 1997]
+ Fixed bug in pngwutil.c allocating "up_row" twice and "avg_row" never
+ Fixed bug in PNG file signature compares when start != 0
+ Changed parameter type of png_set_filler(...filler...) from png_byte
+ to png_uint_32
+ Added test for MACOS to ensure that both math.h and fp.h are not #included
+ Added macros for libpng to be compiled as a Windows DLL (Andreas Kupries)
+ Added "packswap" transformation, which changes the endianness of
+ packed-pixel bytes (Kevin Bracey)
+ Added "strip_alpha" transformation, which removes the alpha channel of
+ input images without using it (not necessarily a good idea)
+ Added "swap_alpha" transformation, which puts the alpha channel in front
+ of the color bytes instead of after
+ Removed all implicit variable tests which assume NULL == 0 (I think)
+ Changed several variables to "png_size_t" to show 16/32-bit limitations
+ Added new pCAL chunk read/write support
+ Added experimental filter selection weighting (Greg Roelofs)
+ Removed old png_set_rgbx() and png_set_xrgb() functions that have been
+ obsolete for about 2 years now (use png_set_filler() instead)
+ Added macros to read 16- and 32-bit ints directly from buffer, to be
+ used only on those systems that support it (namely PowerPC and 680x0)
+ With some testing, this may become the default for MACOS/PPC systems.
+ Only calculate CRC on data if we are going to use it
+ Added macros for zTXt compression type PNG_zTXt_COMPRESSION_???
+ Added macros for simple libpng debugging output selectable at compile time
+ Removed PNG_READ_END_MODE in progressive reader (Smarasderagd)
+ More description of info_struct in libpng.txt and png.h
+ More instructions in example.c
+ More chunk types tested in pngtest.c
+ Renamed pngrcb.c to pngset.c, and all png_read_<chunk> functions to be
+ png_set_<chunk>. We now have corresponding png_get_<chunk>
+ functions in pngget.c to get information in info_ptr. This isolates
+ the application from the internal organization of png_info_struct
+ (good for shared library implementations).
+
+Version 0.96 [May, 1997]
+ Fixed serious bug with < 8bpp images introduced in 0.95
+ Fixed 256-color transparency bug (Greg Roelofs)
+ Fixed up documentation (Greg Roelofs, Laszlo Nyul)
+ Fixed "error" in pngconf.h for Linux setjmp() behavior
+ Fixed DOS medium model support (Tim Wegner)
+ Fixed png_check_keyword() for case with error in static string text
+ Added read of CRC after IEND chunk for embedded PNGs (Laszlo Nyul)
+ Added typecasts to quiet compiler errors
+ Added more debugging info
+
+Version 0.97 [January, 1998]
+ Removed PNG_USE_OWN_CRC capability
+ Relocated png_set_crc_action from pngrutil.c to pngrtran.c
+ Fixed typecasts of "new_key", etc. (Andreas Dilger)
+ Added RFC 1152 [sic] date support
+ Fixed bug in gamma handling of 4-bit grayscale
+ Added 2-bit grayscale gamma handling (Glenn R-P)
+ Added more typecasts. 65536L becomes (png_uint_32)65536L, etc. (Glenn R-P)
+ Minor corrections in libpng.txt
+ Added simple sRGB support (Glenn R-P)
+ Easier conditional compiling, e.g.,
+ define PNG_READ/WRITE_NOT_FULLY_SUPPORTED;
+ all configurable options can be selected from command-line instead
+ of having to edit pngconf.h (Glenn R-P)
+ Fixed memory leak in pngwrite.c (free info_ptr->text) (Glenn R-P)
+ Added more conditions for png_do_background, to avoid changing
+ black pixels to background when a background is supplied and
+ no pixels are transparent
+ Repaired PNG_NO_STDIO behavior
+ Tested NODIV support and made it default behavior (Greg Roelofs)
+ Added "-m" option and PNGTEST_DEBUG_MEMORY to pngtest (John Bowler)
+ Regularized version numbering scheme and bumped shared-library major
+ version number to 2 to avoid problems with libpng 0.89 apps
+ (Greg Roelofs)
+
+Version 0.98 [January, 1998]
+ Cleaned up some typos in libpng.txt and in code documentation
+ Fixed memory leaks in pCAL chunk processing (Glenn R-P and John Bowler)
+ Cosmetic change "display_gamma" to "screen_gamma" in pngrtran.c
+ Changed recommendation about file_gamma for PC images to .51 from .45,
+ in example.c and libpng.txt, added comments to distinguish between
+ screen_gamma, viewing_gamma, and display_gamma.
+ Changed all references to RFC1152 to read RFC1123 and changed the
+ PNG_TIME_RFC1152_SUPPORTED macro to PNG_TIME_RFC1123_SUPPORTED
+ Added png_invert_alpha capability (Glenn R-P -- suggestion by Jon Vincent)
+ Changed srgb_intent from png_byte to int to avoid compiler bugs
+
+Version 0.99 [January 30, 1998]
+ Free info_ptr->text instead of end_info_ptr->text in pngread.c (John Bowler)
+ Fixed a longstanding "packswap" bug in pngtrans.c
+ Fixed some inconsistencies in pngconf.h that prevented compiling with
+ PNG_READ_GAMMA_SUPPORTED and PNG_READ_hIST_SUPPORTED undefined
+ Fixed some typos and made other minor rearrangement of libpng.txt (Andreas)
+ Changed recommendation about file_gamma for PC images to .50 from .51 in
+ example.c and libpng.txt, and changed file_gamma for sRGB images to .45
+ Added a number of functions to access information from the png structure
+ png_get_image_height(), etc. (Glenn R-P, suggestion by Brad Pettit)
+ Added TARGET_MACOS similar to zlib-1.0.8
+ Define PNG_ALWAYS_EXTERN when __MWERKS__ && WIN32 are defined
+ Added type casting to all png_malloc() function calls
+
+Version 0.99a [January 31, 1998]
+ Added type casts and parentheses to all returns that return a value.(Tim W.)
+
+Version 0.99b [February 4, 1998]
+ Added type cast png_uint_32 on malloc function calls where needed.
+ Changed type of num_hist from png_uint_32 to int (same as num_palette).
+ Added checks for rowbytes overflow, in case png_size_t is less than 32 bits.
+ Renamed makefile.elf to makefile.lnx.
+
+Version 0.99c [February 7, 1998]
+ More type casting. Removed erroneous overflow test in pngmem.c.
+ Added png_buffered_memcpy() and png_buffered_memset(), apply them to rowbytes.
+ Added UNIX manual pages libpng.3 (incorporating libpng.txt) and png.5.
+
+Version 0.99d [February 11, 1998]
+ Renamed "far_to_near()" "png_far_to_near()"
+ Revised libpng.3
+ Version 99c "buffered" operations didn't work as intended. Replaced them
+ with png_memcpy_check() and png_memset_check().
+ Added many "if (png_ptr == NULL) return" to quell compiler warnings about
+ unused png_ptr, mostly in pngget.c and pngset.c.
+ Check for overlength tRNS chunk present when indexed-color PLTE is read.
+ Cleaned up spelling errors in libpng.3/libpng.txt
+ Corrected a problem with png_get_tRNS() which returned undefined trans array
+
+Version 0.99e [February 28, 1998]
+ Corrected png_get_tRNS() again.
+ Add parentheses for easier reading of pngget.c, fixed "||" should be "&&".
+ Touched up example.c to make more of it compileable, although the entire
+ file still can't be compiled (Willem van Schaik)
+ Fixed a bug in png_do_shift() (Bryan Tsai)
+ Added a space in png.h prototype for png_write_chunk_start()
+ Replaced pngtest.png with one created with zlib 1.1.1
+ Changed pngtest to report PASS even when file size is different (Jean-loup G.)
+ Corrected some logic errors in png_do_invert_alpha() (Chris Patterson)
+
+Version 0.99f [March 5, 1998]
+ Corrected a bug in pngpread() introduced in version 99c (Kevin Bracey)
+ Moved makefiles into a "scripts" directory, and added INSTALL instruction file
+ Added makefile.os2 and pngos2.def (A. Zabolotny) and makefile.s2x (W. Sebok)
+ Added pointers to "note on libpng versions" in makefile.lnx and README
+ Added row callback feature when reading and writing nonprogressive rows
+ and added a test of this feature in pngtest.c
+ Added user transform callbacks, with test of the feature in pngtest.c
+
+Version 0.99g [March 6, 1998, morning]
+ Minor changes to pngtest.c to suppress compiler warnings.
+ Removed "beta" language from documentation.
+
+Version 0.99h [March 6, 1998, evening]
+ Minor changes to previous minor changes to pngtest.c
+ Changed PNG_READ_NOT_FULLY_SUPPORTED to PNG_READ_TRANSFORMS_NOT_SUPPORTED
+ and added PNG_PROGRESSIVE_READ_NOT_SUPPORTED macro
+ Added user transform capability
+
+Version 1.00 [March 7, 1998]
+ Changed several typedefs in pngrutil.c
+ Added makefile.wat (Pawel Mrochen), updated makefile.tc3 (Willem van Schaik)
+ Replaced "while(1)" with "for(;;)"
+ Added PNGARG() to prototypes in pngtest.c and removed some prototypes
+ Updated some of the makefiles (Tom Lane)
+ Changed some typedefs (s_start, etc.) in pngrutil.c
+ Fixed dimensions of "short_months" array in pngwrite.c
+ Replaced ansi2knr.c with the one from jpeg-v6
+
+Version 1.0.0 [March 8, 1998]
+ Changed name from 1.00 to 1.0.0 (Adam Costello)
+ Added smakefile.ppc (with SCOPTIONS.ppc) for Amiga PPC (Andreas Kleinert)
+
+Version 1.0.0a [March 9, 1998]
+ Fixed three bugs in pngrtran.c to make gamma+background handling consistent
+ (Greg Roelofs)
+ Changed format of the PNG_LIBPNG_VER integer to xyyzz instead of xyz
+ for major, minor, and bugfix releases. This is 10001. (Adam Costello,
+ Tom Lane)
+ Make months range from 1-12 in png_convert_to_rfc1123
+
+Version 1.0.0b [March 13, 1998]
+ Quieted compiler complaints about two empty "for" loops in pngrutil.c
+ Minor changes to makefile.s2x
+ Removed #ifdef/#endif around a png_free() in pngread.c
+
+Version 1.0.1 [March 14, 1998]
+ Changed makefile.s2x to reduce security risk of using a relative pathname
+ Fixed some typos in the documentation (Greg).
+ Fixed a problem with value of "channels" returned by png_read_update_info()
+
+Version 1.0.1a [April 21, 1998]
+ Optimized Paeth calculations by replacing abs() function calls with intrinsics
+ plus other loop optimizations. Improves avg decoding speed by about 20%.
+ Commented out i386istic "align" compiler flags in makefile.lnx.
+ Reduced the default warning level in some makefiles, to make them consistent.
+ Removed references to IJG and JPEG in the ansi2knr.c copyright statement.
+ Fixed a bug in png_do_strip_filler with XXRRGGBB => RRGGBB transformation.
+ Added grayscale and 16-bit capability to png_do_read_filler().
+ Fixed a bug in pngset.c, introduced in version 0.99c, that sets rowbytes
+ too large when writing an image with bit_depth < 8 (Bob Dellaca).
+ Corrected some bugs in the experimental weighted filtering heuristics.
+ Moved a misplaced pngrutil code block that truncates tRNS if it has more
+ than num_palette entries -- test was done before num_palette was defined.
+ Fixed a png_convert_to_rfc1123() bug that converts day 31 to 0 (Steve Eddins).
+ Changed compiler flags in makefile.wat for better optimization
+ (Pawel Mrochen).
+
+Version 1.0.1b [May 2, 1998]
+ Relocated png_do_gray_to_rgb() within png_do_read_transformations() (Greg).
+ Relocated the png_composite macros from pngrtran.c to png.h (Greg).
+ Added makefile.sco (contributed by Mike Hopkirk).
+ Fixed two bugs (missing definitions of "istop") introduced in libpng-1.0.1a.
+ Fixed a bug in pngrtran.c that would set channels=5 under some circumstances.
+ More work on the Paeth-filtering, achieving imperceptible speedup
+ (A Kleinert).
+ More work on loop optimization which may help when compiled with C++
+ compilers.
+ Added warnings when people try to use transforms they've defined out.
+ Collapsed 4 "i" and "c" loops into single "i" loops in pngrtran and pngwtran.
+ Revised paragraph about png_set_expand() in libpng.txt and libpng.3 (Greg)
+
+Version 1.0.1c [May 11, 1998]
+ Fixed a bug in pngrtran.c (introduced in libpng-1.0.1a) where the masks for
+ filler bytes should have been 0xff instead of 0xf.
+ Added max_pixel_depth=32 in pngrutil.c when using FILLER with palette images.
+ Moved PNG_WRITE_WEIGHTED_FILTER_SUPPORTED and PNG_WRITE_FLUSH_SUPPORTED
+ out of the PNG_WRITE_TRANSFORMS_NOT_SUPPORTED block of pngconf.h
+ Added "PNG_NO_WRITE_TRANSFORMS" etc., as alternatives for *_NOT_SUPPORTED,
+ for consistency, in pngconf.h
+ Added individual "ifndef PNG_NO_[CAPABILITY]" in pngconf.h to make it easier
+ to remove unwanted capabilities via the compile line
+ Made some corrections to grammar (which, it's) in documentation (Greg).
+ Corrected example.c, use of row_pointers in png_write_image().
+
+Version 1.0.1d [May 24, 1998]
+ Corrected several statements that used side effects illegally in pngrutil.c
+ and pngtrans.c, that were introduced in version 1.0.1b
+ Revised png_read_rows() to avoid repeated if-testing for NULL (A Kleinert)
+ More corrections to example.c, use of row_pointers in png_write_image()
+ and png_read_rows().
+ Added pngdll.mak and pngdef.pas to scripts directory, contributed by
+ Bob Dellaca, to make a png32bd.dll with Borland C++ 4.5
+ Fixed error in example.c with png_set_text: num_text is 3, not 2 (Guido V.)
+ Changed several loops from count-down to count-up, for consistency.
+
+Version 1.0.1e [June 6, 1998]
+ Revised libpng.txt and libpng.3 description of png_set_read|write_fn(), and
+ added warnings when people try to set png_read_fn and png_write_fn in
+ the same structure.
+ Added a test such that png_do_gamma will be done when num_trans==0
+ for truecolor images that have defined a background. This corrects an
+ error that was introduced in libpng-0.90 that can cause gamma processing
+ to be skipped.
+ Added tests in png.h to include "trans" and "trans_values" in structures
+ when PNG_READ_BACKGROUND_SUPPORTED or PNG_READ_EXPAND_SUPPORTED is defined.
+ Add png_free(png_ptr->time_buffer) in png_destroy_read_struct()
+ Moved png_convert_to_rfc_1123() from pngwrite.c to png.c
+ Added capability for user-provided malloc_fn() and free_fn() functions,
+ and revised pngtest.c to demonstrate their use, replacing the
+ PNGTEST_DEBUG_MEM feature.
+ Added makefile.w32, for Microsoft C++ 4.0 and later (Tim Wegner).
+
+Version 1.0.2 [June 14, 1998]
+ Fixed two bugs in makefile.bor .
+
+Version 1.0.2a [December 30, 1998]
+ Replaced and extended code that was removed from png_set_filler() in 1.0.1a.
+ Fixed a bug in png_do_filler() that made it fail to write filler bytes in
+ the left-most pixel of each row (Kevin Bracey).
+ Changed "static pngcharp tIME_string" to "static char tIME_string[30]"
+ in pngtest.c (Duncan Simpson).
+ Fixed a bug in pngtest.c that caused pngtest to try to write a tIME chunk
+ even when no tIME chunk was present in the source file.
+ Fixed a problem in pngrutil.c: gray_to_rgb didn't always work with 16-bit.
+ Fixed a problem in png_read_push_finish_row(), which would not skip some
+ passes that it should skip, for images that are less than 3 pixels high.
+ Interchanged the order of calls to png_do_swap() and png_do_shift()
+ in pngwtran.c (John Cromer).
+ Added #ifdef PNG_DEBUG/#endif surrounding use of PNG_DEBUG in png.h .
+ Changed "bad adaptive filter type" from error to warning in pngrutil.c .
+ Fixed a documentation error about default filtering with 8-bit indexed-color.
+ Separated the PNG_NO_STDIO macro into PNG_NO_STDIO and PNG_NO_CONSOLE_IO
+ (L. Peter Deutsch).
+ Added png_set_rgb_to_gray() and png_get_rgb_to_gray_status() functions.
+ Added png_get_copyright() and png_get_header_version() functions.
+ Revised comments on png_set_progressive_read_fn() in libpng.txt and example.c
+ Added information about debugging in libpng.txt and libpng.3 .
+ Changed "ln -sf" to "ln -s -f" in makefile.s2x, makefile.lnx, and
+ makefile.sco.
+ Removed lines after Dynamic Dependencies" in makefile.aco .
+ Revised makefile.dec to make a shared library (Jeremie Petit).
+ Removed trailing blanks from all files.
+
+Version 1.0.2a [January 6, 1999]
+ Removed misplaced #endif and #ifdef PNG_NO_EXTERN near the end of png.h
+ Added "if" tests to silence complaints about unused png_ptr in png.h and png.c
+ Changed "check_if_png" function in example.c to return true (nonzero) if PNG.
+ Changed libpng.txt to demonstrate png_sig_cmp() instead of png_check_sig()
+ which is obsolete.
+
+Version 1.0.3 [January 14, 1999]
+ Added makefile.hux, for Hewlett Packard HPUX 10.20 and 11.00 (Jim Rice)
+ Added a statement of Y2K compliance in png.h, libpng.3, and Y2KINFO.
+
+Version 1.0.3a [August 12, 1999]
+ Added check for PNG_READ_INTERLACE_SUPPORTED in pngread.c; issue a warning
+ if an attempt is made to read an interlaced image when it's not supported.
+ Added check if png_ptr->trans is defined before freeing it in pngread.c
+ Modified the Y2K statement to include versions back to version 0.71
+ Fixed a bug in the check for valid IHDR bit_depth/color_types in pngrutil.c
+ Modified makefile.wat (added -zp8 flag, ".symbolic", changed some comments)
+ Replaced leading blanks with tab characters in makefile.hux
+ Changed "dworkin.wustl.edu" to "ccrc.wustl.edu" in various documents.
+ Changed (float)red and (float)green to (double)red, (double)green
+ in png_set_rgb_to_gray() to avoid "promotion" problems in AIX.
+ Fixed a bug in pngconf.h that omitted <stdio.h> when PNG_DEBUG==0 (K Bracey).
+ Reformatted libpng.3 and libpngpf.3 with proper fonts (script by J. vanZandt).
+ Updated documentation to refer to the PNG-1.2 specification.
+ Removed ansi2knr.c and left pointers to the latest source for ansi2knr.c
+ in makefile.knr, INSTALL, and README (L. Peter Deutsch)
+ Fixed bugs in calculation of the length of rowbytes when adding alpha
+ channels to 16-bit images, in pngrtran.c (Chris Nokleberg)
+ Added function png_set_user_transform_info() to store user_transform_ptr,
+ user_depth, and user_channels into the png_struct, and a function
+ png_get_user_transform_ptr() to retrieve the pointer (Chris Nokleberg)
+ Added function png_set_empty_plte_permitted() to make libpng useable
+ in MNG applications.
+ Corrected the typedef for png_free_ptr in png.h (Jesse Jones).
+ Correct gamma with srgb is 45455 instead of 45000 in pngrutil.c, to be
+ consistent with PNG-1.2, and allow variance of 500 before complaining.
+ Added assembler code contributed by Intel in file pngvcrd.c and modified
+ makefile.w32 to use it (Nirav Chhatrapati, INTEL Corporation,
+ Gilles Vollant)
+ Changed "ln -s -f" to "ln -f -s" in the makefiles to make Solaris happy.
+ Added some aliases for png_set_expand() in pngrtran.c, namely
+ png_set_expand_PLTE(), png_set_expand_depth(), and png_set_expand_tRNS()
+ (Greg Roelofs, in "PNG: The Definitive Guide").
+ Added makefile.beo for BEOS on X86, contributed by Sander Stok.
+
+Version 1.0.3b [August 26, 1999]
+ Replaced 2147483647L several places with PNG_MAX_UINT macro, defined in png.h
+ Changed leading blanks to tabs in all makefiles.
+ Define PNG_USE_PNGVCRD in makefile.w32, to get MMX assembler code.
+ Made alternate versions of png_set_expand() in pngrtran.c, namely
+ png_set_gray_1_2_4_to_8, png_set_palette_to_rgb, and png_set_tRNS_to_alpha
+ (Greg Roelofs, in "PNG: The Definitive Guide"). Deleted the 1.0.3a aliases.
+ Relocated start of 'extern "C"' block in png.h so it doesn't include pngconf.h
+ Revised calculation of num_blocks in pngmem.c to avoid a potentially
+ negative shift distance, whose results are undefined in the C language.
+ Added a check in pngset.c to prevent writing multiple tIME chunks.
+ Added a check in pngwrite.c to detect invalid small window_bits sizes.
+
+Version 1.0.3d [September 4, 1999]
+ Fixed type casting of igamma in pngrutil.c
+ Added new png_expand functions to scripts/pngdef.pas and pngos2.def
+ Added a demo read_user_transform_fn that examines the row filters in pngtest.c
+
+Version 1.0.4 [September 24, 1999, not distributed publicly]
+ Define PNG_ALWAYS_EXTERN in pngconf.h if __STDC__ is defined
+ Delete #define PNG_INTERNAL and include "png.h" from pngasmrd.h
+ Made several minor corrections to pngtest.c
+ Renamed the makefiles with longer but more user friendly extensions.
+ Copied the PNG copyright and license to a separate LICENSE file.
+ Revised documentation, png.h, and example.c to remove reference to
+ "viewing_gamma" which no longer appears in the PNG specification.
+ Revised pngvcrd.c to use MMX code for interlacing only on the final pass.
+ Updated pngvcrd.c to use the faster C filter algorithms from libpng-1.0.1a
+ Split makefile.win32vc into two versions, makefile.vcawin32 (uses MMX
+ assembler code) and makefile.vcwin32 (doesn't).
+ Added a CPU timing report to pngtest.c (enabled by defining PNGTEST_TIMING)
+ Added a copy of pngnow.png to the distribution.
+
+Version 1.0.4a [September 25, 1999]
+ Increase max_pixel_depth in pngrutil.c if a user transform needs it.
+ Changed several division operations to right-shifts in pngvcrd.c
+
+Version 1.0.4b [September 30, 1999]
+ Added parentheses in line 3732 of pngvcrd.c
+ Added a comment in makefile.linux warning about buggy -O3 in pgcc 2.95.1
+
+Version 1.0.4c [October 1, 1999]
+ Added a "png_check_version" function in png.c and pngtest.c that will generate
+ a helpful compiler error if an old png.h is found in the search path.
+ Changed type of png_user_transform_depth|channels from int to png_byte.
+ Added "Libpng is OSI Certified Open Source Software" statement to png.h
+
+Version 1.0.4d [October 6, 1999]
+ Changed 0.45 to 0.45455 in png_set_sRGB()
+ Removed unused PLTE entries from pngnow.png
+ Re-enabled some parts of pngvcrd.c (png_combine_row) that work properly.
+
+Version 1.0.4e [October 10, 1999]
+ Fixed sign error in pngvcrd.c (Greg Roelofs)
+ Replaced some instances of memcpy with simple assignments in pngvcrd (GR-P)
+
+Version 1.0.4f [October 15, 1999]
+ Surrounded example.c code with #if 0 .. #endif to prevent people from
+ inadvertently trying to compile it.
+ Changed png_get_header_version() from a function to a macro in png.h
+ Added type casting mostly in pngrtran.c and pngwtran.c
+ Removed some pointless "ptr = NULL" in pngmem.c
+ Added a "contrib" directory containing the source code from Greg's book.
+
+Version 1.0.5 [October 15, 1999]
+ Minor editing of the INSTALL and README files.
+
+Version 1.0.5a [October 23, 1999]
+ Added contrib/pngsuite and contrib/pngminus (Willem van Schaik)
+ Fixed a typo in the png_set_sRGB() function call in example.c (Jan Nijtmans)
+ Further optimization and bugfix of pngvcrd.c
+ Revised pngset.c so that it does not allocate or free memory in the user's
+ text_ptr structure. Instead, it makes its own copy.
+ Created separate write_end_info_struct in pngtest.c for a more severe test.
+ Added code in pngwrite.c to free info_ptr->text[i].key to stop a memory leak.
+
+Version 1.0.5b [November 23, 1999]
+ Moved PNG_FLAG_HAVE_CHUNK_HEADER, PNG_FLAG_BACKGROUND_IS_GRAY and
+ PNG_FLAG_WROTE_tIME from flags to mode.
+ Added png_write_info_before_PLTE() function.
+ Fixed some typecasting in contrib/gregbook/*.c
+ Updated scripts/makevms.com and added makevms.com to contrib/gregbook
+ and contrib/pngminus (Martin Zinser)
+
+Version 1.0.5c [November 26, 1999]
+ Moved png_get_header_version from png.h to png.c, to accommodate ansi2knr.
+ Removed all global arrays (according to PNG_NO_GLOBAL_ARRAYS macro), to
+ accommodate making DLL's: Moved usr_png_ver from global variable to function
+ png_get_header_ver() in png.c. Moved png_sig to png_sig_bytes in png.c and
+ eliminated use of png_sig in pngwutil.c. Moved the various png_CHNK arrays
+ into pngtypes.h. Eliminated use of global png_pass arrays. Declared the
+ png_CHNK and png_pass arrays to be "const". Made the global arrays
+ available to applications (although none are used in libpng itself) when
+ PNG_NO_GLOBAL_ARRAYS is not defined or when PNG_GLOBAL_ARRAYS is defined.
+ Removed some extraneous "-I" from contrib/pngminus/makefile.std
+ Changed the PNG_sRGB_INTENT macros in png.h to be consistent with PNG-1.2.
+ Change PNG_SRGB_INTENT to PNG_sRGB_INTENT in libpng.txt and libpng.3
+
+Version 1.0.5d [November 29, 1999]
+ Add type cast (png_const_charp) two places in png.c
+ Eliminated pngtypes.h; use macros instead to declare PNG_CHNK arrays.
+ Renamed "PNG_GLOBAL_ARRAYS" to "PNG_USE_GLOBAL_ARRAYS" and made available
+ to applications a macro "PNG_USE_LOCAL_ARRAYS".
+ comment out (with #ifdef) all the new declarations when
+ PNG_USE_GLOBAL_ARRAYS is defined.
+ Added PNG_EXPORT_VAR macro to accommodate making DLL's.
+
+Version 1.0.5e [November 30, 1999]
+ Added iCCP, iTXt, and sPLT support; added "lang" member to the png_text
+ structure; refactored the inflate/deflate support to make adding new chunks
+ with trailing compressed parts easier in the future, and added new functions
+ png_free_iCCP, png_free_pCAL, png_free_sPLT, png_free_text, png_get_iCCP,
+ png_get_spalettes, png_set_iCCP, png_set_spalettes (Eric S. Raymond).
+ NOTE: Applications that write text chunks MUST define png_text->lang
+ before calling png_set_text(). It must be set to NULL if you want to
+ write tEXt or zTXt chunks. If you want your application to be able to
+ run with older versions of libpng, use
+
+ #ifdef PNG_iTXt_SUPPORTED
+ png_text[i].lang = NULL;
+ #endif
+
+ Changed png_get_oFFs() and png_set_oFFs() to use signed rather than unsigned
+ offsets (Eric S. Raymond).
+ Combined PNG_READ_cHNK_SUPPORTED and PNG_WRITE_cHNK_SUPPORTED macros into
+ PNG_cHNK_SUPPORTED and combined the three types of PNG_text_SUPPORTED
+ macros, leaving the separate macros also available.
+ Removed comments on #endifs at the end of many short, non-nested #if-blocks.
+
+Version 1.0.5f [December 6, 1999]
+ Changed makefile.solaris to issue a warning about potential problems when
+ the ucb "ld" is in the path ahead of the ccs "ld".
+ Removed "- [date]" from the "synopsis" line in libpng.3 and libpngpf.3.
+ Added sCAL chunk support (Eric S. Raymond).
+
+Version 1.0.5g [December 7, 1999]
+ Fixed "png_free_spallettes" typo in png.h
+ Added code to handle new chunks in pngpread.c
+ Moved PNG_CHNK string macro definitions outside of PNG_NO_EXTERN block
+ Added "translated_key" to png_text structure and png_write_iTXt().
+ Added code in pngwrite.c to work around a newly discovered zlib bug.
+
+Version 1.0.5h [December 10, 1999]
+ NOTE: regarding the note for version 1.0.5e, the following must also
+ be included in your code:
+ png_text[i].translated_key = NULL;
+ Unknown chunk handling is now supported.
+ Option to eliminate all floating point support was added. Some new
+ fixed-point functions such as png_set_gAMA_fixed() were added.
+ Expanded tabs and removed trailing blanks in source files.
+
+Version 1.0.5i [December 13, 1999]
+ Added some type casts to silence compiler warnings.
+ Renamed "png_free_spalette" to "png_free_spalettes" for consistency.
+ Removed leading blanks from a #define in pngvcrd.c
+ Added some parameters to the new png_set_keep_unknown_chunks() function.
+ Added a test for up->location != 0 in the first instance of writing
+ unknown chunks in pngwrite.c
+ Changed "num" to "i" in png_free_spalettes() and png_free_unknowns() to
+ prevent recursion.
+ Added png_free_hIST() function.
+ Various patches to fix bugs in the sCAL and integer cHRM processing,
+ and to add some convenience macros for use with sCAL.
+
+Version 1.0.5j [December 21, 1999]
+ Changed "unit" parameter of png_write_sCAL from png_byte to int, to work
+ around buggy compilers.
+ Added new type "png_fixed_point" for integers that hold float*100000 values
+ Restored backward compatibility of tEXt/zTXt chunk processing:
+ Restored the first four members of png_text to the same order as v.1.0.5d.
+ Added members "lang_key" and "itxt_length" to png_text struct. Set
+ text_length=0 when "text" contains iTXt data. Use the "compression"
+ member to distinguish among tEXt/zTXt/iTXt types. Added
+ PNG_ITXT_COMPRESSION_NONE (1) and PNG_ITXT_COMPRESSION_zTXt(2) macros.
+ The "Note" above, about backward incompatibility of libpng-1.0.5e, no
+ longer applies.
+ Fixed png_read|write_iTXt() to read|write parameters in the right order,
+ and to write the iTXt chunk after IDAT if it appears in the end_ptr.
+ Added pnggccrd.c, version of pngvcrd.c Intel assembler for gcc (Greg Roelofs)
+ Reversed the order of trying to write floating-point and fixed-point gAMA.
+
+Version 1.0.5k [December 27, 1999]
+ Added many parentheses, e.g., "if (a && b & c)" becomes "if (a && (b & c))"
+ Added png_handle_as_unknown() function (Glenn)
+ Added png_free_chunk_list() function and chunk_list and num_chunk_list members
+ of png_ptr.
+ Eliminated erroneous warnings about multiple sPLT chunks and sPLT-after-PLTE.
+ Fixed a libpng-1.0.5h bug in pngrutil.c that was issuing erroneous warnings
+ about ignoring incorrect gAMA with sRGB (gAMA was in fact not ignored)
+ Added png_free_tRNS(); png_set_tRNS() now malloc's its own trans array (ESR).
+ Define png_get_int_32 when oFFs chunk is supported as well as when pCAL is.
+ Changed type of proflen from png_int_32 to png_uint_32 in png_get_iCCP().
+
+Version 1.0.5l [January 1, 2000]
+ Added functions png_set_read_user_chunk_fn() and png_get_user_chunk_ptr()
+ for setting a callback function to handle unknown chunks and for
+ retrieving the associated user pointer (Glenn).
+
+Version 1.0.5m [January 7, 2000]
+ Added high-level functions png_read_png(), png_write_png(), png_free_pixels().
+
+Version 1.0.5n [January 9, 2000]
+ Added png_free_PLTE() function, and modified png_set_PLTE() to malloc its
+ own memory for info_ptr->palette. This makes it safe for the calling
+ application to free its copy of the palette any time after it calls
+ png_set_PLTE().
+
+Version 1.0.5o [January 20, 2000]
+ Cosmetic changes only (removed some trailing blanks and TABs)
+
+Version 1.0.5p [January 31, 2000]
+ Renamed pngdll.mak to makefile.bd32
+ Cosmetic changes in pngtest.c
+
+Version 1.0.5q [February 5, 2000]
+ Relocated the makefile.solaris warning about PATH problems.
+ Fixed pngvcrd.c bug by pushing/popping registers in mmxsupport (Bruce Oberg)
+ Revised makefile.gcmmx
+ Added PNG_SETJMP_SUPPORTED, PNG_SETJMP_NOT_SUPPORTED, and PNG_ABORT() macros
+
+Version 1.0.5r [February 7, 2000]
+ Removed superfluous prototype for png_get_itxt from png.h
+ Fixed a bug in pngrtran.c that improperly expanded the background color.
+ Return *num_text=0 from png_get_text() when appropriate, and fix documentation
+ of png_get_text() in libpng.txt/libpng.3.
+
+Version 1.0.5s [February 18, 2000]
+ Added "png_jmp_env()" macro to pngconf.h, to help people migrate to the
+ new error handler that's planned for the next libpng release, and changed
+ example.c, pngtest.c, and contrib programs to use this macro.
+ Revised some of the DLL-export macros in pngconf.h (Greg Roelofs)
+ Fixed a bug in png_read_png() that caused it to fail to expand some images
+ that it should have expanded.
+ Fixed some mistakes in the unused and undocumented INCH_CONVERSIONS functions
+ in pngget.c
+ Changed the allocation of palette, history, and trans arrays back to
+ the version 1.0.5 method (linking instead of copying) which restores
+ backward compatibility with version 1.0.5. Added some remarks about
+ that in example.c. Added "free_me" member to info_ptr and png_ptr
+ and added png_free_data() function.
+ Updated makefile.linux and makefile.gccmmx to make directories conditionally.
+ Made cosmetic changes to pngasmrd.h
+ Added png_set_rows() and png_get_rows(), for use with png_read|write_png().
+ Modified png_read_png() to allocate info_ptr->row_pointers only if it
+ hasn't already been allocated.
+
+Version 1.0.5t [March 4, 2000]
+ Changed png_jmp_env() migration aiding macro to png_jmpbuf().
+ Fixed "interlace" typo (should be "interlaced") in contrib/gregbook/read2-x.c
+ Fixed bug with use of PNG_BEFORE_IHDR bit in png_ptr->mode, introduced when
+ PNG_FLAG_HAVE_CHUNK_HEADER was moved into png_ptr->mode in version 1.0.5b
+ Files in contrib/gregbook were revised to use png_jmpbuf() and to select
+ a 24-bit visual if one is available, and to allow abbreviated options.
+ Files in contrib/pngminus were revised to use the png_jmpbuf() macro.
+ Removed spaces in makefile.linux and makefile.gcmmx, introduced in 1.0.5s
+
+Version 1.0.5u [March 5, 2000]
+ Simplified the code that detects old png.h in png.c and pngtest.c
+ Renamed png_spalette (_p, _pp) to png_sPLT_t (_tp, _tpp)
+ Increased precision of rgb_to_gray calculations from 8 to 15 bits and
+ added png_set_rgb_to_gray_fixed() function.
+ Added makefile.bc32 (32-bit Borland C++, C mode)
+
+Version 1.0.5v [March 11, 2000]
+ Added some parentheses to the png_jmpbuf macro definition.
+ Updated references to the zlib home page, which has moved to freesoftware.com.
+ Corrected bugs in documentation regarding png_read_row() and png_write_row().
+ Updated documentation of png_rgb_to_gray calculations in libpng.3/libpng.txt.
+ Renamed makefile.borland,turboc3 back to makefile.bor,tc3 as in version 1.0.3,
+ revised borland makefiles; added makefile.ibmvac3 and makefile.gcc (Cosmin)
+
+Version 1.0.6 [March 20, 2000]
+ Minor revisions of makefile.bor, libpng.txt, and gregbook/rpng2-win.c
+ Added makefile.sggcc (SGI IRIX with gcc)
+
+Version 1.0.6d [April 7, 2000]
+ Changed sprintf() to strcpy() in png_write_sCAL_s() to work without STDIO
+ Added data_length parameter to png_decompress_chunk() function
+ Revised documentation to remove reference to abandoned png_free_chnk functions
+ Fixed an error in png_rgb_to_gray_fixed()
+ Revised example.c, usage of png_destroy_write_struct().
+ Renamed makefile.ibmvac3 to makefile.ibmc, added libpng.icc IBM project file
+ Added a check for info_ptr->free_me&PNG_FREE_TEXT when freeing text in png.c
+ Simplify png_sig_bytes() function to remove use of non-ISO-C strdup().
+
+Version 1.0.6e [April 9, 2000]
+ Added png_data_freer() function.
+ In the code that checks for over-length tRNS chunks, added check of
+ info_ptr->num_trans as well as png_ptr->num_trans (Matthias Benckmann)
+ Minor revisions of libpng.txt/libpng.3.
+ Check for existing data and free it if the free_me flag is set, in png_set_*()
+ and png_handle_*().
+ Only define PNG_WEIGHTED_FILTERS_SUPPORTED when PNG_FLOATING_POINT_SUPPORTED
+ is defined.
+ Changed several instances of PNG_NO_CONSOLE_ID to PNG_NO_STDIO in pngrutil.c
+ and mentioned the purposes of the two macros in libpng.txt/libpng.3.
+
+Version 1.0.6f [April 14, 2000]
+ Revised png_set_iCCP() and png_set_rows() to avoid prematurely freeing data.
+ Add checks in png_set_text() for NULL members of the input text structure.
+ Revised libpng.txt/libpng.3.
+ Removed superfluous prototype for png_set_iTXt from png.h
+ Removed "else" from pngread.c, after png_error(), and changed "0" to "length".
+ Changed several png_errors about malformed ancillary chunks to png_warnings.
+
+Version 1.0.6g [April 24, 2000]
+ Added png_pass-* arrays to pnggccrd.c when PNG_USE_LOCAL_ARRAYS is defined.
+ Relocated paragraph about png_set_background() in libpng.3/libpng.txt
+ and other revisions (Matthias Benckmann)
+ Relocated info_ptr->free_me, png_ptr->free_me, and other info_ptr and
+ png_ptr members to restore binary compatibility with libpng-1.0.5
+ (breaks compatibility with libpng-1.0.6).
+
+Version 1.0.6h [April 24, 2000]
+ Changed shared library so-number pattern from 2.x.y.z to xy.z (this builds
+ libpng.so.10 & libpng.so.10.6h instead of libpng.so.2 & libpng.so.2.1.0.6h)
+ This is a temporary change for test purposes.
+
+Version 1.0.6i [May 2, 2000]
+ Rearranged some members at the end of png_info and png_struct, to put
+ unknown_chunks_num and free_me within the original size of the png_structs
+ and free_me, png_read_user_fn, and png_free_fn within the original png_info,
+ because some old applications allocate the structs directly instead of
+ using png_create_*().
+ Added documentation of user memory functions in libpng.txt/libpng.3
+ Modified png_read_png so that it will use user_allocated row_pointers
+ if present, unless free_me directs that it be freed, and added description
+ of the use of png_set_rows() and png_get_rows() in libpng.txt/libpng.3.
+ Added PNG_LEGACY_SUPPORTED macro, and #ifdef out all new (since version
+ 1.00) members of png_struct and png_info, to regain binary compatibility
+ when you define this macro. Capabilities lost in this event
+ are user transforms (new in version 1.0.0),the user transform pointer
+ (new in version 1.0.2), rgb_to_gray (new in 1.0.5), iCCP, sCAL, sPLT,
+ the high-level interface, and unknown chunks support (all new in 1.0.6).
+ This was necessary because of old applications that allocate the structs
+ directly as authors were instructed to do in libpng-0.88 and earlier,
+ instead of using png_create_*().
+ Added modes PNG_CREATED_READ_STRUCT and PNG_CREATED_WRITE_STRUCT which
+ can be used to detect codes that directly allocate the structs, and
+ code to check these modes in png_read_init() and png_write_init() and
+ generate a libpng error if the modes aren't set and PNG_LEGACY_SUPPORTED
+ was not defined.
+ Added makefile.intel and updated makefile.watcom (Pawel Mrochen)
+
+Version 1.0.6j [May 3, 2000]
+ Overloaded png_read_init() and png_write_init() with macros that convert
+ calls to png_read_init_2() or png_write_init_2() that check the version
+ and structure sizes.
+
+Version 1.0.7beta11 [May 7, 2000]
+ Removed the new PNG_CREATED_READ_STRUCT and PNG_CREATED_WRITE_STRUCT modes
+ which are no longer used.
+ Eliminated the three new members of png_text when PNG_LEGACY_SUPPORTED is
+ defined or when neither PNG_READ_iTXt_SUPPORTED nor PNG_WRITE_iTXT_SUPPORTED
+ is defined.
+ Made PNG_NO_READ|WRITE_iTXt the default setting, to avoid memory
+ overrun when old applications fill the info_ptr->text structure directly.
+ Added PNGAPI macro, and added it to the definitions of all exported functions.
+ Relocated version macro definitions ahead of the includes of zlib.h and
+ pngconf.h in png.h.
+
+Version 1.0.7beta12 [May 12, 2000]
+ Revised pngset.c to avoid a problem with expanding the png_debug macro.
+ Deleted some extraneous defines from pngconf.h
+ Made PNG_NO_CONSOLE_IO the default condition when PNG_BUILD_DLL is defined.
+ Use MSC _RPTn debugging instead of fprintf if _MSC_VER is defined.
+ Added png_access_version_number() function.
+ Check for mask&PNG_FREE_CHNK (for TEXT, SCAL, PCAL) in png_free_data().
+ Expanded libpng.3/libpng.txt information about png_data_freer().
+
+Version 1.0.7beta14 [May 17, 2000] (beta13 was not published)
+ Changed pnggccrd.c and pngvcrd.c to handle bad adaptive filter types as
+ warnings instead of errors, as pngrutil.c does.
+ Set the PNG_INFO_IDAT valid flag in png_set_rows() so png_write_png()
+ will actually write IDATs.
+ Made the default PNG_USE_LOCAL_ARRAYS depend on PNG_DLL instead of WIN32.
+ Make png_free_data() ignore its final parameter except when freeing data
+ that can have multiple instances (text, sPLT, unknowns).
+ Fixed a new bug in png_set_rows().
+ Removed info_ptr->valid tests from png_free_data(), as in version 1.0.5.
+ Added png_set_invalid() function.
+ Fixed incorrect illustrations of png_destroy_write_struct() in example.c.
+
+Version 1.0.7beta15 [May 30, 2000]
+ Revised the deliberately erroneous Linux setjmp code in pngconf.h to produce
+ fewer error messages.
+ Rearranged checks for Z_OK to check the most likely path first in pngpread.c
+ and pngwutil.c.
+ Added checks in pngtest.c for png_create_*() returning NULL, and mentioned
+ in libpng.txt/libpng.3 the need for applications to check this.
+ Changed names of png_default_*() functions in pngtest to pngtest_*().
+ Changed return type of png_get_x|y_offset_*() from png_uint_32 to png_int_32.
+ Fixed some bugs in the unused PNG_INCH_CONVERSIONS functions in pngget.c
+ Set each pointer to NULL after freeing it in png_free_data().
+ Worked around a problem in pngconf.h; AIX's strings.h defines an "index"
+ macro that conflicts with libpng's png_color_16.index. (Dimitri
+ Papadapoulos)
+ Added "msvc" directory with MSVC++ project files (Simon-Pierre Cadieux).
+
+Version 1.0.7beta16 [June 4, 2000]
+ Revised the workaround of AIX string.h "index" bug.
+ Added a check for overlength PLTE chunk in pngrutil.c.
+ Added PNG_NO_POINTER_INDEXING macro to use array-indexing instead of pointer
+ indexing in pngrutil.c and pngwutil.c to accommodate a buggy compiler.
+ Added a warning in png_decompress_chunk() when it runs out of data, e.g.
+ when it tries to read an erroneous PhotoShop iCCP chunk.
+ Added PNG_USE_DLL macro.
+ Revised the copyright/disclaimer/license notice.
+ Added contrib/msvctest directory
+
+Version 1.0.7rc1 [June 9, 2000]
+ Corrected the definition of PNG_TRANSFORM_INVERT_ALPHA (0x0400 not 0x0200)
+ Added contrib/visupng directory (Willem van Schaik)
+
+Version 1.0.7beta18 [June 23, 2000]
+ Revised PNGAPI definition, and pngvcrd.c to work with __GCC__
+ and do not redefine PNGAPI if it is passed in via a compiler directive.
+ Revised visupng/PngFile.c to remove returns from within the Try block.
+ Removed leading underscores from "_PNG_H" and "_PNG_SAVE_BSD_SOURCE" macros.
+ Updated contrib/visupng/cexcept.h to version 1.0.0.
+ Fixed bugs in pngwrite.c and pngwutil.c that prevented writing iCCP chunks.
+
+Version 1.0.7rc2 [June 28, 2000]
+ Updated license to include disclaimers required by UCITA.
+ Fixed "DJBPP" typo in pnggccrd.c introduced in beta18.
+
+Version 1.0.7 [July 1, 2000]
+ Revised the definition of "trans_values" in libpng.3/libpng.txt
+
+Version 1.0.8beta1 [July 8, 2000]
+ Added png_free(png_ptr, key) two places in pngpread.c to stop memory leaks.
+ Changed PNG_NO_STDIO to PNG_NO_CONSOLE_IO, several places in pngrutil.c and
+ pngwutil.c.
+ Changed PNG_EXPORT_VAR to use PNG_IMPEXP, in pngconf.h.
+ Removed unused "#include <assert.h>" from png.c
+ Added WindowsCE support.
+ Revised pnggccrd.c to work with gcc-2.95.2 and in the Cygwin environment.
+
+Version 1.0.8beta2 [July 10, 2000]
+ Added project files to the wince directory and made further revisions
+ of pngtest.c, pngrio.c, and pngwio.c in support of WindowsCE.
+
+Version 1.0.8beta3 [July 11, 2000]
+ Only set the PNG_FLAG_FREE_TRNS or PNG_FREE_TRNS flag in png_handle_tRNS()
+ for indexed-color input files to avoid potential double-freeing trans array
+ under some unusual conditions; problem was introduced in version 1.0.6f.
+ Further revisions to pngtest.c and files in the wince subdirectory.
+
+Version 1.0.8beta4 [July 14, 2000]
+ Added the files pngbar.png and pngbar.jpg to the distribution.
+ Added makefile.cygwin, and cygwin support in pngconf.h
+ Added PNG_NO_ZALLOC_ZERO macro (makes png_zalloc skip zeroing memory)
+
+Version 1.0.8rc1 [July 16, 2000]
+ Revised png_debug() macros and statements to eliminate compiler warnings.
+
+Version 1.0.8 [July 24, 2000]
+ Added png_flush() in pngwrite.c, after png_write_IEND().
+ Updated makefile.hpux to build a shared library.
+
+Version 1.0.9beta1 [November 10, 2000]
+ Fixed typo in scripts/makefile.hpux
+ Updated makevms.com in scripts and contrib/* and contrib/* (Martin Zinser)
+ Fixed seqence-point bug in contrib/pngminus/png2pnm (Martin Zinser)
+ Changed "cdrom.com" in documentation to "libpng.org"
+ Revised pnggccrd.c to get it all working, and updated makefile.gcmmx (Greg).
+ Changed type of "params" from voidp to png_voidp in png_read|write_png().
+ Make sure PNGAPI and PNG_IMPEXP are defined in pngconf.h.
+ Revised the 3 instances of WRITEFILE in pngtest.c.
+ Relocated "msvc" and "wince" project subdirectories into "dll" subdirectory.
+ Updated png.rc in dll/msvc project
+ Revised makefile.dec to define and use LIBPATH and INCPATH
+ Increased size of global png_libpng_ver[] array from 12 to 18 chars.
+ Made global png_libpng_ver[], png_sig[] and png_pass_*[] arrays const.
+ Removed duplicate png_crc_finish() from png_handle_bKGD() function.
+ Added a warning when application calls png_read_update_info() multiple times.
+ Revised makefile.cygwin
+ Fixed bugs in iCCP support in pngrutil.c and pngwutil.c.
+ Replaced png_set_empty_plte_permitted() with png_permit_mng_features().
+
+Version 1.0.9beta2 [November 19, 2000]
+ Renamed the "dll" subdirectory "projects".
+ Added borland project files to "projects" subdirectory.
+ Set VS_FF_PRERELEASE and VS_FF_PATCHED flags in msvc/png.rc when appropriate.
+ Add error message in png_set_compression_buffer_size() when malloc fails.
+
+Version 1.0.9beta3 [November 23, 2000]
+ Revised PNG_LIBPNG_BUILD_TYPE macro in png.h, used in the msvc project.
+ Removed the png_flush() in pngwrite.c that crashes some applications
+ that don't set png_output_flush_fn.
+ Added makefile.macosx and makefile.aix to scripts directory.
+
+Version 1.0.9beta4 [December 1, 2000]
+ Change png_chunk_warning to png_warning in png_check_keyword().
+ Increased the first part of msg buffer from 16 to 18 in png_chunk_error().
+
+Version 1.0.9beta5 [December 15, 2000]
+ Added support for filter method 64 (for PNG datastreams embedded in MNG).
+
+Version 1.0.9beta6 [December 18, 2000]
+ Revised png_set_filter() to accept filter method 64 when appropriate.
+ Added new PNG_HAVE_PNG_SIGNATURE bit to png_ptr->mode and use it to
+ help prevent applications from using MNG features in PNG datastreams.
+ Added png_permit_mng_features() function.
+ Revised libpng.3/libpng.txt. Changed "filter type" to "filter method".
+
+Version 1.0.9rc1 [December 23, 2000]
+ Revised test for PNG_HAVE_PNG_SIGNATURE in pngrutil.c
+ Fixed error handling of unknown compression type in png_decompress_chunk().
+ In pngconf.h, define __cdecl when _MSC_VER is defined.
+
+Version 1.0.9beta7 [December 28, 2000]
+ Changed PNG_TEXT_COMPRESSION_zTXt to PNG_COMPRESSION_TYPE_BASE several places.
+ Revised memory management in png_set_hIST and png_handle_hIST in a backward
+ compatible manner. PLTE and tRNS were revised similarly.
+ Revised the iCCP chunk reader to ignore trailing garbage.
+
+Version 1.0.9beta8 [January 12, 2001]
+ Moved pngasmrd.h into pngconf.h.
+ Improved handling of out-of-spec garbage iCCP chunks generated by PhotoShop.
+
+Version 1.0.9beta9 [January 15, 2001]
+ Added png_set_invalid, png_permit_mng_features, and png_mmx_supported to
+ wince and msvc project module definition files.
+ Minor revision of makefile.cygwin.
+ Fixed bug with progressive reading of narrow interlaced images in pngpread.c
+
+Version 1.0.9beta10 [January 16, 2001]
+ Do not typedef png_FILE_p in pngconf.h when PNG_NO_STDIO is defined.
+ Fixed "png_mmx_supported" typo in project definition files.
+
+Version 1.0.9beta11 [January 19, 2001]
+ Updated makefile.sgi to make shared library.
+ Removed png_mmx_support() function and disabled PNG_MNG_FEATURES_SUPPORTED
+ by default, for the benefit of DLL forward compatibility. These will
+ be re-enabled in version 1.2.0.
+
+Version 1.0.9rc2 [January 22, 2001]
+ Revised cygwin support.
+
+Version 1.0.9 [January 31, 2001]
+ Added check of cygwin's ALL_STATIC in pngconf.h
+ Added "-nommx" parameter to contrib/gregbook/rpng2-win and rpng2-x demos.
+
+Version 1.0.10beta1 [March 14, 2001]
+ Revised makefile.dec, makefile.sgi, and makefile.sggcc; added makefile.hpgcc.
+ Reformatted libpng.3 to eliminate bad line breaks.
+ Added checks for _mmx_supported in the read_filter_row function of pnggccrd.c
+ Added prototype for png_mmx_support() near the top of pnggccrd.c
+ Moved some error checking from png_handle_IHDR to png_set_IHDR.
+ Added PNG_NO_READ_SUPPORTED and PNG_NO_WRITE_SUPPORTED macros.
+ Revised png_mmx_support() function in pnggccrd.c
+ Restored version 1.0.8 PNG_WRITE_EMPTY_PLTE_SUPPORTED behavior in pngwutil.c
+ Fixed memory leak in contrib/visupng/PngFile.c
+ Fixed bugs in png_combine_row() in pnggccrd.c and pngvcrd.c (C version)
+ Added warnings when retrieving or setting gamma=0.
+ Increased the first part of msg buffer from 16 to 18 in png_chunk_warning().
+
+Version 1.0.10rc1 [March 23, 2001]
+ Changed all instances of memcpy, strcpy, and strlen to png_memcpy, png_strcpy,
+ and png_strlen.
+ Revised png_mmx_supported() function in pnggccrd.c to return proper value.
+ Fixed bug in progressive reading (pngpread.c) with small images (height < 8).
+
+Version 1.0.10 [March 30, 2001]
+ Deleted extraneous space (introduced in 1.0.9) from line 42 of makefile.cygwin
+ Added beos project files (Chris Herborth)
+
+Version 1.0.11beta1 [April 3, 2001]
+ Added type casts on several png_malloc() calls (Dimitri Papadapoulos).
+ Removed a no-longer needed AIX work-around from pngconf.h
+ Changed several "//" single-line comments to C-style in pnggccrd.c
+
+Version 1.0.11beta2 [April 11, 2001]
+ Removed PNGAPI from several functions whose prototypes did not have PNGAPI.
+ Updated scripts/pngos2.def
+
+Version 1.0.11beta3 [April 14, 2001]
+ Added checking the results of many instances of png_malloc() for NULL
+
+Version 1.0.11beta4 [April 20, 2001]
+ Undid the changes from version 1.0.11beta3. Added a check for NULL return
+ from user's malloc_fn().
+ Removed some useless type casts of the NULL pointer.
+ Added makefile.netbsd
+
+Version 1.0.11 [April 27, 2001]
+ Revised makefile.netbsd
+
+Version 1.0.12beta1 [May 14, 2001]
+ Test for Windows platform in pngconf.h when including malloc.h (Emmanuel Blot)
+ Updated makefile.cygwin and handling of Cygwin's ALL_STATIC in pngconf.h
+ Added some never-to-be-executed code in pnggccrd.c to quiet compiler warnings.
+ Eliminated the png_error about apps using png_read|write_init(). Instead,
+ libpng will reallocate the png_struct and info_struct if they are too small.
+ This retains future binary compatibility for old applications written for
+ libpng-0.88 and earlier.
+
+Version 1.2.0beta1 [May 6, 2001]
+ Bumped DLLNUM to 2.
+ Re-enabled PNG_MNG_FEATURES_SUPPORTED and enabled PNG_ASSEMBLER_CODE_SUPPORTED
+ by default.
+ Added runtime selection of MMX features.
+ Added png_set_strip_error_numbers function and related macros.
+
+Version 1.2.0beta2 [May 7, 2001]
+ Finished merging 1.2.0beta1 with version 1.0.11
+ Added a check for attempts to read or write PLTE in grayscale PNG datastreams.
+
+Version 1.2.0beta3 [May 17, 2001]
+ Enabled user memory function by default.
+ Modified png_create_struct so it passes user mem_ptr to user memory allocator.
+ Increased png_mng_features flag from png_byte to png_uint_32.
+ Bumped shared-library (so-number) and dll-number to 3.
+
+Version 1.2.0beta4 [June 23, 2001]
+ Check for missing profile length field in iCCP chunk and free chunk_data
+ in case of truncated iCCP chunk.
+ Bumped shared-library number to 3 in makefile.sgi and makefile.sggcc
+ Bumped dll-number from 2 to 3 in makefile.cygwin
+ Revised contrib/gregbook/rpng*-x.c to avoid a memory leak and to exit cleanly
+ if user attempts to run it on an 8-bit display.
+ Updated contrib/gregbook
+ Use png_malloc instead of png_zalloc to allocate palette in pngset.c
+ Updated makefile.ibmc
+ Added some typecasts to eliminate gcc 3.0 warnings. Changed prototypes
+ of png_write_oFFS width and height from png_uint_32 to png_int_32.
+ Updated example.c
+ Revised prototypes for png_debug_malloc and png_debug_free in pngtest.c
+
+Version 1.2.0beta5 [August 8, 2001]
+ Revised contrib/gregbook
+ Revised makefile.gcmmx
+ Revised pnggccrd.c to conditionally compile some thread-unsafe code only
+ when PNG_THREAD_UNSAFE_OK is defined.
+ Added tests to prevent pngwutil.c from writing a bKGD or tRNS chunk with
+ value exceeding 2^bit_depth-1
+ Revised makefile.sgi and makefile.sggcc
+ Replaced calls to fprintf(stderr,...) with png_warning() in pnggccrd.c
+ Removed restriction that do_invert_mono only operate on 1-bit opaque files
+
+Version 1.2.0 [September 1, 2001]
+ Changed a png_warning() to png_debug() in pnggccrd.c
+ Fixed contrib/gregbook/rpng-x.c, rpng2-x.c to avoid crash with XFreeGC().
+
+Version 1.2.1beta1 [October 19, 2001]
+ Revised makefile.std in contrib/pngminus
+ Include background_1 in png_struct regardless of gamma support.
+ Revised makefile.netbsd and makefile.macosx, added makefile.darwin.
+ Revised example.c to provide more details about using row_callback().
+
+Version 1.2.1beta2 [October 25, 2001]
+ Added type cast to each NULL appearing in a function call, except for
+ WINCE functions.
+ Added makefile.so9.
+
+Version 1.2.1beta3 [October 27, 2001]
+ Removed type casts from all NULLs.
+ Simplified png_create_struct_2().
+
+Version 1.2.1beta4 [November 7, 2001]
+ Revised png_create_info_struct() and png_creat_struct_2().
+ Added error message if png_write_info() was omitted.
+ Type cast NULLs appearing in function calls when _NO_PROTO or
+ PNG_TYPECAST_NULL is defined.
+
+Version 1.2.1rc1 [November 24, 2001]
+ Type cast NULLs appearing in function calls except when PNG_NO_TYPECAST_NULL
+ is defined.
+ Changed typecast of "size" argument to png_size_t in pngmem.c calls to
+ the user malloc_fn, to agree with the prototype in png.h
+ Added a pop/push operation to pnggccrd.c, to preserve Eflag (Maxim Sobolev)
+ Updated makefile.sgi to recognize LIBPATH and INCPATH.
+ Updated various makefiles so "make clean" does not remove previous major
+ version of the shared library.
+
+Version 1.2.1rc2 [December 4, 2001]
+ Always allocate 256-entry internal palette, hist, and trans arrays, to
+ avoid out-of-bounds memory reference caused by invalid PNG datastreams.
+ Added a check for prefix_length > data_length in iCCP chunk handler.
+
+Version 1.2.1 [December 7, 2001]
+ None.
+
+Version 1.2.2beta1 [February 22, 2002]
+ Fixed a bug with reading the length of iCCP profiles (Larry Reeves).
+ Revised makefile.linux, makefile.gcmmx, and makefile.sgi to generate
+ libpng.a, libpng12.so (not libpng.so.3), and libpng12/png.h
+ Revised makefile.darwin to remove "-undefined suppress" option.
+ Added checks for gamma and chromaticity values over 21474.83, which exceed
+ the limit for PNG unsigned 32-bit integers when encoded.
+ Revised calls to png_create_read_struct() and png_create_write_struct()
+ for simpler debugging.
+ Revised png_zalloc() so zlib handles errors (uses PNG_FLAG_MALLOC_NULL_MEM_OK)
+
+Version 1.2.2beta2 [February 23, 2002]
+ Check chunk_length and idat_size for invalid (over PNG_MAX_UINT) lengths.
+ Check for invalid image dimensions in png_get_IHDR.
+ Added missing "fi;" in the install target of the SGI makefiles.
+ Added install-static to all makefiles that make shared libraries.
+ Always do gamma compensation when image is partially transparent.
+
+Version 1.2.2beta3 [March 7, 2002]
+ Compute background.gray and background_1.gray even when color_type is RGB
+ in case image gets reduced to gray later.
+ Modified shared-library makefiles to install pkgconfig/libpngNN.pc.
+ Export (with PNGAPI) png_zalloc, png_zfree, and png_handle_as_unknown
+ Removed unused png_write_destroy_info prototype from png.h
+ Eliminated incorrect use of width_mmx from pnggccrd.c in pixel_bytes == 8 case
+ Added install-shared target to all makefiles that make shared libraries.
+ Stopped a double free of palette, hist, and trans when not using free_me.
+ Added makefile.32sunu for Sun Ultra 32 and makefile.64sunu for Sun Ultra 64.
+
+Version 1.2.2beta4 [March 8, 2002]
+ Compute background.gray and background_1.gray even when color_type is RGB
+ in case image gets reduced to gray later (Jason Summers).
+ Relocated a misplaced /bin/rm in the "install-shared" makefile targets
+ Added PNG_1_0_X macro which can be used to build a 1.0.x-compatible library.
+
+Version 1.2.2beta5 [March 26, 2002]
+ Added missing PNGAPI to several function definitions.
+ Check for invalid bit_depth or color_type in png_get_IHDR(), and
+ check for missing PLTE or IHDR in png_push_read_chunk() (Matthias Clasen).
+ Revised iTXt support to accept NULL for lang and lang_key.
+ Compute gamma for color components of background even when color_type is gray.
+ Changed "()" to "{}" in scripts/libpng.pc.in.
+ Revised makefiles to put png.h and pngconf.h only in $prefix/include/libpngNN
+ Revised makefiles to make symlink to libpng.so.NN in addition to libpngNN.so
+
+Version 1.2.2beta6 [March 31, 2002]
+
+Version 1.0.13beta1 [March 31, 2002]
+ Prevent png_zalloc() from trying to memset memory that it failed to acquire.
+ Add typecasts of PNG_MAX_UINT in pngset_cHRM_fixed() (Matt Holgate).
+ Ensure that the right function (user or default) is used to free the
+ png_struct after an error in png_create_read_struct_2().
+
+Version 1.2.2rc1 [April 7, 2002]
+
+Version 1.0.13rc1 [April 7, 2002]
+ Save the ebx register in pnggccrd.c (Sami Farin)
+ Add "mem_ptr = png_ptr->mem_ptr" in png_destroy_write_struct() (Paul Gardner).
+ Updated makefiles to put headers in include/libpng and remove old include/*.h.
+
+Version 1.2.2 [April 15, 2002]
+
+Version 1.0.13 [April 15, 2002]
+ Revised description of png_set_filter() in libpng.3/libpng.txt.
+ Revised makefile.netbsd and added makefile.neNNbsd and makefile.freebsd
+
+Version 1.0.13patch01 [April 17, 2002]
+
+Version 1.2.2patch01 [April 17, 2002]
+ Changed ${PNGMAJ}.${PNGVER} bug to ${PNGVER} in makefile.sgi and
+ makefile.sggcc
+ Fixed VER -> PNGVER typo in makefile.macosx and added install-static to
+ install
+ Added install: target to makefile.32sunu and makefile.64sunu
+
+Version 1.0.13patch03 [April 18, 2002]
+
+Version 1.2.2patch03 [April 18, 2002]
+ Revised 15 makefiles to link libpng.a to libpngNN.a and the include libpng
+ subdirectory to libpngNN subdirectory without the full pathname.
+ Moved generation of libpng.pc from "install" to "all" in 15 makefiles.
+
+Version 1.2.3rc1 [April 28, 2002]
+ Added install-man target to 15 makefiles (Dimitri Papadopolous-Orfanos).
+ Added $(DESTDIR) feature to 24 makefiles (Tim Mooney)
+ Fixed bug with $prefix, should be $(prefix) in makefile.hpux.
+ Updated cygwin-specific portion of pngconf.h and revised makefile.cygwin
+ Added a link from libpngNN.pc to libpng.pc in 15 makefiles.
+ Added links from include/libpngNN/*.h to include/*.h in 24 makefiles.
+ Revised makefile.darwin to make relative links without full pathname.
+ Added setjmp() at the end of png_create_*_struct_2() in case user forgets
+ to put one in their application.
+ Restored png_zalloc() and png_zfree() prototypes to version 1.2.1 and
+ removed them from module definition files.
+
+Version 1.2.3rc2 [May 1, 2002]
+ Fixed bug in reporting number of channels in pngget.c and pngset.c,
+ that was introduced in version 1.2.2beta5.
+ Exported png_zalloc(), png_zfree(), png_default_read(), png_default_write(),
+ png_default_flush(), and png_push_fill_buffer() and included them in
+ module definition files.
+ Added "libpng.pc" dependency to the "install-shared" target in 15 makefiles.
+
+Version 1.2.3rc3 [May 1, 2002]
+ Revised prototype for png_default_flush()
+ Remove old libpng.pc and libpngNN.pc before installing new ones.
+
+Version 1.2.3rc4 [May 2, 2002]
+ Typos in *.def files (png_default_read|write -> png_default_read|write_data)
+ In makefiles, changed rm libpng.NN.pc to rm libpngNN.pc
+ Added libpng-config and libpngNN-config and modified makefiles to install
+ them.
+ Changed $(MANPATH) to $(DESTDIR)$(MANPATH) in makefiles
+ Added "Win32 DLL VB" configuration to projects/msvc/libpng.dsp
+
+Version 1.2.3rc5 [May 11, 2002]
+ Changed "error" and "message" in prototypes to "error_message" and
+ "warning_message" to avoid namespace conflict.
+ Revised 15 makefiles to build libpng-config from libpng-config-*.in
+ Once more restored png_zalloc and png_zfree to regular nonexported form.
+ Restored png_default_read|write_data, png_default_flush, png_read_fill_buffer
+ to nonexported form, but with PNGAPI, and removed them from module def
+ files.
+
+Version 1.2.3rc6 [May 14, 2002]
+ Removed "PNGAPI" from png_zalloc() and png_zfree() in png.c
+ Changed "Gz" to "Gd" in projects/msvc/libpng.dsp and zlib.dsp.
+ Removed leftover libpng-config "sed" script from four makefiles.
+ Revised libpng-config creating script in 16 makefiles.
+
+Version 1.2.3 [May 22, 2002]
+ Revised libpng-config target in makefile.cygwin.
+ Removed description of png_set_mem_fn() from documentation.
+ Revised makefile.freebsd.
+ Minor cosmetic changes to 15 makefiles, e.g., $(DI) = $(DESTDIR)/$(INCDIR).
+ Revised projects/msvc/README.txt
+ Changed -lpng to -lpngNN in LDFLAGS in several makefiles.
+
+Version 1.2.4beta1 [May 24, 2002]
+ Added libpng.pc and libpng-config to "all:" target in 16 makefiles.
+ Fixed bug in 16 makefiles: $(DESTDIR)/$(LIBPATH) to $(DESTDIR)$(LIBPATH)
+ Added missing "\" before closing double quote in makefile.gcmmx.
+ Plugged various memory leaks; added png_malloc_warn() and png_set_text_2()
+ functions.
+
+Version 1.2.4beta2 [June 25, 2002]
+ Plugged memory leak of png_ptr->current_text (Matt Holgate).
+ Check for buffer overflow before reading CRC in pngpread.c (Warwick Allison)
+ Added -soname to the loader flags in makefile.dec, makefile.sgi, and
+ makefile.sggcc.
+ Added "test-installed" target to makefile.linux, makefile.gcmmx,
+ makefile.sgi, and makefile.sggcc.
+
+Version 1.2.4beta3 [June 28, 2002]
+ Plugged memory leak of row_buf in pngtest.c when there is a png_error().
+ Detect buffer overflow in pngpread.c when IDAT is corrupted with extra data.
+ Added "test-installed" target to makefile.32sunu, makefile.64sunu,
+ makefile.beos, makefile.darwin, makefile.dec, makefile.macosx,
+ makefile.solaris, makefile.hpux, makefile.hpgcc, and makefile.so9.
+
+Version 1.2.4rc1 and 1.0.14rc1 [July 2, 2002]
+ Added "test-installed" target to makefile.cygwin and makefile.sco.
+ Revised pnggccrd.c to be able to back out version 1.0.x via PNG_1_0_X macro.
+
+Version 1.2.4 and 1.0.14 [July 8, 2002]
+ Changed png_warning() to png_error() when width is too large to process.
+
+Version 1.2.4patch01 [July 20, 2002]
+ Revised makefile.cygwin to use DLL number 12 instead of 13.
+
+Version 1.2.5beta1 [August 6, 2002]
+ Added code to contrib/gregbook/readpng2.c to ignore unused chunks.
+ Replaced toucan.png in contrib/gregbook (it has been corrupt since 1.0.11)
+ Removed some stray *.o files from contrib/gregbook.
+ Changed png_error() to png_warning() about "Too much data" in pngpread.c
+ and about "Extra compressed data" in pngrutil.c.
+ Prevent png_ptr->pass from exceeding 7 in png_push_finish_row().
+ Updated makefile.hpgcc
+ Updated png.c and pnggccrd.c handling of return from png_mmx_support()
+
+Version 1.2.5beta2 [August 15, 2002]
+ Only issue png_warning() about "Too much data" in pngpread.c when avail_in
+ is nonzero.
+ Updated makefiles to install a separate libpng.so.3 with its own rpath.
+
+Version 1.2.5rc1 and 1.0.15rc1 [August 24, 2002]
+ Revised makefiles to not remove previous minor versions of shared libraries.
+
+Version 1.2.5rc2 and 1.0.15rc2 [September 16, 2002]
+ Revised 13 makefiles to remove "-lz" and "-L$(ZLIBLIB)", etc., from shared
+ library loader directive.
+ Added missing "$OBJSDLL" line to makefile.gcmmx.
+ Added missing "; fi" to makefile.32sunu.
+
+Version 1.2.5rc3 and 1.0.15rc3 [September 18, 2002]
+ Revised libpng-config script.
+
+Version 1.2.5 and 1.0.15 [October 3, 2002]
+ Revised makefile.macosx, makefile.darwin, makefile.hpgcc, and makefile.hpux,
+ and makefile.aix.
+ Relocated two misplaced PNGAPI lines in pngtest.c
+
+Version 1.2.6beta1 [October 22, 2002]
+ Commented out warning about uninitialized mmx_support in pnggccrd.c.
+ Changed "IBMCPP__" flag to "__IBMCPP__" in pngconf.h.
+ Relocated two more misplaced PNGAPI lines in pngtest.c
+ Fixed memory overrun bug in png_do_read_filler() with 16-bit datastreams,
+ introduced in version 1.0.2.
+ Revised makefile.macosx, makefile.dec, makefile.aix, and makefile.32sunu.
+
+Version 1.2.6beta2 [November 1, 2002]
+ Added libpng-config "--ldopts" output.
+ Added "AR=ar" and "ARFLAGS=rc" and changed "ar rc" to "$(AR) $(ARFLAGS)"
+ in makefiles.
+
+Version 1.2.6beta3 [July 18, 2004]
+ Reverted makefile changes from version 1.2.6beta2 and some of the changes
+ from version 1.2.6beta1; these will be postponed until version 1.2.7.
+ Version 1.2.6 is going to be a simple bugfix release.
+ Changed the one instance of "ln -sf" to "ln -f -s" in each Sun makefile.
+ Fixed potential overrun in pngerror.c by using strncpy instead of memcpy.
+ Added "#!/bin/sh" at the top of configure, for recognition of the
+ 'x' flag under Cygwin (Cosmin).
+ Optimized vacuous tests that silence compiler warnings, in png.c (Cosmin).
+ Added support for PNG_USER_CONFIG, in pngconf.h (Cosmin).
+ Fixed the special memory handler for Borland C under DOS, in pngmem.c
+ (Cosmin).
+ Removed some spurious assignments in pngrutil.c (Cosmin).
+ Replaced 65536 with 65536L, and 0xffff with 0xffffL, to silence warnings
+ on 16-bit platforms (Cosmin).
+ Enclosed shift op expressions in parentheses, to silence warnings (Cosmin).
+ Used proper type png_fixed_point, to avoid problems on 16-bit platforms,
+ in png_handle_sRGB() (Cosmin).
+ Added compression_type to png_struct, and optimized the window size
+ inside the deflate stream (Cosmin).
+ Fixed definition of isnonalpha(), in pngerror.c and pngrutil.c (Cosmin).
+ Fixed handling of unknown chunks that come after IDAT (Cosmin).
+ Allowed png_error() and png_warning() to work even if png_ptr == NULL
+ (Cosmin).
+ Replaced row_info->rowbytes with row_bytes in png_write_find_filter()
+ (Cosmin).
+ Fixed definition of PNG_LIBPNG_VER_DLLNUM (Simon-Pierre).
+ Used PNG_LIBPNG_VER and PNG_LIBPNG_VER_STRING instead of the hardcoded
+ values in png.c (Simon-Pierre, Cosmin).
+ Initialized png_libpng_ver[] with PNG_LIBPNG_VER_STRING (Simon-Pierre).
+ Replaced PNG_LIBPNG_VER_MAJOR with PNG_LIBPNG_VER_DLLNUM in png.rc
+ (Simon-Pierre).
+ Moved the definition of PNG_HEADER_VERSION_STRING near the definitions
+ of the other PNG_LIBPNG_VER_... symbols in png.h (Cosmin).
+ Relocated #ifndef PNGAPI guards in pngconf.h (Simon-Pierre, Cosmin).
+ Updated scripts/makefile.vc(a)win32 (Cosmin).
+ Updated the MSVC project (Simon-Pierre, Cosmin).
+ Updated the Borland C++ Builder project (Cosmin).
+ Avoided access to asm_flags in pngvcrd.c, if PNG_1_0_X is defined (Cosmin).
+ Commented out warning about uninitialized mmx_support in pngvcrd.c (Cosmin).
+ Removed scripts/makefile.bd32 and scripts/pngdef.pas (Cosmin).
+ Added extra guard around inclusion of Turbo C memory headers, in pngconf.h
+ (Cosmin).
+ Renamed projects/msvc/ to projects/visualc6/, and projects/borland/ to
+ projects/cbuilder5/ (Cosmin).
+ Moved projects/visualc6/png32ms.def to scripts/pngw32.def,
+ and projects/visualc6/png.rc to scripts/pngw32.rc (Cosmin).
+ Added projects/visualc6/pngtest.dsp; removed contrib/msvctest/ (Cosmin).
+ Changed line endings to DOS style in cbuilder5 and visualc6 files, even
+ in the tar.* distributions (Cosmin).
+ Updated contrib/visupng/VisualPng.dsp (Cosmin).
+ Updated contrib/visupng/cexcept.h to version 2.0.0 (Cosmin).
+ Added a separate distribution with "configure" and supporting files (Junichi).
+
+Version 1.2.6beta4 [July 28, 2004]
+ Added user ability to change png_size_t via a PNG_SIZE_T macro.
+ Added png_sizeof() and png_convert_size() functions.
+ Added PNG_SIZE_MAX (maximum value of a png_size_t variable.
+ Added check in png_malloc_default() for (size_t)size != (png_uint_32)size
+ which would indicate an overflow.
+ Changed sPLT failure action from png_error to png_warning and abandon chunk.
+ Changed sCAL and iCCP failures from png_error to png_warning and abandon.
+ Added png_get_uint_31(png_ptr, buf) function.
+ Added PNG_UINT_32_MAX macro.
+ Renamed PNG_MAX_UINT to PNG_UINT_31_MAX.
+ Made png_zalloc() issue a png_warning and return NULL on potential
+ overflow.
+ Turn on PNG_NO_ZALLOC_ZERO by default in version 1.2.x
+ Revised "clobber list" in pnggccrd.c so it will compile under gcc-3.4.
+ Revised Borland portion of png_malloc() to return NULL or issue
+ png_error() according to setting of PNG_FLAG_MALLOC_NULL_MEM_OK.
+ Added PNG_NO_SEQUENTIAL_READ_SUPPORTED macro to conditionally remove
+ sequential read support.
+ Added some "#if PNG_WRITE_SUPPORTED" blocks.
+ Added #ifdef to remove some redundancy in png_malloc_default().
+ Use png_malloc instead of png_zalloc to allocate the pallete.
+
+Version 1.0.16rc1 and 1.2.6rc1 [August 4, 2004]
+ Fixed buffer overflow vulnerability (CVE-2004-0597) in png_handle_tRNS().
+ Fixed NULL dereference vulnerability (CVE-2004-0598) in png_handle_iCCP().
+ Fixed integer overflow vulnerability (CVE-2004-0599) in png_read_png().
+ Fixed some harmless bugs in png_handle_sBIT, etc, that would cause
+ duplicate chunk types to go undetected.
+ Fixed some timestamps in the -config version
+ Rearranged order of processing of color types in png_handle_tRNS().
+ Added ROWBYTES macro to calculate rowbytes without integer overflow.
+ Updated makefile.darwin and removed makefile.macosx from scripts directory.
+ Imposed default one million column, one-million row limits on the image
+ dimensions, and added png_set_user_limits() function to override them.
+ Revised use of PNG_SET_USER_LIMITS_SUPPORTED macro.
+ Fixed wrong cast of returns from png_get_user_width|height_max().
+ Changed some "keep the compiler happy" from empty statements to returns,
+ Revised libpng.txt to remove 1.2.x stuff from the 1.0.x distribution
+
+Version 1.0.16rc2 and 1.2.6rc2 [August 7, 2004]
+ Revised makefile.darwin and makefile.solaris. Removed makefile.macosx.
+ Revised pngtest's png_debug_malloc() to use png_malloc() instead of
+ png_malloc_default() which is not supposed to be exported.
+ Fixed off-by-one error in one of the conversions to PNG_ROWBYTES() in
+ pngpread.c. Bug was introduced in 1.2.6rc1.
+ Fixed bug in RGB to RGBX transformation introduced in 1.2.6rc1.
+ Fixed old bug in RGB to Gray transformation.
+ Fixed problem with 64-bit compilers by casting arguments to abs()
+ to png_int_32.
+ Changed "ln -sf" to "ln -f -s" in three makefiles (solaris, sco, so9).
+ Changed "HANDLE_CHUNK_*" to "PNG_HANDLE_CHUNK_*" (Cosmin)
+ Added "-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)" to 15 *NIX makefiles.
+ Added code to update the row_info->colortype in png_do_read_filler() (MSB).
+
+Version 1.0.16rc3 and 1.2.6rc3 [August 9, 2004]
+ Eliminated use of "abs()" in testing cHRM and gAMA values, to avoid
+ trouble with some 64-bit compilers. Created PNG_OUT_OF_RANGE() macro.
+ Revised documentation of png_set_keep_unknown_chunks().
+ Check handle_as_unknown status in pngpread.c, as in pngread.c previously.
+ Moved "PNG_HANDLE_CHUNK_*" macros out of PNG_INTERNAL section of png.h
+ Added "rim" definitions for CONST4 and CONST6 in pnggccrd.c
+
+Version 1.0.16rc4 and 1.2.6rc4 [August 10, 2004]
+ Fixed mistake in pngtest.c introduced in 1.2.6rc2 (declaration of
+ "pinfo" was out of place).
+
+Version 1.0.16rc5 and 1.2.6rc5 [August 10, 2004]
+ Moved "PNG_HANDLE_CHUNK_*" macros out of PNG_ASSEMBLER_CODE_SUPPORTED
+ section of png.h where they were inadvertently placed in version rc3.
+
+Version 1.2.6 and 1.0.16 [August 15, 2004]
+ Revised pngtest so memory allocation testing is only done when PNG_DEBUG==1.
+
+Version 1.2.7beta1 [August 26, 2004]
+ Removed unused pngasmrd.h file.
+ Removed references to uu.net for archived files. Added references to
+ PNG Spec (second edition) and the PNG ISO/IEC Standard.
+ Added "test-dd" target in 15 makefiles, to run pngtest in DESTDIR.
+ Fixed bug with "optimized window size" in the IDAT datastream, that
+ causes libpng to write PNG files with incorrect zlib header bytes.
+
+Version 1.2.7beta2 [August 28, 2004]
+ Fixed bug with sCAL chunk and big-endian machines (David Munro).
+ Undid new code added in 1.2.6rc2 to update the color_type in
+ png_set_filler().
+ Added png_set_add_alpha() that updates color type.
+
+Version 1.0.17rc1 and 1.2.7rc1 [September 4, 2004]
+ Revised png_set_strip_filler() to not remove alpha if color_type has alpha.
+
+Version 1.2.7 and 1.0.17 [September 12, 2004]
+ Added makefile.hp64
+ Changed projects/msvc/png32ms.def to scripts/png32ms.def in makefile.cygwin
+
+Version 1.2.8beta1 [November 1, 2004]
+ Fixed bug in png_text_compress() that would fail to complete a large block.
+ Fixed bug, introduced in libpng-1.2.7, that overruns a buffer during
+ strip alpha operation in png_do_strip_filler().
+ Added PNG_1_2_X definition in pngconf.h
+ Use #ifdef to comment out png_info_init in png.c and png_read_init in
+ pngread.c (as of 1.3.0)
+
+Version 1.2.8beta2 [November 2, 2004]
+ Reduce color_type to a nonalpha type after strip alpha operation in
+ png_do_strip_filler().
+
+Version 1.2.8beta3 [November 3, 2004]
+ Revised definitions of PNG_MAX_UINT_32, PNG_MAX_SIZE, and PNG_MAXSUM
+
+Version 1.2.8beta4 [November 12, 2004]
+ Fixed (again) definition of PNG_LIBPNG_VER_DLLNUM in png.h (Cosmin).
+ Added PNG_LIBPNG_BUILD_PRIVATE in png.h (Cosmin).
+ Set png_ptr->zstream.data_type to Z_BINARY, to avoid unnecessary detection
+ of data type in deflate (Cosmin).
+ Deprecated but continue to support SPECIALBUILD and PRIVATEBUILD in favor of
+ PNG_LIBPNG_BUILD_SPECIAL_STRING and PNG_LIBPNG_BUILD_PRIVATE_STRING.
+
+Version 1.2.8beta5 [November 20, 2004]
+ Use png_ptr->flags instead of png_ptr->transformations to pass
+ PNG_STRIP_ALPHA info to png_do_strip_filler(), to preserve ABI
+ compatibility.
+ Revised handling of SPECIALBUILD, PRIVATEBUILD,
+ PNG_LIBPNG_BUILD_SPECIAL_STRING and PNG_LIBPNG_BUILD_PRIVATE_STRING.
+
+Version 1.2.8rc1 [November 24, 2004]
+ Moved handling of BUILD macros from pngconf.h to png.h
+ Added definition of PNG_LIBPNG_BASE_TYPE in png.h, inadvertently
+ omitted from beta5.
+ Revised scripts/pngw32.rc
+ Despammed mailing addresses by masking "@" with "at".
+ Inadvertently installed a supposedly faster test version of pngrutil.c
+
+Version 1.2.8rc2 [November 26, 2004]
+ Added two missing "\" in png.h
+ Change tests in pngread.c and pngpread.c to
+ if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
+ png_do_read_transformations(png_ptr);
+
+Version 1.2.8rc3 [November 28, 2004]
+ Reverted pngrutil.c to version libpng-1.2.8beta5.
+ Added scripts/makefile.elf with supporting code in pngconf.h for symbol
+ versioning (John Bowler).
+
+Version 1.2.8rc4 [November 29, 2004]
+ Added projects/visualc7 (Simon-pierre).
+
+Version 1.2.8rc5 [November 29, 2004]
+ Fixed new typo in scripts/pngw32.rc
+
+Version 1.2.8 [December 3, 2004]
+ Removed projects/visualc7, added projects/visualc71.
+
+Version 1.2.9beta1 [February 21, 2006]
+ Initialized some structure members in pngwutil.c to avoid gcc-4.0.0 complaints
+ Revised man page and libpng.txt to make it clear that one should not call
+ png_read_end or png_write_end after png_read_png or png_write_png.
+ Updated references to png-mng-implement mailing list.
+ Fixed an incorrect typecast in pngrutil.c
+ Added PNG_NO_READ_SUPPORTED conditional for making a write-only library.
+ Added PNG_NO_WRITE_INTERLACING_SUPPORTED conditional.
+ Optimized alpha-inversion loops in pngwtran.c
+ Moved test for nonzero gamma outside of png_build_gamma_table() in pngrtran.c
+ Make sure num_trans is <= 256 before copying data in png_set_tRNS().
+ Make sure num_palette is <= 256 before copying data in png_set_PLTE().
+ Interchanged order of write_swap_alpha and write_invert_alpha transforms.
+ Added parentheses in the definition of PNG_LIBPNG_BUILD_TYPE (Cosmin).
+ Optimized zlib window flag (CINFO) in contrib/pngsuite/*.png (Cosmin).
+ Updated scripts/makefile.bc32 for Borland C++ 5.6 (Cosmin).
+ Exported png_get_uint_32, png_save_uint_32, png_get_uint_16, png_save_uint_16,
+ png_get_int_32, png_save_int_32, png_get_uint_31 (Cosmin).
+ Added type cast (png_byte) in png_write_sCAL() (Cosmin).
+ Fixed scripts/makefile.cygwin (Christian Biesinger, Cosmin).
+ Default iTXt support was inadvertently enabled.
+
+Version 1.2.9beta2 [February 21, 2006]
+ Check for png_rgb_to_gray and png_gray_to_rgb read transformations before
+ checking for png_read_dither in pngrtran.c
+ Revised checking of chromaticity limits to accommodate extended RGB
+ colorspace (John Denker).
+ Changed line endings in some of the project files to CRLF, even in the
+ "Unix" tar distributions (Cosmin).
+ Made png_get_int_32 and png_save_int_32 always available (Cosmin).
+ Updated scripts/pngos2.def, scripts/pngw32.def and projects/wince/png32ce.def
+ with the newly exported functions.
+ Eliminated distributions without the "configure" script.
+ Updated INSTALL instructions.
+
+Version 1.2.9beta3 [February 24, 2006]
+ Fixed CRCRLF line endings in contrib/visupng/VisualPng.dsp
+ Made libpng.pc respect EXEC_PREFIX (D. P. Kreil, J. Bowler)
+ Removed reference to pngasmrd.h from Makefile.am
+ Renamed CHANGES to ChangeLog.
+ Renamed LICENSE to COPYING.
+ Renamed ANNOUNCE to NEWS.
+ Created AUTHORS file.
+
+Version 1.2.9beta4 [March 3, 2006]
+ Changed definition of PKGCONFIG from $prefix/lib to $libdir in configure.ac
+ Reverted to filenames LICENSE and ANNOUNCE; removed AUTHORS and COPYING.
+ Removed newline from the end of some error and warning messages.
+ Removed test for sqrt() from configure.ac and configure.
+ Made swap tables in pngtrans.c PNG_CONST (Carlo Bramix).
+ Disabled default iTXt support that was inadvertently enabled in
+ libpng-1.2.9beta1.
+ Added "OS2" to list of systems that don't need underscores, in pnggccrd.c
+ Removed libpng version and date from *.c files.
+
+Version 1.2.9beta5 [March 4, 2006]
+ Removed trailing blanks from source files.
+ Put version and date of latest change in each source file, and changed
+ copyright year accordingly.
+ More cleanup of configure.ac, Makefile.am, and associated scripts.
+ Restored scripts/makefile.elf which was inadvertently deleted.
+
+Version 1.2.9beta6 [March 6, 2006]
+ Fixed typo (RELEASE) in configuration files.
+
+Version 1.2.9beta7 [March 7, 2006]
+ Removed libpng.vers and libpng.sym from libpng12_la_SOURCES in Makefile.am
+ Fixed inconsistent #ifdef's around png_sig_bytes() and png_set_sCAL_s()
+ in png.h.
+ Updated makefile.elf as suggested by debian.
+ Made cosmetic changes to some makefiles, adding LN_SF and other macros.
+ Made some makefiles accept "exec_prefix".
+
+Version 1.2.9beta8 [March 9, 2006]
+ Fixed some "#if defined (..." which should be "#if defined(..."
+ Bug introduced in libpng-1.2.8.
+ Fixed inconsistency in definition of png_default_read_data()
+ Restored blank that was lost from makefile.sggcc "clean" target in beta7.
+ Revised calculation of "current" and "major" for irix in ltmain.sh
+ Changed "mkdir" to "MKDIR_P" in some makefiles.
+ Separated PNG_EXPAND and PNG_EXPAND_tRNS.
+ Added png_set_expand_gray_1_2_4_to_8() and deprecated
+ png_set_gray_1_2_4_to_8() which also expands tRNS to alpha.
+
+Version 1.2.9beta9 [March 10, 2006]
+ Include "config.h" in pngconf.h when available.
+ Added some checks for NULL png_ptr or NULL info_ptr (timeless)
+
+Version 1.2.9beta10 [March 20, 2006]
+ Removed extra CR from contrib/visualpng/VisualPng.dsw (Cosmin)
+ Made pnggccrd.c PIC-compliant (Christian Aichinger).
+ Added makefile.mingw (Wolfgang Glas).
+ Revised pngconf.h MMX checking.
+
+Version 1.2.9beta11 [March 22, 2006]
+ Fixed out-of-order declaration in pngwrite.c that was introduced in beta9
+ Simplified some makefiles by using LIBSO, LIBSOMAJ, and LIBSOVER macros.
+
+Version 1.2.9rc1 [March 31, 2006]
+ Defined PNG_USER_PRIVATEBUILD when including "pngusr.h" (Cosmin).
+ Removed nonsensical assertion check from pngtest.c (Cosmin).
+
+Version 1.2.9 [April 14, 2006]
+ Revised makefile.beos and added "none" selector in ltmain.sh
+
+Version 1.2.10beta1 [April 15, 2006]
+ Renamed "config.h" to "png_conf.h" and revised Makefile.am to add
+ -DPNG_BUILDING_LIBPNG to compile directive, and modified pngconf.h
+ to include png_conf.h only when PNG_BUILDING_LIBPNG is defined.
+
+Version 1.2.10beta2 [April 15, 2006]
+ Manually updated Makefile.in and configure. Changed png_conf.h.in
+ back to config.h.
+
+Version 1.2.10beta3 [April 15, 2006]
+ Change png_conf.h back to config.h in pngconf.h.
+
+Version 1.2.10beta4 [April 16, 2006]
+ Change PNG_BUILDING_LIBPNG to PNG_CONFIGURE_LIBPNG in config/Makefile*.
+
+Version 1.2.10beta5 [April 16, 2006]
+ Added a configure check for compiling assembler code in pnggccrd.c
+
+Version 1.2.10beta6 [April 17, 2006]
+ Revised the configure check for pnggccrd.c
+ Moved -DPNG_CONFIGURE_LIBPNG into @LIBPNG_DEFINES@
+ Added @LIBPNG_DEFINES@ to arguments when building libpng.sym
+
+Version 1.2.10beta7 [April 18, 2006]
+ Change "exec_prefix=$prefix" to "exec_prefix=$(prefix)" in makefiles.
+
+Version 1.2.10rc1 [April 19, 2006]
+ Ensure pngconf.h doesn't define both PNG_USE_PNGGCCRD and PNG_USE_PNGVCRD
+ Fixed "LN_FS" typo in makefile.sco and makefile.solaris.
+
+Version 1.2.10rc2 [April 20, 2006]
+ Added a backslash between -DPNG_CONFIGURE_LIBPNG and -DPNG_NO_ASSEMBLER_CODE
+ in configure.ac and configure
+ Made the configure warning about versioned symbols less arrogant.
+
+Version 1.2.10rc3 [April 21, 2006]
+ Added a note in libpng.txt that png_set_sig_bytes(8) can be used when
+ writing an embedded PNG without the 8-byte signature.
+ Revised makefiles and configure to avoid making links to libpng.so.*
+
+Version 1.2.10 [April 23, 2006]
+ Reverted configure to "rc2" state.
+
+Version 1.2.11beta1 [May 31, 2006]
+ scripts/libpng.pc.in contained "configure" style version info and would
+ not work with makefiles.
+ The shared-library makefiles were linking to libpng.so.0 instead of
+ libpng.so.3 compatibility as the library.
+
+Version 1.2.11beta2 [June 2, 2006]
+ Increased sprintf buffer from 50 to 52 chars in pngrutil.c to avoid
+ buffer overflow.
+ Fixed bug in example.c (png_set_palette_rgb -> png_set_palette_to_rgb)
+
+Version 1.2.11beta3 [June 5, 2006]
+ Prepended "#! /bin/sh" to ltmail.sh and contrib/pngminus/*.sh (Cosmin).
+ Removed the accidental leftover Makefile.in~ (Cosmin).
+ Avoided potential buffer overflow and optimized buffer in
+ png_write_sCAL(), png_write_sCAL_s() (Cosmin).
+ Removed the include directories and libraries from CFLAGS and LDFLAGS
+ in scripts/makefile.gcc (Nelson A. de Oliveira, Cosmin).
+
+Version 1.2.11beta4 [June 6, 2006]
+ Allow zero-length IDAT chunks after the entire zlib datastream, but not
+ after another intervening chunk type.
+
+Version 1.0.19rc1, 1.2.11rc1 [June 13, 2006]
+ Deleted extraneous square brackets from [config.h] in configure.ac
+
+Version 1.0.19rc2, 1.2.11rc2 [June 14, 2006]
+ Added prototypes for PNG_INCH_CONVERSIONS functions to png.h
+ Revised INSTALL and autogen.sh
+ Fixed typo in several makefiles (-W1 should be -Wl)
+ Added typedef for png_int_32 and png_uint_32 on 64-bit systems.
+
+Version 1.0.19rc3, 1.2.11rc3 [June 15, 2006]
+ Removed the new typedefs for 64-bit systems (delay until version 1.4.0)
+ Added one zero element to png_gamma_shift[] array in pngrtran.c to avoid
+ reading out of bounds.
+
+Version 1.0.19rc4, 1.2.11rc4 [June 15, 2006]
+ Really removed the new typedefs for 64-bit systems.
+
+Version 1.0.19rc5, 1.2.11rc5 [June 22, 2006]
+ Removed png_sig_bytes entry from scripts/pngw32.def
+
+Version 1.0.19, 1.2.11 [June 26, 2006]
+ None.
+
+Version 1.0.20, 1.2.12 [June 27, 2006]
+ Really increased sprintf buffer from 50 to 52 chars in pngrutil.c to avoid
+ buffer overflow.
+
+Version 1.2.13beta1 [October 2, 2006]
+ Removed AC_FUNC_MALLOC from configure.ac
+ Work around Intel-Mac compiler bug by setting PNG_NO_MMX_CODE in pngconf.h
+ Change "logical" to "bitwise" throughout documentation.
+ Detect and fix attempt to write wrong iCCP profile length (CVE-2006-7244)
+
+Version 1.0.21, 1.2.13 [November 14, 2006]
+ Fix potential buffer overflow in sPLT chunk handler.
+ Fix Makefile.am to not try to link to noexistent files.
+ Check all exported functions for NULL png_ptr.
+
+Version 1.2.14beta1 [November 17, 2006]
+ Relocated three misplaced tests for NULL png_ptr.
+ Built Makefile.in with automake-1.9.6 instead of 1.9.2.
+ Build configure with autoconf-2.60 instead of 2.59
+
+Version 1.2.14beta2 [November 17, 2006]
+ Added some typecasts in png_zalloc().
+
+Version 1.2.14rc1 [November 20, 2006]
+ Changed "strtod" to "png_strtod" in pngrutil.c
+
+Version 1.0.22, 1.2.14 [November 27, 2006]
+ Added missing "$(srcdir)" in Makefile.am and Makefile.in
+
+Version 1.2.15beta1 [December 3, 2006]
+ Generated configure with autoconf-2.61 instead of 2.60
+ Revised configure.ac to update libpng.pc and libpng-config.
+
+Version 1.2.15beta2 [December 3, 2006]
+ Always export MMX asm functions, just stubs if not building pnggccrd.c
+
+Version 1.2.15beta3 [December 4, 2006]
+ Add "png_bytep" typecast to profile while calculating length in pngwutil.c
+
+Version 1.2.15beta4 [December 7, 2006]
+ Added scripts/CMakeLists.txt
+ Changed PNG_NO_ASSEMBLER_CODE to PNG_NO_MMX_CODE in scripts, like 1.4.0beta
+
+Version 1.2.15beta5 [December 7, 2006]
+ Changed some instances of PNG_ASSEMBLER_* to PNG_MMX_* in pnggccrd.c
+ Revised scripts/CMakeLists.txt
+
+Version 1.2.15beta6 [December 13, 2006]
+ Revised scripts/CMakeLists.txt and configure.ac
+
+Version 1.2.15rc1 [December 18, 2006]
+ Revised scripts/CMakeLists.txt
+
+Version 1.2.15rc2 [December 21, 2006]
+ Added conditional #undef jmpbuf in pngtest.c to undo #define in AIX headers.
+ Added scripts/makefile.nommx
+
+Version 1.2.15rc3 [December 25, 2006]
+ Fixed shared library numbering error that was introduced in 1.2.15beta6.
+
+Version 1.2.15rc4 [December 27, 2006]
+ Fixed handling of rgb_to_gray when png_ptr->color.gray isn't set.
+
+Version 1.2.15rc5 [December 31, 2006]
+ Revised handling of rgb_to_gray.
+
+Version 1.2.15 [January 5, 2007]
+ Added some (unsigned long) typecasts in pngtest.c to avoid printing errors.
+
+Version 1.2.16beta1 [January 6, 2007]
+ Fix bugs in makefile.nommx
+
+Version 1.2.16beta2 [January 16, 2007]
+ Revised scripts/CMakeLists.txt
+
+Version 1.2.16 [January 31, 2007]
+ No changes.
+
+Version 1.2.17beta1 [March 6, 2007]
+ Revised scripts/CMakeLists.txt to install both shared and static libraries.
+ Deleted a redundant line from pngset.c.
+
+Version 1.2.17beta2 [April 26, 2007]
+ Relocated misplaced test for png_ptr == NULL in pngpread.c
+ Change "==" to "&" for testing PNG_RGB_TO_GRAY_ERR & PNG_RGB_TO_GRAY_WARN
+ flags.
+ Changed remaining instances of PNG_ASSEMBLER_* to PNG_MMX_*
+ Added pngerror() when write_IHDR fails in deflateInit2().
+ Added "const" to some array declarations.
+ Mention examples of libpng usage in the libpng*.txt and libpng.3 documents.
+
+Version 1.2.17rc1 [May 4, 2007]
+ No changes.
+
+Version 1.2.17rc2 [May 8, 2007]
+ Moved several PNG_HAVE_* macros out of PNG_INTERNAL because applications
+ calling set_unknown_chunk_location() need them.
+ Changed transformation flag from PNG_EXPAND_tRNS to PNG_EXPAND in
+ png_set_expand_gray_1_2_4_to_8().
+ Added png_ptr->unknown_chunk to hold working unknown chunk data, so it
+ can be free'ed in case of error. Revised unknown chunk handling in
+ pngrutil.c and pngpread.c to use this structure.
+
+Version 1.2.17rc3 [May 8, 2007]
+ Revised symbol-handling in configure script.
+
+Version 1.2.17rc4 [May 10, 2007]
+ Revised unknown chunk handling to avoid storing unknown critical chunks.
+
+Version 1.0.25 [May 15, 2007]
+Version 1.2.17 [May 15, 2007]
+ Added "png_ptr->num_trans=0" before error return in png_handle_tRNS,
+ to eliminate a vulnerability (CVE-2007-2445, CERT VU#684664)
+
+Version 1.0.26 [May 15, 2007]
+Version 1.2.18 [May 15, 2007]
+ Reverted the libpng-1.2.17rc3 change to symbol-handling in configure script
+
+Version 1.2.19beta1 [May 18, 2007]
+ Changed "const static" to "static PNG_CONST" everywhere, mostly undoing
+ change of libpng-1.2.17beta2. Changed other "const" to "PNG_CONST"
+ Changed some handling of unused parameters, to avoid compiler warnings.
+ "if (unused == NULL) return;" becomes "unused = unused".
+
+Version 1.2.19beta2 [May 18, 2007]
+ Only use the valid bits of tRNS value in png_do_expand() (Brian Cartier)
+
+Version 1.2.19beta3 [May 19, 2007]
+ Add some "png_byte" typecasts in png_check_keyword() and write new_key
+ instead of key in zTXt chunk (Kevin Ryde).
+
+Version 1.2.19beta4 [May 21, 2007]
+ Add png_snprintf() function and use it in place of sprint() for improved
+ defense against buffer overflows.
+
+Version 1.2.19beta5 [May 21, 2007]
+ Fixed png_handle_tRNS() to only use the valid bits of tRNS value.
+ Changed handling of more unused parameters, to avoid compiler warnings.
+ Removed some PNG_CONST in pngwutil.c to avoid compiler warnings.
+
+Version 1.2.19beta6 [May 22, 2007]
+ Added some #ifdef PNG_MMX_CODE_SUPPORTED where needed in pngvcrd.c
+ Added a special "_MSC_VER" case that defines png_snprintf to _snprintf
+
+Version 1.2.19beta7 [May 22, 2007]
+ Squelched png_squelch_warnings() in pnggccrd.c and added
+ an #ifdef PNG_MMX_CODE_SUPPORTED block around the declarations that caused
+ the warnings that png_squelch_warnings was squelching.
+
+Version 1.2.19beta8 [May 22, 2007]
+ Removed __MMX__ from test in pngconf.h.
+
+Version 1.2.19beta9 [May 23, 2007]
+ Made png_squelch_warnings() available via PNG_SQUELCH_WARNINGS macro.
+ Revised png_squelch_warnings() so it might work.
+ Updated makefile.sgcc and makefile.solaris; added makefile.solaris-x86.
+
+Version 1.2.19beta10 [May 24, 2007]
+ Resquelched png_squelch_warnings(), use "__attribute__((used))" instead.
+
+Version 1.4.0beta1 [April 20, 2006]
+ Enabled iTXt support (changes png_struct, thus requires so-number change).
+ Cleaned up PNG_ASSEMBLER_CODE_SUPPORTED vs PNG_MMX_CODE_SUPPORTED
+ Eliminated PNG_1_0_X and PNG_1_2_X macros.
+ Removed deprecated functions png_read_init, png_write_init, png_info_init,
+ png_permit_empty_plte, png_set_gray_1_2_4_to_8, png_check_sig, and
+ removed the deprecated macro PNG_MAX_UINT.
+ Moved "PNG_INTERNAL" parts of png.h and pngconf.h into pngintrn.h
+ Removed many WIN32_WCE #ifdefs (Cosmin).
+ Reduced dependency on C-runtime library when on Windows (Simon-Pierre)
+ Replaced sprintf() with png_sprintf() (Simon-Pierre)
+
+Version 1.4.0beta2 [April 20, 2006]
+ Revised makefiles and configure to avoid making links to libpng.so.*
+ Moved some leftover MMX-related defines from pngconf.h to pngintrn.h
+ Updated scripts/pngos2.def, pngw32.def, and projects/wince/png32ce.def
+
+Version 1.4.0beta3 [May 10, 2006]
+ Updated scripts/pngw32.def to comment out MMX functions.
+ Added PNG_NO_GET_INT_32 and PNG_NO_SAVE_INT_32 macros.
+ Scripts/libpng.pc.in contained "configure" style version info and would
+ not work with makefiles.
+ Revised pngconf.h and added pngconf.h.in, so makefiles and configure can
+ pass defines to libpng and applications.
+
+Version 1.4.0beta4 [May 11, 2006]
+ Revised configure.ac, Makefile.am, and many of the makefiles to write
+ their defines in pngconf.h.
+
+Version 1.4.0beta5 [May 15, 2006]
+ Added a missing semicolon in Makefile.am and Makefile.in
+ Deleted extraneous square brackets from configure.ac
+
+Version 1.4.0beta6 [June 2, 2006]
+ Increased sprintf buffer from 50 to 52 chars in pngrutil.c to avoid
+ buffer overflow.
+ Changed sonum from 0 to 1.
+ Removed unused prototype for png_check_sig() from png.h
+
+Version 1.4.0beta7 [June 16, 2006]
+ Exported png_write_sig (Cosmin).
+ Optimized buffer in png_handle_cHRM() (Cosmin).
+ Set pHYs = 2835 x 2835 pixels per meter, and added
+ sCAL = 0.352778e-3 x 0.352778e-3 meters, in pngtest.png (Cosmin).
+ Added png_set_benign_errors(), png_benign_error(), png_chunk_benign_error().
+ Added typedef for png_int_32 and png_uint_32 on 64-bit systems.
+ Added "(unsigned long)" typecast on png_uint_32 variables in printf lists.
+
+Version 1.4.0beta8 [June 22, 2006]
+ Added demonstration of user chunk support in pngtest.c, to support the
+ public sTER chunk and a private vpAg chunk.
+
+Version 1.4.0beta9 [July 3, 2006]
+ Removed ordinals from scripts/pngw32.def and removed png_info_int and
+ png_set_gray_1_2_4_to_8 entries.
+ Inline call of png_get_uint_32() in png_get_uint_31().
+ Use png_get_uint_31() to get vpAg width and height in pngtest.c
+ Removed WINCE and Netware projects.
+ Removed standalone Y2KINFO file.
+
+Version 1.4.0beta10 [July 12, 2006]
+ Eliminated automatic copy of pngconf.h to pngconf.h.in from configure and
+ some makefiles, because it was not working reliably. Instead, distribute
+ pngconf.h.in along with pngconf.h and cause configure and some of the
+ makefiles to update pngconf.h from pngconf.h.in.
+ Added pngconf.h to DEPENDENCIES in Makefile.am
+
+Version 1.4.0beta11 [August 19, 2006]
+ Removed AC_FUNC_MALLOC from configure.ac.
+ Added a warning when writing iCCP profile with mismatched profile length.
+ Patched pnggccrd.c to assemble on x86_64 platforms.
+ Moved chunk header reading into a separate function png_read_chunk_header()
+ in pngrutil.c. The chunk header (len+sig) is now serialized in a single
+ operation (Cosmin).
+ Implemented support for I/O states. Added png_ptr member io_state, and
+ functions png_get_io_chunk_name() and png_get_io_state() in pngget.c
+ (Cosmin).
+ Added png_get_io_chunk_name and png_get_io_state to scripts/*.def (Cosmin).
+ Renamed scripts/pngw32.* to scripts/pngwin.* (Cosmin).
+ Removed the include directories and libraries from CFLAGS and LDFLAGS
+ in scripts/makefile.gcc (Cosmin).
+ Used png_save_uint_32() to set vpAg width and height in pngtest.c (Cosmin).
+ Cast to proper type when getting/setting vpAg units in pngtest.c (Cosmin).
+ Added pngintrn.h to the Visual C++ projects (Cosmin).
+ Removed scripts/list (Cosmin).
+ Updated copyright year in scripts/pngwin.def (Cosmin).
+ Removed PNG_TYPECAST_NULL and used standard NULL consistently (Cosmin).
+ Disallowed the user to redefine png_size_t, and enforced a consistent use
+ of png_size_t across libpng (Cosmin).
+ Changed the type of png_ptr->rowbytes, PNG_ROWBYTES() and friends
+ to png_size_t (Cosmin).
+ Removed png_convert_size() and replaced png_sizeof with sizeof (Cosmin).
+ Removed some unnecessary type casts (Cosmin).
+ Changed prototype of png_get_compression_buffer_size() and
+ png_set_compression_buffer_size() to work with png_size_t instead of
+ png_uint_32 (Cosmin).
+ Removed png_memcpy_check() and png_memset_check() (Cosmin).
+ Fixed a typo (png_byte --> png_bytep) in libpng.3 and libpng.txt (Cosmin).
+ Clarified that png_zalloc() does not clear the allocated memory,
+ and png_zalloc() and png_zfree() cannot be PNGAPI (Cosmin).
+ Renamed png_mem_size_t to png_alloc_size_t, fixed its definition in
+ pngconf.h, and used it in all memory allocation functions (Cosmin).
+ Renamed pngintrn.h to pngpriv.h, added a comment at the top of the file
+ mentioning that the symbols declared in that file are private, and
+ updated the scripts and the Visual C++ projects accordingly (Cosmin).
+ Removed circular references between pngconf.h and pngconf.h.in in
+ scripts/makefile.vc*win32 (Cosmin).
+ Removing trailing '.' from the warning and error messages (Cosmin).
+ Added pngdefs.h that is built by makefile or configure, instead of
+ pngconf.h.in (Glenn).
+ Detect and fix attempt to write wrong iCCP profile length.
+
+Version 1.4.0beta12 [October 19, 2006]
+ Changed "logical" to "bitwise" in the documentation.
+ Work around Intel-Mac compiler bug by setting PNG_NO_MMX_CODE in pngconf.h
+ Add a typecast to stifle compiler warning in pngrutil.c
+
+Version 1.4.0beta13 [November 10, 2006]
+ Fix potential buffer overflow in sPLT chunk handler.
+ Fix Makefile.am to not try to link to noexistent files.
+
+Version 1.4.0beta14 [November 15, 2006]
+ Check all exported functions for NULL png_ptr.
+
+Version 1.4.0beta15 [November 17, 2006]
+ Relocated two misplaced tests for NULL png_ptr.
+ Built Makefile.in with automake-1.9.6 instead of 1.9.2.
+ Build configure with autoconf-2.60 instead of 2.59
+ Add "install: all" in Makefile.am so "configure; make install" will work.
+
+Version 1.4.0beta16 [November 17, 2006]
+ Added a typecast in png_zalloc().
+
+Version 1.4.0beta17 [December 4, 2006]
+ Changed "new_key[79] = '\0';" to "(*new_key)[79] = '\0';" in pngwutil.c
+ Add "png_bytep" typecast to profile while calculating length in pngwutil.c
+
+Version 1.4.0beta18 [December 7, 2006]
+ Added scripts/CMakeLists.txt
+
+Version 1.4.0beta19 [May 16, 2007]
+ Revised scripts/CMakeLists.txt
+ Rebuilt configure and Makefile.in with newer tools.
+ Added conditional #undef jmpbuf in pngtest.c to undo #define in AIX headers.
+ Added scripts/makefile.nommx
+
+Version 1.4.0beta20 [July 9, 2008]
+ Moved several PNG_HAVE_* macros from pngpriv.h to png.h because applications
+ calling set_unknown_chunk_location() need them.
+ Moved several macro definitions from pngpriv.h to pngconf.h
+ Merge with changes to the 1.2.X branch, as of 1.2.30beta04.
+ Deleted all use of the MMX assembler code and Intel-licensed optimizations.
+ Revised makefile.mingw
+
+Version 1.4.0beta21 [July 21, 2008]
+ Moved local array "chunkdata" from pngrutil.c to the png_struct, so
+ it will be freed by png_read_destroy() in case of a read error (Kurt
+ Christensen).
+
+Version 1.4.0beta22 [July 21, 2008]
+ Change "purpose" and "buffer" to png_ptr->chunkdata to avoid memory leaking.
+
+Version 1.4.0beta23 [July 22, 2008]
+ Change "chunkdata = NULL" to "png_ptr->chunkdata = NULL" several places in
+ png_decompress_chunk().
+
+Version 1.4.0beta24 [July 25, 2008]
+ Change all remaining "chunkdata" to "png_ptr->chunkdata" in
+ png_decompress_chunk(), and remove "chunkdata" from parameter list.
+ Put a call to png_check_chunk_name() in png_read_chunk_header().
+ Revised png_check_chunk_name() to reject a name with a lowercase 3rd byte.
+ Removed two calls to png_check_chunk_name() occurring later in the process.
+ Define PNG_NO_ERROR_NUMBERS by default in pngconf.h
+
+Version 1.4.0beta25 [July 30, 2008]
+ Added a call to png_check_chunk_name() in pngpread.c
+ Reverted png_check_chunk_name() to accept a name with a lowercase 3rd byte.
+ Added png_push_have_buffer() function to pngpread.c
+ Eliminated PNG_BIG_ENDIAN_SUPPORTED and associated png_get_* macros.
+ Made inline expansion of png_get_*() optional with PNG_USE_READ_MACROS.
+ Eliminated all PNG_USELESS_TESTS and PNG_CORRECT_PALETTE_SUPPORTED code.
+ Synced contrib directory and configure files with libpng-1.2.30beta06.
+ Eliminated no-longer-used pngdefs.h (but it's still built in the makefiles)
+ Relocated a misplaced "#endif /* PNG_NO_WRITE_FILTER */" in pngwutil.c
+
+Version 1.4.0beta26 [August 4, 2008]
+ Removed png_push_have_buffer() function in pngpread.c. It increased the
+ compiled library size slightly.
+ Changed "-Wall" to "-W -Wall" in the CFLAGS in all makefiles (Cosmin Truta)
+ Declared png_ptr "volatile" in pngread.c and pngwrite.c to avoid warnings.
+ Updated contrib/visupng/cexcept.h to version 2.0.1
+ Added PNG_LITERAL_CHARACTER macros for #, [, and ].
+
+Version 1.4.0beta27 [August 5, 2008]
+ Revised usage of PNG_LITERAL_SHARP in pngerror.c.
+ Moved newline character from individual png_debug messages into the
+ png_debug macros.
+ Allow user to #define their own png_debug, png_debug1, and png_debug2.
+
+Version 1.4.0beta28 [August 5, 2008]
+ Revised usage of PNG_LITERAL_SHARP in pngerror.c.
+ Added PNG_STRING_NEWLINE macro
+
+Version 1.4.0beta29 [August 9, 2008]
+ Revised usage of PNG_STRING_NEWLINE to work on non-ISO compilers.
+ Added PNG_STRING_COPYRIGHT macro.
+ Added non-ISO versions of png_debug macros.
+
+Version 1.4.0beta30 [August 14, 2008]
+ Added premultiplied alpha feature (Volker Wiendl).
+
+Version 1.4.0beta31 [August 18, 2008]
+ Moved png_set_premultiply_alpha from pngtrans.c to pngrtran.c
+ Removed extra crc check at the end of png_handle_cHRM(). Bug introduced
+ in libpng-1.4.0beta20.
+
+Version 1.4.0beta32 [August 19, 2008]
+ Added PNG_WRITE_FLUSH_SUPPORTED block around new png_flush() call.
+ Revised PNG_NO_STDIO version of png_write_flush()
+
+Version 1.4.0beta33 [August 20, 2008]
+ Added png_get|set_chunk_cache_max() to limit the total number of sPLT,
+ text, and unknown chunks that can be stored.
+
+Version 1.4.0beta34 [September 6, 2008]
+ Shortened tIME_string to 29 bytes in pngtest.c
+ Fixed off-by-one error introduced in png_push_read_zTXt() function in
+ libpng-1.2.30beta04/pngpread.c (Harald van Dijk)
+
+Version 1.4.0beta35 [October 6, 2008]
+ Changed "trans_values" to "trans_color".
+ Changed so-number from 0 to 14. Some OS do not like 0.
+ Revised makefile.darwin to fix shared library numbering.
+ Change png_set_gray_1_2_4_to_8() to png_set_expand_gray_1_2_4_to_8()
+ in example.c (debian bug report)
+
+Version 1.4.0beta36 [October 25, 2008]
+ Sync with tEXt vulnerability fix in libpng-1.2.33rc02.
+
+Version 1.4.0beta37 [November 13, 2008]
+ Added png_check_cHRM in png.c and moved checking from pngget.c, pngrutil.c,
+ and pngwrite.c
+
+Version 1.4.0beta38 [November 22, 2008]
+ Added check for zero-area RGB cHRM triangle in png_check_cHRM() and
+ png_check_cHRM_fixed().
+
+Version 1.4.0beta39 [November 23, 2008]
+ Revised png_warning() to write its message on standard output by default
+ when warning_fn is NULL.
+
+Version 1.4.0beta40 [November 24, 2008]
+ Eliminated png_check_cHRM(). Instead, always use png_check_cHRM_fixed().
+ In png_check_cHRM_fixed(), ensure white_y is > 0, and removed redundant
+ check for all-zero coordinates that is detected by the triangle check.
+
+Version 1.4.0beta41 [November 26, 2008]
+ Fixed string vs pointer-to-string error in png_check_keyword().
+ Rearranged test expressions in png_check_cHRM_fixed() to avoid internal
+ overflows.
+ Added PNG_NO_CHECK_cHRM conditional.
+
+Version 1.4.0beta42, 43 [December 1, 2008]
+ Merge png_debug with version 1.2.34beta04.
+
+Version 1.4.0beta44 [December 6, 2008]
+ Removed redundant check for key==NULL before calling png_check_keyword()
+ to ensure that new_key gets initialized and removed extra warning
+ (Merge with version 1.2.34beta05 -- Arvan Pritchard).
+
+Version 1.4.0beta45 [December 9, 2008]
+ In png_write_png(), respect the placement of the filler bytes in an earlier
+ call to png_set_filler() (Jim Barry).
+
+Version 1.4.0beta46 [December 10, 2008]
+ Undid previous change and added PNG_TRANSFORM_STRIP_FILLER_BEFORE and
+ PNG_TRANSFORM_STRIP_FILLER_AFTER conditionals and deprecated
+ PNG_TRANSFORM_STRIP_FILLER (Jim Barry).
+
+Version 1.4.0beta47 [December 15, 2008]
+ Support for dithering was disabled by default, because it has never
+ been well tested and doesn't work very well. The code has not
+ been removed, however, and can be enabled by building libpng with
+ PNG_READ_DITHER_SUPPORTED defined.
+
+Version 1.4.0beta48 [February 14, 2009]
+ Added new exported function png_calloc().
+ Combined several instances of png_malloc(); png_memset() into png_calloc().
+ Removed prototype for png_freeptr() that was added in libpng-1.4.0beta24
+ but was never defined.
+
+Version 1.4.0beta49 [February 28, 2009]
+ Added png_fileno() macro to pngconf.h, used in pngwio.c
+ Corrected order of #ifdef's in png_debug definition in png.h
+ Fixed bug introduced in libpng-1.4.0beta48 with the memset arguments
+ for pcal_params.
+ Fixed order of #ifdef directives in the png_debug defines in png.h
+ (bug introduced in libpng-1.2.34/1.4.0beta29).
+ Revised comments in png_set_read_fn() and png_set_write_fn().
+
+Version 1.4.0beta50 [March 18, 2009]
+ Use png_calloc() instead of png_malloc() to allocate big_row_buf when
+ reading an interlaced file, to avoid a possible UMR.
+ Undid revision of PNG_NO_STDIO version of png_write_flush(). Users
+ having trouble with fflush() can build with PNG_NO_WRITE_FLUSH defined
+ or supply their own flush_fn() replacement.
+ Revised libpng*.txt and png.h documentation about use of png_write_flush()
+ and png_set_write_fn().
+ Removed fflush() from pngtest.c.
+ Added "#define PNG_NO_WRITE_FLUSH" to contrib/pngminim/encoder/pngusr.h
+
+Version 1.4.0beta51 [March 21, 2009]
+ Removed new png_fileno() macro from pngconf.h .
+
+Version 1.4.0beta52 [March 27, 2009]
+ Relocated png_do_chop() ahead of building gamma tables in pngrtran.c
+ This avoids building 16-bit gamma tables unnecessarily.
+ Removed fflush() from pngtest.c.
+ Added "#define PNG_NO_WRITE_FLUSH" to contrib/pngminim/encoder/pngusr.h
+ Added a section on differences between 1.0.x and 1.2.x to libpng.3/libpng.txt
+
+Version 1.4.0beta53 [April 1, 2009]
+ Removed some remaining MMX macros from pngpriv.h
+ Fixed potential memory leak of "new_name" in png_write_iCCP() (Ralph Giles)
+
+Version 1.4.0beta54 [April 13, 2009]
+ Added "ifndef PNG_SKIP_SETJMP_CHECK" block in pngconf.h to allow
+ application code writers to bypass the check for multiple inclusion
+ of setjmp.h when they know that it is safe to ignore the situation.
+ Eliminated internal use of setjmp() in pngread.c and pngwrite.c
+ Reordered ancillary chunks in pngtest.png to be the same as what
+ pngtest now produces, and made some cosmetic changes to pngtest output.
+ Eliminated deprecated png_read_init_3() and png_write_init_3() functions.
+
+Version 1.4.0beta55 [April 15, 2009]
+ Simplified error handling in pngread.c and pngwrite.c by putting
+ the new png_read_cleanup() and png_write_cleanup() functions inline.
+
+Version 1.4.0beta56 [April 25, 2009]
+ Renamed "user_chunk_data" to "my_user_chunk_data" in pngtest.c to suppress
+ "shadowed declaration" warning from gcc-4.3.3.
+ Renamed "gamma" to "png_gamma" in pngset.c to avoid "shadowed declaration"
+ warning about a global "gamma" variable in math.h on some platforms.
+
+Version 1.4.0beta57 [May 2, 2009]
+ Removed prototype for png_freeptr() that was added in libpng-1.4.0beta24
+ but was never defined (again).
+ Rebuilt configure scripts with autoconf-2.63 instead of 2.62
+ Removed pngprefs.h and MMX from makefiles
+
+Version 1.4.0beta58 [May 14, 2009]
+ Changed pngw32.def to pngwin.def in makefile.mingw (typo was introduced
+ in beta57).
+ Clarified usage of sig_bit versus sig_bit_p in example.c (Vincent Torri)
+
+Version 1.4.0beta59 [May 15, 2009]
+ Reformated sources in libpng style (3-space intentation, comment format)
+ Fixed typo in libpng docs (PNG_FILTER_AVE should be PNG_FILTER_AVG)
+ Added sections about the git repository and our coding style to the
+ documentation
+ Relocated misplaced #endif in pngwrite.c, sCAL chunk handler.
+
+Version 1.4.0beta60 [May 19, 2009]
+ Conditionally compile png_read_finish_row() which is not used by
+ progressive readers.
+ Added contrib/pngminim/preader to demonstrate building minimal progressive
+ decoder, based on contrib/gregbook with embedded libpng and zlib.
+
+Version 1.4.0beta61 [May 20, 2009]
+ In contrib/pngminim/*, renamed "makefile.std" to "makefile", since there
+ is only one makefile in those directories, and revised the README files
+ accordingly.
+ More reformatting of comments, mostly to capitalize sentences.
+
+Version 1.4.0beta62 [June 2, 2009]
+ Added "#define PNG_NO_WRITE_SWAP" to contrib/pngminim/encoder/pngusr.h
+ and "define PNG_NO_READ_SWAP" to decoder/pngusr.h and preader/pngusr.h
+ Reformatted several remaining "else statement" into two lines.
+ Added a section to the libpng documentation about using png_get_io_ptr()
+ in configure scripts to detect the presence of libpng.
+
+Version 1.4.0beta63 [June 15, 2009]
+ Revised libpng*.txt and libpng.3 to mention calling png_set_IHDR()
+ multiple times and to specify the sample order in the tRNS chunk,
+ because the ISO PNG specification has a typo in the tRNS table.
+ Changed several PNG_UNKNOWN_CHUNK_SUPPORTED to
+ PNG_HANDLE_AS_UNKNOWN_SUPPORTED, to make the png_set_keep mechanism
+ available for ignoring known chunks even when not saving unknown chunks.
+ Adopted preference for consistent use of "#ifdef" and "#ifndef" versus
+ "#if defined()" and "if !defined()" where possible.
+
+Version 1.4.0beta64 [June 24, 2009]
+ Eliminated PNG_LEGACY_SUPPORTED code.
+ Moved the various unknown chunk macro definitions outside of the
+ PNG_READ|WRITE_ANCILLARY_CHUNK_SUPPORTED blocks.
+
+Version 1.4.0beta65 [June 26, 2009]
+ Added a reference to the libpng license in each file.
+
+Version 1.4.0beta66 [June 27, 2009]
+ Refer to the libpng license instead of the libpng license in each file.
+
+Version 1.4.0beta67 [July 6, 2009]
+ Relocated INVERT_ALPHA within png_read_png() and png_write_png().
+ Added high-level API transform PNG_TRANSFORM_GRAY_TO_RGB.
+ Added an "xcode" project to the projects directory (Alam Arias).
+
+Version 1.4.0beta68 [July 19, 2009]
+ Avoid some tests in filter selection in pngwutil.c
+
+Version 1.4.0beta69 [July 25, 2009]
+ Simplified the new filter-selection test. This runs faster in the
+ common "PNG_ALL_FILTERS" and PNG_FILTER_NONE cases.
+ Removed extraneous declaration from the new call to png_read_gray_to_rgb()
+ (bug introduced in libpng-1.4.0beta67).
+ Fixed up xcode project (Alam Arias)
+ Added a prototype for png_64bit_product() in png.c
+
+Version 1.4.0beta70 [July 27, 2009]
+ Avoid a possible NULL dereference in debug build, in png_set_text_2().
+ (bug introduced in libpng-0.95, discovered by Evan Rouault)
+
+Version 1.4.0beta71 [July 29, 2009]
+ Rebuilt configure scripts with autoconf-2.64.
+
+Version 1.4.0beta72 [August 1, 2009]
+ Replaced *.tar.lzma with *.tar.xz in distribution. Get the xz codec
+ from <http://tukaani.org/xz>.
+
+Version 1.4.0beta73 [August 1, 2009]
+ Reject attempt to write iCCP chunk with negative embedded profile length
+ (JD Chen) (CVE-2009-5063).
+
+Version 1.4.0beta74 [August 8, 2009]
+ Changed png_ptr and info_ptr member "trans" to "trans_alpha".
+
+Version 1.4.0beta75 [August 21, 2009]
+ Removed an extra png_debug() recently added to png_write_find_filter().
+ Fixed incorrect #ifdef in pngset.c regarding unknown chunk support.
+
+Version 1.4.0beta76 [August 22, 2009]
+ Moved an incorrectly located test in png_read_row() in pngread.c
+
+Version 1.4.0beta77 [August 27, 2009]
+ Removed lpXYZ.tar.bz2 (with CRLF), KNOWNBUG, libpng-x.y.z-KNOWNBUG.txt,
+ and the "noconfig" files from the distribution.
+ Moved CMakeLists.txt from scripts into the main libpng directory.
+ Various bugfixes and improvements to CMakeLists.txt (Philip Lowman)
+
+Version 1.4.0beta78 [August 31, 2009]
+ Converted all PNG_NO_* tests to PNG_*_SUPPORTED everywhere except pngconf.h
+ Eliminated PNG_NO_FREE_ME and PNG_FREE_ME_SUPPORTED macros.
+ Use png_malloc plus a loop instead of png_calloc() to initialize
+ row_pointers in png_read_png().
+
+Version 1.4.0beta79 [September 1, 2009]
+ Eliminated PNG_GLOBAL_ARRAYS and PNG_LOCAL_ARRAYS; always use local arrays.
+ Eliminated PNG_CALLOC_SUPPORTED macro and always provide png_calloc().
+
+Version 1.4.0beta80 [September 17, 2009]
+ Removed scripts/libpng.icc
+ Changed typecast of filler from png_byte to png_uint_16 in png_set_filler().
+ (Dennis Gustafsson)
+ Fixed typo introduced in beta78 in pngtest.c ("#if def " should be "#ifdef ")
+
+Version 1.4.0beta81 [September 23, 2009]
+ Eliminated unused PNG_FLAG_FREE_* defines from pngpriv.h
+ Expanded TAB characters in pngrtran.c
+ Removed PNG_CONST from all "PNG_CONST PNG_CHNK" declarations to avoid
+ compiler complaints about doubly declaring things "const".
+ Changed all "#if [!]defined(X)" to "if[n]def X" where possible.
+ Eliminated unused png_ptr->row_buf_size
+
+Version 1.4.0beta82 [September 25, 2009]
+ Moved redundant IHDR checking into new png_check_IHDR() in png.c
+ and report all errors found in the IHDR data.
+ Eliminated useless call to png_check_cHRM() from pngset.c
+
+Version 1.4.0beta83 [September 25, 2009]
+ Revised png_check_IHDR() to eliminate bogus complaint about filter_type.
+
+Version 1.4.0beta84 [September 30, 2009]
+ Fixed some inconsistent indentation in pngconf.h
+ Revised png_check_IHDR() to add a test for width variable less than 32-bit.
+
+Version 1.4.0beta85 [October 1, 2009]
+ Revised png_check_IHDR() again, to check info_ptr members instead of
+ the contents of the returned parameters.
+
+Version 1.4.0beta86 [October 9, 2009]
+ Updated the "xcode" project (Alam Arias).
+ Eliminated a shadowed declaration of "pp" in png_handle_sPLT().
+
+Version 1.4.0rc01 [October 19, 2009]
+ Trivial cosmetic changes.
+
+Version 1.4.0beta87 [October 30, 2009]
+ Moved version 1.4.0 back into beta.
+
+Version 1.4.0beta88 [October 30, 2009]
+ Revised libpng*.txt section about differences between 1.2.x and 1.4.0
+ because most of the new features have now been ported back to 1.2.41
+
+Version 1.4.0beta89 [November 1, 2009]
+ More bugfixes and improvements to CMakeLists.txt (Philip Lowman)
+ Removed a harmless extra png_set_invert_alpha() from pngwrite.c
+ Apply png_user_chunk_cache_max within png_decompress_chunk().
+ Merged libpng-1.2.41.txt with libpng-1.4.0.txt where appropriate.
+
+Version 1.4.0beta90 [November 2, 2009]
+ Removed all remaining WIN32_WCE #ifdefs except those involving the
+ time.h "tm" structure
+
+Version 1.4.0beta91 [November 3, 2009]
+ Updated scripts/pngw32.def and projects/wince/png32ce.def
+ Copied projects/wince/png32ce.def to the scripts directory.
+ Added scripts/makefile.wce
+ Patched ltmain.sh for wince support.
+ Added PNG_CONVERT_tIME_SUPPORTED macro.
+
+Version 1.4.0beta92 [November 4, 2009]
+ Make inclusion of time.h in pngconf.h depend on PNG_CONVERT_tIME_SUPPORTED
+ Make #define PNG_CONVERT_tIME_SUPPORTED depend on PNG_WRITE_tIME_SUPPORTED
+ Revised libpng*.txt to describe differences from 1.2.40 to 1.4.0 (instead
+ of differences from 1.2.41 to 1.4.0)
+
+Version 1.4.0beta93 [November 7, 2009]
+ Added PNG_DEPSTRUCT, PNG_DEPRECATED, PNG_USE_RESULT, PNG_NORETURN, and
+ PNG_ALLOCATED macros to detect deprecated direct access to the
+ png_struct or info_struct members and other deprecated usage in
+ applications (John Bowler).
+ Updated scripts/makefile* to add "-DPNG_CONFIGURE_LIBPNG" to CFLAGS,
+ to prevent warnings about direct access to png structs by libpng
+ functions while building libpng. They need to be tested, especially
+ those using compilers other than gcc.
+ Updated projects/visualc6 and visualc71 with "/d PNG_CONFIGURE_LIBPNG".
+ They should work but still need to be updated to remove
+ references to pnggccrd.c or pngvcrd.c and ASM building.
+ Added README.txt to the beos, cbuilder5, netware, and xcode projects warning
+ that they need to be updated, to remove references to pnggccrd.c and
+ pngvcrd.c and to depend on pngpriv.h
+ Removed three direct references to read_info_ptr members in pngtest.c
+ that were detected by the new PNG_DEPSTRUCT macro.
+ Moved the png_debug macro definitions and the png_read_destroy(),
+ png_write_destroy() and png_far_to_near() prototypes from png.h
+ to pngpriv.h (John Bowler)
+ Moved the synopsis lines for png_read_destroy(), png_write_destroy()
+ png_debug(), png_debug1(), and png_debug2() from libpng.3 to libpngpf.3.
+
+Version 1.4.0beta94 [November 9, 2009]
+ Removed the obsolete, unused pnggccrd.c and pngvcrd.c files.
+ Updated CMakeLists.txt to add "-DPNG_CONFIGURE_LIBPNG" to the definitions.
+ Removed dependency of pngtest.o on pngpriv.h in the makefiles.
+ Only #define PNG_DEPSTRUCT, etc. in pngconf.h if not already defined.
+
+Version 1.4.0beta95 [November 10, 2009]
+ Changed png_check_sig() to !png_sig_cmp() in contrib programs.
+ Added -DPNG_CONFIGURE_LIBPNG to contrib/pngminm/*/makefile
+ Changed png_check_sig() to !png_sig_cmp() in contrib programs.
+ Corrected the png_get_IHDR() call in contrib/gregbook/readpng2.c
+ Changed pngminim/*/gather.sh to stop trying to remove pnggccrd.c and pngvcrd.c
+ Added dependency on pngpriv.h in contrib/pngminim/*/makefile
+
+Version 1.4.0beta96 [November 12, 2009]
+ Renamed scripts/makefile.wce to scripts/makefile.cegcc
+ Revised Makefile.am to use libpng.sys while building libpng.so
+ so that only PNG_EXPORT functions are exported.
+ Removed the deprecated png_check_sig() function/macro.
+ Removed recently removed function names from scripts/*.def
+ Revised pngtest.png to put chunks in the same order written by pngtest
+ (evidently the same change made in libpng-1.0beta54 was lost).
+ Added PNG_PRIVATE macro definition in pngconf.h for possible future use.
+
+Version 1.4.0beta97 [November 13, 2009]
+ Restored pngtest.png to the libpng-1.4.0beta7 version.
+ Removed projects/beos and netware.txt; no one seems to be supporting them.
+ Revised Makefile.in
+
+Version 1.4.0beta98 [November 13, 2009]
+ Added the "xcode" project to zip distributions,
+ Fixed a typo in scripts/pngwin.def introduced in beta97.
+
+Version 1.4.0beta99 [November 14, 2009]
+ Moved libpng-config.in and libpng.pc-configure.in out of the scripts
+ directory, to libpng-config.in and libpng-pc.in, respectively, and
+ modified Makefile.am and configure.ac accordingly. Now "configure"
+ needs nothing from the "scripts" directory.
+ Avoid redefining PNG_CONST in pngconf.h
+
+Version 1.4.0beta100 [November 14, 2009]
+ Removed ASM builds from projects/visualc6 and projects/visualc71
+ Removed scripts/makefile.nommx and makefile.vcawin32
+ Revised CMakeLists.txt to account for new location of libpng-config.in
+ and libpng-pc.in
+ Updated INSTALL to reflect removal and relocation of files.
+
+Version 1.4.0beta101 [November 14, 2009]
+ Restored the binary files (*.jpg, *.png, some project files) that were
+ accidentally deleted from the zip and 7z distributions when the xcode
+ project was added.
+
+Version 1.4.0beta102 [November 18, 2009]
+ Added libpng-config.in and libpng-pc.in to the zip and 7z distributions.
+ Fixed a typo in projects/visualc6/pngtest.dsp, introduced in beta100.
+ Moved descriptions of makefiles and other scripts out of INSTALL into
+ scripts/README.txt
+ Updated the copyright year in scripts/pngwin.rc from 2006 to 2009.
+
+Version 1.4.0beta103 [November 21, 2009]
+ Removed obsolete comments about ASM from projects/visualc71/README_zlib.txt
+ Align row_buf on 16-byte boundary in memory.
+ Restored the PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED guard around the call
+ to png_flush() after png_write_IEND(). See 1.4.0beta32, 1.4.0beta50
+ changes above and 1.2.30, 1.2.30rc01 and rc03 in 1.2.41 CHANGES. Someone
+ needs this feature.
+ Make the 'png_jmpbuf' macro expand to a call that records the correct
+ longjmp function as well as returning a pointer to the setjmp
+ jmp_buf buffer, and marked direct access to jmpbuf 'deprecated'.
+ (John Bowler)
+
+Version 1.4.0beta104 [November 22, 2009]
+ Removed png_longjmp_ptr from scripts/*.def and libpng.3
+ Rebuilt configure scripts with autoconf-2.65
+
+Version 1.4.0beta105 [November 25, 2009]
+ Use fast integer PNG_DIVIDE_BY_255() or PNG_DIVIDE_BY_65535()
+ to accomplish alpha premultiplication when
+ PNG_READ_COMPOSITE_NODIV_SUPPORTED is defined.
+ Changed "/255" to "/255.0" in background calculations to make it clear
+ that the 255 is used as a double.
+
+Version 1.4.0beta106 [November 27, 2009]
+ Removed premultiplied alpha feature.
+
+Version 1.4.0beta107 [December 4, 2009]
+ Updated README
+ Added "#define PNG_NO_PEDANTIC_WARNINGS" in the libpng source files.
+ Removed "-DPNG_CONFIGURE_LIBPNG" from the makefiles and projects.
+ Revised scripts/makefile.netbsd, makefile.openbsd, and makefile.sco
+ to put png.h and pngconf.h in $prefix/include, like the other scripts,
+ instead of in $prefix/include/libpng. Also revised makefile.sco
+ to put them in $prefix/include/libpng15 instead of in
+ $prefix/include/libpng/libpng15.
+
+Version 1.4.0beta108 [December 11, 2009]
+ Removed leftover "-DPNG_CONFIGURE_LIBPNG" from contrib/pngminim/*/makefile
+ Relocated png_do_chop() to its original position in pngrtran.c; the
+ change in version 1.2.41beta08 caused transparency to be handled wrong
+ in some 16-bit datastreams (Yusaku Sugai).
+
+Version 1.4.0beta109 [December 13, 2009]
+ Added "bit_depth" parameter to the private png_build_gamma_table() function.
+ Pass bit_depth=8 to png_build_gamma_table() when bit_depth is 16 but the
+ PNG_16_TO_8 transform has been set, to avoid unnecessary build of 16-bit
+ tables.
+
+Version 1.4.0rc02 [December 20, 2009]
+ Declared png_cleanup_needed "volatile" in pngread.c and pngwrite.c
+
+Version 1.4.0rc03 [December 22, 2009]
+ Renamed libpng-pc.in back to libpng.pc.in and revised CMakeLists.txt
+ (revising the change in 1.4.0beta99)
+
+Version 1.4.0rc04 [December 25, 2009]
+ Swapped PNG_UNKNOWN_CHUNKS_SUPPORTED and PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+ in pngset.c to be consistent with other changes in version 1.2.38.
+
+Version 1.4.0rc05 [December 25, 2009]
+ Changed "libpng-pc.in" to "libpng.pc.in" in configure.ac, configure, and
+ Makefile.in to be consistent with changes in libpng-1.4.0rc03
+
+Version 1.4.0rc06 [December 29, 2009]
+ Reverted the gamma_table changes from libpng-1.4.0beta109.
+ Fixed some indentation errors.
+
+Version 1.4.0rc07 [January 1, 2010]
+ Revised libpng*.txt and libpng.3 about 1.2.x->1.4.x differences.
+ Use png_calloc() instead of png_malloc(); png_memset() in pngrutil.c
+ Update copyright year to 2010.
+
+Version 1.4.0rc08 [January 2, 2010]
+ Avoid deprecated references to png_ptr-io_ptr and png_ptr->error_ptr
+ in pngtest.c
+
+Version 1.4.0 [January 3, 2010]
+ No changes.
+
+Version 1.4.1beta01 [January 8, 2010]
+ Updated CMakeLists.txt for consistent indentation and to avoid an
+ unclosed if-statement warning (Philip Lowman).
+ Revised Makefile.am and Makefile.in to remove references to Y2KINFO,
+ KNOWNBUG, and libpng.la (Robert Schwebel).
+ Revised the makefiles to install the same files and symbolic
+ links as configure, except for libpng.la and libpng14.la.
+ Make png_set|get_compression_buffer_size() available even when
+ PNG_WRITE_SUPPORTED is not enabled.
+ Revised Makefile.am and Makefile.in to simplify their maintenance.
+ Revised scripts/makefile.linux to install a link to libpng14.so.14.1
+
+Version 1.4.1beta02 [January 9, 2010]
+ Revised the rest of the makefiles to install a link to libpng14.so.14.1
+
+Version 1.4.1beta03 [January 10, 2010]
+ Removed png_set_premultiply_alpha() from scripts/*.def
+
+Version 1.4.1rc01 [January 16, 2010]
+ No changes.
+
+Version 1.4.1beta04 [January 23, 2010]
+ Revised png_decompress_chunk() to improve speed and memory usage when
+ decoding large chunks.
+ Added png_set|get_chunk_malloc_max() functions.
+
+Version 1.4.1beta05 [January 26, 2010]
+ Relocated "int k" declaration in pngtest.c to minimize its scope.
+
+Version 1.4.1beta06 [January 28, 2010]
+ Revised png_decompress_chunk() to use a two-pass method suggested by
+ John Bowler.
+
+Version 1.4.1beta07 [February 6, 2010]
+ Folded some long lines in the source files.
+ Added defineable PNG_USER_CHUNK_CACHE_MAX, PNG_USER_CHUNK_MALLOC_MAX,
+ and a PNG_USER_LIMITS_SUPPORTED flag.
+ Eliminated use of png_ptr->irowbytes and reused the slot in png_ptr as
+ png_ptr->png_user_chunk_malloc_max.
+ Revised png_push_save_buffer() to do fewer but larger png_malloc() calls.
+
+Version 1.4.1beta08 [February 6, 2010]
+ Minor cleanup and updating of dates and copyright year.
+
+Version 1.5.0beta01 [February 7, 2010]
+ Moved declaration of png_struct into private pngstruct.h and png_info
+ into pnginfo.h
+
+Version 1.4.1beta09 and 1.5.0beta02 [February 7, 2010]
+ Reverted to original png_push_save_buffer() code.
+
+Version 1.4.1beta10 and 1.5.0beta03 [February 8, 2010]
+ Return allocated "old_buffer" in png_push_save_buffer() before
+ calling png_error(), to avoid a potential memory leak.
+ Updated configure script to use SO number 15.
+
+Version 1.5.0beta04 [February 9, 2010]
+ Removed malformed "incomplete struct declaration" of png_info from png.h
+
+Version 1.5.0beta05 [February 12, 2010]
+ Removed PNG_DEPSTRUCT markup in pngstruct.h and pnginfo.h, and undid the
+ linewrapping that it entailed.
+ Revised comments in pngstruct.h and pnginfo.h and added pointers to
+ the libpng license.
+ Changed PNG_INTERNAL to PNG_EXPOSE_INTERNAL_STRUCTURES
+ Removed the cbuilder5 project, which has not been updated to 1.4.0.
+
+Version 1.4.1beta12 and 1.5.0beta06 [February 14, 2010]
+ Fixed type declaration of png_get_chunk_malloc_max() in pngget.c (Daisuke
+ Nishikawa)
+
+Version 1.5.0beta07 [omitted]
+
+Version 1.5.0beta08 [February 19, 2010]
+ Changed #ifdef PNG_NO_STDIO_SUPPORTED to #ifdef PNG_NO_CONSOLE_IO_SUPPORTED
+ wherever png_snprintf() is used to construct error and warning messages.
+ Noted in scripts/makefile.mingw that it expects to be run under MSYS.
+ Removed obsolete unused MMX-querying support from contrib/gregbook
+ Added exported png_longjmp() function.
+ Removed the AIX redefinition of jmpbuf in png.h
+ Added -D_ALLSOURCE in configure.ac, makefile.aix, and CMakeLists.txt
+ when building on AIX.
+
+Version 1.5.0beta09 [February 19, 2010]
+ Removed -D_ALLSOURCE from configure.ac, makefile.aix, and CMakeLists.txt.
+ Changed the name of png_ptr->jmpbuf to png_ptr->png_jmpbuf in pngstruct.h
+
+Version 1.5.0beta10 [February 25, 2010]
+ Removed unused gzio.c from contrib/pngminim gather and makefile scripts
+ Removed replacement error handlers from contrib/gregbook. Because of
+ the new png_longjmp() function they are no longer needed.
+
+Version 1.5.0beta11 [March 6, 2010]
+ Removed checking for already-included setjmp.h from pngconf.h
+ Fixed inconsistent indentations and made numerous cosmetic changes.
+ Revised the "SEE ALSO" style of libpng.3, libpngpf.3, and png.5
+
+Version 1.5.0beta12 [March 9, 2010]
+ Moved "#include png.h" inside pngpriv.h and removed "#include png.h" from
+ the source files, along with "#define PNG_EXPOSE_INTERNAL_STRUCTURES"
+ and "#define PNG_NO_PEDANTIC_WARNINGS" (John Bowler).
+ Created new pngdebug.h and moved debug definitions there.
+
+Version 1.5.0beta13 [March 10, 2010]
+ Protect pngstruct.h, pnginfo.h, and pngdebug.h from being included twice.
+ Revise the "#ifdef" blocks in png_inflate() so it will compile when neither
+ PNG_USER_CHUNK_MALLOC_MAX nor PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
+ is defined.
+ Removed unused png_measure_compressed_chunk() from pngpriv.h and libpngpf.3
+ Moved the 'config.h' support from pngconf.h to pngpriv.h
+ Removed PNGAPI from the png_longjmp_ptr typedef.
+ Eliminated dependence of pngtest.c on the private pngdebug.h file.
+ Make all png_debug macros into *unterminated* statements or
+ expressions (i.e. a trailing ';' must always be added) and correct
+ the format statements in various png_debug messages.
+
+Version 1.5.0beta14 [March 14, 2010]
+ Removed direct access to png_ptr->io_ptr from the Windows code in pngtest.c
+ Revised Makefile.am to account for recent additions and replacements.
+ Corrected CE and OS/2 DEF files (scripts/png*def) for symbols removed and
+ added ordinal numbers to the Windows DEF file and corrected the duplicated
+ ordinal numbers on CE symbols that are commented out.
+ Added back in export symbols that can be present in the Windows build but
+ are disabled by default.
+ PNG_EXPORT changed to include an 'ordinal' field for DEF file generation.
+ PNG_CALLBACK added to make callback definitions uniform. PNGAPI split
+ into PNGCAPI (base C form), PNGAPI (exports) and PNGCBAPI (callbacks),
+ and appropriate changes made to all files. Cygwin builds re-hinged to
+ allow procedure call standard changes and to remove the need for the DEF
+ file (fixes build on Cygwin).
+ Enabled 'attribute' warnings that are relevant to library APIs and callbacks.
+ Changed rules for generation of the various symbol files and added a new
+ rule for a DEF file (which is also added to the distribution).
+ Updated the symbol file generation to stop it adding spurious spaces
+ to EOL (coming from preprocessor macro expansion). Added a facility
+ to join tokens in the output and rewrite *.dfn to use this.
+ Eliminated scripts/*.def in favor of libpng.def; updated projects/visualc71
+ and removed scripts/makefile.cygwin.
+ Made PNG_BUILD_DLL safe: it can be set whenever a DLL is being built.
+ Removed the include of sys/types.h - apparently unnecessary now on the
+ platforms on which it happened (all but Mac OS and RISC OS).
+ Moved the Mac OS test into pngpriv.h (the only place it is used.)
+
+Version 1.5.0beta15 [March 17, 2010]
+ Added symbols.chk target to Makefile.am to validate the symbols in png.h
+ against the new DEF file scripts/symbols.def.
+ Changed the default DEF file back to pngwin.def.
+ Removed makefile.mingw.
+ Eliminated PNG_NO_EXTERN and PNG_ALL_EXTERN
+
+Version 1.5.0beta16 [April 1, 2010]
+ Make png_text_struct independent of PNG_iTXt_SUPPORTED, so that
+ fields are initialized in all configurations. The READ/WRITE
+ macros (PNG_(READ|WRITE)_iTXt_SUPPORTED) still function as
+ before to disable code to actually read or write iTXt chunks
+ and iTXt_SUPPORTED can be used to detect presence of either
+ read or write support (but it is probably better to check for
+ the one actually required - read or write.)
+ Combined multiple png_warning() calls for a single error.
+ Restored the macro definition of png_check_sig().
+
+Version 1.5.0beta17 [April 17, 2010]
+ Added some "(long)" typecasts to printf calls in png_handle_cHRM().
+ Documented the fact that png_set_dither() was disabled since libpng-1.4.0.
+ Reenabled png_set_dither() but renamed it to png_set_quantize() to reflect
+ more accurately what it actually does. At the same time, renamed
+ the PNG_DITHER_[RED,GREEN_BLUE]_BITS macros to
+ PNG_QUANTIZE_[RED,GREEN,BLUE]_BITS.
+ Added some "(long)" typecasts to printf calls in png_handle_cHRM().
+ Freeze build-time only configuration in the build.
+ In all prior versions of libpng most configuration options
+ controlled by compiler #defines had to be repeated by the
+ application code that used libpng. This patch changes this
+ so that compilation options that can only be changed at build
+ time are frozen in the build. Options that are compiler
+ dependent (and those that are system dependent) are evaluated
+ each time - pngconf.h holds these. Options that can be changed
+ per-file in the application are in png.h. Frozen options are
+ in the new installed header file pnglibconf.h (John Bowler)
+ Removed the xcode project because it has not been updated to work
+ with libpng-1.5.0.
+ Removed the ability to include optional pngusr.h
+
+Version 1.5.0beta18 [April 17, 2010]
+ Restored the ability to include optional pngusr.h
+ Moved replacements for png_error() and png_warning() from the
+ contrib/pngminim project to pngerror.c, for use when warnings or
+ errors are disabled via PNG_NO_WARN or PNG_NO_ERROR_TEXT, to avoid
+ storing unneeded error/warning text.
+ Updated contrib/pngminim project to work with the new pnglibconf.h
+ Added some PNG_NO_* defines to contrib/pngminim/*/pngusr.h to save space.
+
+Version 1.5.0beta19 [April 24, 2010]
+ Added PNG_{READ,WRITE}_INT_FUNCTIONS_SUPPORTED. This allows the functions
+ to read and write ints to be disabled independently of PNG_USE_READ_MACROS,
+ which allows libpng to be built with the functions even though the default
+ is to use the macros - this allows applications to choose at app build
+ time whether or not to use macros (previously impossible because the
+ functions weren't in the default build.)
+ Changed Windows calling convention back to __cdecl for API functions.
+ For Windows/x86 platforms only:
+ __stdcall is no longer needed for Visual Basic, so libpng-1.5.0 uses
+ __cdecl throughout (both API functions and callbacks) on Windows/x86
+ platforms.
+ Replaced visualc6 and visualc71 projects with new vstudio project
+ Relaxed the overly-restrictive permissions of some files.
+
+Version 1.5.0beta20 [April 24, 2010]
+ Relaxed more overly-restrictive permissions of some files.
+
+Version 1.5.0beta21 [April 27, 2010]
+ Removed some unwanted binary bytes and changed CRLF to NEWLINE in the new
+ vstudio project files, and some trivial editing of some files in the
+ scripts directory.
+ Set PNG_NO_READ_BGR, PNG_NO_IO_STATE, and PNG_NO_TIME_RFC1123 in
+ contrib/pngminim/decoder/pngusr.h to make a smaller decoder application.
+
+Version 1.5.0beta22 [April 28, 2010]
+ Fixed dependencies of GET_INT_32 - it does not require READ_INT_FUNCTIONS
+ because it has a macro equivalent.
+ Improved the options.awk script; added an "everything off" option.
+ Revised contrib/pngminim to use the "everything off" option in pngusr.dfa.
+
+Version 1.5.0beta23 [April 29, 2010]
+ Corrected PNG_REMOVED macro to take five arguments.
+ The macro was documented with two arguments (name,ordinal), however
+ the symbol checking .dfn files assumed five arguments. The five
+ argument form seems more useful so it is changed to that.
+ Corrected PNG_UNKNOWN_CHUNKS_SUPPORTED to PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+ in gregbook/readpng2.c
+ Corrected protection of png_get_user_transform_ptr. The API declaration in
+ png.h is removed if both READ and WRITE USER_TRANSFORM are turned off
+ but was left defined in pngtrans.c
+ Added logunsupported=1 to cause pnglibconf.h to document disabled options.
+ This makes the installed pnglibconf.h more readable but causes no
+ other change. The intention is that users of libpng will find it
+ easier to understand if an API they need is missing.
+ Include png_reset_zstream() in png.c only when PNG_READ_SUPPORTED is defined.
+ Removed dummy_inflate.c from contrib/pngminim/encoder
+ Removed contrib/pngminim/*/gather.sh; gathering is now done in the makefile.
+
+Version 1.5.0beta24 [May 7, 2010]
+ Use bitwise "&" instead of arithmetic mod in pngrutil.c calculation of the
+ offset of the png_ptr->rowbuf pointer into png_ptr->big_row_buf.
+ Added more blank lines for readability.
+
+Version 1.5.0beta25 [June 18, 2010]
+ In pngpread.c: png_push_have_row() add check for new_row > height
+ Removed the now-redundant check for out-of-bounds new_row from example.c
+
+Version 1.5.0beta26 [June 18, 2010]
+ In pngpread.c: png_push_process_row() add check for too many rows.
+
+Version 1.5.0beta27 [June 18, 2010]
+ Removed the check added in beta25 as it is now redundant.
+
+Version 1.5.0beta28 [June 20, 2010]
+ Rewrote png_process_IDAT_data to consistently treat extra data as warnings
+ and handle end conditions more cleanly.
+ Removed the new (beta26) check in png_push_process_row().
+
+Version 1.5.0beta29 [June 21, 2010]
+ Revised scripts/options.awk to work on Sunos (but still doesn't work)
+ Added comment to options.awk and contrib/pngminim/*/makefile to try nawk.
+
+Version 1.5.0beta30 [June 22, 2010]
+ Stop memory leak when reading a malformed sCAL chunk.
+
+Version 1.5.0beta31 [June 26, 2010]
+ Revised pngpread.c patch of beta28 to avoid an endless loop.
+ Removed some trailing blanks.
+
+Version 1.5.0beta32 [June 26, 2010]
+ Removed leftover scripts/options.patch and scripts/options.rej
+
+Version 1.5.0beta33 [July 6, 3010]
+ Made FIXED and FLOATING options consistent in the APIs they enable and
+ disable. Corrected scripts/options.awk to handle both command line
+ options and options specified in the .dfa files.
+ Changed char *msg to PNG_CONST char *msg in pngrutil.c
+ Make png_set_sRGB_gAMA_and_cHRM set values using either the fixed or
+ floating point APIs, but not both.
+ Reversed patch to remove error handler when the jmp_buf is stored in the
+ main program structure, not the png_struct.
+ The error handler is needed because the default handler in libpng will
+ always use the jmp_buf in the library control structure; this is never
+ set. The gregbook code is a useful example because, even though it
+ uses setjmp/longjmp, it shows how error handling can be implemented
+ using control mechanisms not directly supported by libpng. The
+ technique will work correctly with mechanisms such as Microsoft
+ Structure Exceptions or C++ exceptions (compiler willing - note that gcc
+ does not by default support interworking of C and C++ error handling.)
+ Reverted changes to call png_longjmp in contrib/gregbook where it is not
+ appropriate. If mainprog->jmpbuf is used by setjmp, then png_longjmp
+ cannot be used.
+ Changed "extern PNG_EXPORT" to "PNG_EXPORT" in png.h (Jan Nijtmans)
+ Changed "extern" to "PNG_EXTERN" in pngpriv.h (except for the 'extern "C" {')
+
+Version 1.5.0beta34 [July 12, 2010]
+ Put #ifndef PNG_EXTERN, #endif around the define PNG_EXTERN in pngpriv.h
+
+Version 1.5.0beta35 [July 24, 2010]
+ Removed some newly-added TAB characters.
+ Added -DNO_PNG_SNPRINTF to CFLAGS in scripts/makefile.dj2
+ Moved the definition of png_snprintf() outside of the enclosing
+ #ifdef blocks in pngconf.h
+
+Version 1.5.0beta36 [July 29, 2010]
+ Patches by John Bowler:
+ Fixed point APIs are now supported throughout (no missing APIs).
+ Internal fixed point arithmetic support exists for all internal floating
+ point operations.
+ sCAL validates the floating point strings it is passed.
+ Safe, albeit rudimentary, Watcom support is provided by PNG_API_RULE==2
+ Two new APIs exist to get the number of passes without turning on the
+ PNG_INTERLACE transform and to get the number of rows in the current
+ pass.
+ A new test program, pngvalid.c, validates the gamma code.
+ Errors in the 16-bit gamma correction (overflows) have been corrected.
+ cHRM chunk testing is done consistently (previously the floating point
+ API bypassed it, because the test really didn't work on FP, now the test
+ is performed on the actual values to be stored in the PNG file so it
+ works in the FP case too.)
+ Most floating point APIs now simply call the fixed point APIs after
+ converting the values to the fixed point form used in the PNG file.
+ The standard headers no longer include zlib.h, which is currently only
+ required for pngstruct.h and can therefore be internal.
+ Revised png_get_int_32 to undo the PNG two's complement representation of
+ negative numbers.
+
+Version 1.5.0beta37 [July 30, 2010]
+ Added a typecast in png_get_int_32() in png.h and pngrutil.h to avoid
+ a compiler warning.
+ Replaced oFFs 0,0 with oFFs -10,20 in pngtest.png
+
+Version 1.5.0beta38 [July 31, 2010]
+ Implemented remaining "_fixed" functions.
+ Corrected a number of recently introduced warnings mostly resulting from
+ safe but uncast assignments to shorter integers. Also added a zlib
+ VStudio release library project because the latest zlib Official Windows
+ build does not include such a thing.
+ Revised png_get_int_16() to be similar to png_get_int_32().
+ Restored projects/visualc71.
+
+Version 1.5.0beta39 [August 2, 2010]
+ VisualC/GCC warning fixes, VisualC build fixes
+ The changes include support for function attributes in VC in addition to
+ those already present in GCC - necessary because without these some
+ warnings are unavoidable. Fixes include signed/unsigned fixes in
+ pngvalid and checks with gcc -Wall -Wextra -Wunused.
+ VC requires function attributes on function definitions as well as
+ declarations, PNG_FUNCTION has been added to enable this and the
+ relevant function definitions changed.
+
+Version 1.5.0beta40 [August 6, 2010]
+ Correct use of _WINDOWS_ in pngconf.h
+ Removed png_mem_ #defines; they are no longer used.
+ Added the sRGB chunk to pngtest.png
+
+Version 1.5.0beta41 [August 11, 2010]
+ Added the cHRM chunk to pngtest.png
+ Don't try to use version-script with cygwin/mingw.
+ Revised contrib/gregbook to work under cygwin/mingw.
+
+Version 1.5.0beta42 [August 18, 2010]
+ Add .dll.a to the list of extensions to be symlinked by Makefile.am (Yaakov)
+ Made all API functions that have const arguments and constant string
+ literal pointers declare them (John Bowler).
+
+Version 1.5.0beta43 [August 20, 2010]
+ Removed spurious tabs, shorten long lines (no source change)
+ Also added scripts/chkfmt to validate the format of all the files that can
+ reasonably be validated (it is suggested to run "make distclean" before
+ checking, because some machine generated files have long lines.)
+ Reformatted the CHANGES file to be more consistent throughout.
+ Made changes to address various issues identified by GCC, mostly
+ signed/unsigned and shortening problems on assignment but also a few
+ difficult to optimize (for GCC) loops.
+ Fixed non-GCC fixed point builds. In png.c a declaration was misplaced
+ in an earlier update. Fixed to declare the auto variables at the head.
+ Use cexcept.h in pngvalid.c.
+
+Version 1.5.0beta44 [August 24, 2010]
+ Updated CMakeLists.txt to use CMAKE_INSTALL_LIBDIR variable; useful for
+ installing libpng in /usr/lib64 (Funda Wang).
+ Revised CMakeLists.txt to put the man pages in share/man/man* not man/man*
+ Revised CMakeLists.txt to make symlinks instead of copies when installing.
+ Changed PNG_LIB_NAME from pngNN to libpngNN in CMakeLists.txt (Philip Lowman)
+ Implemented memory checks within pngvalid
+ Reformatted/rearranged pngvalid.c to assist use of progressive reader.
+ Check interlaced images in pngvalid
+ Clarified pngusr.h comments in pnglibconf.dfa
+ Simplified the pngvalid error-handling code now that cexcept.h is in place.
+ Implemented progressive reader in pngvalid.c for standard tests
+ Implemented progressive read in pngvalid.c gamma tests
+ Turn on progressive reader in pngvalid.c by default and tidy code.
+
+Version 1.5.0beta45 [August 26, 2010]
+ Added an explicit make step to projects/vstudio for pnglibconf.h
+ Also corrected zlib.vcxproj into which Visual Studio had introduced
+ what it calls an "authoring error". The change to make pnglibconf.h
+ simply copies the file; in the future it may actually generate the
+ file from scripts/pnglibconf.dfa as the other build systems do.
+ Changed pngvalid to work when floating point APIs are disabled
+ Renamed the prebuilt scripts/pnglibconf.h to scripts/pnglibconf.h.prebuilt
+ Supply default values for PNG_USER_PRIVATEBUILD and PNG_USER_DLLFNAME_POSTFIX
+ in pngpriv.h in case the user neglected to define them in their pngusr.h
+
+Version 1.5.0beta46 [August 28, 2010]
+ Added new private header files to libpng_sources in CMakeLists.txt
+ Added PNG_READ_16BIT, PNG_WRITE_16BIT, and PNG_16BIT options.
+ Added reference to scripts/pnglibconf.h.prebuilt in the visualc71 project.
+
+Version 1.5.0beta47 [September 11, 2010]
+ Fixed a number of problems with 64-bit compilation reported by Visual
+ Studio 2010 (John Bowler).
+
+Version 1.5.0beta48 [October 4, 2010]
+ Updated CMakeLists.txt (Philip Lowman).
+ Revised autogen.sh to recognize and use $AUTOCONF, $AUTOMAKE, $AUTOHEADER,
+ $AUTOPOINT, $ACLOCAL and $LIBTOOLIZE
+ Fixed problem with symbols creation in Makefile.am which was assuming that
+ all versions of ccp write to standard output by default (Martin Banky). The
+ bug was introduced in libpng-1.2.9beta5.
+ Removed unused mkinstalldirs.
+
+Version 1.5.0beta49 [October 8, 2010]
+ Undid Makefile.am revision of 1.5.0beta48.
+
+Version 1.5.0beta50 [October 14, 2010]
+ Revised Makefile.in to account for mkinstalldirs being removed.
+ Added some "(unsigned long)" typecasts in printf statements in pngvalid.c.
+ Suppressed a compiler warning in png_handle_sPLT().
+ Check for out-of-range text compression mode in png_set_text().
+
+Version 1.5.0beta51 [October 15, 2010]
+ Changed embedded dates to "(PENDING RELEASE) in beta releases (and future
+ rc releases) to minimize the difference between releases.
+
+Version 1.5.0beta52 [October 16, 2010]
+ Restored some of the embedded dates (in png.h, png.c, documentation, etc.)
+
+Version 1.5.0beta53 [October 18, 2010]
+ Updated INSTALL to mention using "make maintainer-clean" and to remove
+ obsolete statement about a custom ltmain.sh
+ Disabled "color-tests" by default in Makefile.am so it will work with
+ automake versions earlier than 1.11.1
+ Use document name "libpng-manual.txt" instead of "libpng-<version>.txt"
+ to simplify version differences.
+ Removed obsolete remarks about setjmp handling from INSTALL.
+ Revised and renamed the typedef in png.h and png.c that was designed
+ to catch library and header mismatch.
+
+Version 1.5.0beta54 [November 10, 2010]
+ Require 48 bytes, not 64 bytes, for big_row_buf in overflow checks.
+ Used a consistent structure for the pngget.c functions.
+
+Version 1.5.0beta55 [November 21, 2010]
+ Revised png_get_uint_32, png_get_int_32, png_get_uint_16 (Cosmin)
+ Moved reading of file signature into png_read_sig (Cosmin)
+ Fixed atomicity of chunk header serialization (Cosmin)
+ Added test for io_state in pngtest.c (Cosmin)
+ Added "#!/bin/sh" at the top of contrib/pngminim/*/gather.sh scripts.
+ Changes to remove gcc warnings (John Bowler)
+ Certain optional gcc warning flags resulted in warnings in libpng code.
+ With these changes only -Wconversion and -Wcast-qual cannot be turned on.
+ Changes are trivial rearrangements of code. -Wconversion is not possible
+ for pngrutil.c (because of the widespread use of += et al on variables
+ smaller than (int) or (unsigned int)) and -Wcast-qual is not possible
+ with pngwio.c and pngwutil.c because the 'write' callback and zlib
+ compression both fail to declare their input buffers with 'const'.
+
+Version 1.5.0beta56 [December 7, 2010]
+ Added the private PNG_UNUSED() macro definition in pngpriv.h.
+ Added some commentary about PNG_EXPORT in png.h and pngconf.h
+ Revised PNG_EXPORT() macro and added PNG_EXPORTA() macro, with the
+ objective of simplifying and improving the cosmetic appearance of png.h.
+ Fixed some incorrect "=" macro names in pnglibconf.dfa
+ Included documentation of changes in 1.5.0 from 1.4.x in libpng-manual.txt
+
+Version 1.5.0beta57 [December 9, 2010]
+ Documented the pngvalid gamma error summary with additional comments and
+ print statements.
+ Improved missing symbol handling in checksym.awk; symbols missing in both
+ the old and new files can now be optionally ignored, treated as errors
+ or warnings.
+ Removed references to pngvcrd.c and pnggccrd.c from the vstudio project.
+ Updated "libpng14" to "libpng15" in the visualc71 project.
+ Enabled the strip16 tests in pngvalid.`
+ Don't display test results (except PASS/FAIL) when running "make test".
+ Instead put them in pngtest-log.txt
+ Added "--with-zprefix=<string>" to configure.ac
+ Updated the prebuilt configuration files to autoconf version 2.68
+
+Version 1.5.0beta58 [December 19, 2010]
+ Fixed interlace image handling and add test cases (John Bowler)
+ Fixed the clean rule in Makefile.am to remove pngtest-log.txt
+ Made minor changes to work around warnings in gcc 3.4
+
+Version 1.5.0rc01 [December 27, 2010]
+ No changes.
+
+Version 1.5.0rc02 [December 27, 2010]
+ Eliminated references to the scripts/*.def files in project/visualc71.
+
+Version 1.5.0rc03 [December 28, 2010]
+ Eliminated scripts/*.def and revised Makefile.am accordingly
+
+Version 1.5.0rc04 [December 29, 2010]
+ Fixed bug in background transformation handling in pngrtran.c (it was
+ looking for the flag in png_ptr->transformations instead of in
+ png_ptr->flags) (David Raymond).
+
+Version 1.5.0rc05 [December 31, 2010]
+ Fixed typo in a comment in CMakeLists.txt (libpng14 => libpng15) (Cosmin)
+
+Version 1.5.0rc06 [January 4, 2011]
+ Changed the new configure option "zprefix=string" to "zlib-prefix=string"
+
+Version 1.5.0rc07 [January 4, 2011]
+ Updated copyright year.
+
+Version 1.5.0 [January 6, 2011]
+ No changes.
+
+version 1.5.1beta01 [January 8, 2011]
+ Added description of png_set_crc_action() to the manual.
+ Added a note in the manual that the type of the iCCP profile was changed
+ from png_charpp to png_bytepp in png_get_iCCP(). This change happened
+ in version 1.5.0beta36 but is not noted in the CHANGES. Similarly,
+ it was changed from png_charpp to png_const_bytepp in png_set_iCCP().
+ Ensure that png_rgb_to_gray ignores palette mapped images, if libpng
+ internally happens to call it with one, and fixed a failure to handle
+ palette mapped images correctly. This fixes CVE-2690.
+
+Version 1.5.1beta02 [January 14, 2011]
+ Fixed a bug in handling of interlaced images (bero at arklinux.org).
+ Updated CMakeLists.txt (Clifford Yapp)
+
+Version 1.5.1beta03 [January 14, 2011]
+ Fixed typecasting of some png_debug() statements (Cosmin)
+
+Version 1.5.1beta04 [January 16, 2011]
+ Updated documentation of png_set|get_tRNS() (Thomas Klausner).
+ Mentioned in the documentation that applications must #include "zlib.h"
+ if they need access to anything in zlib.h, and that a number of
+ macros such as png_memset() are no longer accessible by applications.
+ Corrected pngvalid gamma test "sample" function to access all of the color
+ samples of each pixel, instead of sampling the red channel three times.
+ Prefixed variable names index, div, exp, gamma with "png_" to avoid "shadow"
+ warnings, and (mistakenly) changed png_exp() to exp().
+
+Version 1.5.1beta05 [January 16, 2011]
+ Changed variable names png_index, png_div, png_exp, and png_gamma to
+ char_index, divisor, exp_b10, and gamma_val, respectively, and
+ changed exp() back to png_exp().
+
+Version 1.5.1beta06 [January 20, 2011]
+ Prevent png_push_crc_skip() from hanging while reading an unknown chunk
+ or an over-large compressed zTXt chunk with the progressive reader.
+ Eliminated more GCC "shadow" warnings.
+ Revised png_fixed() in png.c to avoid compiler warning about reaching the
+ end without returning anything.
+
+Version 1.5.1beta07 [January 22, 2011]
+ In the manual, describe the png_get_IHDR() arguments in the correct order.
+ Added const_png_structp and const_png_infop types, and used them in
+ prototypes for most png_get_*() functions.
+
+Version 1.5.1beta08 [January 23, 2011]
+ Added png_get_io_chunk_type() and deprecated png_get_io_chunk_name()
+ Added synopses for the IO_STATE functions and other missing synopses
+ to the manual. Removed the synopses from libpngpf.3 because they
+ were out of date and no longer useful. Better information can be
+ obtained by reading the prototypes and comments in pngpriv.h
+ Attempted to fix cpp on Solaris with S. Studio 12 cc, fix build
+ Added a make macro DFNCPP that is a CPP that will accept the tokens in
+ a .dfn file and adds configure stuff to test for such a CPP. ./configure
+ should fail if one is not available.
+ Corrected const_png_ in png.h to png_const_ to avoid polluting the namespace.
+ Added png_get_current_row_number and png_get_current_pass_number for the
+ benefit of the user transform callback.
+ Added png_process_data_pause and png_process_data_skip for the benefit of
+ progressive readers that need to stop data processing or want to optimize
+ skipping of unread data (e.g., if the reader marks a chunk to be skipped.)
+
+Version 1.5.1beta09 [January 24, 2011]
+ Enhanced pngvalid, corrected an error in gray_to_rgb, corrected doc error.
+ pngvalid contains tests of transforms, which tests are currently disabled
+ because they are incompletely tested. gray_to_rgb was failing to expand
+ the bit depth for smaller bit depth images; this seems to be a long
+ standing error and resulted, apparently, in invalid output
+ (CVE-2011-0408, CERT VU#643140). The documentation did not accurately
+ describe what libpng really does when converting RGB to gray.
+
+Version 1.5.1beta10 [January 27, 2010]
+ Fixed incorrect examples of callback prototypes in the manual, that were
+ introduced in libpng-1.0.0.
+ In addition the order of the png_get_uint macros with respect to the
+ relevant function definitions has been reversed. This helps the
+ preprocessing of the symbol files be more robust. Furthermore, the
+ symbol file preprocessing now uses -DPNG_NO_USE_READ_MACROS even when
+ the library may actually be built with PNG_USE_READ_MACROS; this stops
+ the read macros interfering with the symbol file format.
+ Made the manual, synopses, and function prototypes use the function
+ argument names file_gamma, int_file_gamma, and srgb_intent consistently.
+
+Version 1.5.1beta11 [January 28, 2011]
+ Changed PNG_UNUSED from "param=param;" to "{if(param){}}".
+ Corrected local variable type in new API png_process_data_skip()
+ The type was self-evidently incorrect but only causes problems on 64-bit
+ architectures.
+ Added transform tests to pngvalid and simplified the arguments.
+
+Version 1.5.1rc01 [January 29, 2011]
+ No changes.
+
+Version 1.5.1rc02 [January 31, 2011]
+ Added a request in the manual that applications do not use "png_" or
+ "PNG_" to begin any of their own symbols.
+ Changed PNG_UNUSED to "(void)param;" and updated the commentary in pngpriv.h
+
+Version 1.5.1 [February 3, 2011]
+ No changes.
+
+Version 1.5.2beta01 [February 13, 2011]
+ More -Wshadow fixes for older gcc compilers. Older gcc versions apparently
+ check formal parameters names in function declarations (as well as
+ definitions) to see if they match a name in the global namespace.
+ Revised PNG_EXPORTA macro to not use an empty parameter, to accommodate the
+ old VisualC++ preprocessor.
+ Turned on interlace handling in png_read_png().
+ Fixed gcc pendantic warnings.
+ Handle longjmp in Cygwin.
+ Fixed png_get_current_row_number() in the interlaced case.
+ Cleaned up ALPHA flags and transformations.
+ Implemented expansion to 16 bits.
+
+Version 1.5.2beta02 [February 19, 2011]
+ Fixed mistake in the descriptions of user read_transform and write_transform
+ function prototypes in the manual. The row_info struct is png_row_infop.
+ Reverted png_get_current_row_number() to previous (1.5.2beta01) behavior.
+ Corrected png_get_current_row_number documentation
+ Fixed the read/write row callback documentation.
+ This documents the current behavior, where the callback is called after
+ every row with information pertaining to the next row.
+
+Version 1.5.2beta03 [March 3, 2011]
+ Fixed scripts/makefile.vcwin32
+ Updated contrib/pngsuite/README to add the word "modify".
+ Define PNG_ALLOCATED to blank when _MSC_VER<1300.
+
+Version 1.5.2rc01 [March 19, 2011]
+ Define remaining attributes to blank when MSC_VER<1300.
+ ifdef out mask arrays in pngread.c when interlacing is not supported.
+
+Version 1.5.2rc02 [March 22, 2011]
+ Added a hint to try CPP=/bin/cpp if "cpp -E" fails in scripts/pnglibconf.mak
+ and in contrib/pngminim/*/makefile, eg., on SunOS 5.10, and removed "strip"
+ from the makefiles.
+ Fixed a bug (present since libpng-1.0.7) that makes png_handle_sPLT() fail
+ to compile when PNG_NO_POINTER_INDEXING is defined (Chubanov Kirill)
+
+Version 1.5.2rc03 [March 24, 2011]
+ Don't include standard header files in png.h while building the symbol table,
+ to avoid cpp failure on SunOS (introduced PNG_BUILDING_SYMBOL_TABLE macro).
+
+Version 1.5.2 [March 31, 2011]
+ No changes.
+
+Version 1.5.3beta01 [April 1, 2011]
+ Re-initialize the zlib compressor before compressing non-IDAT chunks.
+ Added API functions (png_set_text_compression_level() and four others) to
+ set parameters for zlib compression of non-IDAT chunks.
+
+Version 1.5.3beta02 [April 3, 2011]
+ Updated scripts/symbols.def with new API functions.
+ Only compile the new zlib re-initializing code when text or iCCP is
+ supported, using PNG_WRITE_COMPRESSED_TEXT_SUPPORTED macro.
+ Improved the optimization of the zlib CMF byte (see libpng-1.2.6beta03).
+ Optimize the zlib CMF byte in non-IDAT compressed chunks
+
+Version 1.5.3beta03 [April 16, 2011]
+ Fixed gcc -ansi -pedantic compile. A strict ANSI system does not have
+ snprintf, and the "__STRICT_ANSI__" detects that condition more reliably
+ than __STDC__ (John Bowler).
+ Removed the PNG_PTR_NORETURN attribute because it too dangerous. It tells
+ the compiler that a user supplied callback (the error handler) does not
+ return, yet there is no guarantee in practice that the application code
+ will correctly implement the error handler because the compiler only
+ issues a warning if there is a mistake (John Bowler).
+ Removed the no-longer-used PNG_DEPSTRUCT macro.
+ Updated the zlib version to 1.2.5 in the VStudio project.
+ Fixed 64-bit builds where png_uint_32 is smaller than png_size_t in
+ pngwutil.c (John Bowler).
+ Fixed bug with stripping the filler or alpha channel when writing, that
+ was introduced in libpng-1.5.2beta01 (bug report by Andrew Church).
+
+Version 1.5.3beta04 [April 27, 2011]
+ Updated pngtest.png with the new zlib CMF optimization.
+ Cleaned up conditional compilation code and of background/gamma handling
+ Internal changes only except a new option to avoid compiling the
+ png_build_grayscale_palette API (which is not used at all internally.)
+ The main change is to move the transform tests (READ_TRANSFORMS,
+ WRITE_TRANSFORMS) up one level to the caller of the APIs. This avoids
+ calls to spurious functions if all transforms are disabled and slightly
+ simplifies those functions. Pngvalid modified to handle this.
+ A minor change is to stop the strip_16 and expand_16 interfaces from
+ disabling each other; this allows the future alpha premultiplication
+ code to use 16-bit intermediate values while still producing 8-bit output.
+ png_do_background and png_do_gamma have been simplified to take a single
+ pointer to the png_struct rather than pointers to every item required
+ from the png_struct. This makes no practical difference to the internal
+ code.
+ A serious bug in the pngvalid internal routine 'standard_display_init' has
+ been fixed - this failed to initialize the red channel and accidentally
+ initialized the alpha channel twice.
+ Changed png_struct jmp_buf member name from png_jmpbuf to tmp_jmpbuf to
+ avoid a possible clash with the png_jmpbuf macro on some platforms.
+
+Version 1.5.3beta05 [May 6, 2011]
+ Added the "_POSIX_SOURCE" feature test macro to ensure libpng sees the
+ correct API. _POSIX_SOURCE is defined in pngpriv.h, pngtest.c and
+ pngvalid.c to ensure that POSIX conformant systems disable non-POSIX APIs.
+ Removed png_snprintf and added formatted warning messages. This change adds
+ internal APIs to allow png_warning messages to have parameters without
+ requiring the host OS to implement snprintf. As a side effect the
+ dependency of the tIME-supporting RFC1132 code on stdio is removed and
+ PNG_NO_WARNINGS does actually work now.
+ Pass "" instead of '\0' to png_default_error() in png_err(). This mistake
+ was introduced in libpng-1.2.20beta01. This fixes CVE-2011-2691.
+ Added PNG_WRITE_OPTIMIZE_CMF_SUPPORTED macro to make the zlib "CMF" byte
+ optimization configureable.
+ IDAT compression failed if preceded by a compressed text chunk (bug
+ introduced in libpng-1.5.3beta01-02). This was because the attempt to
+ reset the zlib stream in png_write_IDAT happened after the first IDAT
+ chunk had been deflated - much too late. In this change internal
+ functions were added to claim/release the z_stream and, hopefully, make
+ the code more robust. Also deflateEnd checking is added - previously
+ libpng would ignore an error at the end of the stream.
+
+Version 1.5.3beta06 [May 8, 2011]
+ Removed the -D_ALL_SOURCE from definitions for AIX in CMakeLists.txt
+ Implemented premultiplied alpha support: png_set_alpha_mode API
+
+Version 1.5.3beta07 [May 11, 2011]
+ Added expand_16 support to the high level interface.
+ Added named value and 'flag' gamma support to png_set_gamma. Made a minor
+ change from the previous (unreleased) ABI/API to hide the exact value used
+ for Macs - it's not a good idea to embed this in the ABI!
+ Moved macro definitions for PNG_HAVE_IHDR, PNG_HAVE_PLTE, and PNG_AFTER_IDAT
+ from pngpriv.h to png.h because they must be visible to applications
+ that call png_set_unknown_chunks().
+ Check for up->location !PNG_AFTER_IDAT when writing unknown chunks
+ before IDAT.
+
+Version 1.5.3beta08 [May 16, 2011]
+ Improved "pngvalid --speed" to exclude more of pngvalid from the time.
+ Documented png_set_alpha_mode(), other changes in libpng.3/libpng-manual.txt
+ The cHRM chunk now sets the defaults for png_set_rgb_to_gray() (when negative
+ parameters are supplied by the caller), while in the absence of cHRM
+ sRGB/Rec 709 values are still used. This introduced a divide-by-zero
+ bug in png_handle_cHRM().
+ The bKGD chunk no longer overwrites the background value set by
+ png_set_background(), allowing the latter to be used before the file
+ header is read. It never performed any useful function to override
+ the default anyway.
+ Added memory overwrite and palette image checks to pngvalid.c
+ Previously palette image code was poorly checked. Since the transformation
+ code has a special palette path in most cases this was a severe weakness.
+ Minor cleanup and some extra checking in pngrutil.c and pngrtran.c. When
+ expanding an indexed image, always expand to RGBA if transparency is
+ present.
+
+Version 1.5.3beta09 [May 17, 2011]
+ Reversed earlier 1.5.3 change of transformation order; move png_expand_16
+ back where it was. The change doesn't work because it requires 16-bit
+ gamma tables when the code only generates 8-bit ones. This fails
+ silently; the libpng code just doesn't do any gamma correction. Moving
+ the tests back leaves the old, inaccurate, 8-bit gamma calculations, but
+ these are clearly better than none!
+
+Version 1.5.3beta10 [May 20, 2011]
+
+ png_set_background() and png_expand_16() did not work together correctly.
+ This problem is present in 1.5.2; if png_set_background is called with
+ need_expand false and the matching 16 bit color libpng erroneously just
+ treats it as an 8-bit color because of where png_do_expand_16 is in the
+ transform list. This simple fix reduces the supplied colour to 8-bits,
+ so it gets smashed, but this is better than the current behavior.
+ Added tests for expand16, more fixes for palette image tests to pngvalid.
+ Corrects the code for palette image tests and disables attempts to
+ validate palette colors.
+
+Version 1.5.3rc01 [June 3, 2011]
+ No changes.
+
+Version 1.5.3rc02 [June 8, 2011]
+ Fixed uninitialized memory read in png_format_buffer() (Bug report by
+ Frank Busse, CVE-2011-2501, related to CVE-2004-0421).
+
+Version 1.5.3beta11 [June 11, 2011]
+ Fixed png_handle_sCAL which is broken in 1.5. This fixes CVE 2011-2692.
+ Added sCAL to pngtest.png
+ Revised documentation about png_set_user_limits() to say that it also affects
+ png writing.
+ Revised handling of png_set_user_limits() so that it can increase the
+ limit beyond the PNG_USER_WIDTH|HEIGHT_MAX; previously it could only
+ reduce it.
+ Make the 16-to-8 scaling accurate. Dividing by 256 with no rounding is
+ wrong (high by one) 25% of the time. Dividing by 257 with rounding is
+ wrong in 128 out of 65536 cases. Getting the right answer all the time
+ without division is easy.
+ Added "_SUPPORTED" to the PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION macro.
+ Added projects/owatcom, an IDE project for OpenWatcom to replace
+ scripts/makefile.watcom. This project works with OpenWatcom 1.9. The
+ IDE autogenerates appropriate makefiles (libpng.mk) for batch processing.
+ The project is configurable, unlike the Visual Studio project, so long
+ as the developer has an awk.
+ Changed png_set_gAMA to limit the gamma value range so that the inverse
+ of the stored value cannot overflow the fixed point representation,
+ and changed other things OpenWatcom warns about.
+ Revised pngvalid.c to test PNG_ALPHA_MODE_SUPPORTED correctly. This allows
+ pngvalid to build when ALPHA_MODE is not supported, which is required if
+ it is to build on libpng 1.4.
+ Removed string/memory macros that are no longer used and are not
+ necessarily fully supportable, particularly png_strncpy and png_snprintf.
+ Added log option to pngvalid.c and attempted to improve gamma messages.
+
+Version 1.5.3 [omitted]
+ People found the presence of a beta release following an rc release
+ to be confusing; therefore we bump the version to libpng-1.5.4beta01
+ and there will be no libpng-1.5.3 release.
+
+Version 1.5.4beta01 [June 14, 2011]
+ Made it possible to undefine PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
+ to get the same (inaccurate) output as libpng-1.5.2 and earlier.
+ Moved definitions of PNG_HAVE_IHDR, PNG_AFTER_IDAT, and PNG_HAVE_PLTE
+ outside of an unknown-chunk block in png.h because they are also
+ needed for other uses.
+
+Version 1.5.4beta02 [June 14, 2011]
+ Fixed and clarified LEGACY 16-to-8 scaling code.
+ Added png_set_chop_16() API, to match inaccurate results from previous
+ libpng versions.
+ Removed the ACCURATE and LEGACY options (they are no longer useable)
+ Use the old scaling method for background if png_set_chop_16() was
+ called.
+ Made png_set_chop_16() API removeable by disabling PNG_CHOP_16_TO_8_SUPPORTED
+
+Version 1.5.4beta03 [June 15, 2011]
+ Fixed a problem in png_do_expand_palette() exposed by optimization in
+ 1.5.3beta06
+ Also removed a spurious and confusing "trans" member ("trans") from png_info.
+ The palette expand optimization prevented expansion to an intermediate RGBA
+ form if tRNS was present but alpha was marked to be stripped; this exposed
+ a check for tRNS in png_do_expand_palette() which is inconsistent with the
+ code elsewhere in libpng.
+ Correction to the expand_16 code; removed extra instance of
+ png_set_scale_16_to_8 from pngpriv.h
+
+Version 1.5.4beta04 [June 16, 2011]
+ Added a missing "#ifdef PNG_READ_BACKGROUND_SUPPORTED/#endif" in pngrtran.c
+ Added PNG_TRANSFORM_CHOP_16 to the high-level read transforms.
+ Made PNG_READ_16_TO_8_ACCURATE_SCALE configurable again. If this is
+ not enabled, png_set_strip_16() and png_do_scale_16_to_8() aren't built.
+ Revised contrib/visupng, gregbook, and pngminim to demonstrate chop_16_to_8
+
+Version 1.5.4beta05 [June 16, 2011]
+ Renamed png_set_strip_16() to png_set_scale_16() and renamed
+ png_set_chop_16() to png_set_strip(16) in an attempt to minimize the
+ behavior changes between libpng14 and libpng15.
+
+Version 1.5.4beta06 [June 18, 2011]
+ Fixed new bug that was causing both strip_16 and scale_16 to be applied.
+
+Version 1.5.4beta07 [June 19, 2011]
+ Fixed pngvalid, simplified macros, added checking for 0 in sCAL.
+ The ACCURATE scale macro is no longer defined in 1.5 - call the
+ png_scale_16_to_8 API. Made sure that PNG_READ_16_TO_8 is still defined
+ if the png_strip_16_to_8 API is present. png_check_fp_number now
+ maintains some state so that positive, negative and zero values are
+ identified. sCAL uses these to be strictly spec conformant.
+
+Version 1.5.4beta08 [June 23, 2011]
+ Fixed pngvalid if ACCURATE_SCALE is defined.
+ Updated scripts/pnglibconf.h.prebuilt.
+
+Version 1.5.4rc01 [June 30, 2011]
+ Define PNG_ALLOCATED to "restrict" only if MSC_VER >= 1400.
+
+Version 1.5.4 [July 7, 2011]
+ No changes.
+
+Version 1.5.5beta01 [July 13, 2011]
+ Fixed some typos and made other minor changes in the manual.
+ Updated contrib/pngminus/makefile.std (Samuli Souminen)
+
+Version 1.5.5beta02 [July 14, 2011]
+ Revised Makefile.am and Makefile.in to look in the right directory for
+ pnglibconf.h.prebuilt
+
+Version 1.5.5beta03 [July 27, 2011]
+ Enabled compilation with g++ compiler. This compiler does not recognize
+ the file extension, so it always compiles with C++ rules. Made minor
+ changes to pngrutil.c to cast results where C++ expects it but C does not.
+ Minor editing of libpng.3 and libpng-manual.txt.
+
+Version 1.5.5beta04 [July 29, 2011]
+ Revised CMakeLists.txt (Clifford Yapp)
+ Updated commentary about the png_rgb_to_gray() default coefficients
+ in the manual and in pngrtran.c
+
+Version 1.5.5beta05 [August 17, 2011]
+ Prevent unexpected API exports from non-libpng DLLs on Windows. The "_DLL"
+ is removed from the test of whether a DLL is being built (this erroneously
+ caused the libpng APIs to be marked as DLL exports in static builds under
+ Microsoft Visual Studio). Almost all of the libpng building configuration
+ is moved from pngconf.h to pngpriv.h, but PNG_DLL_EXPORT remains in
+ pngconf.h, though, so that it is colocated with the import definition (it
+ is no longer used anywhere in the installed headers). The VStudio project
+ definitions have been cleaned up: "_USRDLL" has been removed from the
+ static library builds (this was incorrect), and PNG_USE_DLL has been added
+ to pngvalid to test the functionality (pngtest does not supply it,
+ deliberately). The spurious "_EXPORTS" has been removed from the
+ libpng build (all these errors were a result of copy/paste between project
+ configurations.)
+ Added new types and internal functions for CIE RGB end point handling to
+ pngpriv.h (functions yet to be implemented).
+
+Version 1.5.5beta06 [August 26, 2011]
+ Ensure the CMAKE_LIBRARY_OUTPUT_DIRECTORY is set in CMakeLists.txt
+ (Clifford Yap)
+ Fixes to rgb_to_gray and cHRM XYZ APIs (John Bowler):
+ The rgb_to_gray code had errors when combined with gamma correction.
+ Some pixels were treated as true grey when they weren't and such pixels
+ and true grey ones were not gamma corrected (the original value of the
+ red component was used instead). APIs to get and set cHRM using color
+ space end points have been added and the rgb_to_gray code that defaults
+ based on cHRM, and the divide-by-zero bug in png_handle_cHRM (CERT
+ VU#477046, CVE-2011-3328, introduced in 1.5.4) have been corrected.
+ A considerable number of tests has been added to pngvalid for the
+ rgb_to_gray transform.
+ Arithmetic errors in rgb_to_gray whereby the calculated gray value was
+ truncated to the bit depth rather than rounded have been fixed except in
+ the 8-bit non-gamma-corrected case (where consistency seems more important
+ than correctness.) The code still has considerable inaccuracies in the
+ 8-bit case because 8-bit linear arithmetic is used.
+
+Version 1.5.5beta07 [September 7, 2011]
+ Added "$(ARCH)" option to makefile.darwin
+ Added SunOS support to configure.ac and Makefile.am
+ Changed png_chunk_benign_error() to png_warning() in png.c, in
+ png_XYZ_from_xy_checked().
+
+Version 1.5.5beta08 [September 10, 2011]
+ Fixed 64-bit compilation errors (gcc). The errors fixed relate
+ to conditions where types that are 32 bits in the GCC 32-bit
+ world (uLong and png_size_t) become 64 bits in the 64-bit
+ world. This produces potential truncation errors which the
+ compiler correctly flags.
+ Relocated new HAVE_SOLARIS_LD definition in configure.ac
+ Constant changes for 64-bit compatibility (removal of L suffixes). The
+ 16-bit cases still use "L" as we don't have a 16-bit test system.
+
+Version 1.5.5rc01 [September 15, 2011]
+ Removed "L" suffixes in pngpriv.h
+
+Version 1.5.5 [September 22, 2011]
+ No changes.
+
+Version 1.5.6beta01 [September 22, 2011]
+ Fixed some 64-bit type conversion warnings in pngrtran.c
+ Moved row_info from png_struct to a local variable.
+ The various interlace mask arrays have been made into arrays of
+ bytes and made PNG_CONST and static (previously some arrays were
+ marked PNG_CONST and some weren't).
+ Additional checks have been added to the transform code to validate the
+ pixel depths after the transforms on both read and write.
+ Removed some redundant code from pngwrite.c, in png_destroy_write_struct().
+ Changed chunk reading/writing code to use png_uint_32 instead of png_byte[4].
+ This removes the need to allocate temporary strings for chunk names on
+ the stack in the read/write code. Unknown chunk handling still uses the
+ string form because this is exposed in the API.
+
+Version 1.5.6beta02 [September 26, 2011]
+ Added a note in the manual the png_read_update_info() must be called only
+ once with a particular info_ptr.
+ Fixed a typo in the definition of the new PNG_STRING_FROM_CHUNK(s,c) macro.
+
+Version 1.5.6beta03 [September 28, 2011]
+ Revised test-pngtest.sh to report FAIL when pngtest fails.
+ Added "--strict" option to pngtest, to report FAIL when the failure is
+ only because the resulting valid files are different.
+ Revised CMakeLists.txt to work with mingw and removed some material from
+ CMakeLists.txt that is no longer useful in libpng-1.5.
+
+Version 1.5.6beta04 [October 5, 2011]
+ Fixed typo in Makefile.in and Makefile.am ("-M Wl" should be "-M -Wl")."
+
+Version 1.5.6beta05 [October 12, 2011]
+ Speed up png_combine_row() for interlaced images. This reduces the generality
+ of the code, allowing it to be optimized for Adam7 interlace. The masks
+ passed to png_combine_row() are now generated internally, avoiding
+ some code duplication and localizing the interlace handling somewhat.
+ Align png_struct::row_buf - previously it was always unaligned, caused by
+ a bug in the code that attempted to align it; the code needs to subtract
+ one from the pointer to take account of the filter byte prepended to
+ each row.
+ Optimized png_combine_row() when rows are aligned. This gains a small
+ percentage for 16-bit and 32-bit pixels in the typical case where the
+ output row buffers are appropriately aligned. The optimization was not
+ previously possible because the png_struct buffer was always misaligned.
+ Fixed bug in png_write_chunk_header() debug print, introduced in 1.5.6beta01.
+
+Version 1.5.6beta06 [October 17, 2011]
+ Removed two redundant tests for unitialized row.
+ Fixed a relatively harmless memory overwrite in compressed text writing
+ with a 1 byte zlib buffer.
+ Add ability to call png_read_update_info multiple times to pngvalid.c.
+ Fixes for multiple calls to png_read_update_info. These fixes attend to
+ most of the errors revealed in pngvalid, however doing the gamma work
+ twice results in inaccuracies that can't be easily fixed. There is now
+ a warning in the code if this is going to happen.
+ Turned on multiple png_read_update_info in pngvalid transform tests.
+ Prevent libpng from overwriting unused bits at the end of the image when
+ it is not byte aligned, while reading. Prior to libpng-1.5.6 libpng would
+ overwrite the partial byte at the end of each row if the row width was not
+ an exact multiple of 8 bits and the image is not interlaced.
+
+Version 1.5.6beta07 [October 21, 2011]
+ Made png_ptr->prev_row an aligned pointer into png_ptr->big_prev_row
+ (Mans Rullgard).
+
+Version 1.5.6rc01 [October 26, 2011]
+ Changed misleading "Missing PLTE before cHRM" warning to "Out of place cHRM"
+
+Version 1.5.6rc02 [October 27, 2011]
+ Added LSR() macro to defend against buggy compilers that evaluate non-taken
+ code branches and complain about out-of-range shifts.
+
+Version 1.5.6rc03 [October 28, 2011]
+ Renamed the LSR() macro to PNG_LSR() and added PNG_LSL() macro.
+ Fixed compiler warnings with Intel and MSYS compilers. The logical shift
+ fix for Microsoft Visual C is required by other compilers, so this
+ enables that fix for all compilers when using compile-time constants.
+ Under MSYS 'byte' is a name declared in a system header file, so we
+ changed the name of a local variable to avoid the warnings that result.
+ Added #define PNG_ALIGN_TYPE PNG_ALIGN_NONE to contrib/pngminim/*/pngusr.h
+
+Version 1.5.6 [November 3, 2011]
+ No changes.
+
+Version 1.5.7beta01 [November 4, 2011]
+ Added support for ARM processor, when decoding all PNG up-filtered rows
+ and any other-filtered rows with 3 or 4 bytes per pixel (Mans Rullgard).
+ Fixed bug in pngvalid on early allocation failure; fixed type cast in
+ pngmem.c; pngvalid would attempt to call png_error() if the allocation
+ of a png_struct or png_info failed. This would probably have led to a
+ crash. The pngmem.c implementation of png_malloc() included a cast
+ to png_size_t which would fail on large allocations on 16-bit systems.
+ Fix for the preprocessor of the Intel C compiler. The preprocessor
+ splits adjacent @ signs with a space; this changes the concatentation
+ token from @-@-@ to PNG_JOIN; that should work with all compiler
+ preprocessors.
+ Paeth filter speed improvements from work by Siarhei Siamashka. This
+ changes the 'Paeth' reconstruction function to improve the GCC code
+ generation on x86. The changes are only part of the suggested ones;
+ just the changes that definitely improve speed and remain simple.
+ The changes also slightly increase the clarity of the code.
+
+Version 1.5.7beta02 [November 11, 2011]
+ Check compression_type parameter in png_get_iCCP and remove spurious
+ casts. The compression_type parameter is always assigned to, so must
+ be non-NULL. The cast of the profile length potentially truncated the
+ value unnecessarily on a 16-bit int system, so the cast of the (byte)
+ compression type to (int) is specified by ANSI-C anyway.
+ Fixed FP division by zero in pngvalid.c; the 'test_pixel' code left
+ the sBIT fields in the test pixel as 0, which resulted in a floating
+ point division by zero which was irrelevant but causes systems where
+ FP exceptions cause a crash. Added code to pngvalid to turn on FP
+ exceptions if the appropriate glibc support is there to ensure this is
+ tested in the future.
+ Updated scripts/pnglibconf.mak and scripts/makefile.std to handle the
+ new PNG_JOIN macro.
+ Added versioning to pnglibconf.h comments.
+ Simplified read/write API initial version; basic read/write tested on
+ a variety of images, limited documentation (in the header file.)
+ Installed more accurate linear to sRGB conversion tables. The slightly
+ modified tables reduce the number of 16-bit values that
+ convert to an off-by-one 8-bit value. The "makesRGB.c" code that was used
+ to generate the tables is now in a contrib/sRGBtables sub-directory.
+
+Version 1.5.7beta03 [November 17, 2011]
+ Removed PNG_CONST from the sRGB table declarations in pngpriv.h and png.c
+ Added run-time detection of NEON support.
+ Added contrib/libtests; includes simplified API test and timing test and
+ a color conversion utility for rapid checking of failed 'pngstest' results.
+ Multiple transform bug fixes plus a work-round for double gamma correction.
+ libpng does not support more than one transform that requires linear data
+ at once - if this is tried typically the results is double gamma
+ correction. Since the simplified APIs can need rgb to gray combined with
+ a compose operation it is necessary to do one of these outside the main
+ libpng transform code. This check-in also contains fixes to various bugs
+ in the simplified APIs themselves and to some bugs in compose and rgb to
+ gray (on palette) itself.
+ Fixes for C++ compilation using g++ When libpng source is compiled
+ using g++. The compiler imposes C++ rules on the C source; thus it
+ is desireable to make the source work with either C or C++ rules
+ without throwing away useful error information. This change adds
+ png_voidcast to allow C semantic (void*) cases or the corresponding
+ C++ static_cast operation, as appropriate.
+ Added --noexecstack to assembler file compilation. GCC does not set
+ this on assembler compilation, even though it does on C compilation.
+ This creates security issues if assembler code is enabled; the
+ work-around is to set it by default in the flags for $(CCAS)
+ Work around compilers that don't support declaration of const data. Some
+ compilers fault 'extern const' data declarations (because the data is
+ not initialized); this turns on const-ness only for compilers where
+ this is known to work.
+
+Version 1.5.7beta04 [November 17, 2011]
+ Since the gcc driver does not recognize the --noexecstack flag, we must
+ use the -Wa prefix to have it passed through to the assembler.
+ Also removed a duplicate setting of this flag.
+ Added files that were omitted from the libpng-1.5.7beta03 zip distribution.
+
+Version 1.5.7beta05 [November 25, 2011]
+ Removed "zTXt" from warning in generic chunk decompression function.
+ Validate time settings passed to png_set_tIME() and png_convert_to_rfc1123()
+ (Frank Busse). Note: This prevented CVE-2015-7981 from affecting
+ libpng-1.5.7 and later.
+ Added MINGW support to CMakeLists.txt
+ Reject invalid compression flag or method when reading the iTXt chunk.
+ Backed out 'simplified' API changes. The API seems too complex and there
+ is a lack of consensus or enthusiasm for the proposals. The API also
+ reveals significant bugs inside libpng (double gamma correction and the
+ known bug of being unable to retrieve a corrected palette). It seems
+ better to wait until the bugs, at least, are corrected.
+ Moved pngvalid.c into contrib/libtests
+ Rebuilt Makefile.in, configure, etc., with autoconf-2.68
+
+Version 1.5.7rc01 [December 1, 2011]
+ Replaced an "#if" with "#ifdef" in pngrtran.c
+ Revised #if PNG_DO_BC block in png.c (use #ifdef and add #else)
+
+Version 1.5.7rc02 [December 5, 2011]
+ Revised project files and contrib/pngvalid/pngvalid.c to account for
+ the relocation of pngvalid into contrib/libtests.
+ Revised pngconf.h to use " __declspec(restrict)" only when MSC_VER >= 1400,
+ as in libpng-1.5.4.
+ Put CRLF line endings in the owatcom project files.
+
+Version 1.5.7rc03 [December 7, 2011]
+ Updated CMakeLists.txt to account for the relocation of pngvalid.c
+
+Version 1.5.7 [December 15, 2011]
+ Minor fixes to pngvalid.c for gcc 4.6.2 compatibility to remove warnings
+ reported by earlier versions.
+ Fixed minor memset/sizeof errors in pngvalid.c.
+
+Version 1.6.0beta01 [December 15, 2011]
+ Removed machine-generated configure files from the GIT repository (they will
+ continue to appear in the tarball distributions and in the libpng15 and
+ earlier GIT branches).
+ Restored the new 'simplified' API, which was started in libpng-1.5.7beta02
+ but later deleted from libpng-1.5.7beta05.
+ Added example programs for the new 'simplified' API.
+ Added ANSI-C (C90) headers and require them, and take advantage of the
+ change. Also fixed some of the projects/* and contrib/* files that needed
+ updates for libpng16 and the move of pngvalid.c.
+ With this change the required ANSI-C header files are assumed to exist: the
+ implementation must provide float.h, limits.h, stdarg.h and stddef.h and
+ libpng relies on limits.h and stddef.h existing and behaving as defined
+ (the other two required headers aren't used). Non-ANSI systems that don't
+ have stddef.h or limits.h will have to provide an appropriate fake
+ containing the relevant types and #defines.
+ Dropped support for 16-bit platforms. The use of FAR/far has been eliminated
+ and the definition of png_alloc_size_t is now controlled by a flag so
+ that 'small size_t' systems can select it if necessary. Libpng 1.6 may
+ not currently work on such systems -- it seems likely that it will
+ ask 'malloc' for more than 65535 bytes with any image that has a
+ sufficiently large row size (rather than simply failing to read such
+ images).
+ New tools directory containing tools used to generate libpng code.
+ Fixed race conditions in parallel make builds. With higher degrees of
+ parallelism during 'make' the use of the same temporary file names such
+ as 'dfn*' can result in a race where a temporary file from one arm of the
+ build is deleted or overwritten in another arm. This changes the
+ temporary files for suffix rules to always use $* and ensures that the
+ non-suffix rules use unique file names.
+
+Version 1.6.0beta02 [December 21, 2011]
+ Correct configure builds where build and source directories are separate.
+ The include path of 'config.h' was erroneously made relative in pngvalid.c
+ in libpng 1.5.7.
+
+Version 1.6.0beta03 [December 22, 2011]
+ Start-up code size improvements, error handler flexibility. These changes
+ alter how the tricky allocation of the initial png_struct and png_info
+ structures are handled. png_info is now handled in pretty much the same
+ way as everything else, except that the allocations handle NULL return
+ silently. png_struct is changed in a similar way on allocation and on
+ deallocation a 'safety' error handler is put in place (which should never
+ be required). The error handler itself is changed to permit mismatches
+ in the application and libpng error buffer size; however, this means a
+ silent change to the API to return the jmp_buf if the size doesn't match
+ the size from the libpng compilation; libpng now allocates the memory and
+ this may fail. Overall these changes result in slight code size
+ reductions; however, this is a reduction in code that is always executed
+ so is particularly valuable. Overall on a 64-bit system the libpng DLL
+ decreases in code size by 1733 bytes. pngerror.o increases in size by
+ about 465 bytes because of the new functionality.
+ Added png_convert_to_rfc1123_buffer() and deprecated png_convert_to_rfc1123()
+ to avoid including a spurious buffer in the png_struct.
+
+Version 1.6.0beta04 [December 30, 2011]
+ Regenerated configure scripts with automake-1.11.2
+ Eliminated png_info_destroy(). It is now used only in png.c and only calls
+ one other internal function and memset().
+ Enabled png_get_sCAL_fixed() if floating point APIs are enabled. Previously
+ it was disabled whenever internal fixed point arithmetic was selected,
+ which meant it didn't exist even on systems where FP was available but not
+ preferred.
+ Added pngvalid.c compile time checks for const APIs.
+ Implemented 'restrict' for png_info and png_struct. Because of the way
+ libpng works both png_info and png_struct are always accessed via a
+ single pointer. This means adding C99 'restrict' to the pointer gives
+ the compiler some opportunity to optimize the code. This change allows
+ that.
+ Moved AC_MSG_CHECKING([if libraries can be versioned]) later to the proper
+ location in configure.ac (Gilles Espinasse).
+ Changed png_memcpy to C assignment where appropriate. Changed all those
+ uses of png_memcpy that were doing a simple assignment to assignments
+ (all those cases where the thing being copied is a non-array C L-value).
+ Added some error checking to png_set_*() routines.
+ Removed the reference to the non-exported function png_memcpy() from
+ example.c.
+ Fixed the Visual C 64-bit build - it requires jmp_buf to be aligned, but
+ it had become misaligned.
+ Revised contrib/pngminus/pnm2png.c to avoid warnings when png_uint_32
+ and unsigned long are of different sizes.
+
+Version 1.6.0beta05 [January 15, 2012]
+ Updated manual with description of the simplified API (copied from png.h)
+ Fix bug in pngerror.c: some long warnings were being improperly truncated
+ (CVE-2011-3464, bug introduced in libpng-1.5.3beta05).
+
+Version 1.6.0beta06 [January 24, 2012]
+ Added palette support to the simplified APIs. This commit
+ changes some of the macro definitions in png.h, app code
+ may need corresponding changes.
+ Increased the formatted warning buffer to 192 bytes.
+ Added color-map support to simplified API. This is an initial version for
+ review; the documentation has not yet been updated.
+ Fixed Min/GW uninstall to remove libpng.dll.a
+
+Version 1.6.0beta07 [January 28, 2012]
+ Eliminated Intel icc/icl compiler warnings. The Intel (GCC derived)
+ compiler issues slightly different warnings from those issued by the
+ current vesions of GCC. This eliminates those warnings by
+ adding/removing casts and small code rewrites.
+ Updated configure.ac from autoupdate: added --enable-werror option.
+ Also some layout regularization and removal of introduced tab characters
+ (replaced with 3-character indentation). Obsolete macros identified by
+ autoupdate have been removed; the replacements are all in 2.59 so
+ the pre-req hasn't been changed. --enable-werror checks for support
+ for -Werror (or the given argument) in the compiler. This mimics the
+ gcc configure option by allowing -Werror to be turned on safely; without
+ the option the tests written in configure itself fail compilation because
+ they cause compiler warnings.
+ Rewrote autogen.sh to run autoreconf instead of running tools one-by-one.
+ Conditionalize the install rules for MINGW and CYGWIN in CMakeLists.txt and
+ set CMAKE_LIBRARY_OUTPUT_DIRECTORY to "lib" on all platforms (C. Yapp).
+ Freeze libtool files in the 'scripts' directory. This version of autogen.sh
+ attempts to dissuade people from running it when it is not, or should not,
+ be necessary. In fact, autogen.sh does not work when run in a libpng
+ directory extracted from a tar distribution anymore. You must run it in
+ a GIT clone instead.
+ Added two images to contrib/pngsuite (1-bit and 2-bit transparent grayscale),
+ and renamed three whose names were inconsistent with those in
+ pngsuite/README.txt.
+
+Version 1.6.0beta08 [February 1, 2012]
+ Fixed Image::colormap misalignment in pngstest.c
+ Check libtool/libtoolize version number (2.4.2) in configure.ac
+ Divide test-pngstest.sh into separate pngstest runs for basic and
+ transparent images.
+ Moved automake options to AM_INIT_AUTOMAKE in configure.ac
+ Added color-tests, silent-rules (Not yet implemented in Makefile.am) and
+ version checking to configure.ac
+ Improved pngstest speed by not doing redundant tests and add const to
+ the background parameter of png_image_finish_read. The --background
+ option is now done automagically only when required, so that commandline
+ option no longer exists.
+ Cleaned up pngpriv.h to consistently declare all functions and data.
+ Also eliminated PNG_CONST_DATA, which is apparently not needed but we
+ can't be sure until it is gone.
+ Added symbol prefixing that allows all the libpng external symbols
+ to be prefixed (suggested by Reuben Hawkins).
+ Updated "ftbb*.png" list in the owatcom and vstudio projects.
+ Fixed 'prefix' builds on clean systems. The generation of pngprefix.h
+ should not require itself.
+ Updated INSTALL to explain that autogen.sh must be run in a GIT clone,
+ not in a libpng directory extracted from a tar distribution.
+
+Version 1.6.0beta09 [February 1, 2012]
+ Reverted the prebuilt configure files to libpng-1.6.0beta05 condition.
+
+Version 1.6.0beta10 [February 3, 2012]
+ Added Z_SOLO for zlib-1.2.6+ and correct pngstest tests
+ Updated list of test images in CMakeLists.txt
+ Updated the prebuilt configure files to current condition.
+ Revised INSTALL information about autogen.sh; it works in tar distributions.
+
+Version 1.6.0beta11 [February 16, 2012]
+ Fix character count in pngstest command in projects/owatcom/pngstest.tgt
+ Revised test-pngstest.sh to report PASS/FAIL for each image.
+ Updated documentation about the simplified API.
+ Corrected estimate of error in libpng png_set_rgb_to_gray API. The API is
+ extremely inaccurate for sRGB conversions because it uses an 8-bit
+ intermediate linear value and it does not use the sRGB transform, so it
+ suffers from the known instability in gamma transforms for values close
+ to 0 (see Poynton). The net result is that the calculation has a maximum
+ error of 14.99/255; 0.5/255^(1/2.2). pngstest now uses 15 for the
+ permitted 8-bit error. This may still not be enough because of arithmetic
+ error.
+ Removed some unused arrays (with #ifdef) from png_read_push_finish_row().
+ Fixed a memory overwrite bug in simplified read of RGB PNG with
+ non-linear gamma Also bugs in the error checking in pngread.c and changed
+ quite a lot of the checks in pngstest.c to be correct; either correctly
+ written or not over-optimistic. The pngstest changes are insufficient to
+ allow all possible RGB transforms to be passed; pngstest cmppixel needs
+ to be rewritten to make it clearer which errors it allows and then changed
+ to permit known inaccuracies.
+ Removed tests for no-longer-used *_EMPTY_PLTE_SUPPORTED from pngstruct.h
+ Fixed fixed/float API export conditionals. 1) If FIXED_POINT or
+ FLOATING_POINT options were switched off, png.h ended up with lone ';'
+ characters. This is not valid ANSI-C outside a function. The ';'
+ characters have been moved inside the definition of PNG_FP_EXPORT and
+ PNG_FIXED_EXPORT. 2) If either option was switched off, the declaration
+ of the corresponding functions were completely omitted, even though some
+ of them are still used internally. The result is still valid, but
+ produces warnings from gcc with some warning options (including -Wall). The
+ fix is to cause png.h to declare the functions with PNG_INTERNAL_FUNCTION
+ when png.h is included from pngpriv.h.
+ Check for invalid palette index while reading paletted PNG. When one is
+ found, issue a warning and increase png_ptr->num_palette accordingly.
+ Apps are responsible for checking to see if that happened.
+
+Version 1.6.0beta12 [February 18, 2012]
+ Do not increase num_palette on invalid_index.
+ Relocated check for invalid palette index to pngrtran.c, after unpacking
+ the sub-8-bit pixels.
+ Fixed CVE-2011-3026 buffer overrun bug. This bug was introduced when
+ iCCP chunk support was added at libpng-1.0.6. Deal more correctly with the
+ test on iCCP chunk length. Also removed spurious casts that may hide
+ problems on 16-bit systems.
+
+Version 1.6.0beta13 [February 24, 2012]
+ Eliminated redundant png_push_read_tEXt|zTXt|iTXt|unknown code from
+ pngpread.c and use the sequential png_handle_tEXt, etc., in pngrutil.c;
+ now that png_ptr->buffer is inaccessible to applications, the special
+ handling is no longer useful.
+ Added PNG_SAFE_LIMITS feature to pnglibconf.dfa, pngpriv.h, and new
+ pngusr.dfa to reset the user limits to safe ones if PNG_SAFE_LIMITS is
+ defined. To enable, use "CPPFLAGS=-DPNG_SAFE_LIMITS_SUPPORTED=1" on the
+ configure command or put #define PNG_SAFE_LIMITS_SUPPORTED in
+ pnglibconf.h.prebuilt and pnglibconf.h.
+
+Version 1.6.0beta14 [February 27, 2012]
+ Added information about the new limits in the manual.
+ Updated Makefile.in
+
+Version 1.6.0beta15 [March 2, 2012]
+ Removed unused "current_text" members of png_struct and the png_free()
+ of png_ptr->current_text from pngread.c
+ Rewrote pngstest.c for substantial speed improvement.
+ Fixed transparent pixel and 16-bit rgb tests in pngstest and removed a
+ spurious check in pngwrite.c
+ Added PNG_IMAGE_FLAG_FAST for the benefit of applications that store
+ intermediate files, or intermediate in-memory data, while processing
+ image data with the simplified API. The option makes the files larger
+ but faster to write and read. pngstest now uses this by default; this
+ can be disabled with the --slow option.
+ Improved pngstest fine tuning of error numbers, new test file generator.
+ The generator generates images that test the full range of sample values,
+ allow the error numbers in pngstest to be tuned and checked. makepng
+ also allows generation of images with extra chunks, although this is
+ still work-in-progress.
+ Added check for invalid palette index while reading.
+ Fixed some bugs in ICC profile writing. The code should now accept
+ all potentially valid ICC profiles and reject obviously invalid ones.
+ It now uses png_error() to do so rather than casually writing a PNG
+ without the necessary color data.
+ Removed whitespace from the end of lines in all source files and scripts.
+
+Version 1.6.0beta16 [March 6, 2012]
+ Relocated palette-index checking function from pngrutil.c to pngtrans.c
+ Added palette-index checking while writing.
+ Changed png_inflate() and calling routines to avoid overflow problems.
+ This is an intermediate check-in that solves the immediate problems and
+ introduces one performance improvement (avoiding a copy via png_ptr->zbuf.)
+ Further changes will be made to make ICC profile handling more secure.
+ Fixed build warnings (MSVC, GCC, GCC v3). Cygwin GCC with default options
+ declares 'index' as a global, causing a warning if it is used as a local
+ variable. GCC 64-bit warns about assigning a (size_t) (unsigned 64-bit)
+ to an (int) (signed 32-bit). MSVC, however, warns about using the
+ unary '-' operator on an unsigned value (even though it is well defined
+ by ANSI-C to be ~x+1). The padding calculation was changed to use a
+ different method. Removed the tests on png_ptr->pass.
+ Added contrib/libtests/tarith.c to test internal arithmetic functions from
+ png.c. This is a libpng maintainer program used to validate changes to the
+ internal arithmetic functions.
+ Made read 'inflate' handling like write 'deflate' handling. The read
+ code now claims and releases png_ptr->zstream, like the write code.
+ The bug whereby the progressive reader failed to release the zstream
+ is now fixed, all initialization is delayed, and the code checks for
+ changed parameters on deflate rather than always calling
+ deflatedEnd/deflateInit.
+ Validate the zTXt strings in pngvalid.
+ Added code to validate the windowBits value passed to deflateInit2().
+ If the call to deflateInit2() is wrong a png_warning will be issued
+ (in fact this is harmless, but the PNG data produced may be sub-optimal).
+
+Version 1.6.0beta17 [March 10, 2012]
+ Fixed PNG_LIBPNG_BUILD_BASE_TYPE definition.
+ Reject all iCCP chunks after the first, even if the first one is invalid.
+ Deflate/inflate was reworked to move common zlib calls into single
+ functions [rw]util.c. A new shared keyword check routine was also added
+ and the 'zbuf' is no longer allocated on progressive read. It is now
+ possible to call png_inflate() incrementally. A warning is no longer
+ issued if the language tag or translated keyword in the iTXt chunk
+ has zero length.
+ If benign errors are disabled use maximum window on ancilliary inflate.
+ This works round a bug introduced in 1.5.4 where compressed ancillary
+ chunks could end up with a too-small windowBits value in the deflate
+ header.
+
+Version 1.6.0beta18 [March 16, 2012]
+ Issue a png_benign_error() instead of png_warning() about bad palette index.
+ In pngtest, treat benign errors as errors if "-strict" is present.
+ Fixed an off-by-one error in the palette index checking function.
+ Fixed a compiler warning under Cygwin (Windows-7, 32-bit system)
+ Revised example.c to put text strings in a temporary character array
+ instead of directly assigning string constants to png_textp members.
+ This avoids compiler warnings when -Wwrite-strings is enabled.
+ Added output flushing to aid debugging under Visual Studio. Unfortunately
+ this is necessary because the VS2010 output window otherwise simply loses
+ the error messages on error (they weren't flushed to the window before
+ the process exited, apparently!)
+ Added configuration support for benign errors and changed the read
+ default. Also changed some warnings in the iCCP and sRGB handling
+ from to benign errors. Configuration now makes read benign
+ errors warnings and write benign errors to errors by default (thus
+ changing the behavior on read). The simplified API always forces
+ read benign errors to warnings (regardless of the system default, unless
+ this is disabled in which case the simplified API can't be built.)
+
+Version 1.6.0beta19 [March 18, 2012]
+ Work around for duplicate row start calls; added warning messages.
+ This turns on PNG_FLAG_DETECT_UNINITIALIZED to detect app code that
+ fails to call one of the 'start' routines (not enabled in libpng-1.5
+ because it is technically an API change, since it did normally work
+ before.) It also makes duplicate calls to png_read_start_row (an
+ internal function called at the start of the image read) benign, as
+ they were before changes to use png_inflate_claim. Somehow webkit is
+ causing this to happen; this is probably a mis-feature in the zlib
+ changes so this commit is only a work-round.
+ Removed erroneous setting of DETECT_UNINITIALIZED and added more
+ checks. The code now does a png_error if an attempt is made to do the
+ row initialization twice; this is an application error and it has
+ serious consequences because the transform data in png_struct is
+ changed by each call.
+ Added application error reporting and added chunk names to read
+ benign errors; also added --strict to pngstest - not enabled
+ yet because a warning is produced.
+ Avoid the double gamma correction warning in the simplified API.
+ This allows the --strict option to pass in the pngstest checks
+
+Version 1.6.0beta20 [March 29, 2012]
+ Changed chunk handler warnings into benign errors, incrementally load iCCP
+ Added checksum-icc.c to contrib/tools
+ Prevent PNG_EXPAND+PNG_SHIFT doing the shift twice.
+ Recognize known sRGB ICC profiles while reading; prefer writing the
+ iCCP profile over writing the sRGB chunk, controlled by the
+ PNG_sRGB_PROFILE_CHECKS option.
+ Revised png_set_text_2() to avoid potential memory corruption (fixes
+ CVE-2011-3048, also known as CVE-2012-3425).
+
+Version 1.6.0beta21 [April 27, 2012]
+ Revised scripts/makefile.darwin: use system zlib; remove quotes around
+ architecture list; add missing ppc architecture; add architecture options
+ to shared library link; don't try to create a shared lib based on missing
+ RELEASE variable.
+ Enable png_set_check_for_invalid_index() for both read and write.
+ Removed #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED in pngpriv.h around
+ declaration of png_handle_unknown().
+ Added -lssp_nonshared in a comment in scripts/makefile.freebsd
+ and changed deprecated NOOBJ and NOPROFILE to NO_OBJ and NO_PROFILE.
+
+Version 1.6.0beta22 [May 23, 2012]
+ Removed need for -Wno-cast-align with clang. clang correctly warns on
+ alignment increasing pointer casts when -Wcast-align is passed. This
+ fixes the cases that clang warns about either by eliminating the
+ casts from png_bytep to png_uint_16p (pngread.c), or, for pngrutil.c
+ where the cast is previously verified or pngstest.c where it is OK, by
+ introducing new png_aligncast macros to do the cast in a way that clang
+ accepts.
+
+Version 1.6.0beta23 [June 6, 2012]
+ Revised CMakeLists.txt to not attempt to make a symlink under mingw.
+ Made fixes for new optimization warnings from gcc 4.7.0. The compiler
+ performs an optimization which is safe; however it then warns about it.
+ Changing the type of 'palette_number' in pngvalid.c removes the warning.
+ Do not depend upon a GCC feature macro being available for use in generating
+ the linker mapfile symbol prefix.
+ Improved performance of new do_check_palette_indexes() function (only
+ update the value when it actually increases, move test for whether
+ the check is wanted out of the function.
+
+Version 1.6.0beta24 [June 7, 2012]
+ Don't check palette indexes if num_palette is 0 (as it can be in MNG files).
+
+Version 1.6.0beta25 [June 16, 2012]
+ Revised png_set_keep_unknown_chunks() so num_chunks < 0 means ignore all
+ unknown chunks and all known chunks except for IHDR, PLTE, tRNS, IDAT,
+ and IEND. Previously it only meant ignore all unknown chunks, the
+ same as num_chunks == 0. Revised png_image_skip_unused_chunks() to
+ provide a list of chunks to be processed instead of a list of chunks to
+ ignore. Revised contrib/gregbook/readpng2.c accordingly.
+
+Version 1.6.0beta26 [July 10, 2012]
+ Removed scripts/makefile.cegcc from the *.zip and *.7z distributions; it
+ depends on configure, which is not included in those archives.
+ Moved scripts/chkfmt to contrib/tools.
+ Changed "a+w" to "u+w" in Makefile.in to fix CVE-2012-3386.
+
+Version 1.6.0beta27 [August 11, 2012]
+ Do not compile PNG_DEPRECATED, PNG_ALLOC and PNG_PRIVATE when __GNUC__ < 3.
+ Do not use __restrict when GNUC is <= 3.1
+ Removed references to png_zalloc() and png_zfree() from the manual.
+ Fixed configurations where floating point is completely disabled. Because
+ of the changes to support symbol prefixing PNG_INTERNAL_FUNCTION declares
+ floating point APIs during libpng builds even if they are completely
+ disabled. This requires the png floating point types (png_double*) to be
+ declared even though the functions are never actually defined. This
+ change provides a dummy definition so that the declarations work, yet any
+ implementation will fail to compile because of an incomplete type.
+ Re-eliminated the use of strcpy() in pngtest.c. An unncessary use of
+ strcpy() was accidentally re-introduced in libpng16; this change replaces
+ it with strncpy().
+ Eliminated use of png_sizeof(); use sizeof() instead.
+ Use a consistent style for (sizeof type) and (sizeof (array))
+ Cleanup of png_set_filler(). This function does very different things on
+ read and write. In libpng 1.6 the two cases can be distinguished and
+ considerable code cleanup, and extra error checking, is possible. This
+ makes calls on the write side that have no effect be ignored with a
+ png_app_error(), which can be disabled in the app using
+ png_set_benign_errors(), and removes the spurious use of usr_channels
+ on the read side.
+ Insist on autotools 1.12.1 for git builds because there are security issues
+ with 1.12 and insisting on anything less would allow 1.12 to be used.
+ Removed info_ptr->signature[8] from WRITE-only builds.
+ Add some conditions for compiling png_fixed(). This is a small function
+ but it requires "-lm" on some platforms.
+ Cause pngtest --strict to fail on any warning from libpng (not just errors)
+ and cause it not to fail at the comparison step if libpng lacks support
+ for writing chunks that it reads from the input (currently only implemented
+ for compressed text chunks).
+ Make all three "make check" test programs work without READ or WRITE support.
+ Now "make check" will succeed even if libpng is compiled with -DPNG_NO_READ
+ or -DPNG_NO_WRITE. The tests performed are reduced, but the basic reading
+ and writing of a PNG file is always tested by one or more of the tests.
+ Consistently use strlen(), memset(), memcpy(), and memcmp() instead of the
+ png_strlen(), png_memset(), png_memcpy(), and png_memcmp() macros.
+ Removed the png_sizeof(), png_strlen(), png_memset(), png_memcpy(), and
+ png_memcmp() macros.
+ Work around gcc 3.x and Microsoft Visual Studio 2010 complaints. Both object
+ to the split initialization of num_chunks.
+
+Version 1.6.0beta28 [August 29, 2012]
+ Unknown handling fixes and clean up. This adds more correct option
+ control of the unknown handling, corrects the pre-existing bug where
+ the per-chunk 'keep' setting is ignored and makes it possible to skip
+ IDAT chunks in the sequential reader (broken in earlier 1.6 versions).
+ There is a new test program, test-unknown.c, which is a work in progress
+ (not currently part of the test suite). Comments in the header files now
+ explain how the unknown handling works.
+ Allow fine grain control of unknown chunk APIs. This change allows
+ png_set_keep_unknown_chunks() to be turned off if not required and causes
+ both read and write to behave appropriately (on read this is only possible
+ if the user callback is used to handle unknown chunks). The change
+ also removes the support for storing unknown chunks in the info_struct
+ if the only unknown handling enabled is via the callback, allowing libpng
+ to be configured with callback reading and none of the unnecessary code.
+ Corrected fix for unknown handling in pngtest. This reinstates the
+ libpng handling of unknown chunks other than vpAg and sTER (including
+ unsafe-to-copy chunks which were dropped before) and eliminates the
+ repositioning of vpAg and sTER in pngtest.png by changing pngtest.png
+ (so the chunks are where libpng would put them).
+ Added "tunknown" test and corrected a logic error in png_handle_unknown()
+ when SAVE support is absent. Moved the shell test scripts for
+ contrib/libtests from the libpng top directory to contrib/libtests.
+ png_handle_unknown() must always read or skip the chunk, if
+ SAVE_UNKNOWN_CHUNKS is turned off *and* the application does not set
+ a user callback an unknown chunk will not be read, leading to a read
+ error, which was revealed by the "tunknown" test.
+ Cleaned up and corrected ICC profile handling.
+ contrib/libtests/makepng: corrected 'rgb' and 'gray' cases. profile_error
+ messages could be truncated; made a correct buffer size calculation and
+ adjusted pngerror.c appropriately. png_icc_check_* checking improved;
+ changed the functions to receive the correct color type of the PNG on read
+ or write and check that it matches the color space of the profile (despite
+ what the comments said before, there is danger in assuming the app will
+ cope correctly with an RGB profile on a grayscale image and, since it
+ violates the PNG spec, allowing it is certain to produce inconsistent
+ app behavior and might even cause app crashes.) Check that profiles
+ contain the tags needed to process the PNG (tags all required by the ICC
+ spec). Removed unused PNG_STATIC from pngpriv.h.
+
+Version 1.6.0beta29 [September 4, 2012]
+ Fixed the simplified API example programs to add the *colormap parameter
+ to several of he API and improved the error message if the version field
+ is not set.
+ Added contrib/examples/* to the *.zip and *.7z distributions.
+ Updated simplified API synopses and description of the png_image structure
+ in the manual.
+ Made makepng and pngtest produce identical PNGs, add "--relaxed" option
+ to pngtest. The "--relaxed" option turns off the benign errors that are
+ enabled by default in pre-RC builds. makepng can now write ICC profiles
+ where the length has not been extended to a multiple of 4, and pngtest
+ now intercepts all libpng errors, allowing the previously-introduced
+ "--strict test" on no warnings to actually work.
+ Improved ICC profile handling including cHRM chunk generation and fixed
+ Cygwin+MSVC build errors. The ICC profile handling now includes more
+ checking. Several errors that caused rejection of the profile are now
+ handled with a warning in such a way that the invalid profiles will be
+ read by default in release (but not pre-RC) builds but will not be
+ written by default. The easy part of handling the cHRM chunk is written,
+ where the ICC profile contains the required data. The more difficult
+ part plus guessing a gAMA value requires code to pass selected RGB values
+ through the profile.
+
+Version 1.6.0beta30 [October 24, 2012]
+ Changed ICC profile matrix/vector types to not depend on array type rules.
+ By the ANSI-C standard the new types should be identical to the previous
+ versions, and all known versions of gcc tested with the previous versions
+ except for GCC-4.2.1 work with this version. The change makes the ANSI-C
+ rule that const applied to an array of elements applies instead to the
+ elements in the array moot by explicitly applying const to the base
+ elements of the png_icc_matrix and png_icc_vector types. The accidental
+ (harmless) 'const' previously applied to the parameters of two of the
+ functions have also been removed.
+ Added a work around for GCC 4.2 optimization bug.
+ Marked the broken (bad white point) original HP sRGB profiles correctly and
+ correct comments.
+ Added -DZ_SOLO to contrib/pngminim/*/makefile to work with zlib-1.2.7
+ Use /MDd for vstudio debug builds. Also added pngunkown to the vstudio
+ builds, fixed build errors and corrected a minor exit code error in
+ pngvalid if the 'touch' file name is invalid.
+ Add updated WARNING file to projects/vstudio from libpng 1.5/vstudio
+ Fixed build when using #define PNG_NO_READ_GAMMA in png_do_compose() in
+ pngrtran.c (Domani Hannes).
+
+Version 1.6.0beta31 [November 1, 2012]
+ Undid the erroneous change to vstudio/pngvalid build in libpng-1.6.0beta30.
+ Made pngvalid so that it will build outside the libpng source tree.
+ Made builds -DPNG_NO_READ_GAMMA compile (the unit tests still fail).
+ Made PNG_NO_READ_GAMMA switch off interfaces that depend on READ_GAMMA.
+ Prior to 1.6.0 switching off READ_GAMMA did unpredictable things to the
+ interfaces that use it (specifically, png_do_background in 1.4 would
+ simply display composite for grayscale images but do composition
+ with the incorrect arithmetic for color ones). In 1.6 the semantic
+ of -DPNG_NO_READ_GAMMA is changed to simply disable any interface that
+ depends on it; this obliges people who set it to consider whether they
+ really want it off if they happen to use any of the interfaces in
+ question (typically most users who disable it won't).
+ Fixed GUIDs in projects/vstudio. Some were duplicated or missing,
+ resulting in VS2010 having to update the files.
+ Removed non-working ICC profile support code that was mostly added to
+ libpng-1.6.0beta29 and beta30. There was too much code for too little
+ gain; implementing full ICC color correction may be desireable but is left
+ up to applications.
+
+Version 1.6.0beta32 [November 25, 2012]
+ Fixed an intermittent SEGV in pngstest due to an uninitialized array element.
+ Added the ability for contrib/libtests/makepng.c to make a PNG with just one
+ color. This is useful for debugging pngstest color inaccuracy reports.
+ Fixed error checking in the simplified write API (Olaf van der Spek)
+ Made png_user_version_check() ok to use with libpng version 1.10.x and later.
+
+Version 1.6.0beta33 [December 15, 2012]
+ Fixed typo in png.c (PNG_SET_CHUNK_MALLOC_MAX should be PNG_CHUNK_MALLOC_MAX)
+ that causes the MALLOC_MAX limit not to work (John Bowler)
+ Change png_warning() to png_app_error() in pngwrite.c and comment the
+ fall-through condition.
+ Change png_warning() to png_app_warning() in png_write_tRNS().
+ Rearranged the ARM-NEON optimizations: Isolated the machine specific code
+ to the hardware subdirectory and added comments to pngrutil.c so that
+ implementors of other optimizations know what to do.
+ Fixed cases of unquoted DESTDIR in Makefile.am
+ Rebuilt Makefile.in, etc., with autoconf-2.69 and automake-1.12.5.
+
+Version 1.6.0beta34 [December 19, 2012]
+ Cleaned up whitespace in the synopsis portion of the manpage "libpng.3"
+ Disassembled the version number in scripts/options.awk (necessary for
+ building on SunOs).
+
+Version 1.6.0beta35 [December 23, 2012]
+ Made default Zlib compression settings be configurable. This adds #defines to
+ pnglibconf.h to control the defaults.
+ Fixed Windows build issues, enabled ARM compilation. Various warnings issued
+ by earlier versions of GCC fixed for Cygwin and Min/GW (which both use old
+ GCCs.) ARM support is enabled by default in zlib.props (unsupported by
+ Microsoft) and ARM compilation is made possible by deleting the check for
+ x86. The test programs cannot be run because they are not signed.
+
+Version 1.6.0beta36 [January 2, 2013]
+ Discontinued distributing libpng-1.x.x.tar.bz2.
+ Discontinued distributing libpng-1.7.0-1.6.0-diff.txt and similar.
+ Rebuilt configure with autoconf-2.69 (inadvertently not done in beta33)
+ Fixed 'make distcheck' on SUN OS - libpng.so was not being removed
+
+Version 1.6.0beta37 [January 10, 2013]
+ Fixed conceivable but difficult to repro overflow. Also added two test
+ programs to generate and test a PNG which should have the problem.
+
+Version 1.6.0beta39 [January 19, 2013]
+ Again corrected attempt at overflow detection in png_set_unknown_chunks()
+ (CVE-2013-7353). Added overflow detection in png_set_sPLT() and
+ png_set_text_2() (CVE-2013-7354).
+
+Version 1.6.0beta40 [January 20, 2013]
+ Use consistent handling of overflows in text, sPLT and unknown png_set_* APIs
+
+Version 1.6.0rc01 [January 26, 2013]
+ No changes.
+
+Version 1.6.0rc02 [February 4, 2013]
+ Added png_get_palette_max() function.
+
+Version 1.6.0rc03 [February 5, 2013]
+ Fixed the png_get_palette_max API.
+
+Version 1.6.0rc04 [February 7, 2013]
+ Turn serial tests back on (recently turned off by autotools upgrade).
+
+Version 1.6.0rc05 [February 8, 2013]
+ Update manual about png_get_palette_max().
+
+Version 1.6.0rc06 [February 9, 2013]
+ Fixed missing dependency in --prefix builds The intermediate
+ internal 'prefix.h' file can only be generated correctly after
+ pnglibconf.h, however the dependency was not in Makefile.am. The
+ symptoms are unpredictable depending on the order make chooses to
+ build pngprefix.h and pnglibconf.h, often the error goes unnoticed
+ because there is a system pnglibconf.h to use instead.
+
+Version 1.6.0rc07 [February 10, 2013]
+ Enclosed the new png_get_palette_max in #ifdef PNG_GET_PALETTE_MAX_SUPPORTED
+ block, and revised pnglibconf.h and pnglibconf.h.prebuilt accordingly.
+
+Version 1.6.0rc08 [February 10, 2013]
+ Fix typo in png.h #ifdef
+
+Version 1.6.0 [February 14, 2013]
+ No changes.
+
+Version 1.6.1beta01 [February 16, 2013]
+ Made symbol prefixing work with the ARM neon optimizations. Also allow
+ pngpriv.h to be included for preprocessor definitions only, so it can
+ be used in non-C/C++ files. Back ported from libpng 1.7.
+ Made sRGB check numbers consistent.
+ Ported libpng 1.5 options.awk/dfn file handling to 1.6, fixed one bug.
+ Removed cc -E workround, corrected png_get_palette_max API Tested on
+ SUN OS cc 5.9, which demonstrates the tokenization problem previously
+ avoided by using /lib/cpp. Since all .dfn output is now protected in
+ double quotes unless it is to be macro substituted the fix should
+ work everywhere.
+ Enabled parallel tests - back ported from libpng-1.7.
+ scripts/pnglibconf.dfa formatting improvements back ported from libpng17.
+ Fixed a race condition in the creation of the build 'scripts' directory
+ while building with a parallel make.
+ Use approved/supported Android method to check for NEON, use Linux/POSIX
+ 1003.1 API to check /proc/self/auxv avoiding buffer allocation and other
+ library calls (ported from libpng15).
+
+Version 1.6.1beta02 [February 19, 2013]
+ Use parentheses more consistently in "#if defined(MACRO)" tests.
+ Folded long lines.
+ Reenabled code to allow zero length PLTE chunks for MNG.
+
+Version 1.6.1beta03 [February 22, 2013]
+ Fixed ALIGNED_MEMORY support.
+ Added a new configure option:
+ --enable-arm-neon=always will stop the run-time checks. New checks
+ within arm/arm_init.c will cause the code not to be compiled unless
+ __ARM_NEON__ is set. This should make it fail safe (if someone asks
+ for it on then the build will fail if it can't be done.)
+ Updated the INSTALL document.
+
+Version 1.6.1beta04 [February 27, 2013]
+ Revised INSTALL to recommend using CPPFLAGS instead of INCLUDES.
+ Revised scripts/makefile.freebsd to respect ZLIBLIB and ZLIBINC.
+ Revised scripts/dfn.awk to work with the buggy MSYS awk that has trouble
+ with CRLF line endings.
+
+Version 1.6.1beta05 [March 1, 2013]
+ Avoid a possible memory leak in contrib/gregbook/readpng.c
+
+Version 1.6.1beta06 [March 4, 2013]
+ Better documentation of unknown handling API interactions.
+ Corrected Android builds and corrected libpng.vers with symbol
+ prefixing. It also makes those tests compile and link on Android.
+ Added an API png_set_option() to set optimization options externally,
+ providing an alternative and general solution for the non-portable
+ run-time tests used by the ARM Neon code, using the PNG_ARM_NEON option.
+ The order of settings vs options in pnglibconf.h is reversed to allow
+ settings to depend on options and options can now set (or override) the
+ defaults for settings.
+
+Version 1.6.1beta07 [March 7, 2013]
+ Corrected simplified API default gamma for color-mapped output, added
+ a flag to change default. In 1.6.0 when the simplified API was used
+ to produce color-mapped output from an input image with no gamma
+ information the gamma assumed for the input could be different from
+ that assumed for non-color-mapped output. In particular 16-bit depth
+ input files were assumed to be sRGB encoded, whereas in the 'direct'
+ case they were assumed to have linear data. This was an error. The
+ fix makes the simplified API treat all input files the same way and
+ adds a new flag to the png_image::flags member to allow the
+ application/user to specify that 16-bit files contain sRGB data
+ rather than the default linear.
+ Fixed bugs in the pngpixel and makepng test programs.
+
+Version 1.6.1beta08 [March 7, 2013]
+ Fixed CMakelists.txt to allow building a single variant of the library
+ (Claudio Bley):
+ Introduced a PNG_LIB_TARGETS variable that lists all activated library
+ targets. It is an error if this variable ends up empty, ie. you have
+ to build at least one library variant.
+ Made the *_COPY targets only depend on library targets actually being build.
+ Use PNG_LIB_TARGETS to unify a code path.
+ Changed the CREATE_SYMLINK macro to expect the full path to a file as the
+ first argument. When symlinking the filename component of that path is
+ determined and used as the link target.
+ Use copy_if_different in the CREATE_SYMLINK macro.
+
+Version 1.6.1beta09 [March 13, 2013]
+ Eliminated two warnings from the Intel C compiler. The warnings are
+ technically valid, although a reasonable treatment of division would
+ show it to be incorrect.
+
+Version 1.6.1rc01 [March 21, 2013]
+ No changes.
+
+Version 1.6.1 [March 28, 2013]
+ No changes.
+
+Version 1.6.2beta01 [April 14, 2013]
+ Updated documentation of 1.5.x to 1.6.x changes in iCCP chunk handling.
+ Fixed incorrect warning of excess deflate data. End condition - the
+ warning would be produced if the end of the deflate stream wasn't read
+ in the last row. The warning is harmless.
+ Corrected the test on user transform changes on read. It was in the
+ png_set of the transform function, but that doesn't matter unless the
+ transform function changes the rowbuf size, and that is only valid if
+ transform_info is called.
+ Corrected a misplaced closing bracket in contrib/libtests/pngvalid.c
+ (Flavio Medeiros).
+ Corrected length written to uncompressed iTXt chunks (Samuli Suominen).
+ Bug was introduced in libpng-1.6.0.
+
+Version 1.6.2rc01 [April 18, 2013]
+ Added contrib/tools/fixitxt.c, to repair the erroneous iTXt chunk length
+ written by libpng-1.6.0 and 1.6.1.
+ Disallow storing sRGB information when the sRGB is not supported.
+
+Version 1.6.2rc02 [April 18, 2013]
+ Merge pngtest.c with libpng-1.7.0
+
+Version 1.6.2rc03 [April 22, 2013]
+ Trivial spelling cleanup.
+
+Version 1.6.2rc04 and 1.6.2rc05 [omitted]
+
+Version 1.6.2rc06 [April 24, 2013]
+ Reverted to version 1.6.2rc03. Recent changes to arm/neon support
+ have been ported to libpng-1.7.0beta09 and will reappear in version
+ 1.6.3beta01.
+
+Version 1.6.2 [April 25, 2013]
+ No changes.
+
+Version 1.6.3beta01 [April 25, 2013]
+ Revised stack marking in arm/filter_neon.S and configure.ac.
+ Ensure that NEON filter stuff is completely disabled when switched 'off'.
+ Previously the ARM NEON specific files were still built if the option
+ was switched 'off' as opposed to being explicitly disabled.
+
+Version 1.6.3beta02 [April 26, 2013]
+ Test for 'arm*' not just 'arm' in the host_cpu configure variable.
+ Rebuilt the configure scripts.
+
+Version 1.6.3beta03 [April 30, 2013]
+ Expanded manual paragraph about writing private chunks, particularly
+ the need to call png_set_keep_unknown_chunks() when writing them.
+ Avoid dereferencing NULL pointer possibly returned from
+ png_create_write_struct() (Andrew Church).
+
+Version 1.6.3beta05 [May 9, 2013]
+ Calculate our own zlib windowBits when decoding rather than trusting the
+ CMF bytes in the PNG datastream.
+ Added an option to force maximum window size for inflating, which was
+ the behavior of libpng15 and earlier, via a new PNG_MAXIMUM_INFLATE_WINDOW
+ option for png_set_options().
+ Added png-fix-itxt and png-fix-too-far-back to the built programs and
+ removed warnings from the source code and timepng that are revealed as
+ a result.
+ Detect wrong libpng versions linked to png-fix-too-far-back, which currently
+ only works with libpng versions that can be made to reliably fail when
+ the deflate data contains an out-of-window reference. This means only
+ 1.6 and later.
+ Fixed gnu issues: g++ needs a static_cast, gcc 4.4.7 has a broken warning
+ message which it is easier to work round than ignore.
+ Updated contrib/pngminus/pnm2png.c (Paul Stewart):
+ Check for EOF
+ Ignore "#" delimited comments in input file to pnm2png.c.
+ Fixed whitespace handling
+ Added a call to png_set_packing()
+ Initialize dimension values so if sscanf fails at least we have known
+ invalid values.
+ Attempt to detect configuration issues with png-fix-too-far-back, which
+ requires both the correct libpng and the correct zlib to function
+ correctly.
+ Check ZLIB_VERNUM for mismatches, enclose #error in quotes
+ Added information in the documentation about problems with and fixes for
+ the bad CRC and bad iTXt chunk situations.
+
+Version 1.6.3beta06 [May 12, 2013]
+ Allow contrib/pngminus/pnm2png.c to compile without WRITE_INVERT and
+ WRITE_PACK supported (writes error message that it can't read P1 or
+ P4 PBM files).
+ Improved png-fix-too-far-back usage message, added --suffix option.
+ Revised contrib/pngminim/*/makefile to generate pnglibconf.h with the
+ right zlib header files.
+ Separated CPPFLAGS and CFLAGS in contrib/pngminim/*/makefile
+
+Version 1.6.3beta07 [June 8, 2013]
+ Removed a redundant test in png_set_IHDR().
+ Added set(CMAKE_CONFIGURATION_TYPES ...) to CMakeLists.txt (Andrew Hundt)
+ Deleted set(CMAKE_BUILD_TYPE) block from CMakeLists.txt
+ Enclose the prototypes for the simplified write API in
+ #ifdef PNG_STDIO_SUPPORTED/#endif
+ Make ARM NEON support work at compile time (not just configure time).
+ This moves the test on __ARM_NEON__ into pngconf.h to avoid issues when
+ using a compiler that compiles for multiple architectures at one time.
+ Removed PNG_FILTER_OPTIMIZATIONS and PNG_ARM_NEON_SUPPORTED from
+ pnglibconf.h, allowing more of the decisions to be made internally
+ (pngpriv.h) during the compile. Without this, symbol prefixing is broken
+ under certain circumstances on ARM platforms. Now only the API parts of
+ the optimizations ('check' vs 'api') are exposed in the public header files
+ except that the new setting PNG_ARM_NEON_OPT documents how libpng makes the
+ decision about whether or not to use the optimizations.
+ Protect symbol prefixing against CC/CPPFLAGS/CFLAGS useage.
+ Previous iOS/Xcode fixes for the ARM NEON optimizations moved the test
+ on __ARM_NEON__ from configure time to compile time. This breaks symbol
+ prefixing because the definition of the special png_init_filter_functions
+ call was hidden at configure time if the relevant compiler arguments are
+ passed in CFLAGS as opposed to CC. This change attempts to avoid all
+ the confusion that would result by declaring the init function even when
+ it is not used, so that it will always get prefixed.
+
+Version 1.6.3beta08 [June 18, 2013]
+ Revised libpng.3 so that "doclifter" can process it.
+
+Version 1.6.3beta09 [June 27, 2013]
+ Revised example.c to illustrate use of PNG_DEFAULT_sRGB and PNG_GAMMA_MAC_18
+ as parameters for png_set_gamma(). These have been available since
+ libpng-1.5.4.
+ Renamed contrib/tools/png-fix-too-far-back.c to pngfix.c and revised it
+ to check all compressed chunks known to libpng.
+
+Version 1.6.3beta10 [July 5, 2013]
+ Updated documentation to show default behavior of benign errors correctly.
+ Only compile ARM code when PNG_READ_SUPPORTED is defined.
+ Fixed undefined behavior in contrib/tools/pngfix.c and added new strip
+ option. pngfix relied on undefined behavior and even a simple change from
+ gcc to g++ caused it to fail. The new strip option 'unsafe' has been
+ implemented and is the default if --max is given. Option names have
+ been clarified, with --strip=transform now stripping the bKGD chunk,
+ which was stripped previously with --strip=unused.
+ Added all documented chunk types to pngpriv.h
+ Unified pngfix.c source with libpng17.
+
+Version 1.6.3rc01 [July 11, 2013]
+ No changes.
+
+Version 1.6.3 [July 18, 2013]
+ Revised manual about changes in iTXt chunk handling made in libpng-1.6.0.
+ Added "/* SAFE */" comments in pngrutil.c and pngrtran.c where warnings
+ may be erroneously issued by code-checking applications.
+
+Version 1.6.4beta01 [August 21, 2013]
+ Added information about png_set_options() to the manual.
+ Delay calling png_init_filter_functions() until a row with nonzero filter
+ is found.
+
+Version 1.6.4beta02 [August 30, 2013]
+ Fixed inconsistent conditional compilation of png_chunk_unknown_handling()
+ prototype, definition, and usage. Made it depend on
+ PNG_HANDLE_AS_UNKNOWN_SUPPORTED everywhere.
+
+Version 1.6.4rc01 [September 5, 2013]
+ No changes.
+
+Version 1.6.4 [September 12, 2013]
+ No changes.
+
+Version 1.6.5 [September 14, 2013]
+ Removed two stray lines of code from arm/arm_init.c.
+
+Version 1.6.6 [September 16, 2013]
+ Removed two stray lines of code from arm/arm_init.c, again.
+
+Version 1.6.7beta01 [September 30, 2013]
+ Revised unknown chunk code to correct several bugs in the NO_SAVE_/NO_WRITE
+ combination
+ Allow HANDLE_AS_UNKNOWN to work when other options are configured off. Also
+ fixed the pngminim makefiles to work when $(MAKEFLAGS) contains stuff
+ which terminates the make options (as by default in recent versions of
+ Gentoo).
+ Avoid up-cast warnings in pngvalid.c. On ARM the alignment requirements of
+ png_modifier are greater than that of png_store and as a consequence
+ compilation of pngvalid.c results in a warning about increased alignment
+ requirements because of the bare cast to (png_modifier*). The code is safe,
+ because the pointer is known to point to a stack allocated png_modifier,
+ but this change avoids the warning.
+ Fixed default behavior of ARM_NEON_API. If the ARM NEON API option was
+ compiled without the CHECK option it defaulted to on, not off.
+ Check user callback behavior in pngunknown.c. Previous versions compiled
+ if SAVE_UNKNOWN was not available but did nothing since the callback
+ was never implemented.
+ Merged pngunknown.c with 1.7 version and back ported 1.7 improvements/fixes
+
+Version 1.6.7beta02 [October 12, 2013]
+ Made changes for compatibility with automake 1.14:
+ 1) Added the 'compile' program to the list of programs that must be cleaned
+ in autogen.sh
+ 2) Added 'subdir-objects' which causes .c files in sub-directories to be
+ compiled such that the corresponding .o files are also in the
+ sub-directory. This is because automake 1.14 warns that the
+ current behavior of compiling to the top level directory may be removed
+ in the future.
+ 3) Updated dependencies on pnglibconf.h to match the new .o locations and
+ added all the files in contrib/libtests and contrib/tools that depend
+ on pnglibconf.h
+ 4) Added 'BUILD_SOURCES = pnglibconf.h'; this is the automake recommended
+ way of handling the dependencies of sources that are machine generated;
+ unfortunately it only works if the user does 'make all' or 'make check',
+ so the dependencies (3) are still required.
+ Cleaned up (char*) casts of zlib messages. The latest version of the Intel C
+ compiler complains about casting a string literal as (char*), so copied the
+ treatment of z_const from the library code into pngfix.c
+ Simplified error message code in pngunknown. The simplification has the
+ useful side effect of avoiding a bogus warning generated by the latest
+ version of the Intel C compiler (it objects to
+ condition ? string-literal : string-literal).
+ Make autogen.sh work with automake 1.13 as well as 1.14. Do this by always
+ removing the 1.14 'compile' script but never checking for it.
+
+Version 1.6.7beta03 [October 19, 2013]
+ Added ARMv8 support (James Yu <james.yu at linaro.org>). Added file
+ arm/filter_neon_intrinsics.c; enable with -mfpu=neon.
+ Revised pngvalid to generate size images with as many filters as it can
+ manage, limited by the number of rows.
+ Cleaned up ARM NEON compilation handling. The tests are now in pngpriv.h
+ and detect the broken GCC compilers.
+
+Version 1.6.7beta04 [October 26, 2013]
+ Allow clang derived from older GCC versions to use ARM intrinsics. This
+ causes all clang builds that use -mfpu=neon to use the intrinsics code,
+ not the assembler code. This has only been tested on iOS 7. It may be
+ necessary to exclude some earlier clang versions but this seems unlikely.
+ Changed NEON implementation selection mechanism. This allows assembler
+ or intrinsics to be turned on at compile time during the build by defining
+ PNG_ARM_NEON_IMPLEMENTATION to the correct value (2 or 1). This macro
+ is undefined by default and the build type is selected in pngpriv.h.
+
+Version 1.6.7rc01 [November 2, 2013]
+ No changes.
+
+Version 1.6.7rc02 [November 7, 2013]
+ Fixed #include in filter_neon_intrinsics.c and ctype macros. The ctype char
+ checking macros take an unsigned char argument, not a signed char.
+
+Version 1.6.7 [November 14, 2013]
+ No changes.
+
+Version 1.6.8beta01 [November 24, 2013]
+ Moved prototype for png_handle_unknown() in pngpriv.h outside of
+ the #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED/#endif block.
+ Added "-Wall" to CFLAGS in contrib/pngminim/*/makefile
+ Conditionally compile some unused functions reported by -Wall in
+ pngminim.
+ Fixed 'minimal' builds. Various obviously useful minimal configurations
+ don't build because of missing contrib/libtests test programs and
+ overly complex dependencies in scripts/pnglibconf.dfa. This change
+ adds contrib/conftest/*.dfa files that can be used in automatic build
+ scripts to ensure that these configurations continue to build.
+ Enabled WRITE_INVERT and WRITE_PACK in contrib/pngminim/encoder.
+ Fixed pngvalid 'fail' function declaration on the Intel C Compiler.
+ This reverts to the previous 'static' implementation and works round
+ the 'unused static function' warning by using PNG_UNUSED().
+
+Version 1.6.8beta02 [November 30, 2013]
+ Removed or marked PNG_UNUSED some harmless "dead assignments" reported
+ by clang scan-build.
+ Changed tabs to 3 spaces in png_debug macros and changed '"%s"m'
+ to '"%s" m' to improve portability among compilers.
+ Changed png_free_default() to free() in pngtest.c
+
+Version 1.6.8rc01 [December 12, 2013]
+ Tidied up pngfix inits and fixed pngtest no-write builds.
+
+Version 1.6.8rc02 [December 14, 2013]
+ Handle zero-length PLTE chunk or NULL palette with png_error()
+ instead of png_chunk_report(), which by default issues a warning
+ rather than an error, leading to later reading from a NULL pointer
+ (png_ptr->palette) in png_do_expand_palette(). This is CVE-2013-6954
+ and VU#650142. Libpng-1.6.1 through 1.6.7 are vulnerable.
+ Libpng-1.6.0 and earlier do not have this bug.
+
+Version 1.6.8 [December 19, 2013]
+ No changes.
+
+Version 1.6.9beta01 [December 26, 2013]
+ Bookkeeping: Moved functions around (no changes). Moved transform
+ function definitions before the place where they are called so that
+ they can be made static. Move the intrapixel functions and the
+ grayscale palette builder out of the png?tran.c files. The latter
+ isn't a transform function and is no longer used internally, and the
+ former MNG specific functions are better placed in pngread/pngwrite.c
+ Made transform implementation functions static. This makes the internal
+ functions called by png_do_{read|write}_transformations static. On an
+ x86-64 DLL build (Gentoo Linux) this reduces the size of the text
+ segment of the DLL by 1208 bytes, about 0.6%. It also simplifies
+ maintenance by removing the declarations from pngpriv.h and allowing
+ easier changes to the internal interfaces.
+ Rebuilt configure scripts with automake-1.14.1 and autoconf-2.69
+ in the tar distributions.
+
+Version 1.6.9beta02 [January 1, 2014]
+ Added checks for libpng 1.5 to pngvalid.c. This supports the use of
+ this version of pngvalid in libpng 1.5
+ Merged with pngvalid.c from libpng-1.7 changes to create a single
+ pngvalid.c
+ Removed #error macro from contrib/tools/pngfix.c (Thomas Klausner).
+ Merged pngrio.c, pngtrans.c, pngwio.c, and pngerror.c with libpng-1.7.0
+ Merged libpng-1.7.0 changes to make no-interlace configurations work
+ with test programs.
+ Revised pngvalid.c to support libpng 1.5, which does not support the
+ PNG_MAXIMUM_INFLATE_WINDOW option, so #define it out when appropriate in
+ pngvalid.c
+ Allow unversioned links created on install to be disabled in configure.
+ In configure builds 'make install' changes/adds links like png.h
+ and libpng.a to point to the newly installed, versioned, files (e.g.
+ libpng17/png.h and libpng17.a). Three new configure options and some
+ rearrangement of Makefile.am allow creation of these links to be disabled.
+
+Version 1.6.9beta03 [January 10, 2014]
+ Removed potentially misleading warning from png_check_IHDR().
+
+Version 1.6.9beta04 [January 20, 2014]
+ Updated scripts/makefile.* to use CPPFLAGS (Cosmin).
+ Added clang attribute support (Cosmin).
+
+Version 1.6.9rc01 [January 28, 2014]
+ No changes.
+
+Version 1.6.9rc02 [January 30, 2014]
+ Quiet an uninitialized memory warning from VC2013 in png_get_png().
+
+Version 1.6.9 [February 6, 2014]
+
+Version 1.6.10beta01 [February 9, 2014]
+ Backported changes from libpng-1.7.0beta30 and beta31:
+ Fixed a large number of instances where PNGCBAPI was omitted from
+ function definitions.
+ Added pngimage test program for png_read_png() and png_write_png()
+ with two new test scripts.
+ Removed dependence on !PNG_READ_EXPAND_SUPPORTED for calling
+ png_set_packing() in png_read_png().
+ Fixed combination of ~alpha with shift. On read invert alpha, processing
+ occurred after shift processing, which causes the final values to be
+ outside the range that should be produced by the shift. Reversing the
+ order on read makes the two transforms work together correctly and mirrors
+ the order used on write.
+ Do not read invalid sBIT chunks. Previously libpng only checked sBIT
+ values on write, so a malicious PNG writer could therefore cause
+ the read code to return an invalid sBIT chunk, which might lead to
+ application errors or crashes. Such chunks are now skipped (with
+ chunk_benign_error).
+ Make png_read_png() and png_write_png() prototypes in png.h depend
+ upon PNG_READ_SUPPORTED and PNG_WRITE_SUPPORTED.
+ Support builds with unsupported PNG_TRANSFORM_* values. All of the
+ PNG_TRANSFORM_* values are always defined in png.h and, because they
+ are used for both read and write in some cases, it is not reliable
+ to #if out ones that are totally unsupported. This change adds error
+ detection in png_read_image() and png_write_image() to do a
+ png_app_error() if the app requests something that cannot be done
+ and it adds corresponding code to pngimage.c to handle such options
+ by not attempting to test them.
+
+Version 1.6.10beta02 [February 23, 2014]
+ Moved redefines of png_error(), png_warning(), png_chunk_error(),
+ and png_chunk_warning() from pngpriv.h to png.h to make them visible
+ to libpng-calling applications.
+ Moved OS dependent code from arm/arm_init.c, to allow the included
+ implementation of the ARM NEON discovery function to be set at
+ build-time and provide sample implementations from the current code in the
+ contrib/arm-neon subdirectory. The __linux__ code has also been changed to
+ compile and link on Android by using /proc/cpuinfo, and the old linux code
+ is in contrib/arm-neon/linux-auxv.c. The new code avoids POSIX and Linux
+ dependencies apart from opening /proc/cpuinfo and is C90 compliant.
+ Check for info_ptr == NULL early in png_read_end() so we don't need to
+ run all the png_handle_*() and depend on them to return if info_ptr == NULL.
+ This improves the performance of png_read_end(png_ptr, NULL) and makes
+ it more robust against future programming errors.
+ Check for __has_extension before using it in pngconf.h, to
+ support older Clang versions (Jeremy Sequoia).
+ Treat CRC error handling with png_set_crc_action(), instead of with
+ png_set_benign_errors(), which has been the case since libpng-1.6.0beta18.
+ Use a user warning handler in contrib/gregbook/readpng2.c instead of default,
+ so warnings will be put on stderr even if libpng has CONSOLE_IO disabled.
+ Added png_ptr->process_mode = PNG_READ_IDAT_MODE in png_push_read_chunk
+ after recognizing the IDAT chunk, which avoids an infinite loop while
+ reading a datastream whose first IDAT chunk is of zero-length.
+ This fixes CERT VU#684412 and CVE-2014-0333.
+ Don't recognize known sRGB profiles as sRGB if they have been hacked,
+ but don't reject them and don't issue a copyright violation warning.
+
+Version 1.6.10beta03 [February 25, 2014]
+ Moved some documentation from png.h to libpng.3 and libpng-manual.txt
+ Minor editing of contrib/arm-neon/README and contrib/examples/*.c
+
+Version 1.6.10rc01 [February 27, 2014]
+ Fixed typos in the manual and in scripts/pnglibconf.dfa (CFLAGS -> CPPFLAGS
+ and PNG_USR_CONFIG -> PNG_USER_CONFIG).
+
+Version 1.6.10rc02 [February 28, 2014]
+ Removed unreachable return statement after png_chunk_error()
+ in pngrutil.c
+
+Version 1.6.10rc03 [March 4, 2014]
+ Un-deprecated png_data_freer().
+
+Version 1.6.10 [March 6, 2014]
+ No changes.
+
+Version 1.6.11beta01 [March 17, 2014]
+ Use "if (value != 0)" instead of "if (value)" consistently.
+ Changed ZlibSrcDir from 1.2.5 to 1.2.8 in projects/vstudio.
+ Moved configuration information from the manual to the INSTALL file.
+
+Version 1.6.11beta02 [April 6, 2014]
+ Removed #if/#else/#endif from inside two pow() calls in pngvalid.c because
+ they were handled improperly by Portland Group's PGI-14.1 - PGI-14.3
+ when using its "__builtin_pow()" function.
+ Silence 'unused parameter' build warnings (Cosmin Truta).
+ $(CP) is now used alongside $(RM_F). Also, use 'copy' instead of 'cp'
+ where applicable, and applied other minor makefile changes (Cosmin).
+ Don't warn about invalid dimensions exceeding user limits (Cosmin).
+ Allow an easy replacement of the default pre-built configuration
+ header with a custom header, via the make PNGLIBCONF_H_PREBUILT
+ macro (Cosmin).
+
+Version 1.6.11beta03 [April 6, 2014]
+ Fixed a typo in pngrutil.c, introduced in libpng-1.5.6, that interferes
+ with "blocky" expansion of sub-8-bit interlaced PNG files (Eric Huss).
+ Optionally use __builtin_bswap16() in png_do_swap().
+
+Version 1.6.11beta04 [April 19, 2014]
+ Made progressive reading of interlaced images consistent with the
+ behavior of the sequential reader and consistent with the manual, by
+ moving some code out of the PNG_READ_INTERLACING_SUPPORTED blocks. The
+ row_callback now receives the proper pass number and unexpanded rows, when
+ png_combine_row() isn't built or used, and png_set_interlace_handling()
+ is not called.
+ Allow PNG_sRGB_PROFILE_CHECKING = (-1) to mean no sRGB profile checking.
+
+Version 1.6.11beta05 [April 26, 2014]
+ Do not reject ICC V2 profiles that lack padding (Kai-Uwe Behrmann).
+ Relocated closing bracket of the sRGB profile test loop to avoid getting
+ "Not recognizing known sRGB profile that has been edited" warning for
+ ICC V2 profiles that lack the MD5 signature in the profile header.
+
+Version 1.6.11beta06 [May 19, 2014]
+ Added PNG_SKIP_sRGB_CHECK_PROFILE choice for png_set_option().
+
+Version 1.6.11rc01 [May 27, 2014]
+ No changes.
+
+Version 1.6.11rc02 [June 3, 2014]
+ Test ZLIB_VERNUM instead of PNG_ZLIB_VERNUM in contrib/tools/pngfix.c
+
+Version 1.6.11 [June 5, 2014]
+ No changes.
+
+Version 1.6.12rc01 [June 6, 2014]
+ Relocated new code from 1.6.11beta06 in png.c to a point after the
+ declarations (Max Stepin).
+
+Version 1.6.12rc02 [June 7, 2014]
+ Changed file permissions of contrib/tools/intgamma.sh,
+ test-driver, and compile from 0644 to 0755 (Cosmin).
+
+Version 1.6.12rc03 [June 8, 2014]
+ Ensure "__has_attribute()" macro exists before trying to use it with
+ old clang compilers (MacPorts Ticket #43939).
+
+Version 1.6.12 [June 12, 2014]
+ No changes.
+
+Version 1.6.13beta01 [July 4, 2014]
+ Quieted -Wsign-compare and -Wclobber compiler warnings in
+ contrib/pngminus/*.c
+ Added "(void) png_ptr;" where needed in contrib/gregbook to quiet
+ compiler complaints about unused pointers.
+ Split a long output string in contrib/gregbook/rpng2-x.c.
+ Added "PNG_SET_OPTION" requirement for sRGB chunk support to pnglibconf.dfa,
+ Needed for write-only support (John Bowler).
+ Changed "if defined(__ARM_NEON__)" to
+ "if (defined(__ARM_NEON__) || defined(__ARM_NEON))" (James Wu).
+ Fixed clang no-warning builds: png_digit was defined but never used.
+
+Version 1.6.13beta02 [July 21, 2014]
+ Fixed an incorrect separator ("/" should be "\") in scripts/makefile.vcwin32
+ (bug report from Wolfgang S. Kechel). Bug was introduced in libpng-1.6.11.
+ Also fixed makefile.bc32, makefile.bor, makefile.msc, makefile.intel, and
+ makefile.tc3 similarly.
+
+Version 1.6.13beta03 [August 3, 2014]
+ Removed scripts/makefile.elf. It has not worked since libpng-1.5.0beta14
+ due to elimination of the PNG_FUNCTION_EXPORT and PNG_DATA_EXPORT
+ definitions from pngconf.h.
+ Ensure that CMakeLists.txt makes the target "lib" directory before making
+ symbolic link into it (SourceForge bug report #226 by Rolf Timmermans).
+
+Version 1.6.13beta04 [August 8, 2014]
+ Added opinion that the ECCN (Export Control Classification Number) for
+ libpng is EAR99 to the README file.
+ Eliminated use of "$<" in makefile explicit rules, when copying
+ $PNGLIBCONF_H_PREBUILT. This does not work on some versions of make;
+ bug introduced in libpng version 1.6.11.
+
+Version 1.6.13rc01 [August 14, 2014]
+ Made "ccopts" agree with "CFLAGS" in scripts/makefile.hp* and makefile.*sunu
+
+Version 1.6.13 [August 21, 2014]
+ No changes.
+
+Version 1.6.14beta01 [September 14, 2014]
+ Guard usage of png_ptr->options with #ifdef PNG_SET_OPTION_SUPPORTED.
+ Do not build contrib/tools/pngfix.c when PNG_SETJMP_NOT_SUPPORTED,
+ to allow "make" to complete without setjmp support (bug report by
+ Claudio Fontana)
+ Add "#include <setjmp.h>" to contrib/tools/pngfix.c (John Bowler)
+
+Version 1.6.14beta02 [September 18, 2014]
+ Use nanosleep() instead of usleep() in contrib/gregbook/rpng2-x.c
+ because usleep() is deprecated.
+ Define usleep() in contrib/gregbook/rpng2-x.c if not already defined
+ in unistd.h and nanosleep() is not available; fixes error introduced
+ in libpng-1.6.13.
+ Disable floating point exception handling in pngvalid.c when
+ PNG_FLOATING_ARITHMETIC is not supported (bug report by "zootus
+ at users.sourceforge.net").
+
+Version 1.6.14beta03 [September 19, 2014]
+ Define FE_DIVBYZERO, FE_INVALID, and FE_OVERFLOW in pngvalid.c if not
+ already defined. Revert floating point exception handling in pngvalid.c
+ to version 1.6.14beta01 behavior.
+
+Version 1.6.14beta04 [September 27, 2014]
+ Fixed incorrect handling of the iTXt compression flag in pngrutil.c
+ (bug report by Shunsaku Hirata). Bug was introduced in libpng-1.6.0.
+
+Version 1.6.14beta05 [October 1, 2014]
+ Added "option READ_iCCP enables READ_COMPRESSED_TEXT" to pnglibconf.dfa
+
+Version 1.6.14beta06 [October 5, 2014]
+ Removed unused "text_len" parameter from private function png_write_zTXt().
+ Conditionally compile some code in png_deflate_claim(), when
+ PNG_WARNINGS_SUPPORTED and PNG_ERROR_TEXT_SUPPORTED are disabled.
+ Replaced repeated code in pngpread.c with PNG_PUSH_SAVE_BUFFER_IF_FULL.
+ Added "chunk iTXt enables TEXT" and "chunk zTXt enables TEXT"
+ to pnglibconf.dfa.
+ Removed "option READ_COMPRESSED_TEXT enables READ_TEXT" from pnglibconf.dfa,
+ to make it possible to configure a libpng that supports iCCP but not TEXT.
+
+Version 1.6.14beta07 [October 7, 2014]
+ Removed "option WRITE_COMPRESSED_TEXT enables WRITE_TEXT" from pnglibconf.dfa
+ Only mark text chunks as written after successfully writing them.
+
+Version 1.6.14rc01 [October 15, 2014]
+ Fixed some typos in comments.
+
+Version 1.6.14rc02 [October 17, 2014]
+ Changed png_convert_to_rfc_1123() to png_convert_to_rfc_1123_buffer()
+ in the manual, to reflect the change made in libpng-1.6.0.
+ Updated README file to explain that direct access to the png_struct
+ and info_struct members has not been permitted since libpng-1.5.0.
+
+Version 1.6.14 [October 23, 2014]
+ No changes.
+
+Version 1.6.15beta01 [October 29, 2014]
+ Changed "if (!x)" to "if (x == 0)" and "if (x)" to "if (x != 0)"
+ Simplified png_free_data().
+ Added missing "ptr = NULL" after some instances of png_free().
+
+Version 1.6.15beta02 [November 1, 2014]
+ Changed remaining "if (!x)" to "if (x == 0)" and "if (x)" to "if (x != 0)"
+
+Version 1.6.15beta03 [November 3, 2014]
+ Added PNG_USE_ARM_NEON configuration flag (Marcin Juszkiewicz).
+
+Version 1.6.15beta04 [November 4, 2014]
+ Removed new PNG_USE_ARM_NEON configuration flag and made a one-line
+ revision to configure.ac to support ARM on aarch64 instead (John Bowler).
+
+Version 1.6.15beta05 [November 5, 2014]
+ Use png_get_libpng_ver(NULL) instead of PNG_LIBPNG_VER_STRING in
+ example.c, pngtest.c, and applications in the contrib directory.
+ Avoid out-of-bounds memory access in png_user_version_check().
+ Simplified and future-proofed png_user_version_check().
+ Fixed GCC unsigned int->float warnings. Various versions of GCC
+ seem to generate warnings when an unsigned value is implicitly
+ converted to double. This is probably a GCC bug but this change
+ avoids the issue by explicitly converting to (int) where safe.
+ Free all allocated memory in pngimage. The file buffer cache was left
+ allocated at the end of the program, harmless but it causes memory
+ leak reports from clang.
+ Fixed array size calculations to avoid warnings. At various points
+ in the code the number of elements in an array is calculated using
+ sizeof. This generates a compile time constant of type (size_t) which
+ is then typically assigned to an (unsigned int) or (int). Some versions
+ of GCC on 64-bit systems warn about the apparent narrowing, even though
+ the same compiler does apparently generate the correct, in-range,
+ numeric constant. This adds appropriate, safe, casts to make the
+ warnings go away.
+
+Version 1.6.15beta06 [November 6, 2014]
+ Reverted use png_get_libpng_ver(NULL) instead of PNG_LIBPNG_VER_STRING
+ in the manual, example.c, pngtest.c, and applications in the contrib
+ directory. It was incorrect advice.
+
+Version 1.6.15beta07 [November 7, 2014]
+ Removed #ifdef PNG_16BIT_SUPPORTED/#endif around png_product2(); it is
+ needed by png_reciprocal2().
+ Added #ifdef PNG_16BIT_SUPPORTED/#endif around png_log16bit() and
+ png_do_swap().
+ Changed all "#endif /* PNG_FEATURE_SUPPORTED */" to "#endif /* FEATURE */"
+
+Version 1.6.15beta08 [November 8, 2014]
+ More housecleaning in *.h
+
+Version 1.6.15rc01 [November 13, 2014]
+
+Version 1.6.15rc02 [November 14, 2014]
+ The macros passed in the command line to Borland make were ignored if
+ similarly-named macros were already defined in makefiles. This behavior
+ is different from POSIX make and other make programs. Surround the
+ macro definitions with ifndef guards (Cosmin).
+
+Version 1.6.15rc03 [November 16, 2014]
+ Added "-D_CRT_SECURE_NO_WARNINGS" to CFLAGS in scripts/makefile.vcwin32.
+ Removed the obsolete $ARCH variable from scripts/makefile.darwin.
+
+Version 1.6.15 [November 20, 2014]
+ No changes.
+
+Version 1.6.16beta01 [December 14, 2014]
+ Added ".align 2" to arm/filter_neon.S to support old GAS assemblers that
+ don't do alignment correctly.
+ Revised Makefile.am and scripts/symbols.dfn to work with MinGW/MSYS
+ (Bob Friesenhahn).
+
+Version 1.6.16beta02 [December 15, 2014]
+ Revised Makefile.am and scripts/*.dfn again to work with MinGW/MSYS;
+ renamed scripts/*.dfn to scripts/*.c (John Bowler).
+
+Version 1.6.16beta03 [December 21, 2014]
+ Quiet a "comparison always true" warning in pngstest.c (John Bowler).
+
+Version 1.6.16rc01 [December 21, 2014]
+ Restored a test on width that was removed from png.c at libpng-1.6.9
+ (Bug report by Alex Eubanks, CVE-2015-0973).
+
+Version 1.6.16rc02 [December 21, 2014]
+ Undid the update to pngrutil.c in 1.6.16rc01.
+
+Version 1.6.16rc03 [December 21, 2014]
+ Fixed an overflow in png_combine_row() with very wide interlaced images
+ (Bug report and fix by John Bowler, CVE-2014-9495).
+
+Version 1.6.16 [December 22, 2014]
+ No changes.
+
+Version 1.6.17beta01 [January 29, 2015]
+ Removed duplicate PNG_SAFE_LIMITS_SUPPORTED handling from pngconf.h
+ Corrected the width limit calculation in png_check_IHDR().
+ Removed user limits from pngfix. Also pass NULL pointers to
+ png_read_row to skip the unnecessary row de-interlace stuff.
+ Added testing of png_set_packing() to pngvalid.c
+ Regenerated configure scripts in the *.tar distributions with libtool-2.4.4
+ Implement previously untested cases of libpng transforms in pngvalid.c
+ Fixed byte order in png_do_read_filler() with 16-bit input. Previously
+ the high and low bytes of the filler, from png_set_filler() or from
+ png_set_add_alpha(), were read in the wrong order.
+ Made the check for out-of-range values in png_set_tRNS() detect
+ values that are exactly 2^bit_depth, and work on 16-bit platforms.
+ Merged some parts of libpng-1.6.17beta01 and libpng-1.7.0beta47.
+ Added #ifndef __COVERITY__ where needed in png.c, pngrutil.c and
+ pngset.c to avoid warnings about dead code.
+ Added "& 0xff" to many instances of expressions that are typecast
+ to (png_byte), to avoid Coverity warnings.
+
+Version 1.6.17beta02 [February 7, 2015]
+ Work around one more Coverity-scan dead-code warning.
+ Do not build png_product2() when it is unused.
+
+Version 1.6.17beta03 [February 17, 2015]
+ Display user limits in the output from pngtest.
+ Eliminated the PNG_SAFE_LIMITS macro and restored the 1-million-column
+ and 1-million-row default limits in pnglibconf.dfa, that can be reset
+ by the user at build time or run time. This provides a more robust
+ defense against DOS and as-yet undiscovered overflows.
+
+Version 1.6.17beta04 [February 21, 2015]
+ Added PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED macro, on by default.
+ Allow user to call png_get_IHDR() with NULL arguments (Reuben Hawkins).
+ Rebuilt configure scripts with automake-1.15 and libtool-2.4.6
+
+Version 1.6.17beta05 [February 25, 2015]
+ Restored compiling of png_reciprocal2 with PNG_NO_16BIT.
+
+Version 1.6.17beta06 [February 27, 2015]
+ Moved png_set_filter() prototype into a PNG_WRITE_SUPPORTED block
+ of png.h.
+ Avoid runtime checks when converting integer to png_byte with
+ Visual Studio (Sergey Kosarevsky)
+
+Version 1.6.17rc01 [March 4, 2015]
+ No changes.
+
+Version 1.6.17rc02 [March 9, 2015]
+ Removed some comments that the configure script did not handle
+ properly from scripts/pnglibconf.dfa and pnglibconf.h.prebuilt.
+ Free the unknown_chunks structure even when it contains no data.
+
+Version 1.6.17rc03 [March 12, 2015]
+ Updated CMakeLists.txt to add OSX framework, change YES/NO to ON/OFF
+ for consistency, and remove some useless tests (Alexey Petruchik).
+
+Version 1.6.17rc04 [March 16, 2015]
+ Remove pnglibconf.h, pnglibconf.c, and pnglibconf.out instead of
+ pnglibconf.* in "make clean" (Cosmin).
+ Fix bug in calculation of maxbits, in png_write_sBIT, introduced
+ in libpng-1.6.17beta01 (John Bowler).
+
+Version 1.6.17rc05 [March 21, 2015]
+ Define PNG_FILTER_* and PNG_FILTER_VALUE_* in png.h even when WRITE
+ is not supported (John Bowler). This fixes an error introduced in
+ libpng-1.6.17beta06.
+ Reverted "& 0xff" additions of version 1.6.17beta01. Libpng passes
+ the Coverity scan without them.
+
+Version 1.6.17rc06 [March 23, 2015]
+ Remove pnglibconf.dfn and pnglibconf.pre with "make clean".
+ Reformatted some "&0xff" instances to "& 0xff".
+ Fixed simplified 8-bit-linear to sRGB alpha. The calculated alpha
+ value was wrong. It's not clear if this affected the final stored
+ value; in the obvious code path the upper and lower 8-bits of the
+ alpha value were identical and the alpha was truncated to 8-bits
+ rather than dividing by 257 (John Bowler).
+
+Version 1.6.17 [March 26, 2015]
+ No changes.
+
+Version 1.6.18beta01 [April 1, 2015]
+ Removed PNG_SET_CHUNK_[CACHE|MALLOC]_LIMIT_SUPPORTED macros. They
+ have been combined with PNG_SET_USER_LIMITS_SUPPORTED (resolves
+ bug report by Andrew Church).
+ Fixed rgb_to_gray checks and added tRNS checks to pngvalid.c. This
+ fixes some arithmetic errors that caused some tests to fail on
+ some 32-bit platforms (Bug reports by Peter Breitenlohner [i686]
+ and Petr Gajdos [i586]).
+
+Version 1.6.18beta02 [April 26, 2015]
+ Suppressed some warnings from the Borland C++ 5.5.1/5.82 compiler
+ (Bug report by Viktor Szakats).
+
+Version 1.6.18beta03 [May 6, 2015]
+ Replaced "unexpected" with an integer (0xabadca11) in pngset.c
+ where a long was expected, to avoid a compiler warning when PNG_DEBUG > 1.
+ Added contrib/examples/simpleover.c, to demonstrate how to handle
+ alpha compositing of multiple images, using the "simplified API"
+ and an example PNG generation tool, contrib/examples/genpng.c
+ (John Bowler).
+
+Version 1.6.18beta04 [May 20, 2015]
+ PNG_RELEASE_BUILD replaces tests where the code depended on the build base
+ type and can be defined on the command line, allowing testing in beta
+ builds (John Bowler).
+ Avoid Coverity issue 80858 (REVERSE NULL) in pngtest.c PNG_DEBUG builds.
+ Avoid a harmless potential integer overflow in png_XYZ_from_xy() (Bug
+ report from Christopher Ferris).
+
+Version 1.6.18beta05 [May 31, 2015]
+ Backport filter selection code from libpng-1.7.0beta51, to combine
+ sub_row, up_row, avg_row, and paeth_row into try_row and tst_row.
+ Changed png_voidcast(), etc., to voidcast(), etc., in contrib/tools/pngfix.c
+ to avoid confusion with the libpng private macros.
+ Fixed old cut&paste bug in the weighted filter selection code in
+ pngwutil.c, introduced in libpng-0.95, March 1997.
+
+Version 1.6.18beta06 [June 1, 2015]
+ Removed WRITE_WEIGHTED_FILTERED code, to save a few kbytes of the
+ compiled library size. It never worked properly and as far as we can
+ tell, no one uses it. The png_set_filter_heuristics() and
+ png_set_filter_heuristics_fixed() APIs are retained but deprecated
+ and do nothing.
+
+Version 1.6.18beta07 [June 6, 2015]
+ Removed non-working progressive reader 'skip' function. This
+ function has apparently never been used. It was implemented
+ to support back-door modification of png_struct in libpng-1.4.x
+ but (because it does nothing and cannot do anything) was apparently
+ never tested (John Bowler).
+ Fixed cexcept.h in which GCC 5 now reports that one of the auto
+ variables in the Try macro needs to be volatile to prevent value
+ being lost over the setjmp (John Bowler).
+ Fixed NO_WRITE_FILTER and -Wconversion build breaks (John Bowler).
+ Fix g++ build breaks (John Bowler).
+ Quieted some Coverity issues in pngfix.c, png-fix-itxt.c, pngvalid.c,
+ pngstest.c, and pngimage.c. Most seem harmless, but png-fix-itxt
+ would only work with iTXt chunks with length 255 or less.
+ Added #ifdef's to contrib/examples programs so people don't try
+ to compile them without the minimum required support enabled
+ (suggested by Flavio Medeiros).
+
+Version 1.6.18beta08 [June 30, 2015]
+ Eliminated the final two Coverity defects (insecure temporary file
+ handling in contrib/libtests/pngstest.c; possible overflow of
+ unsigned char in contrib/tools/png-fix-itxt.c). To use the "secure"
+ file handling, define PNG_USE_MKSTEMP, otherwise "tmpfile()" will
+ be used.
+ Removed some unused WEIGHTED_FILTER macros from png.h and pngstruct.h
+
+Version 1.6.18beta09 [July 5, 2015]
+ Removed some useless typecasts from contrib/tools/png-fix-itxt.c
+ Fixed a new signed-unsigned comparison in pngrtran.c (Max Stepin).
+ Replaced arbitrary use of 'extern' with #define PNG_LINKAGE_*. To
+ preserve API compatibility, the new defines all default to "extern"
+ (requested by Jan Nijtmans).
+
+Version 1.6.18rc01 [July 9, 2015]
+ Belatedly added Mans Rullgard and James Yu to the list of Contributing
+ Authors.
+
+Version 1.6.18rc02 [July 12, 2015]
+ Restored unused FILTER_HEURISTIC macros removed at libpng-1.6.18beta08
+ to png.h to avoid compatibility warnings.
+
+Version 1.6.18rc03 [July 15, 2015]
+ Minor changes to the man page
+
+Version 1.6.18 [July 23, 2015]
+ No changes.
+
+Version 1.6.19beta01 [July 30, 2015]
+ Updated obsolete information about the simplified API macros in the
+ manual pages (Bug report by Arc Riley).
+ Avoid potentially dereferencing NULL info_ptr in png_info_init_3().
+ Rearranged png.h to put the major sections in the same order as
+ in libpng17.
+ Eliminated unused PNG_COST_SHIFT, PNG_WEIGHT_SHIFT, PNG_COST_FACTOR, and
+ PNG_WEIGHT_FACTOR macros.
+ Suppressed some warnings from the Borland C++ 5.5.1/5.82 compiler
+ (Bug report by Viktor Szakats). Several warnings remain and are
+ unavoidable, where we test for overflow.
+ Fixed potential leak of png_pixels in contrib/pngminus/pnm2png.c
+ Fixed uninitialized variable in contrib/gregbook/rpng2-x.c
+
+Version 1.6.19beta02 [August 19, 2015]
+ Moved config.h.in~ from the "libpng_autotools_files" list to the
+ "libpng_autotools_extra" list in autogen.sh because it was causing a
+ false positive for missing files (bug report by Robert C. Seacord).
+ Removed unreachable "break" statements in png.c, pngread.c, and pngrtran.c
+ to suppress clang warnings (Bug report by Viktor Szakats).
+ Fixed some bad links in the man page.
+ Changed "n bit" to "n-bit" in comments.
+ Added signed/unsigned 16-bit safety net. This removes the dubious
+ 0x8000 flag definitions on 16-bit systems. They aren't supported
+ yet the defs *probably* work, however it seems much safer to do this
+ and be advised if anyone, contrary to advice, is building libpng 1.6
+ on a 16-bit system. It also adds back various switch default clauses
+ for GCC; GCC errors out if they are not present (with an appropriately
+ high level of warnings).
+ Safely convert num_bytes to a png_byte in png_set_sig_bytes() (Robert
+ Seacord).
+ Fixed the recently reported 1's complement security issue by replacing
+ the value that is illegal in the PNG spec, in both signed and unsigned
+ values, with 0. Illegal unsigned values (anything greater than or equal
+ to 0x80000000) can still pass through, but since these are not illegal
+ in ANSI-C (unlike 0x80000000 in the signed case) the checking that
+ occurs later can catch them (John Bowler).
+
+Version 1.6.19beta03 [September 26, 2015]
+ Fixed png_save_int_32 when int is not 2's complement (John Bowler).
+ Updated libpng16 with all the recent test changes from libpng17,
+ including changes to pngvalid.c to ensure that the original,
+ distributed, version of contrib/visupng/cexcept.h can be used
+ (John Bowler).
+ pngvalid contains the correction to the use of SAVE/STORE_
+ UNKNOWN_CHUNKS; a bug revealed by changes in libpng 1.7. More
+ tests contain the --strict option to detect warnings and the
+ pngvalid-standard test has been corrected so that it does not
+ turn on progressive-read. There is a separate test which does
+ that. (John Bowler)
+ Also made some signed/unsigned fixes.
+ Make pngstest error limits version specific. Splitting the machine
+ generated error structs out to a file allows the values to be updated
+ without changing pngstest.c itself. Since libpng 1.6 and 1.7 have
+ slightly different error limits this simplifies maintenance. The
+ makepngs.sh script has also been updated to more accurately reflect
+ current problems in libpng 1.7 (John Bowler).
+ Incorporated new test PNG files into make check. tests/pngstest-*
+ are changed so that the new test files are divided into 8 groups by
+ gamma and alpha channel. These tests have considerably better code
+ and pixel-value coverage than contrib/pngsuite; however,coverage is
+ still incomplete (John Bowler).
+ Removed the '--strict' in 1.6 because of the double-gamma-correction
+ warning, updated pngstest-errors.h for the errors detected with the
+ new contrib/testspngs PNG test files (John Bowler).
+
+Version 1.6.19beta04 [October 15, 2015]
+ Worked around rgb-to-gray issues in libpng 1.6. The previous
+ attempts to ignore the errors in the code aren't quite enough to
+ deal with the 'channel selection' encoding added to libpng 1.7; abort.
+ pngvalid.c is changed to drop this encoding in prior versions.
+ Fixed 'pow' macros in pngvalid.c. It is legal for 'pow' to be a
+ macro, therefore the argument list cannot contain preprocessing
+ directives. Make sure pow is a function where this happens. This is
+ a minimal safe fix, the issue only arises in non-performance-critical
+ code (bug report by Curtis Leach, fix by John Bowler).
+ Added sPLT support to pngtest.c
+
+Version 1.6.19rc01 [October 23, 2015]
+ No changes.
+
+Version 1.6.19rc02 [October 31, 2015]
+ Prevent setting or writing over-length PLTE chunk (Cosmin Truta).
+ Silently truncate over-length PLTE chunk while reading.
+ Libpng incorrectly calculated the output rowbytes when the application
+ decreased either the number of channels or the bit depth (or both) in
+ a user transform. This was safe; libpng overallocated buffer space
+ (potentially by quite a lot; up to 4 times the amount required) but,
+ from 1.5.4 on, resulted in a png_error (John Bowler).
+
+Version 1.6.19rc03 [November 3, 2015]
+ Fixed some inconsequential cut-and-paste typos in png_set_cHRM_XYZ_fixed().
+ Clarified COPYRIGHT information to state explicitly that versions
+ are derived from previous versions.
+ Removed much of the long list of previous versions from png.h and
+ libpng.3.
+
+Version 1.6.19rc04 [November 5, 2015]
+ Fixed new bug with CRC error after reading an over-length palette
+ (bug report by Cosmin Truta) (CVE-2015-8126).
+
+Version 1.6.19 [November 12, 2015]
+ Cleaned up coding style in png_handle_PLTE().
+
+Version 1.6.20beta01 [November 20, 2015]
+ Avoid potential pointer overflow/underflow in png_handle_sPLT() and
+ png_handle_pCAL() (Bug report by John Regehr).
+
+Version 1.6.20beta02 [November 23, 2015]
+ Fixed incorrect implementation of png_set_PLTE() that uses png_ptr
+ not info_ptr, that left png_set_PLTE() open to the CVE-2015-8126
+ vulnerability.
+
+Version 1.6.20beta03 [November 24, 2015]
+ Backported tests from libpng-1.7.0beta69.
+
+Version 1.6.20rc01 [November 26, 2015]
+ Fixed an error in handling of bad zlib CMINFO field in pngfix, found by
+ American Fuzzy Lop, reported by Brian Carpenter. inflate() doesn't
+ immediately fault a bad CMINFO field; instead a 'too far back' error
+ happens later (at least some times). pngfix failed to limit CMINFO to
+ the allowed values but then assumed that window_bits was in range,
+ triggering an assert. The bug is mostly harmless; the PNG file cannot
+ be fixed.
+
+Version 1.6.20rc02 [November 29, 2015]
+ In libpng 1.6 zlib initialization was changed to use the window size
+ in the zlib stream, not a fixed value. This causes some invalid images,
+ where CINFO is too large, to display 'correctly' if the rest of the
+ data is valid. This provides a workaround for zlib versions where the
+ error arises (ones that support the API change to use the window size
+ in the stream).
+
+Version 1.6.20 [December 3, 2015]
+ No changes.
+
+Send comments/corrections/commendations to png-mng-implement at lists.sf.net
+(subscription required; visit
+https://lists.sourceforge.net/lists/listinfo/png-mng-implement
+to subscribe)
+or to glennrp at users.sourceforge.net
+
+Glenn R-P
+#endif
diff --git a/libpng/CMakeLists.txt b/libpng/CMakeLists.txt
new file mode 100644
index 0000000..7bc49c5
--- /dev/null
+++ b/libpng/CMakeLists.txt
@@ -0,0 +1,374 @@
+# CMakeLists.txt
+
+# Copyright (C) 2007-2015 Glenn Randers-Pehrson
+
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+
+cmake_minimum_required(VERSION 2.4.4)
+set(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS true)
+
+set(CMAKE_CONFIGURATION_TYPES "Release;Debug;MinSizeRel;RelWithDebInfo")
+
+project(libpng C)
+enable_testing()
+
+set(PNGLIB_MAJOR 1)
+set(PNGLIB_MINOR 6)
+set(PNGLIB_RELEASE 20)
+set(PNGLIB_NAME libpng${PNGLIB_MAJOR}${PNGLIB_MINOR})
+set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_RELEASE})
+
+# needed packages
+find_package(ZLIB REQUIRED)
+include_directories(${ZLIB_INCLUDE_DIR})
+
+if(NOT WIN32)
+ find_library(M_LIBRARY
+ NAMES m
+ PATHS /usr/lib /usr/local/lib
+ )
+ if(NOT M_LIBRARY)
+ message(STATUS "math lib 'libm' not found; floating point support disabled")
+ endif()
+else()
+ # not needed on windows
+ set(M_LIBRARY "")
+endif()
+
+# COMMAND LINE OPTIONS
+option(PNG_SHARED "Build shared lib" ON)
+option(PNG_STATIC "Build static lib" ON)
+option(PNG_TESTS "Build libpng tests" ON)
+
+# Many more configuration options could be added here
+option(PNG_FRAMEWORK "Build OS X framework" OFF)
+option(PNG_DEBUG "Build with debug output" OFF)
+option(PNGARG "Disable ANSI-C prototypes" OFF)
+
+# SET LIBNAME
+set(PNG_LIB_NAME png${PNGLIB_MAJOR}${PNGLIB_MINOR})
+
+# to distinguish between debug and release lib
+set(CMAKE_DEBUG_POSTFIX "d")
+
+# Use the prebuilt pnglibconf.h file from the scripts folder
+# TODO: fix this by building with awk; without this no cmake build can be
+# configured directly (to do so indirectly use your local awk to build a
+# pnglibconf.h in the build directory.)
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt
+ ${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h)
+include_directories(${CMAKE_CURRENT_BINARY_DIR})
+
+# OUR SOURCES
+set(libpng_public_hdrs
+ png.h
+ pngconf.h
+ ${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h
+)
+set(libpng_sources
+ ${libpng_public_hdrs}
+ pngdebug.h
+ pnginfo.h
+ pngpriv.h
+ pngstruct.h
+ png.c
+ pngerror.c
+ pngget.c
+ pngmem.c
+ pngpread.c
+ pngread.c
+ pngrio.c
+ pngrtran.c
+ pngrutil.c
+ pngset.c
+ pngtrans.c
+ pngwio.c
+ pngwrite.c
+ pngwtran.c
+ pngwutil.c
+)
+set(pngtest_sources
+ pngtest.c
+)
+set(pngvalid_sources
+ contrib/libtests/pngvalid.c
+)
+set(pngstest_sources
+ contrib/libtests/pngstest.c
+)
+# SOME NEEDED DEFINITIONS
+
+if(MSVC)
+ add_definitions(-D_CRT_SECURE_NO_DEPRECATE)
+endif(MSVC)
+
+if(PNG_DEBUG)
+ add_definitions(-DPNG_DEBUG)
+endif()
+
+# NOW BUILD OUR TARGET
+include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${ZLIB_INCLUDE_DIR})
+
+unset(PNG_LIB_TARGETS)
+
+if(PNG_SHARED)
+ add_library(${PNG_LIB_NAME} SHARED ${libpng_sources})
+ set(PNG_LIB_TARGETS ${PNG_LIB_NAME})
+ if(MSVC)
+ # msvc does not append 'lib' - do it here to have consistent name
+ set_target_properties(${PNG_LIB_NAME} PROPERTIES PREFIX "lib")
+ set_target_properties(${PNG_LIB_NAME} PROPERTIES IMPORT_PREFIX "lib")
+ endif()
+ target_link_libraries(${PNG_LIB_NAME} ${ZLIB_LIBRARY} ${M_LIBRARY})
+endif()
+
+if(PNG_STATIC)
+ # does not work without changing name
+ set(PNG_LIB_NAME_STATIC ${PNG_LIB_NAME}_static)
+ add_library(${PNG_LIB_NAME_STATIC} STATIC ${libpng_sources})
+ list(APPEND PNG_LIB_TARGETS ${PNG_LIB_NAME_STATIC})
+ if(MSVC)
+ # msvc does not append 'lib' - do it here to have consistent name
+ set_target_properties(${PNG_LIB_NAME_STATIC} PROPERTIES PREFIX "lib")
+ endif()
+ target_link_libraries(${PNG_LIB_NAME_STATIC} ${ZLIB_LIBRARY} ${M_LIBRARY})
+endif()
+
+if(PNG_FRAMEWORK)
+ set(PNG_LIB_NAME_FRAMEWORK ${PNG_LIB_NAME}_framework)
+ add_library(${PNG_LIB_NAME_FRAMEWORK} SHARED ${libpng_sources})
+ list(APPEND PNG_LIB_TARGETS ${PNG_LIB_NAME_FRAMEWORK})
+ set_target_properties(${PNG_LIB_NAME_FRAMEWORK} PROPERTIES
+ FRAMEWORK TRUE
+ FRAMEWORK_VERSION ${PNGLIB_VERSION}
+ MACOSX_FRAMEWORK_SHORT_VERSION_STRING ${PNGLIB_MAJOR}.${PNGLIB_MINOR}
+ MACOSX_FRAMEWORK_BUNDLE_VERSION ${PNGLIB_VERSION}
+ MACOSX_FRAMEWORK_IDENTIFIER org.libpng.libpng
+ XCODE_ATTRIBUTE_INSTALL_PATH "@rpath"
+ PUBLIC_HEADER "${libpng_public_hdrs}"
+ OUTPUT_NAME png)
+ target_link_libraries(${PNG_LIB_NAME_FRAMEWORK} ${ZLIB_LIBRARY} ${M_LIBRARY})
+endif()
+
+if(NOT PNG_LIB_TARGETS)
+ message(SEND_ERROR
+ "No library variant selected to build. "
+ "Please enable at least one of the following options: "
+ " PNG_STATIC, PNG_SHARED, PNG_FRAMEWORK")
+endif()
+
+if(PNG_SHARED AND WIN32)
+ set_target_properties(${PNG_LIB_NAME} PROPERTIES DEFINE_SYMBOL PNG_BUILD_DLL)
+endif()
+
+if(PNG_TESTS AND PNG_SHARED)
+ # does not work with msvc due to png_lib_ver issue
+ add_executable(pngtest ${pngtest_sources})
+ target_link_libraries(pngtest ${PNG_LIB_NAME})
+ add_test(pngtest ./pngtest ${CMAKE_CURRENT_SOURCE_DIR}/pngtest.png)
+ #
+ add_executable(pngvalid ${pngvalid_sources})
+ target_link_libraries(pngvalid ${PNG_LIB_NAME})
+ add_test(pngvalid ./pngvalid)
+ add_executable(pngstest ${pngstest_sources})
+ target_link_libraries(pngstest ${PNG_LIB_NAME})
+ add_test(pngstest ./pngstest
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g01.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g02.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g04.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g08.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g16.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn2c08.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn2c16.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p01.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p02.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p04.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p08.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn4a08.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn4a16.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn6a08.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn6a16.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn0g01.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn0g02.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn0g04.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn2c16.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn3p08.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbgn2c16.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbgn3p08.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbrn2c08.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbwn0g16.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbwn3p08.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbyn3p08.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp0n0g08.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp0n2c08.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp0n3p08.png
+ ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp1n3p08.png
+ )
+endif()
+
+# Ensure the CMAKE_LIBRARY_OUTPUT_DIRECTORY is set
+IF(NOT CMAKE_LIBRARY_OUTPUT_DIRECTORY)
+ SET(CMAKE_LIBRARY_OUTPUT_DIRECTORY "lib")
+ENDIF(NOT CMAKE_LIBRARY_OUTPUT_DIRECTORY)
+
+# Set a variable with CMake code which:
+# Creates a symlink from src to dest (if possible) or alternatively
+# copies if different.
+macro(CREATE_SYMLINK SRC_FILE DEST_FILE)
+ FILE(REMOVE ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE})
+ if(WIN32 AND NOT CYGWIN AND NOT MSYS)
+ ADD_CUSTOM_COMMAND(
+ OUTPUT ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE} ${CMAKE_CURRENT_BINARY_DIR}/${DEST_FILE}
+ COMMAND ${CMAKE_COMMAND} -E copy_if_different "${SRC_FILE}" ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE}
+ COMMAND ${CMAKE_COMMAND} -E copy_if_different "${SRC_FILE}" ${CMAKE_CURRENT_BINARY_DIR}/${DEST_FILE}
+ DEPENDS ${PNG_LIB_TARGETS}
+ )
+ ADD_CUSTOM_TARGET(${DEST_FILE}_COPY ALL DEPENDS ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE})
+ else(WIN32 AND NOT CYGWIN AND NOT MSYS)
+ get_filename_component(LINK_TARGET "${SRC_FILE}" NAME)
+ execute_process(COMMAND ${CMAKE_COMMAND} -E make_directory ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_LIBRARY_OUTPUT_DIRECTORY})
+ execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink "${LINK_TARGET}" ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+ execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink "${LINK_TARGET}" ${DEST_FILE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+ endif(WIN32 AND NOT CYGWIN AND NOT MSYS)
+endmacro()
+
+# libpng is a library so default to 'lib'
+if(NOT DEFINED CMAKE_INSTALL_LIBDIR)
+ set(CMAKE_INSTALL_LIBDIR lib)
+endif(NOT DEFINED CMAKE_INSTALL_LIBDIR)
+
+# CREATE PKGCONFIG FILES
+# we use the same files like ./configure, so we have to set its vars
+# Only do this on Windows for Cygwin - the files don't make much sense outside
+# a UNIX look alike
+if(NOT WIN32 OR CYGWIN OR MINGW)
+ set(prefix ${CMAKE_INSTALL_PREFIX})
+ set(exec_prefix ${CMAKE_INSTALL_PREFIX})
+ set(libdir ${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR})
+ set(includedir ${CMAKE_INSTALL_PREFIX}/include)
+ set(LIBS "-lz -lm")
+ configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng.pc.in
+ ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc @ONLY)
+ CREATE_SYMLINK(${PNGLIB_NAME}.pc libpng.pc)
+
+ configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng-config.in
+ ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config @ONLY)
+ CREATE_SYMLINK(${PNGLIB_NAME}-config libpng-config)
+endif(NOT WIN32 OR CYGWIN OR MINGW)
+
+# SET UP LINKS
+if(PNG_SHARED)
+ set_target_properties(${PNG_LIB_NAME} PROPERTIES
+# VERSION 16.${PNGLIB_RELEASE}.1.6.20
+ VERSION 16.${PNGLIB_RELEASE}.0
+ SOVERSION 16
+ CLEAN_DIRECT_OUTPUT 1)
+endif()
+if(PNG_STATIC)
+ # MSVC doesn't use a different file extension for shared vs. static
+ # libs. We are able to change OUTPUT_NAME to remove the _static
+ # for all other platforms.
+ if(NOT MSVC)
+ set_target_properties(${PNG_LIB_NAME_STATIC} PROPERTIES
+ OUTPUT_NAME ${PNG_LIB_NAME}
+ CLEAN_DIRECT_OUTPUT 1)
+ endif()
+endif()
+
+# If CMake > 2.4.x, we set a variable used below to export
+# targets to an export file.
+# TODO: Use VERSION_GREATER after our cmake_minimum_required >= 2.6.2
+if(CMAKE_MAJOR_VERSION GREATER 1 AND CMAKE_MINOR_VERSION GREATER 4)
+ set(PNG_EXPORT_RULE EXPORT libpng)
+elseif(CMAKE_MAJOR_VERSION GREATER 2) # future proof
+ set(PNG_EXPORT_RULE EXPORT libpng)
+endif()
+
+# INSTALL
+if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )
+ install(TARGETS ${PNG_LIB_TARGETS}
+ ${PNG_EXPORT_RULE}
+ RUNTIME DESTINATION bin
+ LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+ ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
+ FRAMEWORK DESTINATION ${CMAKE_INSTALL_LIBDIR})
+
+ if(PNG_SHARED)
+ # Create a symlink for libpng.dll.a => libpng16.dll.a on Cygwin
+ if(CYGWIN OR MINGW)
+ get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME} LOCATION_${CMAKE_BUILD_TYPE})
+ CREATE_SYMLINK(${BUILD_TARGET_LOCATION} libpng${CMAKE_IMPORT_LIBRARY_SUFFIX})
+ install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_IMPORT_LIBRARY_SUFFIX}
+ DESTINATION ${CMAKE_INSTALL_LIBDIR})
+ endif(CYGWIN OR MINGW)
+
+ if(NOT WIN32)
+ get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME} LOCATION_${CMAKE_BUILD_TYPE})
+ CREATE_SYMLINK(${BUILD_TARGET_LOCATION} libpng${CMAKE_SHARED_LIBRARY_SUFFIX})
+ install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_SHARED_LIBRARY_SUFFIX}
+ DESTINATION ${CMAKE_INSTALL_LIBDIR})
+ endif(NOT WIN32)
+ endif(PNG_SHARED)
+
+ if(PNG_STATIC)
+ if(NOT WIN32 OR CYGWIN OR MINGW)
+ get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME_STATIC} LOCATION_${CMAKE_BUILD_TYPE})
+ CREATE_SYMLINK(${BUILD_TARGET_LOCATION} libpng${CMAKE_STATIC_LIBRARY_SUFFIX})
+ install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_STATIC_LIBRARY_SUFFIX}
+ DESTINATION ${CMAKE_INSTALL_LIBDIR})
+ endif(NOT WIN32 OR CYGWIN OR MINGW)
+ endif()
+endif()
+
+if(NOT SKIP_INSTALL_HEADERS AND NOT SKIP_INSTALL_ALL )
+ install(FILES ${libpng_public_hdrs} DESTINATION include)
+ install(FILES ${libpng_public_hdrs} DESTINATION include/${PNGLIB_NAME})
+endif()
+if(NOT SKIP_INSTALL_EXECUTABLES AND NOT SKIP_INSTALL_ALL )
+ if(NOT WIN32 OR CYGWIN OR MINGW)
+ install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng-config DESTINATION bin)
+ install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config
+ DESTINATION bin)
+ endif(NOT WIN32 OR CYGWIN OR MINGW)
+endif()
+
+if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )
+ # Install man pages
+ if(NOT PNG_MAN_DIR)
+ set(PNG_MAN_DIR "share/man")
+ endif()
+ install(FILES libpng.3 libpngpf.3 DESTINATION ${PNG_MAN_DIR}/man3)
+ install(FILES png.5 DESTINATION ${PNG_MAN_DIR}/man5)
+ # Install pkg-config files
+ if(NOT WIN32 OR CYGWIN OR MINGW)
+ install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng.pc
+ DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)
+ install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng-config
+ DESTINATION bin)
+ install(FILES ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc
+ DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)
+ install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config
+ DESTINATION bin)
+ endif(NOT WIN32 OR CYGWIN OR MINGW)
+endif()
+
+# On versions of CMake that support it, create an export file CMake
+# users can include() to import our targets
+if(PNG_EXPORT_RULE AND NOT SKIP_INSTALL_EXPORT AND NOT SKIP_INSTALL_ALL )
+ install(EXPORT libpng DESTINATION lib/libpng FILE lib${PNG_LIB_NAME}.cmake)
+endif()
+
+# what's with libpng-manual.txt and all the extra files?
+
+# UNINSTALL
+# do we need this?
+
+# DIST
+# do we need this?
+
+# to create msvc import lib for mingw compiled shared lib
+# pexports libpng.dll > libpng.def
+# lib /def:libpng.def /machine:x86
+
diff --git a/libpng/CleanSpec.mk b/libpng/CleanSpec.mk
new file mode 100644
index 0000000..b84e1b6
--- /dev/null
+++ b/libpng/CleanSpec.mk
@@ -0,0 +1,49 @@
+# Copyright (C) 2007 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+# If you don't need to do a full clean build but would like to touch
+# a file or delete some intermediate files, add a clean step to the end
+# of the list. These steps will only be run once, if they haven't been
+# run before.
+#
+# E.g.:
+# $(call add-clean-step, touch -c external/sqlite/sqlite3.h)
+# $(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libz_intermediates)
+#
+# Always use "touch -c" and "rm -f" or "rm -rf" to gracefully deal with
+# files that are missing or have been moved.
+#
+# Use $(PRODUCT_OUT) to get to the "out/target/product/blah/" directory.
+# Use $(OUT_DIR) to refer to the "out" directory.
+#
+# If you need to re-do something that's already mentioned, just copy
+# the command and add it to the bottom of the list. E.g., if a change
+# that you made last week required touching a file and a change you
+# made today requires touching the same file, just copy the old
+# touch step and add it to the end of the list.
+#
+# ************************************************
+# NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
+# ************************************************
+
+# For example:
+#$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS/AndroidTests_intermediates)
+#$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/JAVA_LIBRARIES/core_intermediates)
+#$(call add-clean-step, find $(OUT_DIR) -type f -name "IGTalkSession*" -print0 | xargs -0 rm -f)
+#$(call add-clean-step, rm -rf $(PRODUCT_OUT)/data/*)
+
+# ************************************************
+# NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
+# ************************************************
diff --git a/libpng/INSTALL b/libpng/INSTALL
new file mode 100644
index 0000000..a294ffe
--- /dev/null
+++ b/libpng/INSTALL
@@ -0,0 +1,407 @@
+
+Installing libpng
+
+Contents
+
+ I. Simple installation
+ II. Rebuilding the configure scripts
+ III. Using scripts/makefile*
+ IV. Using cmake
+ V. Directory structure
+ VI. Building with project files
+ VII. Building with makefiles
+VIII. Configuring libpng for 16-bit platforms
+ IX. Configuring for DOS
+ X. Configuring for Medium Model
+ XI. Prepending a prefix to exported symbols
+ XII. Configuring for compiler xxx:
+XIII. Removing unwanted object code
+ XIV. Changes to the build and configuration of libpng in libpng-1.5.x
+ XV. Setjmp/longjmp issues
+ XVI. Other sources of information about libpng
+
+I. Simple installation
+
+On Unix/Linux and similar systems, you can simply type
+
+ ./configure [--prefix=/path]
+ make check
+ make install
+
+and ignore the rest of this document. "/path" is the path to the directory
+where you want to install the libpng "lib", "include", and "bin"
+subdirectories.
+
+If you downloaded a GIT clone, you will need to run ./autogen.sh before
+running ./configure, to create "configure" and "Makefile.in" which are
+not included in the GIT repository.
+
+Note that "configure" is only included in the "*.tar" distributions and not
+in the "*.zip" or "*.7z" distributions. If you downloaded one of those
+distributions, see "Building with project files" or "Building with makefiles",
+below.
+
+II. Rebuilding the configure scripts
+
+If configure does not work on your system, or if you have a need to
+change configure.ac or Makefile.am, and you have a reasonably
+up-to-date set of tools, running ./autogen.sh in a git clone before
+running ./configure may fix the problem. To be really sure that you
+aren't using any of the included pre-built scripts, you can do this:
+
+ ./configure --enable-maintainer-mode
+ make maintainer-clean
+ ./autogen.sh --maintainer --clean
+ ./autogen.sh --maintainer
+ ./configure [--prefix=/path] [other options]
+ make
+ make install
+ make check
+
+III. Using scripts/makefile*
+
+Instead, you can use one of the custom-built makefiles in the
+"scripts" directory
+
+ cp scripts/pnglibconf.h.prebuilt pnglibconf.h
+ cp scripts/makefile.system makefile
+ make test
+ make install
+
+The files that are presently available in the scripts directory
+are listed and described in scripts/README.txt.
+
+Or you can use one of the "projects" in the "projects" directory.
+
+Before installing libpng, you must first install zlib, if it
+is not already on your system. zlib can usually be found
+wherever you got libpng; otherwise go to http://zlib.net. You can place
+zlib in in the same directory as libpng or in another directory.
+
+If your system already has a preinstalled zlib you will still need
+to have access to the zlib.h and zconf.h include files that
+correspond to the version of zlib that's installed.
+
+If you wish to test with a particular zlib that is not first in the
+standard library search path, put ZLIBLIB, ZLIBINC, CPPFLAGS, LDFLAGS,
+and LD_LIBRARY_PATH in your environment before running "make test"
+or "make distcheck":
+
+ZLIBLIB=/path/to/lib export ZLIBLIB
+ZLIBINC=/path/to/include export ZLIBINC
+CPPFLAGS="-I$ZLIBINC" export CPPFLAGS
+LDFLAGS="-L$ZLIBLIB" export LDFLAGS
+LD_LIBRARY_PATH="$ZLIBLIB:$LD_LIBRARY_PATH" export LD_LIBRARY_PATH
+
+If you are using one of the makefile scripts, put ZLIBLIB and ZLIBINC
+in your environment and type "make ZLIBLIB=$ZLIBLIB ZLIBINC=$ZLIBINC test".
+
+IV. Using cmake
+
+If you want to use "cmake" (see www.cmake.org), type
+
+ cmake . -DCMAKE_INSTALL_PREFIX=/path
+ make
+ make install
+
+As when using the simple configure method described above, "/path" points to
+the installation directory where you want to put the libpng "lib", "include",
+and "bin" subdirectories.
+
+V. Directory structure
+
+You can rename the directories that you downloaded (they
+might be called "libpng-x.y.z" or "libpngNN" and "zlib-1.2.8"
+or "zlib128") so that you have directories called "zlib" and "libpng".
+
+Your directory structure should look like this:
+
+ .. (the parent directory)
+ libpng (this directory)
+ INSTALL (this file)
+ README
+ *.h, *.c => libpng source files
+ CMakeLists.txt => "cmake" script
+ configuration files:
+ configure.ac, configure, Makefile.am, Makefile.in,
+ autogen.sh, config.guess, ltmain.sh, missing, libpng.pc.in,
+ libpng-config.in, aclocal.m4, config.h.in, config.sub,
+ depcomp, install-sh, mkinstalldirs, test-pngtest.sh
+ contrib
+ arm-neon, conftest, examples, gregbook, libtests, pngminim,
+ pngminus, pngsuite, tools, visupng
+ projects
+ cbuilder5, owatcom, visualc71, vstudio, xcode
+ scripts
+ makefile.*
+ *.def (module definition files)
+ etc.
+ pngtest.png
+ etc.
+ zlib
+ README, *.h, *.c contrib, etc.
+
+If the line endings in the files look funny, you may wish to get the other
+distribution of libpng. It is available in both tar.gz (UNIX style line
+endings) and zip (DOS style line endings) formats.
+
+VI. Building with project files
+
+If you are building libpng with MSVC, you can enter the
+libpng projects\visualc71 or vstudio directory and follow the instructions
+in README.txt.
+
+Otherwise enter the zlib directory and follow the instructions in zlib/README,
+then come back here and run "configure" or choose the appropriate
+makefile.sys in the scripts directory.
+
+VII. Building with makefiles
+
+Copy the file (or files) that you need from the
+scripts directory into this directory, for example
+
+ MSDOS example: copy scripts\makefile.msc makefile
+ copy scripts\pnglibconf.h.prebuilt pnglibconf.h
+ UNIX example: cp scripts/makefile.std makefile
+ cp scripts/pnglibconf.h.prebuilt pnglibconf.h
+
+Read the makefile to see if you need to change any source or
+target directories to match your preferences.
+
+Then read pnglibconf.dfa to see if you want to make any configuration
+changes.
+
+Then just run "make" which will create the libpng library in
+this directory and "make test" which will run a quick test that reads
+the "pngtest.png" file and writes a "pngout.png" file that should be
+identical to it. Look for "9782 zero samples" in the output of the
+test. For more confidence, you can run another test by typing
+"pngtest pngnow.png" and looking for "289 zero samples" in the output.
+Also, you can run "pngtest -m contrib/pngsuite/*.png" and compare
+your output with the result shown in contrib/pngsuite/README.
+
+Most of the makefiles will allow you to run "make install" to
+put the library in its final resting place (if you want to
+do that, run "make install" in the zlib directory first if necessary).
+Some also allow you to run "make test-installed" after you have
+run "make install".
+
+VIII. Configuring libpng for 16-bit platforms
+
+You will want to look into zconf.h to tell zlib (and thus libpng) that
+it cannot allocate more than 64K at a time. Even if you can, the memory
+won't be accessible. So limit zlib and libpng to 64K by defining MAXSEG_64K.
+
+IX. Configuring for DOS
+
+For DOS users who only have access to the lower 640K, you will
+have to limit zlib's memory usage via a png_set_compression_mem_level()
+call. See zlib.h or zconf.h in the zlib library for more information.
+
+X. Configuring for Medium Model
+
+Libpng's support for medium model has been tested on most of the popular
+compilers. Make sure MAXSEG_64K gets defined, USE_FAR_KEYWORD gets
+defined, and FAR gets defined to far in pngconf.h, and you should be
+all set. Everything in the library (except for zlib's structure) is
+expecting far data. You must use the typedefs with the p or pp on
+the end for pointers (or at least look at them and be careful). Make
+note that the rows of data are defined as png_bytepp, which is
+an "unsigned char far * far *".
+
+XI. Prepending a prefix to exported symbols
+
+Starting with libpng-1.6.0, you can configure libpng (when using the
+"configure" script) to prefix all exported symbols by means of the
+configuration option "--with-libpng-prefix=FOO_", where FOO_ can be any
+string beginning with a letter and containing only uppercase
+and lowercase letters, digits, and the underscore (i.e., a C language
+identifier). This creates a set of macros in pnglibconf.h, so this is
+transparent to applications; their function calls get transformed by
+the macros to use the modified names.
+
+XII. Configuring for compiler xxx:
+
+All includes for libpng are in pngconf.h. If you need to add, change
+or delete an include, this is the place to do it.
+The includes that are not needed outside libpng are placed in pngpriv.h,
+which is only used by the routines inside libpng itself.
+The files in libpng proper only include pngpriv.h and png.h, which
+in turn includes pngconf.h and, as of libpng-1.5.0, pnglibconf.h.
+As of libpng-1.5.0, pngpriv.h also includes three other private header
+files, pngstruct.h, pnginfo.h, and pngdebug.h, which contain material
+that previously appeared in the public headers.
+
+XIII. Removing unwanted object code
+
+There are a bunch of #define's in pngconf.h that control what parts of
+libpng are compiled. All the defines end in _SUPPORTED. If you are
+never going to use a capability, you can change the #define to #undef
+before recompiling libpng and save yourself code and data space, or
+you can turn off individual capabilities with defines that begin with
+PNG_NO_.
+
+In libpng-1.5.0 and later, the #define's are in pnglibconf.h instead.
+
+You can also turn all of the transforms and ancillary chunk capabilities
+off en masse with compiler directives that define
+PNG_NO_READ[or WRITE]_TRANSFORMS, or PNG_NO_READ[or WRITE]_ANCILLARY_CHUNKS,
+or all four, along with directives to turn on any of the capabilities that
+you do want. The PNG_NO_READ[or WRITE]_TRANSFORMS directives disable the
+extra transformations but still leave the library fully capable of reading
+and writing PNG files with all known public chunks. Use of the
+PNG_NO_READ[or WRITE]_ANCILLARY_CHUNKS directive produces a library
+that is incapable of reading or writing ancillary chunks. If you are
+not using the progressive reading capability, you can turn that off
+with PNG_NO_PROGRESSIVE_READ (don't confuse this with the INTERLACING
+capability, which you'll still have).
+
+All the reading and writing specific code are in separate files, so the
+linker should only grab the files it needs. However, if you want to
+make sure, or if you are building a stand alone library, all the
+reading files start with "pngr" and all the writing files start with "pngw".
+The files that don't match either (like png.c, pngtrans.c, etc.)
+are used for both reading and writing, and always need to be included.
+The progressive reader is in pngpread.c
+
+If you are creating or distributing a dynamically linked library (a .so
+or DLL file), you should not remove or disable any parts of the library,
+as this will cause applications linked with different versions of the
+library to fail if they call functions not available in your library.
+The size of the library itself should not be an issue, because only
+those sections that are actually used will be loaded into memory.
+
+XIV. Changes to the build and configuration of libpng in libpng-1.5.x
+
+Details of internal changes to the library code can be found in the CHANGES
+file and in the GIT repository logs. These will be of no concern to the vast
+majority of library users or builders; however, the few who configure libpng
+to a non-default feature set may need to change how this is done.
+
+There should be no need for library builders to alter build scripts if
+these use the distributed build support - configure or the makefiles -
+however, users of the makefiles may care to update their build scripts
+to build pnglibconf.h where the corresponding makefile does not do so.
+
+Building libpng with a non-default configuration has changed completely.
+The old method using pngusr.h should still work correctly even though the
+way pngusr.h is used in the build has been changed; however, library
+builders will probably want to examine the changes to take advantage of
+new capabilities and to simplify their build system.
+
+A. Specific changes to library configuration capabilities
+
+The exact mechanism used to control attributes of API functions has
+changed. A single set of operating system independent macro definitions
+is used and operating system specific directives are defined in
+pnglibconf.h
+
+As part of this the mechanism used to choose procedure call standards on
+those systems that allow a choice has been changed. At present this only
+affects certain Microsoft (DOS, Windows) and IBM (OS/2) operating systems
+running on Intel processors. As before, PNGAPI is defined where required
+to control the exported API functions; however, two new macros, PNGCBAPI
+and PNGCAPI, are used instead for callback functions (PNGCBAPI) and
+(PNGCAPI) for functions that must match a C library prototype (currently
+only png_longjmp_ptr, which must match the C longjmp function.) The new
+approach is documented in pngconf.h
+
+Despite these changes, libpng 1.5.0 only supports the native C function
+calling standard on those platforms tested so far (__cdecl on Microsoft
+Windows). This is because the support requirements for alternative
+calling conventions seem to no longer exist. Developers who find it
+necessary to set PNG_API_RULE to 1 should advise the mailing list
+(png-mng-implement) of this and library builders who use Openwatcom and
+therefore set PNG_API_RULE to 2 should also contact the mailing list.
+
+B. Changes to the configuration mechanism
+
+Prior to libpng-1.5.0 library builders who needed to configure libpng
+had either to modify the exported pngconf.h header file to add system
+specific configuration or had to write feature selection macros into
+pngusr.h and cause this to be included into pngconf.h by defining
+PNG_USER_CONFIG. The latter mechanism had the disadvantage that an
+application built without PNG_USER_CONFIG defined would see the
+unmodified, default, libpng API and thus would probably fail to link.
+
+These mechanisms still work in the configure build and in any makefile
+build that builds pnglibconf.h, although the feature selection macros
+have changed somewhat as described above. In 1.5.0, however, pngusr.h is
+processed only once, at the time the exported header file pnglibconf.h is
+built. pngconf.h no longer includes pngusr.h; therefore, pngusr.h is ignored
+after the build of pnglibconf.h and it is never included in an application
+build.
+
+The formerly used alternative of adding a list of feature macros to the
+CPPFLAGS setting in the build also still works; however, the macros will be
+copied to pnglibconf.h and this may produce macro redefinition warnings
+when the individual C files are compiled.
+
+All configuration now only works if pnglibconf.h is built from
+scripts/pnglibconf.dfa. This requires the program awk. Brian Kernighan
+(the original author of awk) maintains C source code of that awk and this
+and all known later implementations (often called by subtly different
+names - nawk and gawk for example) are adequate to build pnglibconf.h.
+The Sun Microsystems (now Oracle) program 'awk' is an earlier version
+and does not work; this may also apply to other systems that have a
+functioning awk called 'nawk'.
+
+Configuration options are now documented in scripts/pnglibconf.dfa. This
+file also includes dependency information that ensures a configuration is
+consistent; that is, if a feature is switched off, dependent features are
+also switched off. As a recommended alternative to using feature macros in
+pngusr.h a system builder may also define equivalent options in pngusr.dfa
+(or, indeed, any file) and add that to the configuration by setting
+DFA_XTRA to the file name. The makefiles in contrib/pngminim illustrate
+how to do this, and also illustrate a case where pngusr.h is still required.
+
+After you have built libpng, the definitions that were recorded in
+pnglibconf.h are available to your application (pnglibconf.h is included
+in png.h and gets installed alongside png.h and pngconf.h in your
+$PREFIX/include directory). Do not edit pnglibconf.h after you have built
+libpng, because than the settings would not accurately reflect the settings
+that were used to build libpng.
+
+XV. Setjmp/longjmp issues
+
+Libpng uses setjmp()/longjmp() for error handling. Unfortunately setjmp()
+is known to be not thread-safe on some platforms and we don't know of
+any platform where it is guaranteed to be thread-safe. Therefore, if
+your application is going to be using multiple threads, you should
+configure libpng with PNG_NO_SETJMP in your pngusr.dfa file, with
+-DPNG_NO_SETJMP on your compile line, or with
+
+ #undef PNG_SETJMP_SUPPORTED
+
+in your pnglibconf.h or pngusr.h.
+
+Starting with libpng-1.6.0, the library included a "simplified API".
+This requires setjmp/longjmp, so you must either build the library
+with PNG_SETJMP_SUPPORTED defined, or with PNG_SIMPLIFIED_READ_SUPPORTED
+and PNG_SIMPLIFIED_WRITE_SUPPORTED undefined.
+
+XVI. Other sources of information about libpng:
+
+Further information can be found in the README and libpng-manual.txt
+files, in the individual makefiles, in png.h, and the manual pages
+libpng.3 and png.5.
+
+Using the ./configure script -- 16 December 2002.
+=================================================
+
+The ./configure script should work compatibly with what scripts/makefile.*
+did, however there are some options you might need to add to configure
+explicitly, which previously was done semi-automatically (if you didn't edit
+scripts/makefile.* yourself, that is)
+
+CFLAGS="-Wall -O -funroll-loops \
+-malign-loops=2 -malign-functions=2" ./configure --prefix=/usr/include \
+--with-pkgconfigdir=/usr/lib/pkgconfig --includedir=/usr/include
+
+You can alternatively specify --includedir=/usr/include, /usr/local/include,
+/usr/include/libpng16, or whatever.
+
+If you find that the configure script is out-of-date or is not supporting
+your platform properly, try running autogen.sh to regenerate "configure",
+"Makefile.in", and the other configuration files. Then try configure again.
+
diff --git a/libpng/LICENSE b/libpng/LICENSE
new file mode 100644
index 0000000..82dbe11
--- /dev/null
+++ b/libpng/LICENSE
@@ -0,0 +1,112 @@
+
+This copy of the libpng notices is provided for your convenience. In case of
+any discrepancy between this copy and the notices in the file png.h that is
+included in the libpng distribution, the latter shall prevail.
+
+COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
+
+If you modify libpng you may insert additional notices immediately following
+this sentence.
+
+This code is released under the libpng license.
+
+libpng versions 1.0.7, July 1, 2000, through 1.6.20, December 3, 2015, are
+Copyright (c) 2000-2002, 2004, 2006-2015 Glenn Randers-Pehrson, are
+derived from libpng-1.0.6, and are distributed according to the same
+disclaimer and license as libpng-1.0.6 with the following individuals
+added to the list of Contributing Authors:
+
+ Simon-Pierre Cadieux
+ Eric S. Raymond
+ Mans Rullgard
+ Cosmin Truta
+ Gilles Vollant
+ James Yu
+
+and with the following additions to the disclaimer:
+
+ There is no warranty against interference with your enjoyment of the
+ library or against infringement. There is no warranty that our
+ efforts or the library will fulfill any of your particular purposes
+ or needs. This library is provided with all faults, and the entire
+ risk of satisfactory quality, performance, accuracy, and effort is with
+ the user.
+
+libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
+Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from
+libpng-0.96, and are distributed according to the same disclaimer and
+license as libpng-0.96, with the following individuals added to the list
+of Contributing Authors:
+
+ Tom Lane
+ Glenn Randers-Pehrson
+ Willem van Schaik
+
+libpng versions 0.89, June 1996, through 0.96, May 1997, are
+Copyright (c) 1996-1997 Andreas Dilger, are derived from libpng-0.88,
+and are distributed according to the same disclaimer and license as
+libpng-0.88, with the following individuals added to the list of
+Contributing Authors:
+
+ John Bowler
+ Kevin Bracey
+ Sam Bushell
+ Magnus Holmgren
+ Greg Roelofs
+ Tom Tanner
+
+libpng versions 0.5, May 1995, through 0.88, January 1996, are
+Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
+
+For the purposes of this copyright and license, "Contributing Authors"
+is defined as the following set of individuals:
+
+ Andreas Dilger
+ Dave Martindale
+ Guy Eric Schalnat
+ Paul Schmidt
+ Tim Wegner
+
+The PNG Reference Library is supplied "AS IS". The Contributing Authors
+and Group 42, Inc. disclaim all warranties, expressed or implied,
+including, without limitation, the warranties of merchantability and of
+fitness for any purpose. The Contributing Authors and Group 42, Inc.
+assume no liability for direct, indirect, incidental, special, exemplary,
+or consequential damages, which may result from the use of the PNG
+Reference Library, even if advised of the possibility of such damage.
+
+Permission is hereby granted to use, copy, modify, and distribute this
+source code, or portions hereof, for any purpose, without fee, subject
+to the following restrictions:
+
+ 1. The origin of this source code must not be misrepresented.
+
+ 2. Altered versions must be plainly marked as such and must not
+ be misrepresented as being the original source.
+
+ 3. This Copyright notice may not be removed or altered from any
+ source or altered source distribution.
+
+The Contributing Authors and Group 42, Inc. specifically permit, without
+fee, and encourage the use of this source code as a component to
+supporting the PNG file format in commercial products. If you use this
+source code in a product, acknowledgment is not required but would be
+appreciated.
+
+END OF COPYRIGHT NOTICE, DISCLAIMER, and LICENSE.
+
+A "png_get_copyright" function is available, for convenient use in "about"
+boxes and the like:
+
+ printf("%s", png_get_copyright(NULL));
+
+Also, the PNG logo (in PNG format, of course) is supplied in the
+files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
+
+Libpng is OSI Certified Open Source Software. OSI Certified Open Source is
+a certification mark of the Open Source Initiative. OSI has not addressed
+the additional disclaimers inserted at version 1.0.7.
+
+Glenn Randers-Pehrson
+glennrp at users.sourceforge.net
+December 3, 2015
diff --git a/libpng/MODULE_LICENSE_BSD_LIKE b/libpng/MODULE_LICENSE_BSD_LIKE
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/libpng/MODULE_LICENSE_BSD_LIKE
diff --git a/libpng/Makefile.am b/libpng/Makefile.am
new file mode 100644
index 0000000..73097db
--- /dev/null
+++ b/libpng/Makefile.am
@@ -0,0 +1,361 @@
+# Makefile.am:
+# Source file for Makefile.in (and hence Makefile)
+#
+
+PNGLIB_BASENAME= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@
+
+ACLOCAL_AMFLAGS = -I scripts
+
+# test programs - run on make check, make distcheck
+check_PROGRAMS= pngtest pngunknown pngstest pngvalid pngimage
+
+# Utilities - installed
+bin_PROGRAMS= pngfix png-fix-itxt
+
+# This ensures that pnglibconf.h gets built at the start of 'make all' or
+# 'make check', but it does not add dependencies to the individual programs,
+# this is done below.
+#
+# IMPORTANT: always add the object modules of new programs to the list below
+# because otherwise the sequence 'configure; make new-program' will *sometimes*
+# result in the installed (system) pnglibconf.h being used and the result is
+# always wrong and always very confusing.
+BUILT_SOURCES = pnglibconf.h
+
+pngtest_SOURCES = pngtest.c
+pngtest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+
+pngvalid_SOURCES = contrib/libtests/pngvalid.c
+pngvalid_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+
+pngstest_SOURCES = contrib/libtests/pngstest.c
+pngstest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+
+pngunknown_SOURCES = contrib/libtests/pngunknown.c
+pngunknown_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+
+pngimage_SOURCES = contrib/libtests/pngimage.c
+pngimage_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+
+pngfix_SOURCES = contrib/tools/pngfix.c
+pngfix_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+
+png_fix_itxt_SOURCES = contrib/tools/png-fix-itxt.c
+
+# Generally these are single line shell scripts to run a test with a particular
+# set of parameters:
+TESTS =\
+ tests/pngtest\
+ tests/pngvalid-gamma-16-to-8 tests/pngvalid-gamma-alpha-mode\
+ tests/pngvalid-gamma-background tests/pngvalid-gamma-expand16-alpha-mode\
+ tests/pngvalid-gamma-expand16-background\
+ tests/pngvalid-gamma-expand16-transform tests/pngvalid-gamma-sbit\
+ tests/pngvalid-gamma-threshold tests/pngvalid-gamma-transform\
+ tests/pngvalid-progressive-size\
+ tests/pngvalid-progressive-interlace-standard\
+ tests/pngvalid-transform\
+ tests/pngvalid-progressive-standard tests/pngvalid-standard\
+ tests/pngstest-1.8 tests/pngstest-1.8-alpha tests/pngstest-linear\
+ tests/pngstest-linear-alpha tests/pngstest-none tests/pngstest-none-alpha\
+ tests/pngstest-sRGB tests/pngstest-sRGB-alpha tests/pngunknown-IDAT\
+ tests/pngunknown-discard tests/pngunknown-if-safe tests/pngunknown-sAPI\
+ tests/pngunknown-sTER tests/pngunknown-save tests/pngunknown-vpAg\
+ tests/pngimage-quick tests/pngimage-full
+
+# man pages
+dist_man_MANS= libpng.3 libpngpf.3 png.5
+
+# generate the -config scripts if required
+binconfigs= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@-config
+EXTRA_SCRIPTS= libpng-config libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@-config
+bin_SCRIPTS= @binconfigs@
+
+# rules to build libpng, only build the old library on request
+lib_LTLIBRARIES=libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+# EXTRA_LTLIBRARIES= libpng.la
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = png.c pngerror.c\
+ pngget.c pngmem.c pngpread.c pngread.c pngrio.c pngrtran.c pngrutil.c\
+ pngset.c pngtrans.c pngwio.c pngwrite.c pngwtran.c pngwutil.c\
+ png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h pngusr.dfa
+
+if PNG_ARM_NEON
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += arm/arm_init.c\
+ arm/filter_neon.S arm/filter_neon_intrinsics.c
+endif
+
+nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = pnglibconf.h
+
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS = -no-undefined -export-dynamic \
+ -version-number @PNGLIB_MAJOR@@PNGLIB_MINOR@:@PNGLIB_RELEASE@:0
+
+if HAVE_LD_VERSION_SCRIPT
+# Versioned symbols and restricted exports
+if HAVE_SOLARIS_LD
+ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS += -Wl,-M -Wl,libpng.vers
+else
+ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS += -Wl,--version-script=libpng.vers
+endif
+
+ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES = libpng.vers
+else
+# Only restricted exports when possible
+ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS += -export-symbols libpng.sym
+ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES = libpng.sym
+endif
+
+#distribute headers in /usr/include/libpng/*
+pkgincludedir= $(includedir)/$(PNGLIB_BASENAME)
+pkginclude_HEADERS= png.h pngconf.h
+nodist_pkginclude_HEADERS= pnglibconf.h
+
+# pkg-config stuff, note that libpng.pc is always required in order
+# to get the correct library
+pkgconfigdir = @pkgconfigdir@
+pkgconfig_DATA = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.pc
+
+# Extra source distribution files, '${srcdir}' is used below to stop build files
+# from those directories being included. This only works if the configure is
+# not done in the source directory!
+EXTRA_DIST= \
+ ANNOUNCE CHANGES INSTALL LICENSE README TODO \
+ pngtest.png pngbar.png pngnow.png pngbar.jpg autogen.sh \
+ ${srcdir}/contrib ${srcdir}/projects ${srcdir}/scripts \
+ $(TESTS) $(XFAIL_TESTS) tests/pngstest \
+ CMakeLists.txt example.c libpng-manual.txt
+
+SCRIPT_CLEANFILES=scripts/*.out scripts/*.chk
+
+CLEANFILES= *.tf? pngout.png libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.pc \
+ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@-config libpng.vers libpng.sym \
+ check.new pnglibconf.h pngprefix.h symbols.new pngtest-log.txt \
+ pnglibconf.out pnglibconf.c pnglibconf.pre pnglibconf.dfn \
+ $(SCRIPT_CLEANFILES)
+
+MAINTAINERCLEANFILES = Makefile.in aclocal.m4 config.guess config.h.in \
+config.sub configure depcomp install-sh ltmain.sh missing
+
+# PNG_COPTS give extra options for the C compiler to be used on all compilation
+# steps (unless targe_CFLAGS is specified; that will take precedence over
+# AM_CFLAGS)
+PNG_COPTS = @PNG_COPTS@
+AM_CFLAGS = ${PNG_COPTS}
+
+# DFNCPP is normally just CPP - the C preprocessor - but on Solaris and maybe
+# other operating systems (NeXT?) the C preprocessor selected by configure
+# checks input tokens for validity - effectively it performs part of the ANSI-C
+# parsing - and therefore fails with the .df files. configure.ac has special
+# checks for this and sets DFNCPP appropriately.
+DFNCPP = @DFNCPP@
+
+SUFFIXES = .chk .out
+
+$(PNGLIB_BASENAME).pc: libpng.pc
+ cp libpng.pc $@
+
+$(PNGLIB_BASENAME)-config: libpng-config
+ cp libpng-config $@
+
+scripts/sym.out scripts/vers.out: png.h pngconf.h pnglibconf.h
+scripts/prefix.out: png.h pngconf.h pnglibconf.out
+scripts/symbols.out: png.h pngconf.h $(srcdir)/scripts/pnglibconf.h.prebuilt
+scripts/intprefix.out: pnglibconf.h
+
+libpng.sym: scripts/sym.out
+ rm -f $@
+ cp $? $@
+libpng.vers: scripts/vers.out
+ rm -f $@
+ cp $? $@
+
+if DO_PNG_PREFIX
+# Rename functions in scripts/prefix.out with a PNG_PREFIX prefix.
+# Rename macros in scripts/macro.lst from PNG_PREFIXpng_ to PNG_ (the actual
+# implementation of the macro).
+pnglibconf.h: pnglibconf.out scripts/prefix.out scripts/macro.lst
+ rm -f $@
+ $(AWK) 's==0 && NR>1{print prev}\
+ s==0{prev=$$0}\
+ s==1{print "#define", $$1, "@PNG_PREFIX@" $$1}\
+ s==2{print "#define @PNG_PREFIX@png_" $$1, "PNG_" $$1}\
+ END{print prev}' s=0 pnglibconf.out s=1 scripts/prefix.out\
+ s=2 ${srcdir}/scripts/macro.lst >pnglibconf.tf8
+ mv pnglibconf.tf8 $@
+
+pngprefix.h: scripts/intprefix.out
+ rm -f pngprefix.tf1
+ $(AWK) '{print "#define", $$1, "@PNG_PREFIX@" $$1}' $? >pngprefix.tf1
+ mv pngprefix.tf1 $@
+else
+pnglibconf.h: pnglibconf.out
+ rm -f $@
+ cp $? $@
+
+pngprefix.h: # is empty
+ :>$@
+endif
+
+$(srcdir)/scripts/pnglibconf.h.prebuilt:
+ @echo "Attempting to build $@" >&2
+ @echo "This is a machine generated file, but if you want to make" >&2
+ @echo "a new one simply make 'scripts/pnglibconf.out', copy that" >&2
+ @echo "AND set PNG_ZLIB_VERNUM to 0 (you MUST do this)" >&2
+ @exit 1
+
+# The following is necessary to ensure that the local pnglibconf.h is used, not
+# an installed one (this can happen immediately after on a clean system if
+# 'make test' is the first thing the user does.) Only files which include
+# one of the png source files (typically png.h or pngpriv.h) need to be listed
+# here:
+pngtest.o: pnglibconf.h
+
+contrib/libtests/makepng.o: pnglibconf.h
+contrib/libtests/pngstest.o: pnglibconf.h
+contrib/libtests/pngunknown.o: pnglibconf.h
+contrib/libtests/pngimage.o: pnglibconf.h
+contrib/libtests/pngvalid.o: pnglibconf.h
+contrib/libtests/readpng.o: pnglibconf.h
+contrib/libtests/tarith.o: pnglibconf.h
+contrib/libtests/timepng.o: pnglibconf.h
+
+contrib/tools/makesRGB.o: pnglibconf.h
+contrib/tools/pngfix.o: pnglibconf.h
+
+# We must use -DPNG_NO_USE_READ_MACROS here even when the library may actually
+# be built with PNG_USE_READ_MACROS; this prevents the read macros from
+# interfering with the symbol file format.
+SYMBOL_CFLAGS = -DPNGLIB_LIBNAME='PNG@PNGLIB_MAJOR@@PNGLIB_MINOR@_0'\
+ -DPNGLIB_VERSION='@PNGLIB_VERSION@'\
+ -DSYMBOL_PREFIX='$(SYMBOL_PREFIX)'\
+ -DPNG_NO_USE_READ_MACROS -DPNG_BUILDING_SYMBOL_TABLE
+
+if DO_PNG_PREFIX
+SYMBOL_CFLAGS += -DPNG_PREFIX='@PNG_PREFIX@'
+endif
+
+.c.out:
+ rm -f $@ $*.tf[12]
+ test -d scripts || mkdir scripts || test -d scripts
+ $(DFNCPP) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES)\
+ $(CPPFLAGS) $(SYMBOL_CFLAGS) $< > $*.tf1
+ $(AWK) -f "${srcdir}/scripts/dfn.awk" out="$*.tf2" $*.tf1 1>&2
+ rm -f $*.tf1
+ mv $*.tf2 $@
+
+# The .c file for pnglibconf.h is machine generated
+pnglibconf.c: scripts/pnglibconf.dfa scripts/options.awk pngconf.h pngusr.dfa $(DFA_XTRA)
+ rm -f $@ $*.tf[45]
+ $(AWK) -f ${srcdir}/scripts/options.awk out=$*.tf4 version=search\
+ ${srcdir}/pngconf.h ${srcdir}/scripts/pnglibconf.dfa\
+ ${srcdir}/pngusr.dfa $(DFA_XTRA) 1>&2
+ $(AWK) -f ${srcdir}/scripts/options.awk out=$*.tf5 $*.tf4 1>&2
+ rm $*.tf4
+ mv $*.tf5 $@
+
+# Symbol checks (.def and .out files should match)
+scripts/symbols.chk: scripts/checksym.awk scripts/symbols.def scripts/symbols.out
+
+.out.chk:
+ rm -f $@ $*.new
+ $(AWK) -f ${srcdir}/scripts/checksym.awk ${srcdir}/scripts/${*F}.def\
+ of="$*.new" $< >&2
+ mv $*.new $@
+
+# used on demand to regenerate the standard header, CPPFLAGS should
+# be empty - no non-standard defines
+scripts/pnglibconf.c: scripts/pnglibconf.dfa scripts/options.awk pngconf.h
+ rm -f $@ pnglibconf.tf[67]
+ test -z "$(CPPFLAGS)"
+ echo "com @PNGLIB_VERSION@ STANDARD API DEFINITION" |\
+ $(AWK) -f ${srcdir}/scripts/options.awk out=pnglibconf.tf6\
+ logunsupported=1 version=search ${srcdir}/pngconf.h -\
+ ${srcdir}/scripts/pnglibconf.dfa 1>&2
+ $(AWK) -f ${srcdir}/scripts/options.awk out=pnglibconf.tf7\
+ pnglibconf.tf6 1>&2
+ rm pnglibconf.tf6
+ mv pnglibconf.tf7 $@
+
+$(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS): png.h pngconf.h \
+ pnglibconf.h pngpriv.h pngdebug.h pnginfo.h pngstruct.h pngprefix.h
+
+test: check-am
+
+# Extra checks
+check: scripts/symbols.chk
+
+# Don't distribute the generated script files
+dist-hook:
+ cd '$(top_distdir)'; rm -f $(SCRIPT_CLEANFILES)
+
+# Make links between installed files with release-specific names and the generic
+# file names. If this install rule is run the generic names will be deleted and
+# recreated - this has obvious issues for systems with multiple installations.
+
+install-header-links:
+ @set -ex; cd '$(DESTDIR)$(includedir)'; for f in $(HEADERS); do \
+ rm -f "$$f"; $(LN_S) "$(PNGLIB_BASENAME)/$$f" "$$f"; done
+
+uninstall-header-links:
+ cd '$(DESTDIR)$(includedir)'; rm -f $(HEADERS)
+
+install-libpng-pc:
+ @set -ex; cd '$(DESTDIR)$(pkgconfigdir)'; rm -f libpng.pc; \
+ $(LN_S) '$(PNGLIB_BASENAME).pc' libpng.pc
+
+uninstall-libpng-pc:
+ rm -f '$(DESTDIR)$(pkgconfigdir)/libpng.pc'
+
+# EXT_LIST is a list of the possibly library directory extensions, this exists
+# because we can't find a good way of discovering the file extensions that are
+# actually installed on a given system, so instead we check for every extension
+# we have seen.
+
+EXT_LIST = a dll.a so so.@PNGLIB_MAJOR@@PNGLIB_MINOR@.@PNGLIB_RELEASE@ la sl dylib
+
+install-library-links:
+ @set -x; cd '$(DESTDIR)$(libdir)';\
+ for ext in $(EXT_LIST); do\
+ rm -f "libpng.$$ext";\
+ if test -f "$(PNGLIB_BASENAME).$$ext"; then\
+ $(LN_S) "$(PNGLIB_BASENAME).$$ext" "libpng.$$ext" || exit 1;\
+ fi;\
+ done
+
+uninstall-library-links:
+ @set -x; cd '$(DESTDIR)$(libdir)'; for ext in $(EXT_LIST); do\
+ rm -f "libpng.$$ext"; done
+
+install-libpng-config:
+ @set -ex; cd '$(DESTDIR)$(bindir)'; rm -f libpng-config; \
+ $(LN_S) '$(PNGLIB_BASENAME)-config' libpng-config
+
+uninstall-libpng-config:
+ rm -f '$(DESTDIR)$(bindir)/libpng-config'
+
+if DO_INSTALL_LINKS
+# If --enable-unversioned-links is specified the header and lib file links
+# will be automatically made on a 'make install':
+
+install-data-hook: install-header-links
+uninstall-hook: uninstall-header-links
+install-exec-hook: install-library-links
+uninstall-hook: uninstall-library-links
+endif
+
+if DO_INSTALL_LIBPNG_PC
+# Likewise, --install-pc causes libpng.pc to be constructed:
+
+install-data-hook: install-libpng-pc
+uninstall-hook: uninstall-libpng-pc
+endif
+
+if DO_INSTALL_LIBPNG_CONFIG
+# And --install-config:
+
+install-exec-hook: install-libpng-config
+uninstall-hook: uninstall-libpng-config
+endif
+
+# The following addition ensures that 'make all' always builds the test programs
+# too. It used to, but some change either in libpng or configure stopped this
+# working.
+all-am: $(check_PROGRAMS)
diff --git a/libpng/NOTICE b/libpng/NOTICE
new file mode 100644
index 0000000..11f6ffe
--- /dev/null
+++ b/libpng/NOTICE
@@ -0,0 +1,112 @@
+
+This copy of the libpng notices is provided for your convenience. In case of
+any discrepancy between this copy and the notices in the file png.h that is
+included in the libpng distribution, the latter shall prevail.
+
+COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
+
+If you modify libpng you may insert additional notices immediately following
+this sentence.
+
+This code is released under the libpng license.
+
+libpng versions 1.0.7, July 1, 2000, through 1.6.19, November 12, 2015, are
+Copyright (c) 2000-2002, 2004, 2006-2015 Glenn Randers-Pehrson, are
+derived from libpng-1.0.6, and are distributed according to the same
+disclaimer and license as libpng-1.0.6 with the following individuals
+added to the list of Contributing Authors:
+
+ Simon-Pierre Cadieux
+ Eric S. Raymond
+ Mans Rullgard
+ Cosmin Truta
+ Gilles Vollant
+ James Yu
+
+and with the following additions to the disclaimer:
+
+ There is no warranty against interference with your enjoyment of the
+ library or against infringement. There is no warranty that our
+ efforts or the library will fulfill any of your particular purposes
+ or needs. This library is provided with all faults, and the entire
+ risk of satisfactory quality, performance, accuracy, and effort is with
+ the user.
+
+libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
+Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from
+libpng-0.96, and are distributed according to the same disclaimer and
+license as libpng-0.96, with the following individuals added to the list
+of Contributing Authors:
+
+ Tom Lane
+ Glenn Randers-Pehrson
+ Willem van Schaik
+
+libpng versions 0.89, June 1996, through 0.96, May 1997, are
+Copyright (c) 1996-1997 Andreas Dilger, are derived from libpng-0.88,
+and are distributed according to the same disclaimer and license as
+libpng-0.88, with the following individuals added to the list of
+Contributing Authors:
+
+ John Bowler
+ Kevin Bracey
+ Sam Bushell
+ Magnus Holmgren
+ Greg Roelofs
+ Tom Tanner
+
+libpng versions 0.5, May 1995, through 0.88, January 1996, are
+Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
+
+For the purposes of this copyright and license, "Contributing Authors"
+is defined as the following set of individuals:
+
+ Andreas Dilger
+ Dave Martindale
+ Guy Eric Schalnat
+ Paul Schmidt
+ Tim Wegner
+
+The PNG Reference Library is supplied "AS IS". The Contributing Authors
+and Group 42, Inc. disclaim all warranties, expressed or implied,
+including, without limitation, the warranties of merchantability and of
+fitness for any purpose. The Contributing Authors and Group 42, Inc.
+assume no liability for direct, indirect, incidental, special, exemplary,
+or consequential damages, which may result from the use of the PNG
+Reference Library, even if advised of the possibility of such damage.
+
+Permission is hereby granted to use, copy, modify, and distribute this
+source code, or portions hereof, for any purpose, without fee, subject
+to the following restrictions:
+
+ 1. The origin of this source code must not be misrepresented.
+
+ 2. Altered versions must be plainly marked as such and must not
+ be misrepresented as being the original source.
+
+ 3. This Copyright notice may not be removed or altered from any
+ source or altered source distribution.
+
+The Contributing Authors and Group 42, Inc. specifically permit, without
+fee, and encourage the use of this source code as a component to
+supporting the PNG file format in commercial products. If you use this
+source code in a product, acknowledgment is not required but would be
+appreciated.
+
+END OF COPYRIGHT NOTICE, DISCLAIMER, and LICENSE.
+
+A "png_get_copyright" function is available, for convenient use in "about"
+boxes and the like:
+
+ printf("%s", png_get_copyright(NULL));
+
+Also, the PNG logo (in PNG format, of course) is supplied in the
+files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
+
+Libpng is OSI Certified Open Source Software. OSI Certified Open Source is
+a certification mark of the Open Source Initiative. OSI has not addressed
+the additional disclaimers inserted at version 1.0.7.
+
+Glenn Randers-Pehrson
+glennrp at users.sourceforge.net
+November 12, 2015
diff --git a/libpng/README b/libpng/README
new file mode 100644
index 0000000..59f1f91
--- /dev/null
+++ b/libpng/README
@@ -0,0 +1,215 @@
+README for libpng version 1.6.20 - December 3, 2015 (shared library 16.0)
+See the note about version numbers near the top of png.h
+
+See INSTALL for instructions on how to install libpng.
+
+Libpng comes in several distribution formats. Get libpng-*.tar.gz or
+libpng-*.tar.xz or if you want UNIX-style line endings in the text files,
+or lpng*.7z or lpng*.zip if you want DOS-style line endings.
+
+Version 0.89 was the first official release of libpng. Don't let the
+fact that it's the first release fool you. The libpng library has been in
+extensive use and testing since mid-1995. By late 1997 it had
+finally gotten to the stage where there hadn't been significant
+changes to the API in some time, and people have a bad feeling about
+libraries with versions < 1.0. Version 1.0.0 was released in
+March 1998.
+
+****
+Note that some of the changes to the png_info structure render this
+version of the library binary incompatible with libpng-0.89 or
+earlier versions if you are using a shared library. The type of the
+"filler" parameter for png_set_filler() has changed from png_byte to
+png_uint_32, which will affect shared-library applications that use
+this function.
+
+To avoid problems with changes to the internals of png info_struct,
+new APIs have been made available in 0.95 to avoid direct application
+access to info_ptr. These functions are the png_set_<chunk> and
+png_get_<chunk> functions. These functions should be used when
+accessing/storing the info_struct data, rather than manipulating it
+directly, to avoid such problems in the future.
+
+It is important to note that the APIs did not make current programs
+that access the info struct directly incompatible with the new
+library, through libpng-1.2.x. In libpng-1.4.x, which was meant to
+be a transitional release, members of the png_struct and the
+info_struct can still be accessed, but the compiler will issue a
+warning about deprecated usage. Since libpng-1.5.0, direct access
+to these structs is not allowed, and the definitions of the structs
+reside in private pngstruct.h and pnginfo.h header files that are not
+accessible to applications. It is strongly suggested that new
+programs use the new APIs (as shown in example.c and pngtest.c), and
+older programs be converted to the new format, to facilitate upgrades
+in the future.
+****
+
+Additions since 0.90 include the ability to compile libpng as a
+Windows DLL, and new APIs for accessing data in the info struct.
+Experimental functions include the ability to set weighting and cost
+factors for row filter selection, direct reads of integers from buffers
+on big-endian processors that support misaligned data access, faster
+methods of doing alpha composition, and more accurate 16->8 bit color
+conversion.
+
+The additions since 0.89 include the ability to read from a PNG stream
+which has had some (or all) of the signature bytes read by the calling
+application. This also allows the reading of embedded PNG streams that
+do not have the PNG file signature. As well, it is now possible to set
+the library action on the detection of chunk CRC errors. It is possible
+to set different actions based on whether the CRC error occurred in a
+critical or an ancillary chunk.
+
+The changes made to the library, and bugs fixed are based on discussions
+on the PNG-implement mailing list and not on material submitted
+privately to Guy, Andreas, or Glenn. They will forward any good
+suggestions to the list.
+
+For a detailed description on using libpng, read libpng-manual.txt. For
+examples of libpng in a program, see example.c and pngtest.c. For usage
+information and restrictions (what little they are) on libpng, see
+png.h. For a description on using zlib (the compression library used by
+libpng) and zlib's restrictions, see zlib.h
+
+I have included a general makefile, as well as several machine and
+compiler specific ones, but you may have to modify one for your own needs.
+
+You should use zlib 1.0.4 or later to run this, but it MAY work with
+versions as old as zlib 0.95. Even so, there are bugs in older zlib
+versions which can cause the output of invalid compression streams for
+some images. You will definitely need zlib 1.0.4 or later if you are
+taking advantage of the MS-DOS "far" structure allocation for the small
+and medium memory models. You should also note that zlib is a
+compression library that is useful for more things than just PNG files.
+You can use zlib as a drop-in replacement for fread() and fwrite() if
+you are so inclined.
+
+zlib should be available at the same place that libpng is, or at zlib.net.
+
+You may also want a copy of the PNG specification. It is available
+as an RFC, a W3C Recommendation, and an ISO/IEC Standard. You can find
+these at http://www.libpng.org/pub/png/documents/
+
+This code is currently being archived at libpng.sf.net in the
+[DOWNLOAD] area, and at ftp://ftp.simplesystems.org. If you can't find it
+in any of those places, e-mail me, and I'll help you find it.
+
+I am not a lawyer, but I believe that the Export Control Classification
+Number (ECCN) for libpng is EAR99, which means not subject to export
+controls or International Traffic in Arms Regulations (ITAR) because it
+is open source, publicly available software, that does not contain any
+encryption software. See the EAR, paragraphs 734.3(b)(3) and 734.7(b).
+
+If you have any code changes, requests, problems, etc., please e-mail
+them to me. Also, I'd appreciate any make files or project files,
+and any modifications you needed to make to get libpng to compile,
+along with a #define variable to tell what compiler/system you are on.
+If you needed to add transformations to libpng, or wish libpng would
+provide the image in a different way, drop me a note (and code, if
+possible), so I can consider supporting the transformation.
+Finally, if you get any warning messages when compiling libpng
+(note: not zlib), and they are easy to fix, I'd appreciate the
+fix. Please mention "libpng" somewhere in the subject line. Thanks.
+
+This release was created and will be supported by myself (of course
+based in a large way on Guy's and Andreas' earlier work), and the PNG
+development group.
+
+Send comments/corrections/commendations to png-mng-implement at
+lists.sourceforge.net (subscription required; visit
+https://lists.sourceforge.net/lists/listinfo/png-mng-implement
+to subscribe) or to glennrp at users.sourceforge.net
+
+You can't reach Guy, the original libpng author, at the addresses
+given in previous versions of this document. He and Andreas will
+read mail addressed to the png-implement list, however.
+
+Please do not send general questions about PNG. Send them to
+png-mng-misc at lists.sf.net (subscription required; visit
+https://lists.sourceforge.net/lists/listinfo/png-mng-misc to
+subscribe). If you have a question about something
+in the PNG specification that is related to using libpng, send it
+to me. Send me any questions that start with "I was using libpng,
+and ...". If in doubt, send questions to me. I'll bounce them
+to others, if necessary.
+
+Please do not send suggestions on how to change PNG. We have
+been discussing PNG for twenty years now, and it is official and
+finished. If you have suggestions for libpng, however, I'll
+gladly listen. Even if your suggestion is not used immediately,
+it may be used later.
+
+Files in this distribution:
+
+ ANNOUNCE => Announcement of this version, with recent changes
+ CHANGES => Description of changes between libpng versions
+ KNOWNBUG => List of known bugs and deficiencies
+ LICENSE => License to use and redistribute libpng
+ README => This file
+ TODO => Things not implemented in the current library
+ Y2KINFO => Statement of Y2K compliance
+ example.c => Example code for using libpng functions
+ libpng.3 => manual page for libpng (includes libpng-manual.txt)
+ libpng-manual.txt => Description of libpng and its functions
+ libpngpf.3 => manual page for libpng's private functions
+ png.5 => manual page for the PNG format
+ png.c => Basic interface functions common to library
+ png.h => Library function and interface declarations (public)
+ pngpriv.h => Library function and interface declarations (private)
+ pngconf.h => System specific library configuration (public)
+ pngstruct.h => png_struct declaration (private)
+ pnginfo.h => png_info struct declaration (private)
+ pngdebug.h => debugging macros (private)
+ pngerror.c => Error/warning message I/O functions
+ pngget.c => Functions for retrieving info from struct
+ pngmem.c => Memory handling functions
+ pngbar.png => PNG logo, 88x31
+ pngnow.png => PNG logo, 98x31
+ pngpread.c => Progressive reading functions
+ pngread.c => Read data/helper high-level functions
+ pngrio.c => Lowest-level data read I/O functions
+ pngrtran.c => Read data transformation functions
+ pngrutil.c => Read data utility functions
+ pngset.c => Functions for storing data into the info_struct
+ pngtest.c => Library test program
+ pngtest.png => Library test sample image
+ pngtrans.c => Common data transformation functions
+ pngwio.c => Lowest-level write I/O functions
+ pngwrite.c => High-level write functions
+ pngwtran.c => Write data transformations
+ pngwutil.c => Write utility functions
+ arm => Contains optimized code for the ARM platform
+ contrib => Contributions
+ examples => Example programs
+ gregbook => source code for PNG reading and writing, from
+ Greg Roelofs' "PNG: The Definitive Guide",
+ O'Reilly, 1999
+ libtests => Test programs
+ pngminim => Minimal decoder, encoder, and progressive decoder
+ programs demonstrating use of pngusr.dfa
+ pngminus => Simple pnm2png and png2pnm programs
+ pngsuite => Test images
+ tools => Various tools
+ visupng => Contains a MSVC workspace for VisualPng
+ projects => Contains project files and workspaces for
+ building a DLL
+ owatcom => Contains a WATCOM project for building libpng
+ visualc71 => Contains a Microsoft Visual C++ (MSVC)
+ workspace for building libpng and zlib
+ vstudio => Contains a Microsoft Visual C++ (MSVC)
+ workspace for building libpng and zlib
+ scripts => Directory containing scripts for building libpng:
+ (see scripts/README.txt for the list of scripts)
+
+Good luck, and happy coding.
+
+-Glenn Randers-Pehrson (current maintainer, since 1998)
+ Internet: glennrp at users.sourceforge.net
+
+-Andreas Eric Dilger (former maintainer, 1996-1997)
+ Internet: adilger at enel.ucalgary.ca
+ Web: http://www-mddsp.enel.ucalgary.ca/People/adilger/
+
+-Guy Eric Schalnat (original author and former maintainer, 1995-1996)
+ (formerly of Group 42, Inc)
+ Internet: gschal at infinet.com
diff --git a/libpng/README.android b/libpng/README.android
new file mode 100644
index 0000000..b582ca5
--- /dev/null
+++ b/libpng/README.android
@@ -0,0 +1,19 @@
+Any Android specific modifications to upstream libpng (1.6.20) should
+be listed here:
+
+(1) Android has added the following files.
+ pngusr.h
+ Android.mk
+ CleanSpec.mk
+ MODULE_LICENSE_BSD_LIKE
+ README.version
+
+(2) pnglibconf.h
+ This is copied from scripts/pnglibconf.h.prebuilt.
+ Android has undefined PNG_WARNINGS_SUPPORTED.
+
+(3) Removed contrib/testpngs/
+ There is no reason to check in all of these files if we won't
+ be using them.
+
+(4) PNG_INDEX_SUPPORTED optimizations.
diff --git a/libpng/README.version b/libpng/README.version
new file mode 100644
index 0000000..58890dd
--- /dev/null
+++ b/libpng/README.version
@@ -0,0 +1,3 @@
+URL: http://prdownloads.sourceforge.net/libpng/libpng-1.6.20.tar.gz?download
+Version: 1.6.20
+BugComponent: 87896
diff --git a/libpng/TODO b/libpng/TODO
new file mode 100644
index 0000000..7263377
--- /dev/null
+++ b/libpng/TODO
@@ -0,0 +1,29 @@
+/*
+TODO - list of things to do for libpng:
+
+Final bug fixes.
+Better C++ wrapper/full C++ implementation?
+Fix problem with C++ and EXTERN "C".
+cHRM transformation.
+Remove setjmp/longjmp usage in favor of returning error codes.
+Palette creation.
+Add "grayscale->palette" transformation and "palette->grayscale" detection.
+Improved dithering.
+Multi-lingual error and warning message support.
+Complete sRGB transformation (presently it simply uses gamma=0.45455).
+Make profile checking optional via a png_set_something() call.
+Man pages for function calls.
+Better documentation.
+Better filter selection
+ (counting huffman bits/precompression? filter inertia? filter costs?).
+Histogram creation.
+Text conversion between different code pages (Latin-1 -> Mac and DOS).
+Avoid building gamma tables whenever possible.
+Use greater precision when changing to linear gamma for compositing against
+ background and doing rgb-to-gray transformation.
+Investigate pre-incremented loop counters and other loop constructions.
+Add interpolated method of handling interlacing.
+Switch to the simpler zlib (zlib/libpng) license if legally possible.
+Extend pngvalid.c to validate more of the libpng transformations.
+
+*/
diff --git a/libpng/arm/arm_init.c b/libpng/arm/arm_init.c
new file mode 100644
index 0000000..fb3d50d
--- /dev/null
+++ b/libpng/arm/arm_init.c
@@ -0,0 +1,134 @@
+
+/* arm_init.c - NEON optimised filter functions
+ *
+ * Copyright (c) 2014 Glenn Randers-Pehrson
+ * Written by Mans Rullgard, 2011.
+ * Last changed in libpng 1.6.16 [December 22, 2014]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+/* Below, after checking __linux__, various non-C90 POSIX 1003.1 functions are
+ * called.
+ */
+#define _POSIX_SOURCE 1
+
+#include "../pngpriv.h"
+
+#ifdef PNG_READ_SUPPORTED
+
+#if PNG_ARM_NEON_OPT > 0
+#ifdef PNG_ARM_NEON_CHECK_SUPPORTED /* Do run-time checks */
+/* WARNING: it is strongly recommended that you do not build libpng with
+ * run-time checks for CPU features if at all possible. In the case of the ARM
+ * NEON instructions there is no processor-specific way of detecting the
+ * presence of the required support, therefore run-time detection is extremely
+ * OS specific.
+ *
+ * You may set the macro PNG_ARM_NEON_FILE to the file name of file containing
+ * a fragment of C source code which defines the png_have_neon function. There
+ * are a number of implementations in contrib/arm-neon, but the only one that
+ * has partial support is contrib/arm-neon/linux.c - a generic Linux
+ * implementation which reads /proc/cpufino.
+ */
+#ifndef PNG_ARM_NEON_FILE
+# ifdef __linux__
+# define PNG_ARM_NEON_FILE "contrib/arm-neon/linux.c"
+# endif
+#endif
+
+#ifdef PNG_ARM_NEON_FILE
+
+#include <signal.h> /* for sig_atomic_t */
+static int png_have_neon(png_structp png_ptr);
+#include PNG_ARM_NEON_FILE
+
+#else /* PNG_ARM_NEON_FILE */
+# error "PNG_ARM_NEON_FILE undefined: no support for run-time ARM NEON checks"
+#endif /* PNG_ARM_NEON_FILE */
+#endif /* PNG_ARM_NEON_CHECK_SUPPORTED */
+
+#ifndef PNG_ALIGNED_MEMORY_SUPPORTED
+# error "ALIGNED_MEMORY is required; set: -DPNG_ALIGNED_MEMORY_SUPPORTED"
+#endif
+
+void
+png_init_filter_functions_neon(png_structp pp, unsigned int bpp)
+{
+ /* The switch statement is compiled in for ARM_NEON_API, the call to
+ * png_have_neon is compiled in for ARM_NEON_CHECK. If both are defined
+ * the check is only performed if the API has not set the NEON option on
+ * or off explicitly. In this case the check controls what happens.
+ *
+ * If the CHECK is not compiled in and the option is UNSET the behavior prior
+ * to 1.6.7 was to use the NEON code - this was a bug caused by having the
+ * wrong order of the 'ON' and 'default' cases. UNSET now defaults to OFF,
+ * as documented in png.h
+ */
+#ifdef PNG_ARM_NEON_API_SUPPORTED
+ switch ((pp->options >> PNG_ARM_NEON) & 3)
+ {
+ case PNG_OPTION_UNSET:
+ /* Allow the run-time check to execute if it has been enabled -
+ * thus both API and CHECK can be turned on. If it isn't supported
+ * this case will fall through to the 'default' below, which just
+ * returns.
+ */
+#endif /* PNG_ARM_NEON_API_SUPPORTED */
+#ifdef PNG_ARM_NEON_CHECK_SUPPORTED
+ {
+ static volatile sig_atomic_t no_neon = -1; /* not checked */
+
+ if (no_neon < 0)
+ no_neon = !png_have_neon(pp);
+
+ if (no_neon)
+ return;
+ }
+#ifdef PNG_ARM_NEON_API_SUPPORTED
+ break;
+#endif
+#endif /* PNG_ARM_NEON_CHECK_SUPPORTED */
+
+#ifdef PNG_ARM_NEON_API_SUPPORTED
+ default: /* OFF or INVALID */
+ return;
+
+ case PNG_OPTION_ON:
+ /* Option turned on */
+ break;
+ }
+#endif
+
+ /* IMPORTANT: any new external functions used here must be declared using
+ * PNG_INTERNAL_FUNCTION in ../pngpriv.h. This is required so that the
+ * 'prefix' option to configure works:
+ *
+ * ./configure --with-libpng-prefix=foobar_
+ *
+ * Verify you have got this right by running the above command, doing a build
+ * and examining pngprefix.h; it must contain a #define for every external
+ * function you add. (Notice that this happens automatically for the
+ * initialization function.)
+ */
+ pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up_neon;
+
+ if (bpp == 3)
+ {
+ pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_neon;
+ pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_neon;
+ pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
+ png_read_filter_row_paeth3_neon;
+ }
+
+ else if (bpp == 4)
+ {
+ pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_neon;
+ pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_neon;
+ pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
+ png_read_filter_row_paeth4_neon;
+ }
+}
+#endif /* PNG_ARM_NEON_OPT > 0 */
+#endif /* READ */
diff --git a/libpng/arm/filter_neon.S b/libpng/arm/filter_neon.S
new file mode 100644
index 0000000..3b061d6
--- /dev/null
+++ b/libpng/arm/filter_neon.S
@@ -0,0 +1,253 @@
+
+/* filter_neon.S - NEON optimised filter functions
+ *
+ * Copyright (c) 2014 Glenn Randers-Pehrson
+ * Written by Mans Rullgard, 2011.
+ * Last changed in libpng 1.6.16 [December 22, 2014]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+
+/* This is required to get the symbol renames, which are #defines, and the
+ * definitions (or not) of PNG_ARM_NEON_OPT and PNG_ARM_NEON_IMPLEMENTATION.
+ */
+#define PNG_VERSION_INFO_ONLY
+#include "../pngpriv.h"
+
+#if defined(__linux__) && defined(__ELF__)
+.section .note.GNU-stack,"",%progbits /* mark stack as non-executable */
+#endif
+
+#ifdef PNG_READ_SUPPORTED
+
+/* Assembler NEON support - only works for 32-bit ARM (i.e. it does not work for
+ * ARM64). The code in arm/filter_neon_intrinsics.c supports ARM64, however it
+ * only works if -mfpu=neon is specified on the GCC command line. See pngpriv.h
+ * for the logic which sets PNG_USE_ARM_NEON_ASM:
+ */
+#if PNG_ARM_NEON_IMPLEMENTATION == 2 /* hand-coded assembler */
+
+#if PNG_ARM_NEON_OPT > 0
+
+#ifdef __ELF__
+# define ELF
+#else
+# define ELF @
+#endif
+
+ .arch armv7-a
+ .fpu neon
+
+.macro func name, export=0
+ .macro endfunc
+ELF .size \name, . - \name
+ .endfunc
+ .purgem endfunc
+ .endm
+ .text
+
+ /* Explicitly specifying alignment here because some versions of
+ * GAS don't align code correctly. This is harmless in correctly
+ * written versions of GAS.
+ */
+ .align 2
+
+ .if \export
+ .global \name
+ .endif
+ELF .type \name, STT_FUNC
+ .func \name
+\name:
+.endm
+
+func png_read_filter_row_sub4_neon, export=1
+ ldr r3, [r0, #4] @ rowbytes
+ vmov.i8 d3, #0
+1:
+ vld4.32 {d4[],d5[],d6[],d7[]}, [r1,:128]
+ vadd.u8 d0, d3, d4
+ vadd.u8 d1, d0, d5
+ vadd.u8 d2, d1, d6
+ vadd.u8 d3, d2, d7
+ vst4.32 {d0[0],d1[0],d2[0],d3[0]},[r1,:128]!
+ subs r3, r3, #16
+ bgt 1b
+
+ bx lr
+endfunc
+
+func png_read_filter_row_sub3_neon, export=1
+ ldr r3, [r0, #4] @ rowbytes
+ vmov.i8 d3, #0
+ mov r0, r1
+ mov r2, #3
+ mov r12, #12
+ vld1.8 {q11}, [r0], r12
+1:
+ vext.8 d5, d22, d23, #3
+ vadd.u8 d0, d3, d22
+ vext.8 d6, d22, d23, #6
+ vadd.u8 d1, d0, d5
+ vext.8 d7, d23, d23, #1
+ vld1.8 {q11}, [r0], r12
+ vst1.32 {d0[0]}, [r1,:32], r2
+ vadd.u8 d2, d1, d6
+ vst1.32 {d1[0]}, [r1], r2
+ vadd.u8 d3, d2, d7
+ vst1.32 {d2[0]}, [r1], r2
+ vst1.32 {d3[0]}, [r1], r2
+ subs r3, r3, #12
+ bgt 1b
+
+ bx lr
+endfunc
+
+func png_read_filter_row_up_neon, export=1
+ ldr r3, [r0, #4] @ rowbytes
+1:
+ vld1.8 {q0}, [r1,:128]
+ vld1.8 {q1}, [r2,:128]!
+ vadd.u8 q0, q0, q1
+ vst1.8 {q0}, [r1,:128]!
+ subs r3, r3, #16
+ bgt 1b
+
+ bx lr
+endfunc
+
+func png_read_filter_row_avg4_neon, export=1
+ ldr r12, [r0, #4] @ rowbytes
+ vmov.i8 d3, #0
+1:
+ vld4.32 {d4[],d5[],d6[],d7[]}, [r1,:128]
+ vld4.32 {d16[],d17[],d18[],d19[]},[r2,:128]!
+ vhadd.u8 d0, d3, d16
+ vadd.u8 d0, d0, d4
+ vhadd.u8 d1, d0, d17
+ vadd.u8 d1, d1, d5
+ vhadd.u8 d2, d1, d18
+ vadd.u8 d2, d2, d6
+ vhadd.u8 d3, d2, d19
+ vadd.u8 d3, d3, d7
+ vst4.32 {d0[0],d1[0],d2[0],d3[0]},[r1,:128]!
+ subs r12, r12, #16
+ bgt 1b
+
+ bx lr
+endfunc
+
+func png_read_filter_row_avg3_neon, export=1
+ push {r4,lr}
+ ldr r12, [r0, #4] @ rowbytes
+ vmov.i8 d3, #0
+ mov r0, r1
+ mov r4, #3
+ mov lr, #12
+ vld1.8 {q11}, [r0], lr
+1:
+ vld1.8 {q10}, [r2], lr
+ vext.8 d5, d22, d23, #3
+ vhadd.u8 d0, d3, d20
+ vext.8 d17, d20, d21, #3
+ vadd.u8 d0, d0, d22
+ vext.8 d6, d22, d23, #6
+ vhadd.u8 d1, d0, d17
+ vext.8 d18, d20, d21, #6
+ vadd.u8 d1, d1, d5
+ vext.8 d7, d23, d23, #1
+ vld1.8 {q11}, [r0], lr
+ vst1.32 {d0[0]}, [r1,:32], r4
+ vhadd.u8 d2, d1, d18
+ vst1.32 {d1[0]}, [r1], r4
+ vext.8 d19, d21, d21, #1
+ vadd.u8 d2, d2, d6
+ vhadd.u8 d3, d2, d19
+ vst1.32 {d2[0]}, [r1], r4
+ vadd.u8 d3, d3, d7
+ vst1.32 {d3[0]}, [r1], r4
+ subs r12, r12, #12
+ bgt 1b
+
+ pop {r4,pc}
+endfunc
+
+.macro paeth rx, ra, rb, rc
+ vaddl.u8 q12, \ra, \rb @ a + b
+ vaddl.u8 q15, \rc, \rc @ 2*c
+ vabdl.u8 q13, \rb, \rc @ pa
+ vabdl.u8 q14, \ra, \rc @ pb
+ vabd.u16 q15, q12, q15 @ pc
+ vcle.u16 q12, q13, q14 @ pa <= pb
+ vcle.u16 q13, q13, q15 @ pa <= pc
+ vcle.u16 q14, q14, q15 @ pb <= pc
+ vand q12, q12, q13 @ pa <= pb && pa <= pc
+ vmovn.u16 d28, q14
+ vmovn.u16 \rx, q12
+ vbsl d28, \rb, \rc
+ vbsl \rx, \ra, d28
+.endm
+
+func png_read_filter_row_paeth4_neon, export=1
+ ldr r12, [r0, #4] @ rowbytes
+ vmov.i8 d3, #0
+ vmov.i8 d20, #0
+1:
+ vld4.32 {d4[],d5[],d6[],d7[]}, [r1,:128]
+ vld4.32 {d16[],d17[],d18[],d19[]},[r2,:128]!
+ paeth d0, d3, d16, d20
+ vadd.u8 d0, d0, d4
+ paeth d1, d0, d17, d16
+ vadd.u8 d1, d1, d5
+ paeth d2, d1, d18, d17
+ vadd.u8 d2, d2, d6
+ paeth d3, d2, d19, d18
+ vmov d20, d19
+ vadd.u8 d3, d3, d7
+ vst4.32 {d0[0],d1[0],d2[0],d3[0]},[r1,:128]!
+ subs r12, r12, #16
+ bgt 1b
+
+ bx lr
+endfunc
+
+func png_read_filter_row_paeth3_neon, export=1
+ push {r4,lr}
+ ldr r12, [r0, #4] @ rowbytes
+ vmov.i8 d3, #0
+ vmov.i8 d4, #0
+ mov r0, r1
+ mov r4, #3
+ mov lr, #12
+ vld1.8 {q11}, [r0], lr
+1:
+ vld1.8 {q10}, [r2], lr
+ paeth d0, d3, d20, d4
+ vext.8 d5, d22, d23, #3
+ vadd.u8 d0, d0, d22
+ vext.8 d17, d20, d21, #3
+ paeth d1, d0, d17, d20
+ vst1.32 {d0[0]}, [r1,:32], r4
+ vext.8 d6, d22, d23, #6
+ vadd.u8 d1, d1, d5
+ vext.8 d18, d20, d21, #6
+ paeth d2, d1, d18, d17
+ vext.8 d7, d23, d23, #1
+ vld1.8 {q11}, [r0], lr
+ vst1.32 {d1[0]}, [r1], r4
+ vadd.u8 d2, d2, d6
+ vext.8 d19, d21, d21, #1
+ paeth d3, d2, d19, d18
+ vst1.32 {d2[0]}, [r1], r4
+ vmov d4, d19
+ vadd.u8 d3, d3, d7
+ vst1.32 {d3[0]}, [r1], r4
+ subs r12, r12, #12
+ bgt 1b
+
+ pop {r4,pc}
+endfunc
+#endif /* PNG_ARM_NEON_OPT > 0 */
+#endif /* PNG_ARM_NEON_IMPLEMENTATION == 2 (assembler) */
+#endif /* READ */
diff --git a/libpng/arm/filter_neon_intrinsics.c b/libpng/arm/filter_neon_intrinsics.c
new file mode 100644
index 0000000..d42c788
--- /dev/null
+++ b/libpng/arm/filter_neon_intrinsics.c
@@ -0,0 +1,373 @@
+
+/* filter_neon_intrinsics.c - NEON optimised filter functions
+ *
+ * Copyright (c) 2014 Glenn Randers-Pehrson
+ * Written by James Yu <james.yu at linaro.org>, October 2013.
+ * Based on filter_neon.S, written by Mans Rullgard, 2011.
+ *
+ * Last changed in libpng 1.6.16 [December 22, 2014]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+
+#include "../pngpriv.h"
+
+#ifdef PNG_READ_SUPPORTED
+
+/* This code requires -mfpu=neon on the command line: */
+#if PNG_ARM_NEON_IMPLEMENTATION == 1 /* intrinsics code from pngpriv.h */
+
+#include <arm_neon.h>
+
+/* libpng row pointers are not necessarily aligned to any particular boundary,
+ * however this code will only work with appropriate alignment. arm/arm_init.c
+ * checks for this (and will not compile unless it is done). This code uses
+ * variants of png_aligncast to avoid compiler warnings.
+ */
+#define png_ptr(type,pointer) png_aligncast(type *,pointer)
+#define png_ptrc(type,pointer) png_aligncastconst(const type *,pointer)
+
+/* The following relies on a variable 'temp_pointer' being declared with type
+ * 'type'. This is written this way just to hide the GCC strict aliasing
+ * warning; note that the code is safe because there never is an alias between
+ * the input and output pointers.
+ */
+#define png_ldr(type,pointer)\
+ (temp_pointer = png_ptr(type,pointer), *temp_pointer)
+
+#if PNG_ARM_NEON_OPT > 0
+
+void
+png_read_filter_row_up_neon(png_row_infop row_info, png_bytep row,
+ png_const_bytep prev_row)
+{
+ png_bytep rp = row;
+ png_bytep rp_stop = row + row_info->rowbytes;
+ png_const_bytep pp = prev_row;
+
+ for (; rp < rp_stop; rp += 16, pp += 16)
+ {
+ uint8x16_t qrp, qpp;
+
+ qrp = vld1q_u8(rp);
+ qpp = vld1q_u8(pp);
+ qrp = vaddq_u8(qrp, qpp);
+ vst1q_u8(rp, qrp);
+ }
+}
+
+void
+png_read_filter_row_sub3_neon(png_row_infop row_info, png_bytep row,
+ png_const_bytep prev_row)
+{
+ png_bytep rp = row;
+ png_bytep rp_stop = row + row_info->rowbytes;
+
+ uint8x16_t vtmp = vld1q_u8(rp);
+ uint8x8x2_t *vrpt = png_ptr(uint8x8x2_t, &vtmp);
+ uint8x8x2_t vrp = *vrpt;
+
+ uint8x8x4_t vdest;
+ vdest.val[3] = vdup_n_u8(0);
+
+ for (; rp < rp_stop;)
+ {
+ uint8x8_t vtmp1, vtmp2;
+ uint32x2_t *temp_pointer;
+
+ vtmp1 = vext_u8(vrp.val[0], vrp.val[1], 3);
+ vdest.val[0] = vadd_u8(vdest.val[3], vrp.val[0]);
+ vtmp2 = vext_u8(vrp.val[0], vrp.val[1], 6);
+ vdest.val[1] = vadd_u8(vdest.val[0], vtmp1);
+
+ vtmp1 = vext_u8(vrp.val[1], vrp.val[1], 1);
+ vdest.val[2] = vadd_u8(vdest.val[1], vtmp2);
+ vdest.val[3] = vadd_u8(vdest.val[2], vtmp1);
+
+ vtmp = vld1q_u8(rp + 12);
+ vrpt = png_ptr(uint8x8x2_t, &vtmp);
+ vrp = *vrpt;
+
+ vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[0]), 0);
+ rp += 3;
+ vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[1]), 0);
+ rp += 3;
+ vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[2]), 0);
+ rp += 3;
+ vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[3]), 0);
+ rp += 3;
+ }
+
+ PNG_UNUSED(prev_row)
+}
+
+void
+png_read_filter_row_sub4_neon(png_row_infop row_info, png_bytep row,
+ png_const_bytep prev_row)
+{
+ png_bytep rp = row;
+ png_bytep rp_stop = row + row_info->rowbytes;
+
+ uint8x8x4_t vdest;
+ vdest.val[3] = vdup_n_u8(0);
+
+ for (; rp < rp_stop; rp += 16)
+ {
+ uint32x2x4_t vtmp = vld4_u32(png_ptr(uint32_t,rp));
+ uint8x8x4_t *vrpt = png_ptr(uint8x8x4_t,&vtmp);
+ uint8x8x4_t vrp = *vrpt;
+ uint32x2x4_t *temp_pointer;
+
+ vdest.val[0] = vadd_u8(vdest.val[3], vrp.val[0]);
+ vdest.val[1] = vadd_u8(vdest.val[0], vrp.val[1]);
+ vdest.val[2] = vadd_u8(vdest.val[1], vrp.val[2]);
+ vdest.val[3] = vadd_u8(vdest.val[2], vrp.val[3]);
+ vst4_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2x4_t,&vdest), 0);
+ }
+
+ PNG_UNUSED(prev_row)
+}
+
+void
+png_read_filter_row_avg3_neon(png_row_infop row_info, png_bytep row,
+ png_const_bytep prev_row)
+{
+ png_bytep rp = row;
+ png_const_bytep pp = prev_row;
+ png_bytep rp_stop = row + row_info->rowbytes;
+
+ uint8x16_t vtmp;
+ uint8x8x2_t *vrpt;
+ uint8x8x2_t vrp;
+ uint8x8x4_t vdest;
+ vdest.val[3] = vdup_n_u8(0);
+
+ vtmp = vld1q_u8(rp);
+ vrpt = png_ptr(uint8x8x2_t,&vtmp);
+ vrp = *vrpt;
+
+ for (; rp < rp_stop; pp += 12)
+ {
+ uint8x8_t vtmp1, vtmp2, vtmp3;
+
+ uint8x8x2_t *vppt;
+ uint8x8x2_t vpp;
+
+ uint32x2_t *temp_pointer;
+
+ vtmp = vld1q_u8(pp);
+ vppt = png_ptr(uint8x8x2_t,&vtmp);
+ vpp = *vppt;
+
+ vtmp1 = vext_u8(vrp.val[0], vrp.val[1], 3);
+ vdest.val[0] = vhadd_u8(vdest.val[3], vpp.val[0]);
+ vdest.val[0] = vadd_u8(vdest.val[0], vrp.val[0]);
+
+ vtmp2 = vext_u8(vpp.val[0], vpp.val[1], 3);
+ vtmp3 = vext_u8(vrp.val[0], vrp.val[1], 6);
+ vdest.val[1] = vhadd_u8(vdest.val[0], vtmp2);
+ vdest.val[1] = vadd_u8(vdest.val[1], vtmp1);
+
+ vtmp2 = vext_u8(vpp.val[0], vpp.val[1], 6);
+ vtmp1 = vext_u8(vrp.val[1], vrp.val[1], 1);
+
+ vtmp = vld1q_u8(rp + 12);
+ vrpt = png_ptr(uint8x8x2_t,&vtmp);
+ vrp = *vrpt;
+
+ vdest.val[2] = vhadd_u8(vdest.val[1], vtmp2);
+ vdest.val[2] = vadd_u8(vdest.val[2], vtmp3);
+
+ vtmp2 = vext_u8(vpp.val[1], vpp.val[1], 1);
+
+ vdest.val[3] = vhadd_u8(vdest.val[2], vtmp2);
+ vdest.val[3] = vadd_u8(vdest.val[3], vtmp1);
+
+ vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[0]), 0);
+ rp += 3;
+ vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[1]), 0);
+ rp += 3;
+ vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[2]), 0);
+ rp += 3;
+ vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[3]), 0);
+ rp += 3;
+ }
+}
+
+void
+png_read_filter_row_avg4_neon(png_row_infop row_info, png_bytep row,
+ png_const_bytep prev_row)
+{
+ png_bytep rp = row;
+ png_bytep rp_stop = row + row_info->rowbytes;
+ png_const_bytep pp = prev_row;
+
+ uint8x8x4_t vdest;
+ vdest.val[3] = vdup_n_u8(0);
+
+ for (; rp < rp_stop; rp += 16, pp += 16)
+ {
+ uint32x2x4_t vtmp;
+ uint8x8x4_t *vrpt, *vppt;
+ uint8x8x4_t vrp, vpp;
+ uint32x2x4_t *temp_pointer;
+
+ vtmp = vld4_u32(png_ptr(uint32_t,rp));
+ vrpt = png_ptr(uint8x8x4_t,&vtmp);
+ vrp = *vrpt;
+ vtmp = vld4_u32(png_ptrc(uint32_t,pp));
+ vppt = png_ptr(uint8x8x4_t,&vtmp);
+ vpp = *vppt;
+
+ vdest.val[0] = vhadd_u8(vdest.val[3], vpp.val[0]);
+ vdest.val[0] = vadd_u8(vdest.val[0], vrp.val[0]);
+ vdest.val[1] = vhadd_u8(vdest.val[0], vpp.val[1]);
+ vdest.val[1] = vadd_u8(vdest.val[1], vrp.val[1]);
+ vdest.val[2] = vhadd_u8(vdest.val[1], vpp.val[2]);
+ vdest.val[2] = vadd_u8(vdest.val[2], vrp.val[2]);
+ vdest.val[3] = vhadd_u8(vdest.val[2], vpp.val[3]);
+ vdest.val[3] = vadd_u8(vdest.val[3], vrp.val[3]);
+
+ vst4_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2x4_t,&vdest), 0);
+ }
+}
+
+static uint8x8_t
+paeth(uint8x8_t a, uint8x8_t b, uint8x8_t c)
+{
+ uint8x8_t d, e;
+ uint16x8_t p1, pa, pb, pc;
+
+ p1 = vaddl_u8(a, b); /* a + b */
+ pc = vaddl_u8(c, c); /* c * 2 */
+ pa = vabdl_u8(b, c); /* pa */
+ pb = vabdl_u8(a, c); /* pb */
+ pc = vabdq_u16(p1, pc); /* pc */
+
+ p1 = vcleq_u16(pa, pb); /* pa <= pb */
+ pa = vcleq_u16(pa, pc); /* pa <= pc */
+ pb = vcleq_u16(pb, pc); /* pb <= pc */
+
+ p1 = vandq_u16(p1, pa); /* pa <= pb && pa <= pc */
+
+ d = vmovn_u16(pb);
+ e = vmovn_u16(p1);
+
+ d = vbsl_u8(d, b, c);
+ e = vbsl_u8(e, a, d);
+
+ return e;
+}
+
+void
+png_read_filter_row_paeth3_neon(png_row_infop row_info, png_bytep row,
+ png_const_bytep prev_row)
+{
+ png_bytep rp = row;
+ png_const_bytep pp = prev_row;
+ png_bytep rp_stop = row + row_info->rowbytes;
+
+ uint8x16_t vtmp;
+ uint8x8x2_t *vrpt;
+ uint8x8x2_t vrp;
+ uint8x8_t vlast = vdup_n_u8(0);
+ uint8x8x4_t vdest;
+ vdest.val[3] = vdup_n_u8(0);
+
+ vtmp = vld1q_u8(rp);
+ vrpt = png_ptr(uint8x8x2_t,&vtmp);
+ vrp = *vrpt;
+
+ for (; rp < rp_stop; pp += 12)
+ {
+ uint8x8x2_t *vppt;
+ uint8x8x2_t vpp;
+ uint8x8_t vtmp1, vtmp2, vtmp3;
+ uint32x2_t *temp_pointer;
+
+ vtmp = vld1q_u8(pp);
+ vppt = png_ptr(uint8x8x2_t,&vtmp);
+ vpp = *vppt;
+
+ vdest.val[0] = paeth(vdest.val[3], vpp.val[0], vlast);
+ vdest.val[0] = vadd_u8(vdest.val[0], vrp.val[0]);
+
+ vtmp1 = vext_u8(vrp.val[0], vrp.val[1], 3);
+ vtmp2 = vext_u8(vpp.val[0], vpp.val[1], 3);
+ vdest.val[1] = paeth(vdest.val[0], vtmp2, vpp.val[0]);
+ vdest.val[1] = vadd_u8(vdest.val[1], vtmp1);
+
+ vtmp1 = vext_u8(vrp.val[0], vrp.val[1], 6);
+ vtmp3 = vext_u8(vpp.val[0], vpp.val[1], 6);
+ vdest.val[2] = paeth(vdest.val[1], vtmp3, vtmp2);
+ vdest.val[2] = vadd_u8(vdest.val[2], vtmp1);
+
+ vtmp1 = vext_u8(vrp.val[1], vrp.val[1], 1);
+ vtmp2 = vext_u8(vpp.val[1], vpp.val[1], 1);
+
+ vtmp = vld1q_u8(rp + 12);
+ vrpt = png_ptr(uint8x8x2_t,&vtmp);
+ vrp = *vrpt;
+
+ vdest.val[3] = paeth(vdest.val[2], vtmp2, vtmp3);
+ vdest.val[3] = vadd_u8(vdest.val[3], vtmp1);
+
+ vlast = vtmp2;
+
+ vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[0]), 0);
+ rp += 3;
+ vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[1]), 0);
+ rp += 3;
+ vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[2]), 0);
+ rp += 3;
+ vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[3]), 0);
+ rp += 3;
+ }
+}
+
+void
+png_read_filter_row_paeth4_neon(png_row_infop row_info, png_bytep row,
+ png_const_bytep prev_row)
+{
+ png_bytep rp = row;
+ png_bytep rp_stop = row + row_info->rowbytes;
+ png_const_bytep pp = prev_row;
+
+ uint8x8_t vlast = vdup_n_u8(0);
+ uint8x8x4_t vdest;
+ vdest.val[3] = vdup_n_u8(0);
+
+ for (; rp < rp_stop; rp += 16, pp += 16)
+ {
+ uint32x2x4_t vtmp;
+ uint8x8x4_t *vrpt, *vppt;
+ uint8x8x4_t vrp, vpp;
+ uint32x2x4_t *temp_pointer;
+
+ vtmp = vld4_u32(png_ptr(uint32_t,rp));
+ vrpt = png_ptr(uint8x8x4_t,&vtmp);
+ vrp = *vrpt;
+ vtmp = vld4_u32(png_ptrc(uint32_t,pp));
+ vppt = png_ptr(uint8x8x4_t,&vtmp);
+ vpp = *vppt;
+
+ vdest.val[0] = paeth(vdest.val[3], vpp.val[0], vlast);
+ vdest.val[0] = vadd_u8(vdest.val[0], vrp.val[0]);
+ vdest.val[1] = paeth(vdest.val[0], vpp.val[1], vpp.val[0]);
+ vdest.val[1] = vadd_u8(vdest.val[1], vrp.val[1]);
+ vdest.val[2] = paeth(vdest.val[1], vpp.val[2], vpp.val[1]);
+ vdest.val[2] = vadd_u8(vdest.val[2], vrp.val[2]);
+ vdest.val[3] = paeth(vdest.val[2], vpp.val[3], vpp.val[2]);
+ vdest.val[3] = vadd_u8(vdest.val[3], vrp.val[3]);
+
+ vlast = vpp.val[3];
+
+ vst4_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2x4_t,&vdest), 0);
+ }
+}
+
+#endif /* PNG_ARM_NEON_OPT > 0 */
+#endif /* PNG_ARM_NEON_IMPLEMENTATION == 1 (intrinsics) */
+#endif /* READ */
diff --git a/libpng/autogen.sh b/libpng/autogen.sh
new file mode 100755
index 0000000..9160717
--- /dev/null
+++ b/libpng/autogen.sh
@@ -0,0 +1,225 @@
+#! /bin/sh
+#
+# Run 'autoreconf' to build 'configure', 'Makefile.in' and other configure
+# control files.
+#
+# The first time this is run on a GIT checkout the only files that exist are
+# configure.ac and Makefile.am; all of the autotools support scripts are
+# missing. They are instantiated with autoreconf --force --install.
+#
+# For regular ("tarball") distributions all the files should exist. We do not
+# want them to be updated *under any circumstances*. It should never be
+# necessary to run autogen.sh because ./configure --enable-maintainer-mode says
+# what to do if Makefile.am or configure.ac are changed.
+#
+# It is *probably* OK to update the files on a GIT checkout, because they have
+# come from the local tools, but leave that to the user who is assumed to know
+# whether it is ok or required.
+#
+# This script is intended to work without arguments, there are, however, hidden
+# arguments (a) for use while testing the script and (b) to fix up systems that
+# have been broken. If (b) is required the script prompts for the correct
+# options. For this reason the options are *NOT* documented in the help; this
+# is deliberate; UTSL.
+#
+clean=
+maintainer=
+while test $# -gt 0
+do
+ case "$1" in
+ --maintainer)
+ maintainer=1;;
+
+ --clean)
+ clean=1;;
+
+ *)
+ exec >&2
+ echo "$0: usage: ./autogen.sh"
+ if test -d .git
+ then
+ echo " ./autogen.sh generates the configure script and"
+ echo " Makefile.in, or refreshes them after changes to Makefile.am"
+ echo " or configure.ac. You may prefer to just run autoreconf."
+ elif test -z "$maintainer"
+ then
+ echo " DO NOT RUN THIS SCRIPT."
+ echo " If you need to change Makefile.am or configure.ac then you"
+ echo " also need to run ./configure --enable-maintainer-mode and"
+ echo " use the appropriate autotools, *NOT* this script, to update"
+ echo " everything, please check the documentation of autoreconf."
+ echo " WARNING: libpng is intentionally generated with a known,"
+ echo " fixed, set of autotools. It is known *NOT* to work with"
+ echo " the collection of autotools distributed on highly reputable"
+ echo " operating systems."
+ echo " Remember: autotools is GNU software, you are expected to"
+ echo " pay for support."
+ else
+ echo " You have run autogen.sh with --maintainer enabled and you"
+ echo " are not using a GIT distribution, then you have given an"
+ echo " unrecognized argument. This is not good. --maintainer"
+ echo " switches off any assumptions that you might not know what"
+ echo " you are doing."
+ fi
+ exit 1;;
+ esac
+
+ shift
+done
+#
+# First check for a set of the autotools files; if absent then this is assumed
+# to be a GIT version and the local autotools must be used. If present this
+# is a tarball distribution and the script should not be used. If partially
+# present bad things are happening.
+#
+# The autotools generated files:
+libpng_autotools_files="Makefile.in aclocal.m4 config.guess config.h.in
+ config.sub configure depcomp install-sh ltmain.sh missing\
+ test-driver"
+#
+# Files generated by versions of configue >2.68 or automake >1.13 (i.e. later
+# versions than those required by configure.ac):
+libpng_autotools_extra="compile config.h.in~"
+#
+# These are separate because 'maintainer-clean' does not remove them.
+libpng_libtool_files="scripts/libtool.m4 scripts/ltoptions.m4\
+ scripts/ltsugar.m4 scripts/ltversion.m4 scripts/lt~obsolete.m4"
+
+libpng_autotools_dirs="autom4te.cache" # not required
+#
+# The configure generated files:
+libpng_configure_files="Makefile config.h config.log config.status\
+ libpng-config libpng.pc libtool stamp-h1"
+
+libpng_configure_dirs=".deps"
+#
+# We must remove the configure generated files as well as the autotools
+# generated files if autotools are regenerated because otherwise if configure
+# has been run without "--enable-maintainer-mode" make can do a partial update
+# of Makefile. These functions do the two bits of cleaning.
+clean_autotools(){
+ rm -rf $libpng_autotools_files $libpng_libtool_files $libpng_autotools_dirs
+ rm -rf $libpng_autotools_extra
+}
+
+clean_configure(){
+ rm -rf $libpng_configure_files $libpng_configure_dirs
+}
+#
+# Clean: remove everything (this is to help with testing)
+if test -n "$clean"
+then
+ clean_configure
+ if test -n "$maintainer"
+ then
+ clean_autotools
+ fi
+
+ exit 0
+fi
+#
+# Validate the distribution.
+libpng_autotools_file_found=
+libpng_autotools_file_missing=
+for file in $libpng_autotools_files
+do
+ if test -f "$file"
+ then
+ libpng_autotools_file_found=1
+ else
+ libpng_autotools_file_missing=1
+ fi
+done
+#
+# Presence of one of these does not *invalidate* missing, but absence
+# invalidates found.
+for file in $libpng_libtool_files
+do
+ if test ! -f "$file"
+ then
+ libpng_autotools_file_missing=1
+ fi
+done
+#
+# The cache directory doesn't matter - it will be regenerated and does not exist
+# anyway in a tarball.
+#
+# Either everything is missing or everything is there, the --maintainer option
+# just changes this so that the mode is set to generate all the files.
+mode=
+if test -z "$libpng_autotools_file_found" -o -n "$maintainer"
+then
+ mode="autoreconf"
+else
+ if test -n "$libpng_autotools_file_missing"
+ then
+ mode="broken"
+ else
+ mode="configure"
+ fi
+fi
+#
+# So:
+case "$mode" in
+ autoreconf)
+ # Clean in case configure files exist
+ clean_configure
+ clean_autotools
+ # Everything must be initialized, so use --force
+ if autoreconf --warnings=all --force --install
+ then
+ missing=
+ for file in $libpng_autotools_files
+ do
+ test -f "$file" || missing=1
+ done
+ # ignore the cache directory
+ test -z "$missing" || {
+ exec >&2
+ echo "autoreconf was run, but did not produce all the expected"
+ echo "files. It is likely that your autotools installation is"
+ echo "not compatible with that expected by libpng."
+ exit 1
+ }
+ else
+ exec >&2
+ echo "autoreconf failed: your version of autotools is incompatible"
+ echo "with this libpng version. Please use a distributed archive"
+ echo "(which includes the autotools generated files) and run configure"
+ echo "instead."
+ exit 1
+ fi;;
+
+ configure)
+ if test -d .git
+ then
+ exec >&2
+ echo "ERROR: running autoreconf on an initialized sytem"
+ echo " This is not necessary; it is only necessary to remake the"
+ echo " autotools generated files if Makefile.am or configure.ac"
+ echo " change and make does the right thing with:"
+ echo
+ echo " ./configure --enable-maintainer-mode."
+ echo
+ echo " You can run autoreconf yourself if you don't like maintainer"
+ echo " mode and you can also just run autoreconf -f -i to initialize"
+ echo " everything in the first place; this script is only for"
+ echo " compatibility with prior releases."
+ exit 1
+ else
+ exec >&2
+ echo "autogen.sh is intended only to generate 'configure' on systems"
+ echo "that do not have it. You have a complete 'configure', if you"
+ echo "need to change Makefile.am or configure.ac you also need to"
+ echo "run configure with the --enable-maintainer-mode option."
+ exit 1
+ fi;;
+
+ broken)
+ exec >&2
+ echo "Your system has a partial set of autotools generated files."
+ echo "autogen.sh is unable to proceed. The full set of files is"
+ echo "contained in the libpng 'tar' distribution archive and you do"
+ echo "not need to run autogen.sh if you use it."
+ exit 1;;
+esac
diff --git a/libpng/configure.ac b/libpng/configure.ac
new file mode 100644
index 0000000..845ae1c
--- /dev/null
+++ b/libpng/configure.ac
@@ -0,0 +1,324 @@
+# configure.ac
+
+dnl Process this file with autoconf to produce a configure script.
+dnl
+dnl Minor upgrades (compatible ABI): increment the package version
+dnl (third field in two places below) and set the PNGLIB_RELEASE
+dnl variable.
+dnl
+dnl Major upgrades (incompatible ABI): increment the package major
+dnl version (second field, or first if desired), set the minor
+dnl to 0, set PNGLIB_MAJOR below *and* follow the instructions in
+dnl Makefile.am to upgrade the package name.
+
+dnl This is here to prevent earlier autoconf from being used, it
+dnl should not be necessary to regenerate configure if the time
+dnl stamps are correct
+AC_PREREQ([2.68])
+
+dnl Version number stuff here:
+
+AC_INIT([libpng],[1.6.20],[png-mng-implement@lists.sourceforge.net])
+AC_CONFIG_MACRO_DIR([scripts])
+
+# libpng does not follow GNU file name conventions (hence 'foreign')
+# color-tests requires automake 1.11 or later
+# silent-rules requires automake 1.11 or later
+# dist-xz requires automake 1.11 or later
+# 1.12.2 fixes a security issue in 1.11.2 and 1.12.1
+# 1.13 is required for parallel tests
+AM_INIT_AUTOMAKE([1.13 foreign dist-xz color-tests silent-rules subdir-objects])
+# The following line causes --disable-maintainer-mode to be the default to
+# configure, this is necessary because libpng distributions cannot rely on the
+# time stamps of the autotools generated files being correct
+AM_MAINTAINER_MODE
+
+dnl configure.ac and Makefile.am expect automake 1.11.2 or a compatible later
+dnl version; aclocal.m4 will generate a failure if you use a prior version of
+dnl automake, so the following is not necessary (and is not defined anyway):
+dnl AM_PREREQ([1.11.2])
+dnl stop configure from automagically running automake
+
+PNGLIB_VERSION=1.6.20
+PNGLIB_MAJOR=1
+PNGLIB_MINOR=6
+PNGLIB_RELEASE=20
+
+dnl End of version number stuff
+
+AC_CONFIG_SRCDIR([pngget.c])
+AC_CONFIG_HEADERS([config.h])
+
+# Checks for programs.
+AC_LANG([C])
+AC_PROG_CC
+AM_PROG_AS
+LT_PATH_LD
+AC_PROG_CPP
+AC_PROG_AWK
+AC_PROG_INSTALL
+AC_PROG_LN_S
+AC_PROG_MAKE_SET
+
+dnl libtool/libtoolize; version 2.4.2 is the tested version, this or any
+dnl compatible later version may be used
+LT_INIT([win32-dll])
+LT_PREREQ([2.4.2])
+
+# Some awks crash when confronted with pnglibconf.dfa, do a test run now
+# to make sure this doesn't happen
+AC_MSG_CHECKING([that AWK works])
+if ${AWK} -f ${srcdir}/scripts/options.awk out="/dev/null" version=search\
+ ${srcdir}/pngconf.h ${srcdir}/scripts/pnglibconf.dfa\
+ ${srcdir}/pngusr.dfa 1>&2
+then
+ AC_MSG_RESULT([ok])
+else
+ AC_MSG_FAILURE([failed], 1)
+fi
+
+# This is a remnant of the old cc -E validation, where it may have been
+# necessary to use a different preprocessor for .dfn files
+DFNCPP="$CPP"
+AC_SUBST(DFNCPP)
+
+# -Werror cannot be passed to GCC in CFLAGS because configure will fail (it
+# checks the compiler with a program that generates a warning), add the
+# following option to deal with this
+AC_ARG_VAR(PNG_COPTS,
+ [additional flags for the C compiler, use this for options that would]
+ [cause configure itself to fail])
+AC_ARG_ENABLE(werror,
+ AS_HELP_STRING([[[--enable-werror[=OPT]]]],
+ [Pass -Werror or the given argument to the compiler if it is supported]),
+ [test "$enable_werror" = "yes" && enable_werror="-Werror"
+ if test "$enable_werror" != "no"; then
+ sav_CFLAGS="$CFLAGS"
+ CFLAGS="$enable_werror $CFLAGS"
+ AC_MSG_CHECKING([if the compiler allows $enable_werror])
+ AC_COMPILE_IFELSE(
+ [AC_LANG_SOURCE([
+ [int main(int argc, char **argv){]
+ [return argv[argc-1][0];]
+ [}]])],
+ AC_MSG_RESULT(yes)
+ PNG_COPTS="$PNG_COPTS $enable_werror",
+ AC_MSG_RESULT(no))
+ CFLAGS="$sav_CFLAGS"
+ fi],)
+
+# Checks for header files.
+AC_HEADER_STDC
+
+# Checks for typedefs, structures, and compiler characteristics.
+AC_C_CONST
+AC_TYPE_SIZE_T
+AC_STRUCT_TM
+AC_C_RESTRICT
+
+# Checks for library functions.
+AC_FUNC_STRTOD
+AC_CHECK_FUNCS([memset], , AC_MSG_ERROR(memset not found in libc))
+AC_CHECK_FUNCS([pow], , AC_CHECK_LIB(m, pow, , AC_MSG_ERROR(cannot find pow)) )
+AC_ARG_WITH(zlib-prefix,
+ AS_HELP_STRING([[[--with-zlib-prefix]]],
+ [prefix that may have been used in installed zlib]),
+ [ZPREFIX=${withval}],
+ [ZPREFIX='z_'])
+AC_CHECK_LIB(z, zlibVersion, ,
+ AC_CHECK_LIB(z, ${ZPREFIX}zlibVersion, , AC_MSG_ERROR(zlib not installed)))
+
+# The following is for pngvalid, to ensure it catches FP errors even on
+# platforms that don't enable FP exceptions, the function appears in the math
+# library (typically), it's not an error if it is not found.
+AC_CHECK_LIB([m], [feenableexcept])
+AC_CHECK_FUNCS([feenableexcept])
+
+AC_MSG_CHECKING([if using Solaris linker])
+SLD=`$LD --version 2>&1 | grep Solaris`
+if test "$SLD"; then
+ have_solaris_ld=yes
+ AC_MSG_RESULT(yes)
+else
+ have_solaris_ld=no
+ AC_MSG_RESULT(no)
+fi
+AM_CONDITIONAL(HAVE_SOLARIS_LD, test "$have_solaris_ld" = "yes")
+
+AC_MSG_CHECKING([if libraries can be versioned])
+# Special case for PE/COFF platforms: ld reports
+# support for version-script, but doesn't actually
+# DO anything with it.
+case $host in
+*cygwin* | *mingw32* | *interix* )
+ have_ld_version_script=no
+ AC_MSG_RESULT(no)
+;;
+* )
+
+if test "$have_solaris_ld" = "yes"; then
+ GLD=`$LD --help < /dev/null 2>&1 | grep 'M mapfile'`
+else
+ GLD=`$LD --help < /dev/null 2>/dev/null | grep version-script`
+fi
+
+if test "$GLD"; then
+ have_ld_version_script=yes
+ AC_MSG_RESULT(yes)
+else
+ have_ld_version_script=no
+ AC_MSG_RESULT(no)
+ AC_MSG_WARN(*** You have not enabled versioned symbols.)
+fi
+;;
+esac
+
+AM_CONDITIONAL(HAVE_LD_VERSION_SCRIPT, test "$have_ld_version_script" = "yes")
+
+if test "$have_ld_version_script" = "yes"; then
+ AC_MSG_CHECKING([for symbol prefix])
+ SYMBOL_PREFIX=`echo "PREFIX=__USER_LABEL_PREFIX__" \
+ | ${CPP-${CC-gcc} -E} - 2>&1 \
+ | ${EGREP-grep} "^PREFIX=" \
+ | ${SED-sed} -e "s:^PREFIX=::" -e "s:__USER_LABEL_PREFIX__::"`
+ AC_SUBST(SYMBOL_PREFIX)
+ AC_MSG_RESULT($SYMBOL_PREFIX)
+fi
+
+# Substitutions for .in files
+AC_SUBST(PNGLIB_VERSION)
+AC_SUBST(PNGLIB_MAJOR)
+AC_SUBST(PNGLIB_MINOR)
+AC_SUBST(PNGLIB_RELEASE)
+
+# Additional arguments (and substitutions)
+# Allow the pkg-config directory to be set
+AC_ARG_WITH(pkgconfigdir,
+ AS_HELP_STRING([[[--with-pkgconfigdir]]],
+ [Use the specified pkgconfig dir (default is libdir/pkgconfig)]),
+ [pkgconfigdir=${withval}],
+ [pkgconfigdir='${libdir}/pkgconfig'])
+
+AC_SUBST([pkgconfigdir])
+AC_MSG_NOTICE([[pkgconfig directory is ${pkgconfigdir}]])
+
+# Make the *-config binary config scripts optional
+AC_ARG_WITH(binconfigs,
+ AS_HELP_STRING([[[--with-binconfigs]]],
+ [Generate shell libpng-config scripts as well as pkg-config data]
+ [@<:@default=yes@:>@]),
+ [if test "${withval}" = no; then
+ binconfigs=
+ AC_MSG_NOTICE([[libpng-config scripts will not be built]])
+ else
+ binconfigs='${binconfigs}'
+ fi],
+ [binconfigs='${binconfigs}'])
+AC_SUBST([binconfigs])
+
+# Support for prefixes to the API function names; this will generate defines
+# at the start of the build to rename exported library functions
+AC_ARG_WITH(libpng-prefix,
+ AS_HELP_STRING([[[--with-libpng-prefix]]],
+ [prefix libpng exported function (API) names with the given value]),
+ [if test "${withval:-no}" != "no"; then
+ AC_SUBST([PNG_PREFIX], [${withval}])
+ fi])
+AM_CONDITIONAL([DO_PNG_PREFIX], [test "${with_libpng_prefix:-no}" != "no"])
+
+# Control over what links are made for installed files. Versioned files are
+# always installed, when the following options are turned on corresponding
+# unversioned links are also created (normally as symbolic links):
+AC_ARG_ENABLE([unversioned-links],
+ AS_HELP_STRING([[[--enable-unversioned-links]]],
+ [Installed libpng header files are placed in a versioned subdirectory]
+ [and installed libpng library (including DLL) files are versioned.]
+ [If this option is enabled unversioned links will be created pointing to]
+ [the corresponding installed files. If you use libpng.pc or]
+ [libpng-config for all builds you do not need these links, but if you]
+ [compile programs directly they will typically #include <png.h> and]
+ [link with -lpng; in that case you need the links.]
+ [The links can be installed manually using 'make install-header-links']
+ [and 'make install-library-links' and can be removed using the]
+ [corresponding uninstall- targets. If you do enable this option every]
+ [libpng 'make install' will recreate the links to point to the just]
+ [installed version of libpng. The default is to create the links;]
+ [use --disable-unversioned-links to change this]))
+
+# The AM_CONDITIONAL test is written so that the default is enabled;
+# --disable-unversioned-links must be given to turn the option off.
+AM_CONDITIONAL([DO_INSTALL_LINKS],[test "$enable_unversioned_links" != "no"])
+
+AC_ARG_ENABLE([unversioned-libpng-pc],
+ AS_HELP_STRING([[[--enable-unversioned-libpng-pc]]],
+ [Install the configuration file 'libpng.pc' as a link to the versioned]
+ [version. This is done by default - use --disable-unversioned-libpng-pc]
+ [to change this.]))
+AM_CONDITIONAL([DO_INSTALL_LIBPNG_PC],
+ [test "$enable_unversioned_libpng_pc" != "no"])
+
+AC_ARG_ENABLE([unversioned-libpng-config],
+ AS_HELP_STRING([[[--enable-unversioned-libpng-config]]],
+ [Install the configuration file 'libpng-config' as a link to the]
+ [versioned version. This is done by default - use]
+ [--disable-unversioned-libpng-config to change this.]))
+AM_CONDITIONAL([DO_INSTALL_LIBPNG_CONFIG],
+ [test "$enable_unversioned_libpng_config" != "no"])
+
+# HOST SPECIFIC OPTIONS
+# =====================
+#
+# ARM
+# ===
+#
+# ARM NEON (SIMD) support.
+
+AC_ARG_ENABLE([arm-neon],
+ AS_HELP_STRING([[[--enable-arm-neon]]],
+ [Enable ARM NEON optimizations: =no/off, check, api, yes/on:]
+ [no/off: disable the optimizations; check: use internal checking code]
+ [(deprecated and poorly supported); api: disable by default, enable by]
+ [a call to png_set_option; yes/on: turn on unconditionally.]
+ [If not specified: determined by the compiler.]),
+ [case "$enableval" in
+ no|off)
+ # disable the default enabling on __ARM_NEON__ systems:
+ AC_DEFINE([PNG_ARM_NEON_OPT], [0],
+ [Disable ARM Neon optimizations])
+ # Prevent inclusion of the assembler files below:
+ enable_arm_neon=no;;
+ check)
+ AC_DEFINE([PNG_ARM_NEON_CHECK_SUPPORTED], [],
+ [Check for ARM Neon support at run-time]);;
+ api)
+ AC_DEFINE([PNG_ARM_NEON_API_SUPPORTED], [],
+ [Turn on ARM Neon optimizations at run-time]);;
+ yes|on)
+ AC_DEFINE([PNG_ARM_NEON_OPT], [2],
+ [Enable ARM Neon optimizations])
+ AC_MSG_WARN([--enable-arm-neon: please specify 'check' or 'api', if]
+ [you want the optimizations unconditionally pass -mfpu=neon]
+ [to the compiler.]);;
+ *)
+ AC_MSG_ERROR([--enable-arm-neon=${enable_arm_neon}: invalid value])
+ esac])
+
+# Add ARM specific files to all builds where the host_cpu is arm ('arm*') or
+# where ARM optimizations were explicitly requested (this allows a fallback if a
+# future host CPU does not match 'arm*')
+
+AM_CONDITIONAL([PNG_ARM_NEON],
+ [test "$enable_arm_neon" != 'no' &&
+ case "$host_cpu" in
+ arm*|aarch64*) :;;
+ *) test "$enable_arm_neon" != '';;
+ esac])
+
+AC_MSG_NOTICE([[Extra options for compiler: $PNG_COPTS]])
+
+# Config files, substituting as above
+AC_CONFIG_FILES([Makefile libpng.pc:libpng.pc.in])
+AC_CONFIG_FILES([libpng-config:libpng-config.in],
+ [chmod +x libpng-config])
+
+AC_OUTPUT
diff --git a/libpng/contrib/README.txt b/libpng/contrib/README.txt
new file mode 100644
index 0000000..97963c6
--- /dev/null
+++ b/libpng/contrib/README.txt
@@ -0,0 +1,5 @@
+
+This "contrib" directory contains contributions which are not necessarily under
+the libpng license, although all are open source. They are not part of
+libpng proper and are not used for building the library, although some are used
+for testing the library via "make check".
diff --git a/libpng/contrib/arm-neon/README b/libpng/contrib/arm-neon/README
new file mode 100644
index 0000000..b4248cf
--- /dev/null
+++ b/libpng/contrib/arm-neon/README
@@ -0,0 +1,83 @@
+OPERATING SYSTEM SPECIFIC ARM NEON DETECTION
+--------------------------------------------
+
+Detection of the ability to execute ARM NEON on an ARM processor requires
+operating system support. (The information is not available in user mode.)
+
+HOW TO USE THIS
+---------------
+
+This directory contains C code fragments that can be included in arm/arm_init.c
+by setting the macro PNG_ARM_NEON_FILE to the file name in "" or <> at build
+time. This setting is not recorded in pnglibconf.h and can be changed simply by
+rebuilding arm/arm_init.o with the required macro definition.
+
+For any of this code to be used the ARM NEON code must be enabled and run time
+checks must be supported. I.e.:
+
+#if PNG_ARM_NEON_OPT > 0
+#ifdef PNG_ARM_NEON_CHECK_SUPPORTED
+
+This is done in a 'configure' build by passing configure the argument:
+
+ --enable-arm-neon=check
+
+Apart from the basic Linux implementation in contrib/arm-neon/linux.c this code
+is unsupported. That means that it is not even compiled on a regular basis and
+may be broken in any given minor release.
+
+FILE FORMAT
+-----------
+
+Each file documents its testing status as of the last time it was tested (which
+may have been a long time ago):
+
+STATUS: one of:
+ SUPPORTED: This indicates that the file is included in the regularly
+ performed test builds and bugs are fixed when discovered.
+ COMPILED: This indicates that the code did compile at least once. See the
+ more detailed description for the extent to which the result was
+ successful.
+ TESTED: This means the code was fully compiled into the libpng test programs
+ and these were run at least once.
+
+BUG REPORTS: an email address to which to send reports of problems
+
+The file is a fragment of C code. It should not define any 'extern' symbols;
+everything should be static. It must define the function:
+
+static int png_have_neon(png_structp png_ptr);
+
+That function must return 1 if ARM NEON instructions are supported, 0 if not.
+It must not execute png_error unless it detects a bug. A png_error will prevent
+the reading of the PNG and in the future, writing too.
+
+BUG REPORTS
+-----------
+
+If you mail a bug report for any file that is not SUPPORTED there may only be
+limited response. Consider fixing it and sending a patch to fix the problem -
+this is more likely to result in action.
+
+CONTRIBUTIONS
+-------------
+
+You may send contributions of new implementations to
+png-mng-implement@sourceforge.net. Please write code in strict C90 C where
+possible. Obviously OS dependencies are to be expected. If you submit code you
+must have the authors permission and it must have a license that is acceptable
+to the current maintainer; in particular that license must permit modification
+and redistribution.
+
+Please try to make the contribution a single file and give the file a clear and
+unambiguous name that identifies the target OS. If multiple files really are
+required put them all in a sub-directory.
+
+You must also be prepared to handle bug reports from users of the code, either
+by joining the png-mng-implement mailing list or by providing an email for the
+"BUG REPORTS" entry or both. Please make sure that the header of the file
+contains the STATUS and BUG REPORTS fields as above.
+
+Please list the OS requirements as precisely as possible. Ideally you should
+also list the environment in which the code has been tested and certainly list
+any environments where you suspect it might not work.
diff --git a/libpng/contrib/arm-neon/android-ndk.c b/libpng/contrib/arm-neon/android-ndk.c
new file mode 100644
index 0000000..7240123
--- /dev/null
+++ b/libpng/contrib/arm-neon/android-ndk.c
@@ -0,0 +1,39 @@
+/* contrib/arm-neon/android-ndk.c
+ *
+ * Copyright (c) 2014 Glenn Randers-Pehrson
+ * Written by John Bowler, 2014.
+ * Last changed in libpng 1.6.10 [March 6, 2014]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * SEE contrib/arm-neon/README before reporting bugs
+ *
+ * STATUS: COMPILED, UNTESTED
+ * BUG REPORTS: png-mng-implement@sourceforge.net
+ *
+ * png_have_neon implemented for the Android NDK, see:
+ *
+ * Documentation:
+ * http://www.kandroid.org/ndk/docs/CPU-ARM-NEON.html
+ * http://code.google.com/p/android/issues/detail?id=49065
+ *
+ * NOTE: this requires that libpng is built against the Android NDK and linked
+ * with an implementation of the Android ARM 'cpu-features' library. The code
+ * has been compiled only, not linked: no version of the library has been found,
+ * only the header files exist in the NDK.
+ */
+#include <cpu-features.h>
+
+static int
+png_have_neon(png_structp png_ptr)
+{
+ /* This is a whole lot easier than the linux code, however it is probably
+ * implemented as below, therefore it is better to cache the result (these
+ * function calls may be slow!)
+ */
+ PNG_UNUSED(png_ptr)
+ return android_getCpuFamily() == ANDROID_CPU_FAMILY_ARM &&
+ (android_getCpuFeatures() & ANDROID_CPU_ARM_FEATURE_NEON) != 0;
+}
diff --git a/libpng/contrib/arm-neon/linux-auxv.c b/libpng/contrib/arm-neon/linux-auxv.c
new file mode 100644
index 0000000..4d26bd3
--- /dev/null
+++ b/libpng/contrib/arm-neon/linux-auxv.c
@@ -0,0 +1,120 @@
+/* contrib/arm-neon/linux-auxv.c
+ *
+ * Copyright (c) 2014 Glenn Randers-Pehrson
+ * Written by Mans Rullgard, 2011.
+ * Last changed in libpng 1.6.10 [March 6, 2014]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * SEE contrib/arm-neon/README before reporting bugs
+ *
+ * STATUS: COMPILED, TESTED
+ * BUG REPORTS: png-mng-implement@sourceforge.net
+ *
+ * png_have_neon implemented for Linux versions which allow access to
+ * /proc/self/auxv. This is probably faster, cleaner and safer than the code to
+ * read /proc/cpuinfo in contrib/arm-neon/linux, however it is yet another piece
+ * of potentially untested code and has more complex dependencies than the code
+ * to read cpuinfo.
+ *
+ * This generic __linux__ implementation requires reading /proc/self/auxv and
+ * looking at each element for one that records NEON capabilities.
+ */
+#include <unistd.h> /* for POSIX 1003.1 */
+#include <errno.h> /* for EINTR */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <elf.h>
+#include <asm/hwcap.h>
+
+/* A read call may be interrupted, in which case it returns -1 and sets errno to
+ * EINTR if nothing was done, otherwise (if something was done) a partial read
+ * may result.
+ */
+static size_t
+safe_read(png_structp png_ptr, int fd, void *buffer_in, size_t nbytes)
+{
+ size_t ntotal = 0;
+ char *buffer = png_voidcast(char*, buffer_in);
+
+ while (nbytes > 0)
+ {
+ unsigned int nread;
+ int iread;
+
+ /* Passing nread > INT_MAX to read is implementation defined in POSIX
+ * 1003.1, therefore despite the unsigned argument portable code must
+ * limit the value to INT_MAX!
+ */
+ if (nbytes > INT_MAX)
+ nread = INT_MAX;
+
+ else
+ nread = (unsigned int)/*SAFE*/nbytes;
+
+ iread = read(fd, buffer, nread);
+
+ if (iread == -1)
+ {
+ /* This is the devil in the details, a read can terminate early with 0
+ * bytes read because of EINTR, yet it still returns -1 otherwise end
+ * of file cannot be distinguished.
+ */
+ if (errno != EINTR)
+ {
+ png_warning(png_ptr, "/proc read failed");
+ return 0; /* I.e., a permanent failure */
+ }
+ }
+
+ else if (iread < 0)
+ {
+ /* Not a valid 'read' result: */
+ png_warning(png_ptr, "OS /proc read bug");
+ return 0;
+ }
+
+ else if (iread > 0)
+ {
+ /* Continue reading until a permanent failure, or EOF */
+ buffer += iread;
+ nbytes -= (unsigned int)/*SAFE*/iread;
+ ntotal += (unsigned int)/*SAFE*/iread;
+ }
+
+ else
+ return ntotal;
+ }
+
+ return ntotal; /* nbytes == 0 */
+}
+
+static int
+png_have_neon(png_structp png_ptr)
+{
+ int fd = open("/proc/self/auxv", O_RDONLY);
+ Elf32_auxv_t aux;
+
+ /* Failsafe: failure to open means no NEON */
+ if (fd == -1)
+ {
+ png_warning(png_ptr, "/proc/self/auxv open failed");
+ return 0;
+ }
+
+ while (safe_read(png_ptr, fd, &aux, sizeof aux) == sizeof aux)
+ {
+ if (aux.a_type == AT_HWCAP && (aux.a_un.a_val & HWCAP_NEON) != 0)
+ {
+ close(fd);
+ return 1;
+ }
+ }
+
+ close(fd);
+ return 0;
+}
diff --git a/libpng/contrib/arm-neon/linux.c b/libpng/contrib/arm-neon/linux.c
new file mode 100644
index 0000000..94f9bb1
--- /dev/null
+++ b/libpng/contrib/arm-neon/linux.c
@@ -0,0 +1,161 @@
+/* contrib/arm-neon/linux.c
+ *
+ * Copyright (c) 2014 Glenn Randers-Pehrson
+ * Written by John Bowler, 2014.
+ * Last changed in libpng 1.6.16 [December 22, 2014]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * SEE contrib/arm-neon/README before reporting bugs
+ *
+ * STATUS: SUPPORTED
+ * BUG REPORTS: png-mng-implement@sourceforge.net
+ *
+ * png_have_neon implemented for Linux by reading the widely available
+ * pseudo-file /proc/cpuinfo.
+ *
+ * This code is strict ANSI-C and is probably moderately portable; it does
+ * however use <stdio.h> and it assumes that /proc/cpuinfo is never localized.
+ */
+#include <stdio.h>
+
+static int
+png_have_neon(png_structp png_ptr)
+{
+ FILE *f = fopen("/proc/cpuinfo", "rb");
+
+ if (f != NULL)
+ {
+ /* This is a simple state machine which reads the input byte-by-byte until
+ * it gets a match on the 'neon' feature or reaches the end of the stream.
+ */
+ static const char ch_feature[] = { 70, 69, 65, 84, 85, 82, 69, 83 };
+ static const char ch_neon[] = { 78, 69, 79, 78 };
+
+ enum
+ {
+ StartLine, Feature, Colon, StartTag, Neon, HaveNeon, SkipTag, SkipLine
+ } state;
+ int counter;
+
+ for (state=StartLine, counter=0;;)
+ {
+ int ch = fgetc(f);
+
+ if (ch == EOF)
+ {
+ /* EOF means error or end-of-file, return false; neon at EOF is
+ * assumed to be a mistake.
+ */
+ fclose(f);
+ return 0;
+ }
+
+ switch (state)
+ {
+ case StartLine:
+ /* Match spaces at the start of line */
+ if (ch <= 32) /* skip control characters and space */
+ break;
+
+ counter=0;
+ state = Feature;
+ /* FALL THROUGH */
+
+ case Feature:
+ /* Match 'FEATURE', ASCII case insensitive. */
+ if ((ch & ~0x20) == ch_feature[counter])
+ {
+ if (++counter == (sizeof ch_feature))
+ state = Colon;
+ break;
+ }
+
+ /* did not match 'feature' */
+ state = SkipLine;
+ /* FALL THROUGH */
+
+ case SkipLine:
+ skipLine:
+ /* Skip everything until we see linefeed or carriage return */
+ if (ch != 10 && ch != 13)
+ break;
+
+ state = StartLine;
+ break;
+
+ case Colon:
+ /* Match any number of space or tab followed by ':' */
+ if (ch == 32 || ch == 9)
+ break;
+
+ if (ch == 58) /* i.e. ':' */
+ {
+ state = StartTag;
+ break;
+ }
+
+ /* Either a bad line format or a 'feature' prefix followed by
+ * other characters.
+ */
+ state = SkipLine;
+ goto skipLine;
+
+ case StartTag:
+ /* Skip space characters before a tag */
+ if (ch == 32 || ch == 9)
+ break;
+
+ state = Neon;
+ counter = 0;
+ /* FALL THROUGH */
+
+ case Neon:
+ /* Look for 'neon' tag */
+ if ((ch & ~0x20) == ch_neon[counter])
+ {
+ if (++counter == (sizeof ch_neon))
+ state = HaveNeon;
+ break;
+ }
+
+ state = SkipTag;
+ /* FALL THROUGH */
+
+ case SkipTag:
+ /* Skip non-space characters */
+ if (ch == 10 || ch == 13)
+ state = StartLine;
+
+ else if (ch == 32 || ch == 9)
+ state = StartTag;
+ break;
+
+ case HaveNeon:
+ /* Have seen a 'neon' prefix, but there must be a space or new
+ * line character to terminate it.
+ */
+ if (ch == 10 || ch == 13 || ch == 32 || ch == 9)
+ {
+ fclose(f);
+ return 1;
+ }
+
+ state = SkipTag;
+ break;
+
+ default:
+ png_error(png_ptr, "png_have_neon: internal error (bug)");
+ }
+ }
+ }
+
+#ifdef PNG_WARNINGS_SUPPORTED
+ else
+ png_warning(png_ptr, "/proc/cpuinfo open failed");
+#endif
+
+ return 0;
+}
diff --git a/libpng/contrib/conftest/README b/libpng/contrib/conftest/README
new file mode 100644
index 0000000..0f47279
--- /dev/null
+++ b/libpng/contrib/conftest/README
@@ -0,0 +1,49 @@
+This directory contains test configuration files, currently always '.dfa' files
+intended to be used in the build by setting the make macro DFA_XTRA to the name
+of the file.
+
+These files are used in release validation of the 'configure' builds of libpng
+by building 'make check', or 'make all-am' for cross-builds, with each .dfa
+file.
+
+The files in this directory may change between minor releases, however
+contributions describing specific builds of libpng are welcomed. There is no
+guarantee that libpng will continue to build with such configurations; support
+for given configurations can be, and has been, dropped between successive minor
+releases. However if a .dfa file describing a configuration is not in this
+directory it is very unlikely that it will be tested before a minor release!
+
+You can use these .dfa files as the basis of new configurations. Files in this
+directory should not have any use restrictions or restrictive licenses.
+
+This directory is not included in the .zip and .7z distributions, which do
+not contain 'configure' scripts.
+
+DOCUMENTATION
+=============
+
+Examples:
+ ${srcdir}/pngusr.dfa
+ ${srcdir}/contrib/pngminim/*/pngusr.dfa
+
+Documentation of the options:
+ ${srcdir}/scripts/pnglibconf.dfa
+
+Documentation of the file format:
+ ${srcdir}/scripts/options.awk
+
+FILE NAMING
+===========
+
+File names in this directory may NOT contain any of the five characters:
+
+ - , + * ?
+
+Neither may they contain any space character.
+
+While other characters may be used it is strongly suggested that file names be
+limited to lower case Latiin alphabetic characters (a-z), digits (0-9) and, if
+necessary the underscore (_) character. File names should be about 8 characters
+long (excluding the .dfa extension). Submitted .dfa files should have names
+between 7 and 16 characters long, shorter names (6 characters or less) are
+reserved for standard tests.
diff --git a/libpng/contrib/conftest/read.dfa b/libpng/contrib/conftest/read.dfa
new file mode 100644
index 0000000..21e88d0
--- /dev/null
+++ b/libpng/contrib/conftest/read.dfa
@@ -0,0 +1,58 @@
+# read.dfa
+# Build time configuration of libpng
+#
+# Author: John Bowler
+# Copyright: (c) John Bowler, 2013
+# Usage rights:
+# To the extent possible under law, the author has waived all copyright and
+# related or neighboring rights to this work. This work is published from:
+# United States.
+#
+# Build libpng with basic read support. This enables the lowest level libpng
+# read API - the one where the calling code has to use a loop to read each row.
+# At present this is the API used by most programs.
+#
+# Support is enabled only for those chunks and transformations that are
+# typically required - others can be added easily.
+#
+
+everything = off
+
+# The sequential read code is enabled here; the progressive code can be used
+# instead but there is no point enabling both.
+
+option SEQUENTIAL_READ on
+
+# Likewise it is pointless enabling both fixed and floating point APIs. Choose
+# one or the other for both the API and the internal math.
+
+#Fixed point:
+#option FIXED_POINT on
+#option FLOATING_ARITHMETIC off
+
+#Floating point:
+option FLOATING_POINT on
+option FLOATING_ARITHMETIC on
+
+# Basic error handling, IO and user memory support. The latter allows the
+# application program to provide its own implementations of 'malloc' and 'free'.
+option SETJMP on
+option STDIO on
+option USER_MEM on
+
+# To read the full set of PNG images correctly interlace, transparency and
+# 16-bit support is required. The application can implement interlace itself,
+# but very few do and it's no longer possible to disable it when READ is
+# enabled.
+option READ_tRNS on
+option READ_16BIT on
+
+# Everything else is application dependent. This file assumes the app handles
+# all the native PNG bit layouts, so it doesn't need any of layout change
+# transforms, but needs libpng to perform gamma correction. It doesn't do any
+# colorspace stuff and ignores the 'significant bit' information.
+#
+# If your app always expands the image to a limited set of bit layouts you
+# probably want to consider using the simplified API instead of the low level
+# one - see png.h and s_read.dfa.
+option READ_GAMMA on
diff --git a/libpng/contrib/conftest/s_read.dfa b/libpng/contrib/conftest/s_read.dfa
new file mode 100644
index 0000000..cb1ce0b
--- /dev/null
+++ b/libpng/contrib/conftest/s_read.dfa
@@ -0,0 +1,35 @@
+# s_read.dfa
+# Build time configuration of libpng
+#
+# Author: John Bowler
+# Copyright: (c) John Bowler, 2013
+# Usage rights:
+# To the extent possible under law, the author has waived all copyright and
+# related or neighboring rights to this work. This work is published from:
+# United States.
+#
+# Build libpng with simplified read support (only). This builds a minimal
+# libpng able to read all PNG formats and convert them into a small number of
+# well understood memory formats.
+#
+
+everything = off
+
+option SIMPLIFIED_READ on
+
+# It isn't necessary to chose fixed or floating point for the APIs because the
+# simplified API doesn't need fixed or floating point numbers. It is necessary
+# to chose an internal math implementation. The default (because of 'everything
+# = off') is fixed point - turn the floating point implementation on if you have
+# hardware floating point or prefer your software floating point implementation.
+option FLOATING_ARITHMETIC on
+
+# This is not strictly necessary, but without it the message strings in the API
+# will not be filled in
+option ERROR_TEXT on
+
+# Switching these options on enables the 'AFIRST' and 'BGR' formats - you don't
+# need this if you don't use them, they just allow the in-memory layout to be
+# changed to match common hardware formats.
+option SIMPLIFIED_READ_AFIRST on
+option SIMPLIFIED_READ_BGR on
diff --git a/libpng/contrib/conftest/s_write.dfa b/libpng/contrib/conftest/s_write.dfa
new file mode 100644
index 0000000..e540a46
--- /dev/null
+++ b/libpng/contrib/conftest/s_write.dfa
@@ -0,0 +1,33 @@
+# s_write.dfa
+# Build time configuration of libpng
+#
+# Author: John Bowler
+# Copyright: (c) John Bowler, 2013
+# Usage rights:
+# To the extent possible under law, the author has waived all copyright and
+# related or neighboring rights to this work. This work is published from:
+# United States.
+#
+# Build libpng with (just) simplified write support
+#
+
+everything = off
+
+option SIMPLIFIED_WRITE on
+
+# It isn't necessary to chose fixed or floating point for the APIs because the
+# simplified API doesn't need fixed or floating point numbers. It is necessary
+# to chose an internal math implementation. The default (because of 'everything
+# = off') is fixed point - turn the floating point implementation on if you have
+# hardware floating point or prefer your software floating point implementation.
+option FLOATING_ARITHMETIC on
+
+# This is not strictly necessary, but without it the message strings in the API
+# will not be filled in
+option ERROR_TEXT on
+
+# Switching these options on enables the 'AFIRST' and 'BGR' formats - you don't
+# need this if you don't use them, they just allow the in-memory layout to be
+# changed to match common hardware formats.
+option SIMPLIFIED_WRITE_AFIRST on
+option SIMPLIFIED_WRITE_BGR on
diff --git a/libpng/contrib/conftest/simple.dfa b/libpng/contrib/conftest/simple.dfa
new file mode 100644
index 0000000..0419333
--- /dev/null
+++ b/libpng/contrib/conftest/simple.dfa
@@ -0,0 +1,36 @@
+# simple.dfa
+# Build time configuration of libpng
+#
+# Author: John Bowler
+# Copyright: (c) John Bowler, 2013
+# Usage rights:
+# To the extent possible under law, the author has waived all copyright and
+# related or neighboring rights to this work. This work is published from:
+# United States.
+#
+# Build libpng with just the simplified APIs (read and write).
+#
+
+everything = off
+
+option SIMPLIFIED_WRITE on
+option SIMPLIFIED_READ on
+
+# It isn't necessary to chose fixed or floating point for the APIs because the
+# simplified API doesn't need fixed or floating point numbers. It is necessary
+# to chose an internal math implementation. The default (because of 'everything
+# = off') is fixed point - turn the floating point implementation on if you have
+# hardware floating point or prefer your software floating point implementation.
+option FLOATING_ARITHMETIC on
+
+# This is not strictly necessary, but without it the message strings in the API
+# will not be filled in
+option ERROR_TEXT on
+
+# Switching these options on enables the 'AFIRST' and 'BGR' formats - you don't
+# need this if you don't use them, they just allow the in-memory layout to be
+# changed to match common hardware formats.
+option SIMPLIFIED_READ_AFIRST on
+option SIMPLIFIED_READ_BGR on
+option SIMPLIFIED_WRITE_AFIRST on
+option SIMPLIFIED_WRITE_BGR on
diff --git a/libpng/contrib/conftest/write.dfa b/libpng/contrib/conftest/write.dfa
new file mode 100644
index 0000000..3319aab
--- /dev/null
+++ b/libpng/contrib/conftest/write.dfa
@@ -0,0 +1,45 @@
+# write.dfa
+# Build time configuration of libpng
+#
+# Author: John Bowler
+# Copyright: (c) John Bowler, 2013
+# Usage rights:
+# To the extent possible under law, the author has waived all copyright and
+# related or neighboring rights to this work. This work is published from:
+# United States.
+#
+# Build libpng with no read support and minimal write support.
+#
+
+everything = off
+
+# Switch on the write code - this makes a minimalist encoder
+
+option WRITE on
+
+# Choose fixed or floating point APIs and arithmetic. The choices are
+# independent but normally they will match. It is typically better to use the
+# floating point if you have floating point hardware. If you don't know, or
+# (perhaps) to make libpng smaller used fixed point throughout.
+
+#Fixed point:
+#option FIXED_POINT on
+#option FLOATING_ARITHMETIC off
+
+#Floating point:
+option FLOATING_POINT on
+option FLOATING_ARITHMETIC on
+
+# Basic error handling, IO and user memory support. The latter allows the
+# application program to provide its own implementations of 'malloc' and 'free'.
+option SETJMP on
+option STDIO on
+option USER_MEM on
+
+# Everything else is optional. Unlike the read code in libpng the write code
+# does not need to deal with arbitrary formats, so only add support for things
+# you really do write! For example you might only write sRGB images, sometimes
+# with transparency and never write 16 bit images, so:
+option WRITE_sRGB on
+option WRITE_tRNS on
+#option WRITE_16BIT off (this is the default with 'everything = off')
diff --git a/libpng/contrib/examples/README.txt b/libpng/contrib/examples/README.txt
new file mode 100644
index 0000000..0525c9d
--- /dev/null
+++ b/libpng/contrib/examples/README.txt
@@ -0,0 +1,24 @@
+
+This directory (contrib/examples) contains examples of libpng usage.
+
+NO COPYRIGHT RIGHTS ARE CLAIMED TO ANY OF THE FILES IN THIS DIRECTORY.
+
+To the extent possible under law, the authors have waived all copyright and
+related or neighboring rights to this work. This work is published from:
+United States.
+
+The files may be used freely in any way. The intention is that appropriate
+parts of the files be used in other libpng-using programs without any need for
+the authors of the using code to seek copyright or license from the original
+authors.
+
+The source code and comments in this directory are the original work of the
+people named below. No other person or organization has made contributions to
+the work in this directory.
+
+ORIGINAL AUTHORS
+ The following people have contributed to the code in this directory. None
+ of the people below claim any rights with regard to the contents of this
+ directory.
+
+ John Bowler <jbowler@acm.org>
diff --git a/libpng/contrib/examples/iccfrompng.c b/libpng/contrib/examples/iccfrompng.c
new file mode 100644
index 0000000..603037e
--- /dev/null
+++ b/libpng/contrib/examples/iccfrompng.c
@@ -0,0 +1,185 @@
+/*- iccfrompng
+ *
+ * COPYRIGHT: Written by John Cunningham Bowler, 2011.
+ * To the extent possible under law, the author has waived all copyright and
+ * related or neighboring rights to this work. This work is published from:
+ * United States.
+ *
+ * Extract any icc profiles found in the given PNG files. This is a simple
+ * example of a program that extracts information from the header of a PNG file
+ * without processing the image. Notice that some header information may occur
+ * after the image data. Textual data and comments are an example; the approach
+ * in this file won't work reliably for such data because it only looks for the
+ * information in the section of the file that preceeds the image data.
+ *
+ * Compile and link against libpng and zlib, plus anything else required on the
+ * system you use.
+ *
+ * To use supply a list of PNG files containing iCCP chunks, the chunks will be
+ * extracted to a similarly named file with the extension replaced by 'icc',
+ * which will be overwritten without warning.
+ */
+#include <stdlib.h>
+#include <setjmp.h>
+#include <string.h>
+#include <stdio.h>
+
+#include <png.h>
+
+#if defined(PNG_READ_SUPPORTED) && defined(PNG_STDIO_SUPPORTED) && \
+ defined (PNG_iCCP_SUPPORTED)
+
+
+static int verbose = 1;
+static png_byte no_profile[] = "no profile";
+
+static png_bytep
+extract(FILE *fp, png_uint_32 *proflen)
+{
+ png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,0);
+ png_infop info_ptr = NULL;
+ png_bytep result = NULL;
+
+ /* Initialize for error or no profile: */
+ *proflen = 0;
+
+ if (png_ptr == NULL)
+ {
+ fprintf(stderr, "iccfrompng: version library mismatch?\n");
+ return 0;
+ }
+
+ if (setjmp(png_jmpbuf(png_ptr)))
+ {
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ return 0;
+ }
+
+ png_init_io(png_ptr, fp);
+
+ info_ptr = png_create_info_struct(png_ptr);
+ if (info_ptr == NULL)
+ png_error(png_ptr, "OOM allocating info structure");
+
+ png_read_info(png_ptr, info_ptr);
+
+ {
+ png_charp name;
+ int compression_type;
+ png_bytep profile;
+
+ if (png_get_iCCP(png_ptr, info_ptr, &name, &compression_type, &profile,
+ proflen) & PNG_INFO_iCCP)
+ {
+ result = malloc(*proflen);
+ if (result != NULL)
+ memcpy(result, profile, *proflen);
+
+ else
+ png_error(png_ptr, "OOM allocating profile buffer");
+ }
+
+ else
+ result = no_profile;
+ }
+
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ return result;
+}
+
+static int
+extract_one_file(const char *filename)
+{
+ int result = 0;
+ FILE *fp = fopen(filename, "rb");
+
+ if (fp != NULL)
+ {
+ png_uint_32 proflen = 0;
+ png_bytep profile = extract(fp, &proflen);
+
+ if (profile != NULL && profile != no_profile)
+ {
+ size_t len;
+ char *output;
+
+ {
+ const char *ep = strrchr(filename, '.');
+
+ if (ep != NULL)
+ len = ep-filename;
+
+ else
+ len = strlen(filename);
+ }
+
+ output = malloc(len + 5);
+ if (output != NULL)
+ {
+ FILE *of;
+
+ memcpy(output, filename, len);
+ strcpy(output+len, ".icc");
+
+ of = fopen(output, "wb");
+ if (of != NULL)
+ {
+ if (fwrite(profile, proflen, 1, of) == 1 &&
+ fflush(of) == 0 &&
+ fclose(of) == 0)
+ {
+ if (verbose)
+ printf("%s -> %s\n", filename, output);
+ /* Success return */
+ result = 1;
+ }
+
+ else
+ {
+ fprintf(stderr, "%s: error writing profile\n", output);
+ if (remove(output))
+ fprintf(stderr, "%s: could not remove file\n", output);
+ }
+ }
+
+ else
+ fprintf(stderr, "%s: failed to open output file\n", output);
+
+ free(output);
+ }
+
+ else
+ fprintf(stderr, "%s: OOM allocating string!\n", filename);
+
+ free(profile);
+ }
+
+ else if (verbose && profile == no_profile)
+ printf("%s has no profile\n", filename);
+ }
+
+ else
+ fprintf(stderr, "%s: could not open file\n", filename);
+
+ return result;
+}
+
+int
+main(int argc, char **argv)
+{
+ int i;
+ int extracted = 0;
+
+ for (i=1; i<argc; ++i)
+ {
+ if (strcmp(argv[i], "-q") == 0)
+ verbose = 0;
+
+ else if (extract_one_file(argv[i]))
+ extracted = 1;
+ }
+
+ /* Exit code is true if any extract succeeds */
+ return extracted == 0;
+}
+#endif /* READ && STDIO && iCCP */
diff --git a/libpng/contrib/examples/pngpixel.c b/libpng/contrib/examples/pngpixel.c
new file mode 100644
index 0000000..f762379
--- /dev/null
+++ b/libpng/contrib/examples/pngpixel.c
@@ -0,0 +1,371 @@
+/*- pngpixel
+ *
+ * COPYRIGHT: Written by John Cunningham Bowler, 2011.
+ * To the extent possible under law, the author has waived all copyright and
+ * related or neighboring rights to this work. This work is published from:
+ * United States.
+ *
+ * Read a single pixel value from a PNG file.
+ *
+ * This code illustrates basic 'by-row' reading of a PNG file using libpng.
+ * Rows are read until a particular pixel is found; the value of this pixel is
+ * then printed on stdout.
+ *
+ * The code illustrates how to do this on interlaced as well as non-interlaced
+ * images. Normally you would call png_set_interlace_handling() to have libpng
+ * deal with the interlace for you, but that obliges you to buffer half of the
+ * image to assemble the interlaced rows. In this code
+ * png_set_interlace_handling() is not called and, instead, the code handles the
+ * interlace passes directly looking for the required pixel.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <setjmp.h> /* required for error handling */
+
+/* Normally use <png.h> here to get the installed libpng, but this is done to
+ * ensure the code picks up the local libpng implementation:
+ */
+#include "../../png.h"
+
+#if defined(PNG_READ_SUPPORTED) && defined(PNG_SEQUENTIAL_READ_SUPPORTED)
+
+/* Return component 'c' of pixel 'x' from the given row. */
+static unsigned int
+component(png_const_bytep row, png_uint_32 x, unsigned int c,
+ unsigned int bit_depth, unsigned int channels)
+{
+ /* PNG images can be up to 2^31 pixels wide, but this means they can be up to
+ * 2^37 bits wide (for a 64-bit pixel - the largest possible) and hence 2^34
+ * bytes wide. Since the row fitted into memory, however, the following must
+ * work:
+ */
+ png_uint_32 bit_offset_hi = bit_depth * ((x >> 6) * channels);
+ png_uint_32 bit_offset_lo = bit_depth * ((x & 0x3f) * channels + c);
+
+ row = (png_const_bytep)(((PNG_CONST png_byte (*)[8])row) + bit_offset_hi);
+ row += bit_offset_lo >> 3;
+ bit_offset_lo &= 0x07;
+
+ /* PNG pixels are packed into bytes to put the first pixel in the highest
+ * bits of the byte and into two bytes for 16-bit values with the high 8 bits
+ * first, so:
+ */
+ switch (bit_depth)
+ {
+ case 1: return (row[0] >> (7-bit_offset_lo)) & 0x01;
+ case 2: return (row[0] >> (6-bit_offset_lo)) & 0x03;
+ case 4: return (row[0] >> (4-bit_offset_lo)) & 0x0f;
+ case 8: return row[0];
+ case 16: return (row[0] << 8) + row[1];
+ default:
+ /* This should never happen; it indicates a bug in this program or in
+ * libpng itself:
+ */
+ fprintf(stderr, "pngpixel: invalid bit depth %u\n", bit_depth);
+ exit(1);
+ }
+}
+
+/* Print a pixel from a row returned by libpng; determine the row format, find
+ * the pixel, and print the relevant information to stdout.
+ */
+static void
+print_pixel(png_structp png_ptr, png_infop info_ptr, png_const_bytep row,
+ png_uint_32 x)
+{
+ PNG_CONST unsigned int bit_depth = png_get_bit_depth(png_ptr, info_ptr);
+
+ switch (png_get_color_type(png_ptr, info_ptr))
+ {
+ case PNG_COLOR_TYPE_GRAY:
+ printf("GRAY %u\n", component(row, x, 0, bit_depth, 1));
+ return;
+
+ /* The palette case is slightly more difficult - the palette and, if
+ * present, the tRNS ('transparency', though the values are really
+ * opacity) data must be read to give the full picture:
+ */
+ case PNG_COLOR_TYPE_PALETTE:
+ {
+ PNG_CONST int index = component(row, x, 0, bit_depth, 1);
+ png_colorp palette = NULL;
+ int num_palette = 0;
+
+ if ((png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette) &
+ PNG_INFO_PLTE) && num_palette > 0 && palette != NULL)
+ {
+ png_bytep trans_alpha = NULL;
+ int num_trans = 0;
+ if ((png_get_tRNS(png_ptr, info_ptr, &trans_alpha, &num_trans,
+ NULL) & PNG_INFO_tRNS) && num_trans > 0 &&
+ trans_alpha != NULL)
+ printf("INDEXED %u = %d %d %d %d\n", index,
+ palette[index].red, palette[index].green,
+ palette[index].blue,
+ index < num_trans ? trans_alpha[index] : 255);
+
+ else /* no transparency */
+ printf("INDEXED %u = %d %d %d\n", index,
+ palette[index].red, palette[index].green,
+ palette[index].blue);
+ }
+
+ else
+ printf("INDEXED %u = invalid index\n", index);
+ }
+ return;
+
+ case PNG_COLOR_TYPE_RGB:
+ printf("RGB %u %u %u\n", component(row, x, 0, bit_depth, 3),
+ component(row, x, 1, bit_depth, 3),
+ component(row, x, 2, bit_depth, 3));
+ return;
+
+ case PNG_COLOR_TYPE_GRAY_ALPHA:
+ printf("GRAY+ALPHA %u %u\n", component(row, x, 0, bit_depth, 2),
+ component(row, x, 1, bit_depth, 2));
+ return;
+
+ case PNG_COLOR_TYPE_RGB_ALPHA:
+ printf("RGBA %u %u %u %u\n", component(row, x, 0, bit_depth, 4),
+ component(row, x, 1, bit_depth, 4),
+ component(row, x, 2, bit_depth, 4),
+ component(row, x, 3, bit_depth, 4));
+ return;
+
+ default:
+ png_error(png_ptr, "pngpixel: invalid color type");
+ }
+}
+
+int main(int argc, const char **argv)
+{
+ /* This program uses the default, <setjmp.h> based, libpng error handling
+ * mechanism, therefore any local variable that exists before the call to
+ * setjmp and is changed after the call to setjmp returns successfully must
+ * be declared with 'volatile' to ensure that their values don't get
+ * destroyed by longjmp:
+ */
+ volatile int result = 1/*fail*/;
+
+ if (argc == 4)
+ {
+ long x = atol(argv[1]);
+ long y = atol(argv[2]);
+ FILE *f = fopen(argv[3], "rb");
+ volatile png_bytep row = NULL;
+
+ if (f != NULL)
+ {
+ /* libpng requires a callback function for handling errors; this
+ * callback must not return. The default callback function uses a
+ * stored <setjmp.h> style jmp_buf which is held in a png_struct and
+ * writes error messages to stderr. Creating the png_struct is a
+ * little tricky; just copy the following code.
+ */
+ png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
+ NULL, NULL, NULL);
+
+ if (png_ptr != NULL)
+ {
+ png_infop info_ptr = png_create_info_struct(png_ptr);
+
+ if (info_ptr != NULL)
+ {
+ /* Declare stack variables to hold pointers to locally allocated
+ * data.
+ */
+
+ /* Initialize the error control buffer: */
+ if (setjmp(png_jmpbuf(png_ptr)) == 0)
+ {
+ png_uint_32 width, height;
+ int bit_depth, color_type, interlace_method,
+ compression_method, filter_method;
+ png_bytep row_tmp;
+
+ /* Now associate the recently opened (FILE*) with the default
+ * libpng initialization functions. Sometimes libpng is
+ * compiled without stdio support (it can be difficult to do
+ * in some environments); in that case you will have to write
+ * your own read callback to read data from the (FILE*).
+ */
+ png_init_io(png_ptr, f);
+
+ /* And read the first part of the PNG file - the header and
+ * all the information up to the first pixel.
+ */
+ png_read_info(png_ptr, info_ptr);
+
+ /* This fills in enough information to tell us the width of
+ * each row in bytes, allocate the appropriate amount of
+ * space. In this case png_malloc is used - it will not
+ * return if memory isn't available.
+ */
+ row = png_malloc(png_ptr, png_get_rowbytes(png_ptr,
+ info_ptr));
+
+ /* To avoid the overhead of using a volatile auto copy row_tmp
+ * to a local here - just use row for the png_free below.
+ */
+ row_tmp = row;
+
+ /* All the information we need is in the header is returned by
+ * png_get_IHDR, if this fails we can now use 'png_error' to
+ * signal the error and return control to the setjmp above.
+ */
+ if (png_get_IHDR(png_ptr, info_ptr, &width, &height,
+ &bit_depth, &color_type, &interlace_method,
+ &compression_method, &filter_method))
+ {
+ int passes, pass;
+
+ /* png_set_interlace_handling returns the number of
+ * passes required as well as turning on libpng's
+ * handling, but since we do it ourselves this is
+ * necessary:
+ */
+ switch (interlace_method)
+ {
+ case PNG_INTERLACE_NONE:
+ passes = 1;
+ break;
+
+ case PNG_INTERLACE_ADAM7:
+ passes = PNG_INTERLACE_ADAM7_PASSES;
+ break;
+
+ default:
+ png_error(png_ptr, "pngpixel: unknown interlace");
+ }
+
+ /* Now read the pixels, pass-by-pass, row-by-row: */
+ png_start_read_image(png_ptr);
+
+ for (pass=0; pass<passes; ++pass)
+ {
+ png_uint_32 ystart, xstart, ystep, xstep;
+ png_uint_32 py;
+
+ if (interlace_method == PNG_INTERLACE_ADAM7)
+ {
+ /* Sometimes the whole pass is empty because the
+ * image is too narrow or too short. libpng
+ * expects to be called for each row that is
+ * present in the pass, so it may be necessary to
+ * skip the loop below (over py) if the image is
+ * too narrow.
+ */
+ if (PNG_PASS_COLS(width, pass) == 0)
+ continue;
+
+ /* We need the starting pixel and the offset
+ * between each pixel in this pass; use the macros
+ * in png.h:
+ */
+ xstart = PNG_PASS_START_COL(pass);
+ ystart = PNG_PASS_START_ROW(pass);
+ xstep = PNG_PASS_COL_OFFSET(pass);
+ ystep = PNG_PASS_ROW_OFFSET(pass);
+ }
+
+ else
+ {
+ ystart = xstart = 0;
+ ystep = xstep = 1;
+ }
+
+ /* To find the pixel, loop over 'py' for each pass
+ * reading a row and then checking to see if it
+ * contains the pixel.
+ */
+ for (py = ystart; py < height; py += ystep)
+ {
+ png_uint_32 px, ppx;
+
+ /* png_read_row takes two pointers. When libpng
+ * handles the interlace the first is filled in
+ * pixel-by-pixel, and the second receives the same
+ * pixels but they are replicated across the
+ * unwritten pixels so far for each pass. When we
+ * do the interlace, however, they just contain
+ * the pixels from the interlace pass - giving
+ * both is wasteful and pointless, so we pass a
+ * NULL pointer.
+ */
+ png_read_row(png_ptr, row_tmp, NULL);
+
+ /* Now find the pixel if it is in this row; there
+ * are, of course, much better ways of doing this
+ * than using a for loop:
+ */
+ if (y == py) for (px = xstart, ppx = 0;
+ px < width; px += xstep, ++ppx) if (x == px)
+ {
+ /* 'ppx' is the index of the pixel in the row
+ * buffer.
+ */
+ print_pixel(png_ptr, info_ptr, row_tmp, ppx);
+
+ /* Now terminate the loops early - we have
+ * found and handled the required data.
+ */
+ goto pass_loop_end;
+ } /* x loop */
+ } /* y loop */
+ } /* pass loop */
+
+ /* Finally free the temporary buffer: */
+ pass_loop_end:
+ row = NULL;
+ png_free(png_ptr, row_tmp);
+ }
+
+ else
+ png_error(png_ptr, "pngpixel: png_get_IHDR failed");
+
+ }
+
+ else
+ {
+ /* Else libpng has raised an error. An error message has
+ * already been output, so it is only necessary to clean up
+ * locally allocated data:
+ */
+ if (row != NULL)
+ {
+ /* The default implementation of png_free never errors out
+ * (it just crashes if something goes wrong), but the safe
+ * way of using it is still to clear 'row' before calling
+ * png_free:
+ */
+ png_bytep row_tmp = row;
+ row = NULL;
+ png_free(png_ptr, row_tmp);
+ }
+ }
+
+ png_destroy_info_struct(png_ptr, &info_ptr);
+ }
+
+ else
+ fprintf(stderr, "pngpixel: out of memory allocating png_info\n");
+
+ png_destroy_read_struct(&png_ptr, NULL, NULL);
+ }
+
+ else
+ fprintf(stderr, "pngpixel: out of memory allocating png_struct\n");
+ }
+
+ else
+ fprintf(stderr, "pngpixel: %s: could not open file\n", argv[3]);
+ }
+
+ else
+ /* Wrong number of arguments */
+ fprintf(stderr, "pngpixel: usage: pngpixel x y png-file\n");
+
+ return result;
+}
+#endif /* READ && SEQUENTIAL_READ */
diff --git a/libpng/contrib/examples/pngtopng.c b/libpng/contrib/examples/pngtopng.c
new file mode 100644
index 0000000..4acf6b3
--- /dev/null
+++ b/libpng/contrib/examples/pngtopng.c
@@ -0,0 +1,95 @@
+/*- pngtopng
+ *
+ * COPYRIGHT: Written by John Cunningham Bowler, 2011.
+ * To the extent possible under law, the author has waived all copyright and
+ * related or neighboring rights to this work. This work is published from:
+ * United States.
+ *
+ * Read a PNG and write it out in a fixed format, using the 'simplified API'
+ * that was introduced in libpng-1.6.0.
+ *
+ * This sample code is just the code from the top of 'example.c' with some error
+ * handling added. See example.c for more comments.
+ */
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+/* Normally use <png.h> here to get the installed libpng, but this is done to
+ * ensure the code picks up the local libpng implementation:
+ */
+#include "../../png.h"
+#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) && \
+ defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
+
+int main(int argc, const char **argv)
+{
+ int result = 1;
+
+ if (argc == 3)
+ {
+ png_image image;
+
+ /* Only the image structure version number needs to be set. */
+ memset(&image, 0, sizeof image);
+ image.version = PNG_IMAGE_VERSION;
+
+ if (png_image_begin_read_from_file(&image, argv[1]))
+ {
+ png_bytep buffer;
+
+ /* Change this to try different formats! If you set a colormap format
+ * then you must also supply a colormap below.
+ */
+ image.format = PNG_FORMAT_RGBA;
+
+ buffer = malloc(PNG_IMAGE_SIZE(image));
+
+ if (buffer != NULL)
+ {
+ if (png_image_finish_read(&image, NULL/*background*/, buffer,
+ 0/*row_stride*/, NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP */))
+ {
+ if (png_image_write_to_file(&image, argv[2],
+ 0/*convert_to_8bit*/, buffer, 0/*row_stride*/,
+ NULL/*colormap*/))
+ result = 0;
+
+ else
+ fprintf(stderr, "pngtopng: write %s: %s\n", argv[2],
+ image.message);
+
+ free(buffer);
+ }
+
+ else
+ {
+ fprintf(stderr, "pngtopng: read %s: %s\n", argv[1],
+ image.message);
+
+ /* This is the only place where a 'free' is required; libpng does
+ * the cleanup on error and success, but in this case we couldn't
+ * complete the read because of running out of memory.
+ */
+ png_image_free(&image);
+ }
+ }
+
+ else
+ fprintf(stderr, "pngtopng: out of memory: %lu bytes\n",
+ (unsigned long)PNG_IMAGE_SIZE(image));
+ }
+
+ else
+ /* Failed to read the first argument: */
+ fprintf(stderr, "pngtopng: %s: %s\n", argv[1], image.message);
+ }
+
+ else
+ /* Wrong number of arguments */
+ fprintf(stderr, "pngtopng: usage: pngtopng input-file output-file\n");
+
+ return result;
+}
+#endif /* READ && WRITE */
diff --git a/libpng/contrib/examples/simpleover.c b/libpng/contrib/examples/simpleover.c
new file mode 100644
index 0000000..59dd313
--- /dev/null
+++ b/libpng/contrib/examples/simpleover.c
@@ -0,0 +1,648 @@
+/*- simpleover
+ *
+ * COPYRIGHT: Written by John Cunningham Bowler, 2015.
+ * To the extent possible under law, the author has waived all copyright and
+ * related or neighboring rights to this work. This work is published from:
+ * United States.
+ *
+ * Read several PNG files, which should have an alpha channel or transparency
+ * information, and composite them together to produce one or more 16-bit linear
+ * RGBA intermediates. This involves doing the correct 'over' composition to
+ * combine the alpha channels and corresponding data.
+ *
+ * Finally read an output (background) PNG using the 24-bit RGB format (the
+ * PNG will be composited on green (#00ff00) by default if it has an alpha
+ * channel), and apply the intermediate image generated above to specified
+ * locations in the image.
+ *
+ * The command line has the general format:
+ *
+ * simpleover <background.png> [output.png]
+ * {--sprite=width,height,name {[--at=x,y] {sprite.png}}}
+ * {--add=name {x,y}}
+ *
+ * The --sprite and --add options may occur multiple times. They are executed
+ * in order. --add may refer to any sprite already read.
+ *
+ * This code is intended to show how to composite multiple images together
+ * correctly. Apart from the libpng Simplified API the only work done in here
+ * is to combine multiple input PNG images into a single sprite; this involves
+ * a Porter-Duff 'over' operation and the input PNG images may, as a result,
+ * be regarded as being layered one on top of the other with the first (leftmost
+ * on the command line) being at the bottom and the last on the top.
+ */
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <errno.h>
+
+/* Normally use <png.h> here to get the installed libpng, but this is done to
+ * ensure the code picks up the local libpng implementation, so long as this
+ * file is linked against a sufficiently recent libpng (1.6+) it is ok to
+ * change this to <png.h>:
+ */
+#include "../../png.h"
+
+#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
+
+#define sprite_name_chars 15
+struct sprite {
+ FILE *file;
+ png_uint_16p buffer;
+ unsigned int width;
+ unsigned int height;
+ char name[sprite_name_chars+1];
+};
+
+#if 0 /* div by 65535 test program */
+#include <math.h>
+#include <stdio.h>
+
+int main(void) {
+ double err = 0;
+ unsigned int xerr = 0;
+ unsigned int r = 32769;
+ {
+ unsigned int x = 0;
+
+ do {
+ unsigned int t = x + (x >> 16) /*+ (x >> 31)*/ + r;
+ double v = x, errtest;
+
+ if (t < x) {
+ fprintf(stderr, "overflow: %u+%u -> %u\n", x, r, t);
+ return 1;
+ }
+
+ v /= 65535;
+ errtest = v;
+ t >>= 16;
+ errtest -= t;
+
+ if (errtest > err) {
+ err = errtest;
+ xerr = x;
+
+ if (errtest >= .5) {
+ fprintf(stderr, "error: %u/65535 = %f, not %u, error %f\n",
+ x, v, t, errtest);
+ return 0;
+ }
+ }
+ } while (++x <= 65535U*65535U);
+ }
+
+ printf("error %f @ %u\n", err, xerr);
+
+ return 0;
+}
+#endif /* div by 65535 test program */
+
+static void
+sprite_op(const struct sprite *sprite, int x_offset, int y_offset,
+ png_imagep image, const png_uint_16 *buffer)
+{
+ /* This is where the Porter-Duff 'Over' operator is evaluated; change this
+ * code to change the operator (this could be parameterized). Any other
+ * image processing operation could be used here.
+ */
+
+
+ /* Check for an x or y offset that pushes any part of the image beyond the
+ * right or bottom of the sprite:
+ */
+ if ((y_offset < 0 || (unsigned)/*SAFE*/y_offset < sprite->height) &&
+ (x_offset < 0 || (unsigned)/*SAFE*/x_offset < sprite->width))
+ {
+ unsigned int y = 0;
+
+ if (y_offset < 0)
+ y = -y_offset; /* Skip to first visible row */
+
+ do
+ {
+ unsigned int x = 0;
+
+ if (x_offset < 0)
+ x = -x_offset;
+
+ do
+ {
+ /* In and out are RGBA values, so: */
+ const png_uint_16 *in_pixel = buffer + (y * image->width + x)*4;
+ png_uint_32 in_alpha = in_pixel[3];
+
+ /* This is the optimized Porter-Duff 'Over' operation, when the
+ * input alpha is 0 the output is not changed.
+ */
+ if (in_alpha > 0)
+ {
+ png_uint_16 *out_pixel = sprite->buffer +
+ ((y+y_offset) * sprite->width + (x+x_offset))*4;
+
+ /* This is the weight to apply to the output: */
+ in_alpha = 65535-in_alpha;
+
+ if (in_alpha > 0)
+ {
+ /* The input must be composed onto the output. This means
+ * multiplying the current output pixel value by the inverse
+ * of the input alpha (1-alpha). A division is required but
+ * it is by the constant 65535. Approximate this as:
+ *
+ * (x + (x >> 16) + 32769) >> 16;
+ *
+ * This is exact (and does not overflow) for all values of
+ * x in the range 0..65535*65535. (Note that the calculation
+ * produces the closest integer; the maximum error is <0.5).
+ */
+ png_uint_32 tmp;
+
+# define compose(c)\
+ tmp = out_pixel[c] * in_alpha;\
+ tmp = (tmp + (tmp >> 16) + 32769) >> 16;\
+ out_pixel[c] = tmp + in_pixel[c]
+
+ /* The following is very vectorizable... */
+ compose(0);
+ compose(1);
+ compose(2);
+ compose(3);
+ }
+
+ else
+ out_pixel[0] = in_pixel[0],
+ out_pixel[1] = in_pixel[1],
+ out_pixel[2] = in_pixel[2],
+ out_pixel[3] = in_pixel[3];
+ }
+ }
+ while (++x < image->width);
+ }
+ while (++y < image->height);
+ }
+}
+
+static int
+create_sprite(struct sprite *sprite, int *argc, const char ***argv)
+{
+ /* Read the arguments and create this sprite. The sprite buffer has already
+ * been allocated. This reads the input PNGs one by one in linear format,
+ * composes them onto the sprite buffer (the code in the function above)
+ * then saves the result, converting it on the fly to PNG RGBA 8-bit format.
+ */
+ while (*argc > 0)
+ {
+ char tombstone;
+ int x = 0, y = 0;
+
+ if ((*argv)[0][0] == '-' && (*argv)[0][1] == '-')
+ {
+ /* The only supported option is --at. */
+ if (sscanf((*argv)[0], "--at=%d,%d%c", &x, &y, &tombstone) != 2)
+ break; /* success; caller will parse this option */
+
+ ++*argv, --*argc;
+ }
+
+ else
+ {
+ /* The argument has to be a file name */
+ png_image image;
+
+ image.version = PNG_IMAGE_VERSION;
+ image.opaque = NULL;
+
+ if (png_image_begin_read_from_file(&image, (*argv)[0]))
+ {
+ png_uint_16p buffer;
+
+ image.format = PNG_FORMAT_LINEAR_RGB_ALPHA;
+
+ buffer = malloc(PNG_IMAGE_SIZE(image));
+
+ if (buffer != NULL)
+ {
+ if (png_image_finish_read(&image, NULL/*background*/, buffer,
+ 0/*row_stride*/,
+ NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP*/))
+ {
+ /* This is the place where the Porter-Duff 'Over' operator
+ * needs to be done by this code. In fact, any image
+ * processing required can be done here; the data is in
+ * the correct format (linear, 16-bit) and source and
+ * destination are in memory.
+ */
+ sprite_op(sprite, x, y, &image, buffer);
+ free(buffer);
+ ++*argv, --*argc;
+ /* And continue to the next argument */
+ continue;
+ }
+
+ else
+ {
+ free(buffer);
+ fprintf(stderr, "simpleover: read %s: %s\n", (*argv)[0],
+ image.message);
+ }
+ }
+
+ else
+ {
+ fprintf(stderr, "simpleover: out of memory: %lu bytes\n",
+ (unsigned long)PNG_IMAGE_SIZE(image));
+
+ /* png_image_free must be called if we abort the Simplified API
+ * read because of a problem detected in this code. If problems
+ * are detected in the Simplified API it cleans up itself.
+ */
+ png_image_free(&image);
+ }
+ }
+
+ else
+ {
+ /* Failed to read the first argument: */
+ fprintf(stderr, "simpleover: %s: %s\n", (*argv)[0], image.message);
+ }
+
+ return 0; /* failure */
+ }
+ }
+
+ /* All the sprite operations have completed successfully. Save the RGBA
+ * buffer as a PNG using the simplified write API.
+ */
+ sprite->file = tmpfile();
+
+ if (sprite->file != NULL)
+ {
+ png_image save;
+
+ memset(&save, 0, sizeof save);
+ save.version = PNG_IMAGE_VERSION;
+ save.opaque = NULL;
+ save.width = sprite->width;
+ save.height = sprite->height;
+ save.format = PNG_FORMAT_LINEAR_RGB_ALPHA;
+ save.flags = PNG_IMAGE_FLAG_FAST;
+ save.colormap_entries = 0;
+
+ if (png_image_write_to_stdio(&save, sprite->file, 1/*convert_to_8_bit*/,
+ sprite->buffer, 0/*row_stride*/, NULL/*colormap*/))
+ {
+ /* Success; the buffer is no longer needed: */
+ free(sprite->buffer);
+ sprite->buffer = NULL;
+ return 1; /* ok */
+ }
+
+ else
+ fprintf(stderr, "simpleover: write sprite %s: %s\n", sprite->name,
+ save.message);
+ }
+
+ else
+ fprintf(stderr, "simpleover: sprite %s: could not allocate tmpfile: %s\n",
+ sprite->name, strerror(errno));
+
+ return 0; /* fail */
+}
+
+static int
+add_sprite(png_imagep output, png_bytep out_buf, struct sprite *sprite,
+ int *argc, const char ***argv)
+{
+ /* Given a --add argument naming this sprite, perform the operations listed
+ * in the following arguments. The arguments are expected to have the form
+ * (x,y), which is just an offset at which to add the sprite to the
+ * output.
+ */
+ while (*argc > 0)
+ {
+ char tombstone;
+ int x, y;
+
+ if ((*argv)[0][0] == '-' && (*argv)[0][1] == '-')
+ return 1; /* success */
+
+ if (sscanf((*argv)[0], "%d,%d%c", &x, &y, &tombstone) == 2)
+ {
+ /* Now add the new image into the sprite data, but only if it
+ * will fit.
+ */
+ if (x < 0 || y < 0 ||
+ (unsigned)/*SAFE*/x >= output->width ||
+ (unsigned)/*SAFE*/y >= output->height ||
+ sprite->width > output->width-x ||
+ sprite->height > output->height-y)
+ {
+ fprintf(stderr, "simpleover: sprite %s @ (%d,%d) outside image\n",
+ sprite->name, x, y);
+ /* Could just skip this, but for the moment it is an error */
+ return 0; /* error */
+ }
+
+ else
+ {
+ /* Since we know the sprite fits we can just read it into the
+ * output using the simplified API.
+ */
+ png_image in;
+
+ in.version = PNG_IMAGE_VERSION;
+ rewind(sprite->file);
+
+ if (png_image_begin_read_from_stdio(&in, sprite->file))
+ {
+ in.format = PNG_FORMAT_RGB; /* force compose */
+
+ if (png_image_finish_read(&in, NULL/*background*/,
+ out_buf + (y*output->width + x)*3/*RGB*/,
+ output->width*3/*row_stride*/,
+ NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP*/))
+ {
+ ++*argv, --*argc;
+ continue;
+ }
+ }
+
+ /* The read failed: */
+ fprintf(stderr, "simpleover: add sprite %s: %s\n", sprite->name,
+ in.message);
+ return 0; /* error */
+ }
+ }
+
+ else
+ {
+ fprintf(stderr, "simpleover: --add='%s': invalid position %s\n",
+ sprite->name, (*argv)[0]);
+ return 0; /* error */
+ }
+ }
+
+ return 1; /* ok */
+}
+
+static int
+simpleover_process(png_imagep output, png_bytep out_buf, int argc,
+ const char **argv)
+{
+ int result = 1; /* success */
+# define csprites 10/*limit*/
+# define str(a) #a
+ int nsprites = 0;
+ struct sprite sprites[csprites];
+
+ while (argc > 0)
+ {
+ result = 0; /* fail */
+
+ if (strncmp(argv[0], "--sprite=", 9) == 0)
+ {
+ char tombstone;
+
+ if (nsprites < csprites)
+ {
+ int n;
+
+ sprites[nsprites].width = sprites[nsprites].height = 0;
+ sprites[nsprites].name[0] = 0;
+
+ n = sscanf(argv[0], "--sprite=%u,%u,%" str(sprite_name_chars) "s%c",
+ &sprites[nsprites].width, &sprites[nsprites].height,
+ sprites[nsprites].name, &tombstone);
+
+ if ((n == 2 || n == 3) &&
+ sprites[nsprites].width > 0 && sprites[nsprites].height > 0)
+ {
+ size_t buf_size, tmp;
+
+ /* Default a name if not given. */
+ if (sprites[nsprites].name[0] == 0)
+ sprintf(sprites[nsprites].name, "sprite-%d", nsprites+1);
+
+ /* Allocate a buffer for the sprite and calculate the buffer
+ * size:
+ */
+ buf_size = sizeof (png_uint_16 [4]);
+ buf_size *= sprites[nsprites].width;
+ buf_size *= sprites[nsprites].height;
+
+ /* This can overflow a (size_t); check for this: */
+ tmp = buf_size;
+ tmp /= sprites[nsprites].width;
+ tmp /= sprites[nsprites].height;
+
+ if (tmp == sizeof (png_uint_16 [4]))
+ {
+ sprites[nsprites].buffer = malloc(buf_size);
+ /* This buffer must be initialized to transparent: */
+ memset(sprites[nsprites].buffer, 0, buf_size);
+
+ if (sprites[nsprites].buffer != NULL)
+ {
+ sprites[nsprites].file = NULL;
+ ++argv, --argc;
+
+ if (create_sprite(sprites+nsprites++, &argc, &argv))
+ {
+ result = 1; /* still ok */
+ continue;
+ }
+
+ break; /* error */
+ }
+ }
+
+ /* Overflow, or OOM */
+ fprintf(stderr, "simpleover: %s: sprite too large\n", argv[0]);
+ break;
+ }
+
+ else
+ {
+ fprintf(stderr, "simpleover: %s: invalid sprite (%u,%u)\n",
+ argv[0], sprites[nsprites].width, sprites[nsprites].height);
+ break;
+ }
+ }
+
+ else
+ {
+ fprintf(stderr, "simpleover: %s: too many sprites\n", argv[0]);
+ break;
+ }
+ }
+
+ else if (strncmp(argv[0], "--add=", 6) == 0)
+ {
+ const char *name = argv[0]+6;
+ int isprite = nsprites;
+
+ ++argv, --argc;
+
+ while (--isprite >= 0)
+ {
+ if (strcmp(sprites[isprite].name, name) == 0)
+ {
+ if (!add_sprite(output, out_buf, sprites+isprite, &argc, &argv))
+ goto out; /* error in add_sprite */
+
+ break;
+ }
+ }
+
+ if (isprite < 0) /* sprite not found */
+ {
+ fprintf(stderr, "simpleover: --add='%s': sprite not found\n", name);
+ break;
+ }
+ }
+
+ else
+ {
+ fprintf(stderr, "simpleover: %s: unrecognized operation\n", argv[0]);
+ break;
+ }
+
+ result = 1; /* ok */
+ }
+
+ /* Clean up the cache of sprites: */
+out:
+ while (--nsprites >= 0)
+ {
+ if (sprites[nsprites].buffer != NULL)
+ free(sprites[nsprites].buffer);
+
+ if (sprites[nsprites].file != NULL)
+ (void)fclose(sprites[nsprites].file);
+ }
+
+ return result;
+}
+
+int main(int argc, const char **argv)
+{
+ int result = 1; /* default to fail */
+
+ if (argc >= 2)
+ {
+ int argi = 2;
+ const char *output = NULL;
+ png_image image;
+
+ if (argc > 2 && argv[2][0] != '-'/*an operation*/)
+ {
+ output = argv[2];
+ argi = 3;
+ }
+
+ image.version = PNG_IMAGE_VERSION;
+ image.opaque = NULL;
+
+ if (png_image_begin_read_from_file(&image, argv[1]))
+ {
+ png_bytep buffer;
+
+ image.format = PNG_FORMAT_RGB; /* 24-bit RGB */
+
+ buffer = malloc(PNG_IMAGE_SIZE(image));
+
+ if (buffer != NULL)
+ {
+ png_color background = {0, 0xff, 0}; /* fully saturated green */
+
+ if (png_image_finish_read(&image, &background, buffer,
+ 0/*row_stride*/, NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP */))
+ {
+ /* At this point png_image_finish_read has cleaned up the
+ * allocated data in png_image, and only the buffer needs to be
+ * freed.
+ *
+ * Perform the remaining operations:
+ */
+ if (simpleover_process(&image, buffer, argc-argi, argv+argi))
+ {
+ /* Write the output: */
+ if ((output != NULL &&
+ png_image_write_to_file(&image, output,
+ 0/*convert_to_8bit*/, buffer, 0/*row_stride*/,
+ NULL/*colormap*/)) ||
+ (output == NULL &&
+ png_image_write_to_stdio(&image, stdout,
+ 0/*convert_to_8bit*/, buffer, 0/*row_stride*/,
+ NULL/*colormap*/)))
+ result = 0;
+
+ else
+ fprintf(stderr, "simpleover: write %s: %s\n",
+ output == NULL ? "stdout" : output, image.message);
+ }
+
+ /* else simpleover_process writes an error message */
+ }
+
+ else
+ fprintf(stderr, "simpleover: read %s: %s\n", argv[1],
+ image.message);
+
+ free(buffer);
+ }
+
+ else
+ {
+ fprintf(stderr, "simpleover: out of memory: %lu bytes\n",
+ (unsigned long)PNG_IMAGE_SIZE(image));
+
+ /* This is the only place where a 'free' is required; libpng does
+ * the cleanup on error and success, but in this case we couldn't
+ * complete the read because of running out of memory.
+ */
+ png_image_free(&image);
+ }
+ }
+
+ else
+ {
+ /* Failed to read the first argument: */
+ fprintf(stderr, "simpleover: %s: %s\n", argv[1], image.message);
+ }
+ }
+
+ else
+ {
+ /* Usage message */
+ fprintf(stderr,
+ "simpleover: usage: simpleover background.png [output.png]\n"
+ " Output 'background.png' as a 24-bit RGB PNG file in 'output.png'\n"
+ " or, if not given, stdout. 'background.png' will be composited\n"
+ " on fully saturated green.\n"
+ "\n"
+ " Optionally, before output, process additional PNG files:\n"
+ "\n"
+ " --sprite=width,height,name {[--at=x,y] {sprite.png}}\n"
+ " Produce a transparent sprite of size (width,height) and with\n"
+ " name 'name'.\n"
+ " For each sprite.png composite it using a Porter-Duff 'Over'\n"
+ " operation at offset (x,y) in the sprite (defaulting to (0,0)).\n"
+ " Input PNGs will be truncated to the area of the sprite.\n"
+ "\n"
+ " --add='name' {x,y}\n"
+ " Optionally, before output, composite a sprite, 'name', which\n"
+ " must have been previously produced using --sprite, at each\n"
+ " offset (x,y) in the output image. Each sprite must fit\n"
+ " completely within the output image.\n"
+ "\n"
+ " PNG files are processed in the order they occur on the command\n"
+ " line and thus the first PNG processed appears as the bottommost\n"
+ " in the output image.\n");
+ }
+
+ return result;
+}
+#endif /* SIMPLIFIED_READ */
diff --git a/libpng/contrib/gregbook/COPYING b/libpng/contrib/gregbook/COPYING
new file mode 100644
index 0000000..a3e9774
--- /dev/null
+++ b/libpng/contrib/gregbook/COPYING
@@ -0,0 +1,340 @@
+ GNU GENERAL PUBLIC LICENSE
+ Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+ 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
+ The licenses for most software are designed to take away your
+freedom to share and change it. By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users. This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it. (Some other Free Software Foundation software is covered by
+the GNU Library General Public License instead.) You can apply it to
+your programs, too.
+
+ When we speak of free software, we are referring to freedom, not
+price. Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+ To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+ For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have. You must make sure that they, too, receive or can get the
+source code. And you must show them these terms so they know their
+rights.
+
+ We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+ Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software. If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+ Finally, any free program is threatened constantly by software
+patents. We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary. To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+ The precise terms and conditions for copying, distribution and
+modification follow.
+
+ GNU GENERAL PUBLIC LICENSE
+ TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+ 0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License. The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language. (Hereinafter, translation is included without limitation in
+the term "modification".) Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope. The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+ 1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+ 2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+ a) You must cause the modified files to carry prominent notices
+ stating that you changed the files and the date of any change.
+
+ b) You must cause any work that you distribute or publish, that in
+ whole or in part contains or is derived from the Program or any
+ part thereof, to be licensed as a whole at no charge to all third
+ parties under the terms of this License.
+
+ c) If the modified program normally reads commands interactively
+ when run, you must cause it, when started running for such
+ interactive use in the most ordinary way, to print or display an
+ announcement including an appropriate copyright notice and a
+ notice that there is no warranty (or else, saying that you provide
+ a warranty) and that users may redistribute the program under
+ these conditions, and telling the user how to view a copy of this
+ License. (Exception: if the Program itself is interactive but
+ does not normally print such an announcement, your work based on
+ the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole. If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works. But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+ 3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+ a) Accompany it with the complete corresponding machine-readable
+ source code, which must be distributed under the terms of Sections
+ 1 and 2 above on a medium customarily used for software interchange; or,
+
+ b) Accompany it with a written offer, valid for at least three
+ years, to give any third party, for a charge no more than your
+ cost of physically performing source distribution, a complete
+ machine-readable copy of the corresponding source code, to be
+ distributed under the terms of Sections 1 and 2 above on a medium
+ customarily used for software interchange; or,
+
+ c) Accompany it with the information you received as to the offer
+ to distribute corresponding source code. (This alternative is
+ allowed only for noncommercial distribution and only if you
+ received the program in object code or executable form with such
+ an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it. For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable. However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+ 4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License. Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+ 5. You are not required to accept this License, since you have not
+signed it. However, nothing else grants you permission to modify or
+distribute the Program or its derivative works. These actions are
+prohibited by law if you do not accept this License. Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+ 6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions. You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+ 7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License. If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all. For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices. Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+ 8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded. In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+ 9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time. Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number. If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation. If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+ 10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission. For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this. Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+ NO WARRANTY
+
+ 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+ 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+ <one line to give the program's name and a brief idea of what it does.>
+ Copyright (C) <year> <name of author>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+ Gnomovision version 69, Copyright (C) year name of author
+ Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary. Here is a sample; alter the names:
+
+ Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+ `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+ <signature of Ty Coon>, 1 April 1989
+ Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs. If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library. If this is what you want to do, use the GNU Library General
+Public License instead of this License.
diff --git a/libpng/contrib/gregbook/LICENSE b/libpng/contrib/gregbook/LICENSE
new file mode 100644
index 0000000..d956717
--- /dev/null
+++ b/libpng/contrib/gregbook/LICENSE
@@ -0,0 +1,50 @@
+ ---------------------------------------------------------------------------
+
+ Copyright (c) 1998-2008 Greg Roelofs. All rights reserved.
+
+ This software is provided "as is," without warranty of any kind,
+ express or implied. In no event shall the author or contributors
+ be held liable for any damages arising in any way from the use of
+ this software.
+
+ The contents of this file are DUAL-LICENSED. You may modify and/or
+ redistribute this software according to the terms of one of the
+ following two licenses (at your option):
+
+
+ LICENSE 1 ("BSD-like with advertising clause"):
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute
+ it freely, subject to the following restrictions:
+
+ 1. Redistributions of source code must retain the above copyright
+ notice, disclaimer, and this list of conditions.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, disclaimer, and this list of conditions in the documenta-
+ tion and/or other materials provided with the distribution.
+ 3. All advertising materials mentioning features or use of this
+ software must display the following acknowledgment:
+
+ This product includes software developed by Greg Roelofs
+ and contributors for the book, "PNG: The Definitive Guide,"
+ published by O'Reilly and Associates.
+
+
+ LICENSE 2 (GNU GPL v2 or later):
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ ---------------------------------------------------------------------------
diff --git a/libpng/contrib/gregbook/Makefile.mingw32 b/libpng/contrib/gregbook/Makefile.mingw32
new file mode 100644
index 0000000..3a3ff60
--- /dev/null
+++ b/libpng/contrib/gregbook/Makefile.mingw32
@@ -0,0 +1,131 @@
+# Sample makefile for rpng-win / rpng2-win / wpng using mingw32-gcc and make.
+# Greg Roelofs
+# Last modified: 2 June 2007
+#
+# The programs built by this makefile are described in the book,
+# "PNG: The Definitive Guide," by Greg Roelofs (O'Reilly and
+# Associates, 1999). Go buy a copy, eh? Well, OK, it's not
+# generally for sale anymore, but it's the thought that counts,
+# right? (Hint: http://www.libpng.org/pub/png/book/ )
+#
+# Invoke this makefile from a DOS-prompt window via:
+#
+# make -f Makefile.mingw32
+#
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are in subdirectories at the same level as the current subdirectory
+# (as indicated by the PNGDIR and ZDIR macros below). It makes no assumptions
+# at all about the mingw32 installation tree (W32DIR). Edit as appropriate.
+#
+# Note that the names of the dynamic and static libpng and zlib libraries
+# used below may change in later releases of the libraries. This makefile
+# builds both statically and dynamically linked executables by default.
+# (You need only one set, but for testing it can be handy to have both.)
+
+
+# macros --------------------------------------------------------------------
+
+#PNGDIR = ../..# for libpng-x.y.z/contrib/gregbook builds
+PNGDIR = ../libpng-win32
+PNGINC = -I$(PNGDIR)
+PNGLIBd = $(PNGDIR)/libpng.dll.a # dynamically linked
+PNGLIBs = $(PNGDIR)/libpng.a # statically linked, local libpng
+
+#ZDIR = ../../../zlib-win32# for libpng-x.y.z/contrib/gregbook builds
+ZDIR = ../zlib-win32
+ZINC = -I$(ZDIR)
+ZLIBd = $(ZDIR)/libzdll.a
+ZLIBs = $(ZDIR)/libz.a
+
+# change this to be the path where mingw32 installs its stuff:
+W32DIR =
+#W32DIR = /usr/local/cross-tools/i386-mingw32msvc
+W32INC = -I$(W32DIR)/include
+W32LIB = $(W32DIR)/lib/libuser32.a $(W32DIR)/lib/libgdi32.a
+
+CC = gcc
+#CC = i386-mingw32msvc-gcc # e.g., Linux -> Win32 cross-compilation
+LD = $(CC)
+RM = rm -f
+CPPFLAGS = $(INCS)
+CFLAGS = -O -Wall $(MINGW_CCFLAGS)
+# [note that -Wall is a gcc-specific compilation flag ("most warnings on")]
+# [-ansi, -pedantic and -W can also be used]
+LDFLAGS = $(MINGW_LDFLAGS)
+O = .o
+E = .exe
+
+INCS = $(PNGINC) $(ZINC) $(W32INC)
+RLIBSd = $(PNGLIBd) $(ZLIBd) $(W32LIB) -lm
+RLIBSs = $(PNGLIBs) $(ZLIBs) $(W32LIB) -lm
+WLIBSd = $(PNGLIBd) $(ZLIBd)
+WLIBSs = $(PNGLIBs) $(ZLIBs)
+
+RPNG = rpng-win
+RPNG2 = rpng2-win
+WPNG = wpng
+
+ROBJSd = $(RPNG)$(O) readpng.pic$(O)
+ROBJS2d = $(RPNG2)$(O) readpng2.pic$(O)
+WOBJSd = $(WPNG)$(O) writepng.pic$(O)
+
+RPNGs = $(RPNG)-static
+RPNG2s = $(RPNG2)-static
+WPNGs = $(WPNG)-static
+
+ROBJSs = $(RPNG)$(O) readpng$(O)
+ROBJS2s = $(RPNG2)$(O) readpng2$(O)
+WOBJSs = $(WPNG)$(O) writepng$(O)
+
+STATIC_EXES = $(RPNGs)$(E) $(RPNG2s)$(E) $(WPNGs)$(E)
+DYNAMIC_EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+EXES = $(STATIC_EXES) $(DYNAMIC_EXES)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+ $(CC) -c $(CPPFLAGS) $(CFLAGS) $<
+
+%.pic$(O): %.c
+ $(CC) -c $(CPPFLAGS) $(CFLAGS) -DPNG_BUILD_DLL -o $@ $<
+
+
+# dependencies --------------------------------------------------------------
+
+all: $(EXES)
+
+$(RPNGs)$(E): $(ROBJSs)
+ $(LD) $(LDFLAGS) -o $@ $(ROBJSs) $(RLIBSs)
+
+$(RPNG)$(E): $(ROBJSd)
+ $(LD) $(LDFLAGS) -o $@ $(ROBJSd) $(RLIBSd)
+
+$(RPNG2s)$(E): $(ROBJS2s)
+ $(LD) $(LDFLAGS) -o $@ $(ROBJS2s) $(RLIBSs)
+
+$(RPNG2)$(E): $(ROBJS2d)
+ $(LD) $(LDFLAGS) -o $@ $(ROBJS2d) $(RLIBSd)
+
+$(WPNGs)$(E): $(WOBJSs)
+ $(LD) $(LDFLAGS) -o $@ $(WOBJSs) $(WLIBSs)
+
+$(WPNG)$(E): $(WOBJSd)
+ $(LD) $(LDFLAGS) -o $@ $(WOBJSd) $(WLIBSd)
+
+$(RPNG)$(O): $(RPNG).c readpng.h
+$(RPNG2)$(O): $(RPNG2).c readpng2.h
+$(WPNG)$(O): $(WPNG).c writepng.h
+
+readpng$(O) readpng.pic$(O): readpng.c readpng.h
+readpng2$(O) readpng2.pic$(O): readpng2.c readpng2.h
+writepng$(O) writepng.pic$(O): writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+ $(RM) $(EXES)
+ $(RM) $(ROBJSs) $(ROBJS2s) $(WOBJSs)
+ $(RM) $(ROBJSd) $(ROBJS2d) $(WOBJSd)
diff --git a/libpng/contrib/gregbook/Makefile.sgi b/libpng/contrib/gregbook/Makefile.sgi
new file mode 100644
index 0000000..94d61b4
--- /dev/null
+++ b/libpng/contrib/gregbook/Makefile.sgi
@@ -0,0 +1,105 @@
+# Sample makefile for rpng-x / rpng2-x / wpng for SGI using cc and make.
+# Greg Roelofs
+# Last modified: 7 March 2002
+#
+# The programs built by this makefile are described in the book,
+# "PNG: The Definitive Guide," by Greg Roelofs (O'Reilly and
+# Associates, 1999). Go buy a copy, eh? Buy some for friends
+# and family, too. (Not that this is a blatant plug or anything.)
+#
+# Invoke this makefile from a shell prompt in the usual way; for example:
+#
+# make -f Makefile.sgi
+#
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are both installed in /usr/local/{include,lib} (as indicated by the
+# PNG* and Z* macros below). Edit as appropriate--choose only ONE each of
+# the PNGINC, PNGLIB, ZINC and ZLIB lines.
+#
+# This makefile builds dynamically linked executables (against libpng and zlib,
+# that is), but that can be changed by uncommenting the appropriate PNGLIB and
+# ZLIB lines.
+
+
+# macros --------------------------------------------------------------------
+
+PNGINC = -I/usr/local/include/libpng16
+PNGLIB = -L/usr/local/lib -lpng16 # dynamically linked against libpng
+#PNGLIB = /usr/local/lib/libpng16.a # statically linked against libpng
+# or:
+#PNGINC = -I../..
+#PNGLIB = -L../.. -lpng
+#PNGLIB = ../../libpng.a
+
+ZINC = -I/usr/local/include
+ZLIB = -L/usr/local/lib -lz # dynamically linked against zlib
+#ZLIB = /usr/local/lib/libz.a # statically linked against zlib
+#ZINC = -I../zlib
+#ZLIB = -L../zlib -lz
+#ZLIB = ../../../zlib/libz.a
+
+XINC = -I/usr/include/X11 # old-style, stock X distributions
+XLIB = -L/usr/lib/X11 -lX11
+#XINC = -I/usr/openwin/include # Sun workstations (OpenWindows)
+#XLIB = -L/usr/openwin/lib -lX11
+#XINC = -I/usr/X11R6/include # new X distributions (XFree86, etc.)
+#XLIB = -L/usr/X11R6/lib -lX11
+
+INCS = $(PNGINC) $(ZINC) $(XINC)
+RLIBS = $(PNGLIB) $(ZLIB) $(XLIB) -lm
+WLIBS = $(PNGLIB) $(ZLIB)
+
+CC = cc
+LD = cc
+RM = rm -f
+# ABI must be the same as that used to build libpng.
+ABI =
+CPPFLAGS =
+CFLAGS = $(ABI) -O -fullwarn $(INCS)
+LDFLAGS = $(ABI)
+O = .o
+E =
+
+RPNG = rpng-x
+RPNG2 = rpng2-x
+WPNG = wpng
+
+ROBJS = $(RPNG)$(O) readpng$(O)
+ROBJS2 = $(RPNG2)$(O) readpng2$(O)
+WOBJS = $(WPNG)$(O) writepng$(O)
+
+EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+ $(CC) -c $(CPPFLAGS) $(CFLAGS) $<
+
+
+# dependencies --------------------------------------------------------------
+
+all: $(EXES)
+
+$(RPNG)$(E): $(ROBJS)
+ $(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBS)
+
+$(RPNG2)$(E): $(ROBJS2)
+ $(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBS)
+
+$(WPNG)$(E): $(WOBJS)
+ $(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBS)
+
+$(RPNG)$(O): $(RPNG).c readpng.h
+$(RPNG2)$(O): $(RPNG2).c readpng2.h
+$(WPNG)$(O): $(WPNG).c writepng.h
+
+readpng$(O): readpng.c readpng.h
+readpng2$(O): readpng2.c readpng2.h
+writepng$(O): writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+ $(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)
diff --git a/libpng/contrib/gregbook/Makefile.unx b/libpng/contrib/gregbook/Makefile.unx
new file mode 100644
index 0000000..1a73e03
--- /dev/null
+++ b/libpng/contrib/gregbook/Makefile.unx
@@ -0,0 +1,134 @@
+# Sample makefile for rpng-x / rpng2-x / wpng using gcc and make.
+# Greg Roelofs
+# Last modified: 2 June 2007
+#
+# The programs built by this makefile are described in the book,
+# "PNG: The Definitive Guide," by Greg Roelofs (O'Reilly and
+# Associates, 1999). Go buy a copy, eh? Well, OK, it's not
+# generally for sale anymore, but it's the thought that counts,
+# right? (Hint: http://www.libpng.org/pub/png/book/ )
+#
+# Invoke this makefile from a shell prompt in the usual way; for example:
+#
+# make -f Makefile.unx
+#
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are installed in /usr/local/{include,lib} or as otherwise indicated by
+# the PNG* and Z* macros below. Edit as appropriate--choose only ONE each of
+# the PNGINC, PNGLIBd, PNGLIBs, ZINC, ZLIBd and ZLIBs lines.
+#
+# This makefile builds both dynamically and statically linked executables
+# (against libpng and zlib, that is), but that can be changed by modifying
+# the "EXES =" line. (You need only one set, but for testing it can be handy
+# to have both.)
+
+
+# macros --------------------------------------------------------------------
+
+#PNGDIR = /usr/local/lib
+#PNGINC = -I/usr/local/include/libpng16
+#PNGLIBd = -L$(PNGDIR) -lpng16 # dynamically linked, installed libpng
+#PNGLIBs = $(PNGDIR)/libpng16.a # statically linked, installed libpng
+# or:
+PNGDIR = ../..# this one is for libpng-x.y.z/contrib/gregbook builds
+#PNGDIR = ../libpng
+PNGINC = -I$(PNGDIR)
+PNGLIBd = -Wl,-rpath,$(PNGDIR) -L$(PNGDIR) -lpng16 # dynamically linked
+PNGLIBs = $(PNGDIR)/libpng.a # statically linked, local libpng
+
+ZDIR = /usr/local/lib
+#ZDIR = /usr/lib64
+ZINC = -I/usr/local/include
+ZLIBd = -L$(ZDIR) -lz # dynamically linked against zlib
+ZLIBs = $(ZDIR)/libz.a # statically linked against zlib
+# or:
+#ZDIR = ../zlib
+#ZINC = -I$(ZDIR)
+#ZLIBd = -Wl,-rpath,$(ZDIR) -L$(ZDIR) -lz # -rpath allows in-place testing
+#ZLIBs = $(ZDIR)/libz.a
+
+#XINC = -I/usr/include # old-style, stock X distributions
+#XLIB = -L/usr/lib/X11 -lX11 # (including SGI IRIX)
+#XINC = -I/usr/openwin/include # Sun workstations (OpenWindows)
+#XLIB = -L/usr/openwin/lib -lX11
+XINC = -I/usr/X11R6/include # new X distributions (X.org, etc.)
+XLIB = -L/usr/X11R6/lib -lX11
+#XLIB = -L/usr/X11R6/lib64 -lX11 # e.g., Red Hat on AMD64
+
+INCS = $(PNGINC) $(ZINC) $(XINC)
+RLIBSd = $(PNGLIBd) $(ZLIBd) $(XLIB) -lm
+RLIBSs = $(PNGLIBs) $(ZLIBs) $(XLIB) -lm
+WLIBSd = $(PNGLIBd) $(ZLIBd) -lm
+WLIBSs = $(PNGLIBs) $(ZLIBs) -lm
+
+CC = gcc
+LD = gcc
+RM = rm -f
+CPPFLAGS = $(INCS) -DFEATURE_LOOP
+CFLAGS = -O -Wall
+#CFLAGS = -O -W -Wall -Wextra -pedantic -ansi
+# [note that -Wall is a gcc-specific compilation flag ("most warnings on")]
+# [-ansi, -pedantic, -Wextra, and -W can also be used]
+LDFLAGS =
+O = .o
+E =
+
+RPNG = rpng-x
+RPNG2 = rpng2-x
+WPNG = wpng
+
+RPNGs = $(RPNG)-static
+RPNG2s = $(RPNG2)-static
+WPNGs = $(WPNG)-static
+
+ROBJS = $(RPNG)$(O) readpng$(O)
+ROBJS2 = $(RPNG2)$(O) readpng2$(O)
+WOBJS = $(WPNG)$(O) writepng$(O)
+
+STATIC_EXES = $(RPNGs)$(E) $(RPNG2s)$(E) $(WPNGs)$(E)
+DYNAMIC_EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+EXES = $(STATIC_EXES) $(DYNAMIC_EXES)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+ $(CC) -c $(CPPFLAGS) $(CFLAGS) $<
+
+
+# dependencies --------------------------------------------------------------
+
+all: $(EXES)
+
+$(RPNGs)$(E): $(ROBJS)
+ $(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBSs)
+
+$(RPNG)$(E): $(ROBJS)
+ $(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBSd)
+
+$(RPNG2s)$(E): $(ROBJS2)
+ $(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBSs)
+
+$(RPNG2)$(E): $(ROBJS2)
+ $(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBSd)
+
+$(WPNGs)$(E): $(WOBJS)
+ $(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBSs)
+
+$(WPNG)$(E): $(WOBJS)
+ $(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBSd)
+
+$(RPNG)$(O): $(RPNG).c readpng.h
+$(RPNG2)$(O): $(RPNG2).c readpng2.h
+$(WPNG)$(O): $(WPNG).c writepng.h
+
+readpng$(O): readpng.c readpng.h
+readpng2$(O): readpng2.c readpng2.h
+writepng$(O): writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+ $(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)
diff --git a/libpng/contrib/gregbook/Makefile.w32 b/libpng/contrib/gregbook/Makefile.w32
new file mode 100644
index 0000000..ab7dcf7
--- /dev/null
+++ b/libpng/contrib/gregbook/Makefile.w32
@@ -0,0 +1,114 @@
+# Sample makefile for rpng-win / rpng2-win / wpng using MSVC and NMAKE.
+# Greg Roelofs
+# Last modified: 2 June 2007
+#
+# The programs built by this makefile are described in the book,
+# "PNG: The Definitive Guide," by Greg Roelofs (O'Reilly and
+# Associates, 1999). Go buy a copy, eh? Well, OK, it's not
+# generally for sale anymore, but it's the thought that counts,
+# right? (Hint: http://www.libpng.org/pub/png/book/ )
+#
+# Invoke this makefile from a DOS prompt window via:
+#
+# %devstudio%\vc\bin\vcvars32.bat
+# nmake -nologo -f Makefile.w32
+#
+# where %devstudio% is the installation directory for MSVC / DevStudio. If
+# you get "environment out of space" errors, create a desktop shortcut with
+# "c:\windows\command.com /e:4096" as the program command line and set the
+# working directory to this directory. Then double-click to open the new
+# DOS-prompt window with a bigger environment and retry the commands above.
+#
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are in subdirectories at the same level as the current subdirectory
+# (as indicated by the PNGPATH and ZPATH macros below). Edit as appropriate.
+#
+# Note that the names of the dynamic and static libpng and zlib libraries
+# used below may change in later releases of the libraries. This makefile
+# builds statically linked executables, but that can be changed by uncom-
+# menting the appropriate PNGLIB and ZLIB lines.
+
+!include <ntwin32.mak>
+
+
+# macros --------------------------------------------------------------------
+
+PNGPATH = ../libpng
+PNGINC = -I$(PNGPATH)
+#PNGLIB = $(PNGPATH)/pngdll.lib
+PNGLIB = $(PNGPATH)/libpng.lib
+
+ZPATH = ../zlib
+ZINC = -I$(ZPATH)
+#ZLIB = $(ZPATH)/zlibdll.lib
+ZLIB = $(ZPATH)/zlibstat.lib
+
+WINLIBS = -defaultlib:user32.lib gdi32.lib
+# ["real" apps may also need comctl32.lib, comdlg32.lib, winmm.lib, etc.]
+
+INCS = $(PNGINC) $(ZINC)
+RLIBS = $(PNGLIB) $(ZLIB) $(WINLIBS)
+WLIBS = $(PNGLIB) $(ZLIB)
+
+CC = cl
+LD = link
+RM = del
+CPPFLAGS = $(INCS)
+CFLAGS = -nologo -O -W3 $(cvars)
+# [note that -W3 is an MSVC-specific compilation flag ("all warnings on")]
+# [see %devstudio%\vc\include\win32.mak for cvars macro definition]
+O = .obj
+E = .exe
+
+RLDFLAGS = -nologo -subsystem:windows
+WLDFLAGS = -nologo
+
+RPNG = rpng-win
+RPNG2 = rpng2-win
+WPNG = wpng
+
+ROBJS = $(RPNG)$(O) readpng$(O)
+ROBJS2 = $(RPNG2)$(O) readpng2$(O)
+WOBJS = $(WPNG)$(O) writepng$(O)
+
+EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+ $(CC) -c $(CPPFLAGS) $(CFLAGS) $<
+
+
+# dependencies --------------------------------------------------------------
+
+all: $(EXES)
+
+$(RPNG)$(E): $(ROBJS)
+ $(LD) $(RLDFLAGS) -out:$@ $(ROBJS) $(RLIBS)
+
+$(RPNG2)$(E): $(ROBJS2)
+ $(LD) $(RLDFLAGS) -out:$@ $(ROBJS2) $(RLIBS)
+
+$(WPNG)$(E): $(WOBJS)
+ $(LD) $(WLDFLAGS) -out:$@ $(WOBJS) $(WLIBS)
+
+$(RPNG)$(O): $(RPNG).c readpng.h
+$(RPNG2)$(O): $(RPNG2).c readpng2.h
+$(WPNG)$(O): $(WPNG).c writepng.h
+
+readpng$(O): readpng.c readpng.h
+readpng2$(O): readpng2.c readpng2.h
+writepng$(O): writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+# ideally we could just do this:
+# $(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)
+# ...but the Windows "DEL" command is none too bright, so:
+ $(RM) r*$(E)
+ $(RM) w*$(E)
+ $(RM) r*$(O)
+ $(RM) w*$(O)
diff --git a/libpng/contrib/gregbook/README b/libpng/contrib/gregbook/README
new file mode 100644
index 0000000..7b1f6a3
--- /dev/null
+++ b/libpng/contrib/gregbook/README
@@ -0,0 +1,186 @@
+ ===========================
+ PNG: The Definitive Guide
+ ===========================
+
+ Source Code
+
+Chapters 13, 14 and 15 of "PNG: The Definitive Guide" discuss three free,
+cross-platform demo programs that show how to use the libpng reference
+library: rpng, rpng2 and wpng. rpng and rpng2 are viewers; the first is
+a very simple example that that shows how a standard file-viewer might use
+libpng, while the second is designed to process streaming data and shows
+how a web browser might be written. wpng is a simple command-line program
+that reads binary PGM and PPM files (the ``raw'' grayscale and RGB subsets
+of PBMPLUS/NetPBM) and converts them to PNG.
+
+The source code for all three demo programs currently compiles under
+Unix, OpenVMS, and 32-bit Windows. (Special thanks to Martin Zinser,
+zinser@decus.de, for making the necessary changes for OpenVMS and for
+providing an appropriate build script.) Build instructions can be found
+below.
+
+Files:
+
+ README this file
+ LICENSE terms of distribution and reuse (BSD-like or GNU GPL)
+ COPYING GNU General Public License (GPL)
+
+ Makefile.unx Unix makefile
+ Makefile.w32 Windows (MSVC) makefile
+ makevms.com OpenVMS build script
+
+ rpng-win.c Windows front end for the basic viewer
+ rpng-x.c X Window System (Unix, OpenVMS) front end
+ readpng.c generic back end for the basic viewer
+ readpng.h header file for the basic viewer
+
+ rpng2-win.c Windows front end for the progressive viewer
+ rpng2-x.c X front end for the progressive viewer
+ readpng2.c generic back end for the progressive viewer
+ readpng2.h header file for the progressive viewer
+
+ wpng.c generic (text) front end for the converter
+ writepng.c generic back end for the converter
+ writepng.h header file for the converter
+
+ toucan.png transparent PNG for testing (by Stefan Schneider)
+
+Note that, although the programs are designed to be functional, their
+primary purpose is to illustrate how to use libpng to add PNG support to
+other programs. As such, their user interfaces are crude and definitely
+are not intended for everyday use.
+
+Please see http://www.libpng.org/pub/png/pngbook.html for further infor-
+mation and links to the latest version of the source code, and Chapters
+13-15 of the book for detailed discussion of the three programs.
+
+Greg Roelofs
+http://pobox.com/~newt/greg_contact.html
+16 March 2008
+
+
+BUILD INSTRUCTIONS
+
+ - Prerequisites (in order of compilation):
+
+ - zlib http://zlib.net/
+ - libpng http://www.libpng.org/pub/png/libpng.html
+ - pngbook http://www.libpng.org/pub/png/book/sources.html
+
+ The pngbook demo programs are explicitly designed to demonstrate proper
+ coding techniques for using the libpng reference library. As a result,
+ you need to download and build both zlib (on which libpng depends) and
+ libpng. A common build setup is to place the zlib, libpng and pngbook
+ subdirectory trees ("folders") in the same parent directory. Then the
+ libpng build can refer to files in ../zlib (or ..\zlib or [-.zlib]),
+ and similarly for the pngbook build.
+
+ Note that all three packages are designed to be built from a command
+ line by default; those who wish to use a graphical or other integrated
+ development environments are on their own.
+
+
+ - Unix:
+
+ Unpack the latest pngbook sources (which should correspond to this
+ README file) into a directory and change into that directory.
+
+ Copy Makefile.unx to Makefile and edit the PNG* and Z* variables
+ appropriately (possibly also the X* variables if necessary).
+
+ make
+
+ There is no "install" target, so copy the three executables somewhere
+ in your path or run them from the current directory. All three will
+ print a basic usage screen when run without any command-line arguments;
+ see the book for more details.
+
+
+ - Windows:
+
+ Unpack the latest pngbook sources (which should correspond to this
+ README file) into a folder, open a "DOS shell" or "command prompt"
+ or equivalent command-line window, and cd into the folder where you
+ unpacked the source code.
+
+ For MSVC, set up the necessary environment variables by invoking
+
+ %devstudio%\vc\bin\vcvars32.bat
+
+ where where %devstudio% is the installation directory for MSVC /
+ DevStudio. If you get "environment out of space" errors under 95/98,
+ create a desktop shortcut with "c:\windows\command.com /e:4096" as
+ the program command line and set the working directory to the pngbook
+ directory. Then double-click to open the new DOS-prompt window with
+ a bigger environment and retry the commands above.
+
+ Copy Makefile.w32 to Makefile and edit the PNGPATH and ZPATH variables
+ appropriately (possibly also the "INC" and "LIB" variables if needed).
+ Note that the names of the dynamic and static libpng and zlib libraries
+ used in the makefile may change in later releases of the libraries.
+ Also note that, as of libpng version 1.0.5, MSVC DLL builds do not work.
+ This makefile therefore builds statically linked executables, but if
+ the DLL problems ever get fixed, uncommenting the appropriate PNGLIB
+ and ZLIB lines will build dynamically linked executables instead.
+
+ Do the build by typing
+
+ nmake
+
+ The result should be three executables: rpng-win.exe, rpng2-win.exe,
+ and wpng.exe. Copy them somewhere in your PATH or run them from the
+ current folder. Like the Unix versions, the two windowed programs
+ (rpng and rpng2) now display a usage screen in a console window when
+ invoked without command-line arguments; this is new behavior as of
+ the June 2001 release. Note that the programs use the Unix-style "-"
+ character to specify options, instead of the more common DOS/Windows
+ "/" character. (For example: "rpng2-win -bgpat 4 foo.png", not
+ "rpng2-win /bgpat 4 foo.png")
+
+
+ - OpenVMS:
+
+ Unpack the pngbook sources into a subdirectory and change into that
+ subdirectory.
+
+ Edit makevms.com appropriately, specifically the zpath and pngpath
+ variables.
+
+ @makevms
+
+ To run the programs, they probably first need to be set up as "foreign
+ symbols," with "disk" and "dir" set appropriately:
+
+ $ rpng == "$disk:[dir]rpng-x.exe"
+ $ rpng2 == "$disk:[dir]rpng2-x.exe"
+ $ wpng == "$disk:[dir]wpng.exe"
+
+ All three will print a basic usage screen when run without any command-
+ line arguments; see the book for more details. Note that the options
+ style is Unix-like, i.e., preceded by "-" rather than "/".
+
+
+RUNNING THE PROGRAMS: (VERY) BRIEF INTRO
+
+ rpng is a simple PNG viewer that can display transparent PNGs with a
+ specified background color; for example,
+
+ rpng -bgcolor \#ff0000 toucan.png
+
+ would display the image with a red background. rpng2 is a progressive
+ viewer that simulates a web browser in some respects; it can display
+ images against either a background color or a dynamically generated
+ background image. For example:
+
+ rpng2 -bgpat 16 toucan.png
+
+ wpng is a purely command-line image converter from binary PBMPLUS/NetPBM
+ format (.pgm or .ppm) to PNG; for example,
+
+ wpng -time < toucan-notrans.ppm > toucan-notrans.png
+
+ would convert the specified PPM file (using redirection) to PNG, auto-
+ matically setting the PNG modification-time chunk.
+
+ All options can be abbreviated to the shortest unique value; for example,
+ "-bgc" for -bgcolor (versus "-bgp" for -bgpat), or "-g" for -gamma.
diff --git a/libpng/contrib/gregbook/makevms.com b/libpng/contrib/gregbook/makevms.com
new file mode 100644
index 0000000..f32bcab
--- /dev/null
+++ b/libpng/contrib/gregbook/makevms.com
@@ -0,0 +1,132 @@
+$!------------------------------------------------------------------------------
+$! make "PNG: The Definitive Guide" demo programs (for X) under OpenVMS
+$!
+$! Script created by Martin Zinser for libpng; modified by Greg Roelofs
+$! for standalone pngbook source distribution.
+$!
+$!
+$! Set locations where zlib and libpng sources live.
+$!
+$ zpath = ""
+$ pngpath = ""
+$!
+$ if f$search("[---.zlib]zlib.h").nes."" then zpath = "[---.zlib]"
+$ if f$search("[--]png.h").nes."" then pngpath = "[--]"
+$!
+$ if f$search("[-.zlib]zlib.h").nes."" then zpath = "[-.zlib]"
+$ if f$search("[-.libpng]png.h").nes."" then pngpath = "[-.libpng]"
+$!
+$ if zpath .eqs. ""
+$ then
+$ write sys$output "zlib include not found. Exiting..."
+$ exit 2
+$ endif
+$!
+$ if pngpath .eqs. ""
+$ then
+$ write sys$output "libpng include not found. Exiting..."
+$ exit 2
+$ endif
+$!
+$! Look for the compiler used.
+$!
+$ ccopt="/include=(''zpath',''pngpath')"
+$ if f$getsyi("HW_MODEL").ge.1024
+$ then
+$ ccopt = "/prefix=all"+ccopt
+$ comp = "__decc__=1"
+$ if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$ else
+$ if f$search("SYS$SYSTEM:DECC$COMPILER.EXE").eqs.""
+$ then
+$ if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$ if f$search("SYS$SYSTEM:VAXC.EXE").eqs.""
+$ then
+$ comp = "__gcc__=1"
+$ CC :== GCC
+$ else
+$ comp = "__vaxc__=1"
+$ endif
+$ else
+$ if f$trnlnm("SYS").eqs."" then define sys decc$library_include:
+$ ccopt = "/decc/prefix=all"+ccopt
+$ comp = "__decc__=1"
+$ endif
+$ endif
+$ open/write lopt lib.opt
+$ write lopt "''pngpath'libpng.olb/lib"
+$ write lopt "''zpath'libz.olb/lib"
+$ close lopt
+$ open/write xopt x11.opt
+$ write xopt "sys$library:decw$xlibshr.exe/share"
+$ close xopt
+$!
+$! Build 'em.
+$!
+$ write sys$output "Compiling PNG book programs ..."
+$ CALL MAKE readpng.OBJ "cc ''CCOPT' readpng" -
+ readpng.c readpng.h
+$ CALL MAKE readpng2.OBJ "cc ''CCOPT' readpng2" -
+ readpng2.c readpng2.h
+$ CALL MAKE writepng.OBJ "cc ''CCOPT' writepng" -
+ writepng.c writepng.h
+$ write sys$output "Building rpng-x..."
+$ CALL MAKE rpng-x.OBJ "cc ''CCOPT' rpng-x" -
+ rpng-x.c readpng.h
+$ call make rpng-x.exe -
+ "LINK rpng-x,readpng,lib.opt/opt,x11.opt/opt" -
+ rpng-x.obj readpng.obj
+$ write sys$output "Building rpng2-x..."
+$ CALL MAKE rpng2-x.OBJ "cc ''CCOPT' rpng2-x" -
+ rpng2-x.c readpng2.h
+$ call make rpng2-x.exe -
+ "LINK rpng2-x,readpng2,lib.opt/opt,x11.opt/opt" -
+ rpng2-x.obj readpng2.obj
+$ write sys$output "Building wpng..."
+$ CALL MAKE wpng.OBJ "cc ''CCOPT' wpng" -
+ wpng.c writepng.h
+$ call make wpng.exe -
+ "LINK wpng,writepng,lib.opt/opt" -
+ wpng.obj writepng.obj
+$ exit
+$!
+$!
+$MAKE: SUBROUTINE !SUBROUTINE TO CHECK DEPENDENCIES
+$ V = 'F$Verify(0)
+$! P1 = What we are trying to make
+$! P2 = Command to make it
+$! P3 - P8 What it depends on
+$
+$ If F$Search(P1) .Eqs. "" Then Goto Makeit
+$ Time = F$CvTime(F$File(P1,"RDT"))
+$arg=3
+$Loop:
+$ Argument = P'arg
+$ If Argument .Eqs. "" Then Goto Exit
+$ El=0
+$Loop2:
+$ File = F$Element(El," ",Argument)
+$ If File .Eqs. " " Then Goto Endl
+$ AFile = ""
+$Loop3:
+$ OFile = AFile
+$ AFile = F$Search(File)
+$ If AFile .Eqs. "" .Or. AFile .Eqs. OFile Then Goto NextEl
+$ If F$CvTime(F$File(AFile,"RDT")) .Ges. Time Then Goto Makeit
+$ Goto Loop3
+$NextEL:
+$ El = El + 1
+$ Goto Loop2
+$EndL:
+$ arg=arg+1
+$ If arg .Le. 8 Then Goto Loop
+$ Goto Exit
+$
+$Makeit:
+$ VV=F$VERIFY(0)
+$ write sys$output P2
+$ 'P2
+$ VV='F$Verify(VV)
+$Exit:
+$ If V Then Set Verify
+$ENDSUBROUTINE
diff --git a/libpng/contrib/gregbook/readpng.c b/libpng/contrib/gregbook/readpng.c
new file mode 100644
index 0000000..9167403
--- /dev/null
+++ b/libpng/contrib/gregbook/readpng.c
@@ -0,0 +1,317 @@
+/*---------------------------------------------------------------------------
+
+ rpng - simple PNG display program readpng.c
+
+ ---------------------------------------------------------------------------
+
+ Copyright (c) 1998-2007 Greg Roelofs. All rights reserved.
+
+ This software is provided "as is," without warranty of any kind,
+ express or implied. In no event shall the author or contributors
+ be held liable for any damages arising in any way from the use of
+ this software.
+
+ The contents of this file are DUAL-LICENSED. You may modify and/or
+ redistribute this software according to the terms of one of the
+ following two licenses (at your option):
+
+
+ LICENSE 1 ("BSD-like with advertising clause"):
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute
+ it freely, subject to the following restrictions:
+
+ 1. Redistributions of source code must retain the above copyright
+ notice, disclaimer, and this list of conditions.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, disclaimer, and this list of conditions in the documenta-
+ tion and/or other materials provided with the distribution.
+ 3. All advertising materials mentioning features or use of this
+ software must display the following acknowledgment:
+
+ This product includes software developed by Greg Roelofs
+ and contributors for the book, "PNG: The Definitive Guide,"
+ published by O'Reilly and Associates.
+
+
+ LICENSE 2 (GNU GPL v2 or later):
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ ---------------------------------------------------------------------------*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <zlib.h>
+
+#include "png.h" /* libpng header */
+#include "readpng.h" /* typedefs, common macros, public prototypes */
+
+/* future versions of libpng will provide this macro: */
+#ifndef png_jmpbuf
+# define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
+#endif
+
+
+static png_structp png_ptr = NULL;
+static png_infop info_ptr = NULL;
+
+png_uint_32 width, height;
+int bit_depth, color_type;
+uch *image_data = NULL;
+
+
+void readpng_version_info(void)
+{
+ fprintf(stderr, " Compiled with libpng %s; using libpng %s.\n",
+ PNG_LIBPNG_VER_STRING, png_libpng_ver);
+ fprintf(stderr, " Compiled with zlib %s; using zlib %s.\n",
+ ZLIB_VERSION, zlib_version);
+}
+
+
+/* return value = 0 for success, 1 for bad sig, 2 for bad IHDR, 4 for no mem */
+
+int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight)
+{
+ uch sig[8];
+
+
+ /* first do a quick check that the file really is a PNG image; could
+ * have used slightly more general png_sig_cmp() function instead */
+
+ fread(sig, 1, 8, infile);
+ if (png_sig_cmp(sig, 0, 8))
+ return 1; /* bad signature */
+
+
+ /* could pass pointers to user-defined error handlers instead of NULLs: */
+
+ png_ptr = png_create_read_struct(png_get_libpng_ver(NULL), NULL, NULL,
+ NULL);
+ if (!png_ptr)
+ return 4; /* out of memory */
+
+ info_ptr = png_create_info_struct(png_ptr);
+ if (!info_ptr) {
+ png_destroy_read_struct(&png_ptr, NULL, NULL);
+ return 4; /* out of memory */
+ }
+
+
+ /* we could create a second info struct here (end_info), but it's only
+ * useful if we want to keep pre- and post-IDAT chunk info separated
+ * (mainly for PNG-aware image editors and converters) */
+
+
+ /* setjmp() must be called in every function that calls a PNG-reading
+ * libpng function */
+
+ if (setjmp(png_jmpbuf(png_ptr))) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ return 2;
+ }
+
+
+ png_init_io(png_ptr, infile);
+ png_set_sig_bytes(png_ptr, 8); /* we already read the 8 signature bytes */
+
+ png_read_info(png_ptr, info_ptr); /* read all PNG info up to image data */
+
+
+ /* alternatively, could make separate calls to png_get_image_width(),
+ * etc., but want bit_depth and color_type for later [don't care about
+ * compression_type and filter_type => NULLs] */
+
+ png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+ NULL, NULL, NULL);
+ *pWidth = width;
+ *pHeight = height;
+
+
+ /* OK, that's all we need for now; return happy */
+
+ return 0;
+}
+
+
+
+
+/* returns 0 if succeeds, 1 if fails due to no bKGD chunk, 2 if libpng error;
+ * scales values to 8-bit if necessary */
+
+int readpng_get_bgcolor(uch *red, uch *green, uch *blue)
+{
+ png_color_16p pBackground;
+
+
+ /* setjmp() must be called in every function that calls a PNG-reading
+ * libpng function */
+
+ if (setjmp(png_jmpbuf(png_ptr))) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ return 2;
+ }
+
+
+ if (!png_get_valid(png_ptr, info_ptr, PNG_INFO_bKGD))
+ return 1;
+
+ /* it is not obvious from the libpng documentation, but this function
+ * takes a pointer to a pointer, and it always returns valid red, green
+ * and blue values, regardless of color_type: */
+
+ png_get_bKGD(png_ptr, info_ptr, &pBackground);
+
+
+ /* however, it always returns the raw bKGD data, regardless of any
+ * bit-depth transformations, so check depth and adjust if necessary */
+
+ if (bit_depth == 16) {
+ *red = pBackground->red >> 8;
+ *green = pBackground->green >> 8;
+ *blue = pBackground->blue >> 8;
+ } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
+ if (bit_depth == 1)
+ *red = *green = *blue = pBackground->gray? 255 : 0;
+ else if (bit_depth == 2)
+ *red = *green = *blue = (255/3) * pBackground->gray;
+ else /* bit_depth == 4 */
+ *red = *green = *blue = (255/15) * pBackground->gray;
+ } else {
+ *red = (uch)pBackground->red;
+ *green = (uch)pBackground->green;
+ *blue = (uch)pBackground->blue;
+ }
+
+ return 0;
+}
+
+
+
+
+/* display_exponent == LUT_exponent * CRT_exponent */
+
+uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)
+{
+ double gamma;
+ png_uint_32 i, rowbytes;
+ png_bytepp row_pointers = NULL;
+
+
+ /* setjmp() must be called in every function that calls a PNG-reading
+ * libpng function */
+
+ if (setjmp(png_jmpbuf(png_ptr))) {
+ free(image_data);
+ image_data = NULL;
+ free(row_pointers);
+ row_pointers = NULL;
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ return NULL;
+ }
+
+
+ /* expand palette images to RGB, low-bit-depth grayscale images to 8 bits,
+ * transparency chunks to full alpha channel; strip 16-bit-per-sample
+ * images to 8 bits per sample; and convert grayscale to RGB[A] */
+
+ if (color_type == PNG_COLOR_TYPE_PALETTE)
+ png_set_expand(png_ptr);
+ if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+ png_set_expand(png_ptr);
+ if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+ png_set_expand(png_ptr);
+#ifdef PNG_READ_16_TO_8_SUPPORTED
+ if (bit_depth == 16)
+# ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+ png_set_scale_16(png_ptr);
+# else
+ png_set_strip_16(png_ptr);
+# endif
+#endif
+ if (color_type == PNG_COLOR_TYPE_GRAY ||
+ color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+ png_set_gray_to_rgb(png_ptr);
+
+
+ /* unlike the example in the libpng documentation, we have *no* idea where
+ * this file may have come from--so if it doesn't have a file gamma, don't
+ * do any correction ("do no harm") */
+
+ if (png_get_gAMA(png_ptr, info_ptr, &gamma))
+ png_set_gamma(png_ptr, display_exponent, gamma);
+
+
+ /* all transformations have been registered; now update info_ptr data,
+ * get rowbytes and channels, and allocate image memory */
+
+ png_read_update_info(png_ptr, info_ptr);
+
+ *pRowbytes = rowbytes = png_get_rowbytes(png_ptr, info_ptr);
+ *pChannels = (int)png_get_channels(png_ptr, info_ptr);
+
+ if ((image_data = (uch *)malloc(rowbytes*height)) == NULL) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ return NULL;
+ }
+ if ((row_pointers = (png_bytepp)malloc(height*sizeof(png_bytep))) == NULL) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ free(image_data);
+ image_data = NULL;
+ return NULL;
+ }
+
+ Trace((stderr, "readpng_get_image: channels = %d, rowbytes = %ld, height = %ld\n",
+ *pChannels, rowbytes, height));
+
+
+ /* set the individual row_pointers to point at the correct offsets */
+
+ for (i = 0; i < height; ++i)
+ row_pointers[i] = image_data + i*rowbytes;
+
+
+ /* now we can go ahead and just read the whole image */
+
+ png_read_image(png_ptr, row_pointers);
+
+
+ /* and we're done! (png_read_end() can be omitted if no processing of
+ * post-IDAT text/time/etc. is desired) */
+
+ free(row_pointers);
+ row_pointers = NULL;
+
+ png_read_end(png_ptr, NULL);
+
+ return image_data;
+}
+
+
+void readpng_cleanup(int free_image_data)
+{
+ if (free_image_data && image_data) {
+ free(image_data);
+ image_data = NULL;
+ }
+
+ if (png_ptr && info_ptr) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ png_ptr = NULL;
+ info_ptr = NULL;
+ }
+}
diff --git a/libpng/contrib/gregbook/readpng.h b/libpng/contrib/gregbook/readpng.h
new file mode 100644
index 0000000..fad9fe3
--- /dev/null
+++ b/libpng/contrib/gregbook/readpng.h
@@ -0,0 +1,88 @@
+/*---------------------------------------------------------------------------
+
+ rpng - simple PNG display program readpng.h
+
+ ---------------------------------------------------------------------------
+
+ Copyright (c) 1998-2007 Greg Roelofs. All rights reserved.
+
+ This software is provided "as is," without warranty of any kind,
+ express or implied. In no event shall the author or contributors
+ be held liable for any damages arising in any way from the use of
+ this software.
+
+ The contents of this file are DUAL-LICENSED. You may modify and/or
+ redistribute this software according to the terms of one of the
+ following two licenses (at your option):
+
+
+ LICENSE 1 ("BSD-like with advertising clause"):
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute
+ it freely, subject to the following restrictions:
+
+ 1. Redistributions of source code must retain the above copyright
+ notice, disclaimer, and this list of conditions.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, disclaimer, and this list of conditions in the documenta-
+ tion and/or other materials provided with the distribution.
+ 3. All advertising materials mentioning features or use of this
+ software must display the following acknowledgment:
+
+ This product includes software developed by Greg Roelofs
+ and contributors for the book, "PNG: The Definitive Guide,"
+ published by O'Reilly and Associates.
+
+
+ LICENSE 2 (GNU GPL v2 or later):
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ ---------------------------------------------------------------------------*/
+
+#ifndef TRUE
+# define TRUE 1
+# define FALSE 0
+#endif
+
+#ifndef MAX
+# define MAX(a,b) ((a) > (b)? (a) : (b))
+# define MIN(a,b) ((a) < (b)? (a) : (b))
+#endif
+
+#ifdef DEBUG
+# define Trace(x) {fprintf x ; fflush(stderr); fflush(stdout);}
+#else
+# define Trace(x) ;
+#endif
+
+typedef unsigned char uch;
+typedef unsigned short ush;
+typedef unsigned long ulg;
+
+
+/* prototypes for public functions in readpng.c */
+
+void readpng_version_info(void);
+
+int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight);
+
+int readpng_get_bgcolor(uch *bg_red, uch *bg_green, uch *bg_blue);
+
+uch *readpng_get_image(double display_exponent, int *pChannels,
+ ulg *pRowbytes);
+
+void readpng_cleanup(int free_image_data);
diff --git a/libpng/contrib/gregbook/readpng2.c b/libpng/contrib/gregbook/readpng2.c
new file mode 100644
index 0000000..a9e7ba5
--- /dev/null
+++ b/libpng/contrib/gregbook/readpng2.c
@@ -0,0 +1,520 @@
+/*---------------------------------------------------------------------------
+
+ rpng2 - progressive-model PNG display program readpng2.c
+
+ ---------------------------------------------------------------------------
+
+ Copyright (c) 1998-2015 Greg Roelofs. All rights reserved.
+
+ This software is provided "as is," without warranty of any kind,
+ express or implied. In no event shall the author or contributors
+ be held liable for any damages arising in any way from the use of
+ this software.
+
+ The contents of this file are DUAL-LICENSED. You may modify and/or
+ redistribute this software according to the terms of one of the
+ following two licenses (at your option):
+
+
+ LICENSE 1 ("BSD-like with advertising clause"):
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute
+ it freely, subject to the following restrictions:
+
+ 1. Redistributions of source code must retain the above copyright
+ notice, disclaimer, and this list of conditions.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, disclaimer, and this list of conditions in the documenta-
+ tion and/or other materials provided with the distribution.
+ 3. All advertising materials mentioning features or use of this
+ software must display the following acknowledgment:
+
+ This product includes software developed by Greg Roelofs
+ and contributors for the book, "PNG: The Definitive Guide,"
+ published by O'Reilly and Associates.
+
+
+ LICENSE 2 (GNU GPL v2 or later):
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ ---------------------------------------------------------------------------
+
+ Changelog:
+ %RDATE% - Check return value of png_get_bKGD() (Glenn R-P)
+
+ ---------------------------------------------------------------------------*/
+
+
+#include <stdlib.h> /* for exit() prototype */
+#include <setjmp.h>
+
+#include <zlib.h>
+#include "png.h" /* libpng header from the local directory */
+#include "readpng2.h" /* typedefs, common macros, public prototypes */
+
+
+/* local prototypes */
+
+static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr);
+static void readpng2_row_callback(png_structp png_ptr, png_bytep new_row,
+ png_uint_32 row_num, int pass);
+static void readpng2_end_callback(png_structp png_ptr, png_infop info_ptr);
+static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg);
+static void readpng2_warning_handler(png_structp png_ptr, png_const_charp msg);
+
+
+
+
+void readpng2_version_info(void)
+{
+ fprintf(stderr, " Compiled with libpng %s; using libpng %s\n",
+ PNG_LIBPNG_VER_STRING, png_libpng_ver);
+
+ fprintf(stderr, " and with zlib %s; using zlib %s.\n",
+ ZLIB_VERSION, zlib_version);
+}
+
+
+
+
+int readpng2_check_sig(uch *sig, int num)
+{
+ return !png_sig_cmp(sig, 0, num);
+}
+
+
+
+
+/* returns 0 for success, 2 for libpng problem, 4 for out of memory */
+
+int readpng2_init(mainprog_info *mainprog_ptr)
+{
+ png_structp png_ptr; /* note: temporary variables! */
+ png_infop info_ptr;
+
+
+ /* could also replace libpng warning-handler (final NULL), but no need: */
+
+ png_ptr = png_create_read_struct(png_get_libpng_ver(NULL), mainprog_ptr,
+ readpng2_error_handler, readpng2_warning_handler);
+ if (!png_ptr)
+ return 4; /* out of memory */
+
+ info_ptr = png_create_info_struct(png_ptr);
+ if (!info_ptr) {
+ png_destroy_read_struct(&png_ptr, NULL, NULL);
+ return 4; /* out of memory */
+ }
+
+
+ /* we could create a second info struct here (end_info), but it's only
+ * useful if we want to keep pre- and post-IDAT chunk info separated
+ * (mainly for PNG-aware image editors and converters) */
+
+
+ /* setjmp() must be called in every function that calls a PNG-reading
+ * libpng function, unless an alternate error handler was installed--
+ * but compatible error handlers must either use longjmp() themselves
+ * (as in this program) or exit immediately, so here we are: */
+
+ if (setjmp(mainprog_ptr->jmpbuf)) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ return 2;
+ }
+
+
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+ /* prepare the reader to ignore all recognized chunks whose data won't be
+ * used, i.e., all chunks recognized by libpng except for IHDR, PLTE, IDAT,
+ * IEND, tRNS, bKGD, gAMA, and sRGB (small performance improvement) */
+ {
+ /* These byte strings were copied from png.h. If a future version
+ * of readpng2.c recognizes more chunks, add them to this list.
+ */
+ static PNG_CONST png_byte chunks_to_process[] = {
+ 98, 75, 71, 68, '\0', /* bKGD */
+ 103, 65, 77, 65, '\0', /* gAMA */
+ 115, 82, 71, 66, '\0', /* sRGB */
+ };
+
+ /* Ignore all chunks except for IHDR, PLTE, tRNS, IDAT, and IEND */
+ png_set_keep_unknown_chunks(png_ptr, -1 /* PNG_HANDLE_CHUNK_NEVER */,
+ NULL, -1);
+
+ /* But do not ignore chunks in the "chunks_to_process" list */
+ png_set_keep_unknown_chunks(png_ptr,
+ 0 /* PNG_HANDLE_CHUNK_AS_DEFAULT */, chunks_to_process,
+ sizeof(chunks_to_process)/5);
+ }
+#endif /* PNG_HANDLE_AS_UNKNOWN_SUPPORTED */
+
+
+ /* instead of doing png_init_io() here, now we set up our callback
+ * functions for progressive decoding */
+
+ png_set_progressive_read_fn(png_ptr, mainprog_ptr,
+ readpng2_info_callback, readpng2_row_callback, readpng2_end_callback);
+
+
+ /* make sure we save our pointers for use in readpng2_decode_data() */
+
+ mainprog_ptr->png_ptr = png_ptr;
+ mainprog_ptr->info_ptr = info_ptr;
+
+
+ /* and that's all there is to initialization */
+
+ return 0;
+}
+
+
+
+
+/* returns 0 for success, 2 for libpng (longjmp) problem */
+
+int readpng2_decode_data(mainprog_info *mainprog_ptr, uch *rawbuf, ulg length)
+{
+ png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+ png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+ /* setjmp() must be called in every function that calls a PNG-reading
+ * libpng function */
+
+ if (setjmp(mainprog_ptr->jmpbuf)) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ mainprog_ptr->png_ptr = NULL;
+ mainprog_ptr->info_ptr = NULL;
+ return 2;
+ }
+
+
+ /* hand off the next chunk of input data to libpng for decoding */
+
+ png_process_data(png_ptr, info_ptr, rawbuf, length);
+
+ return 0;
+}
+
+
+
+
+static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr)
+{
+ mainprog_info *mainprog_ptr;
+ int color_type, bit_depth;
+ png_uint_32 width, height;
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ double gamma;
+#else
+ png_fixed_point gamma;
+#endif
+
+
+ /* setjmp() doesn't make sense here, because we'd either have to exit(),
+ * longjmp() ourselves, or return control to libpng, which doesn't want
+ * to see us again. By not doing anything here, libpng will instead jump
+ * to readpng2_decode_data(), which can return an error value to the main
+ * program. */
+
+
+ /* retrieve the pointer to our special-purpose struct, using the png_ptr
+ * that libpng passed back to us (i.e., not a global this time--there's
+ * no real difference for a single image, but for a multithreaded browser
+ * decoding several PNG images at the same time, one needs to avoid mixing
+ * up different images' structs) */
+
+ mainprog_ptr = png_get_progressive_ptr(png_ptr);
+
+ if (mainprog_ptr == NULL) { /* we be hosed */
+ fprintf(stderr,
+ "readpng2 error: main struct not recoverable in info_callback.\n");
+ fflush(stderr);
+ return;
+ /*
+ * Alternatively, we could call our error-handler just like libpng
+ * does, which would effectively terminate the program. Since this
+ * can only happen if png_ptr gets redirected somewhere odd or the
+ * main PNG struct gets wiped, we're probably toast anyway. (If
+ * png_ptr itself is NULL, we would not have been called.)
+ */
+ }
+
+
+ /* this is just like in the non-progressive case */
+
+ png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+ NULL, NULL, NULL);
+ mainprog_ptr->width = (ulg)width;
+ mainprog_ptr->height = (ulg)height;
+
+
+ /* since we know we've read all of the PNG file's "header" (i.e., up
+ * to IDAT), we can check for a background color here */
+
+ if (mainprog_ptr->need_bgcolor)
+ {
+ png_color_16p pBackground;
+
+ /* it is not obvious from the libpng documentation, but this function
+ * takes a pointer to a pointer, and it always returns valid red,
+ * green and blue values, regardless of color_type: */
+ if (png_get_bKGD(png_ptr, info_ptr, &pBackground))
+ {
+
+ /* however, it always returns the raw bKGD data, regardless of any
+ * bit-depth transformations, so check depth and adjust if necessary
+ */
+ if (bit_depth == 16) {
+ mainprog_ptr->bg_red = pBackground->red >> 8;
+ mainprog_ptr->bg_green = pBackground->green >> 8;
+ mainprog_ptr->bg_blue = pBackground->blue >> 8;
+ } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
+ if (bit_depth == 1)
+ mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+ mainprog_ptr->bg_blue = pBackground->gray? 255 : 0;
+ else if (bit_depth == 2)
+ mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+ mainprog_ptr->bg_blue = (255/3) * pBackground->gray;
+ else /* bit_depth == 4 */
+ mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+ mainprog_ptr->bg_blue = (255/15) * pBackground->gray;
+ } else {
+ mainprog_ptr->bg_red = (uch)pBackground->red;
+ mainprog_ptr->bg_green = (uch)pBackground->green;
+ mainprog_ptr->bg_blue = (uch)pBackground->blue;
+ }
+ }
+ }
+
+
+ /* as before, let libpng expand palette images to RGB, low-bit-depth
+ * grayscale images to 8 bits, transparency chunks to full alpha channel;
+ * strip 16-bit-per-sample images to 8 bits per sample; and convert
+ * grayscale to RGB[A] */
+
+ if (color_type == PNG_COLOR_TYPE_PALETTE)
+ png_set_expand(png_ptr);
+ if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+ png_set_expand(png_ptr);
+ if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+ png_set_expand(png_ptr);
+#ifdef PNG_READ_16_TO_8_SUPPORTED
+ if (bit_depth == 16)
+# ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+ png_set_scale_16(png_ptr);
+# else
+ png_set_strip_16(png_ptr);
+# endif
+#endif
+ if (color_type == PNG_COLOR_TYPE_GRAY ||
+ color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+ png_set_gray_to_rgb(png_ptr);
+
+
+ /* Unlike the basic viewer, which was designed to operate on local files,
+ * this program is intended to simulate a web browser--even though we
+ * actually read from a local file, too. But because we are pretending
+ * that most of the images originate on the Internet, we follow the recom-
+ * mendation of the sRGB proposal and treat unlabelled images (no gAMA
+ * chunk) as existing in the sRGB color space. That is, we assume that
+ * such images have a file gamma of 0.45455, which corresponds to a PC-like
+ * display system. This change in assumptions will have no effect on a
+ * PC-like system, but on a Mac, SGI, NeXT or other system with a non-
+ * identity lookup table, it will darken unlabelled images, which effec-
+ * tively favors images from PC-like systems over those originating on
+ * the local platform. Note that mainprog_ptr->display_exponent is the
+ * "gamma" value for the entire display system, i.e., the product of
+ * LUT_exponent and CRT_exponent. */
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+ if (png_get_gAMA(png_ptr, info_ptr, &gamma))
+ png_set_gamma(png_ptr, mainprog_ptr->display_exponent, gamma);
+ else
+ png_set_gamma(png_ptr, mainprog_ptr->display_exponent, 0.45455);
+#else
+ if (png_get_gAMA_fixed(png_ptr, info_ptr, &gamma))
+ png_set_gamma_fixed(png_ptr,
+ (png_fixed_point)(100000*mainprog_ptr->display_exponent+.5), gamma);
+ else
+ png_set_gamma_fixed(png_ptr,
+ (png_fixed_point)(100000*mainprog_ptr->display_exponent+.5), 45455);
+#endif
+
+ /* we'll let libpng expand interlaced images, too */
+
+ mainprog_ptr->passes = png_set_interlace_handling(png_ptr);
+
+
+ /* all transformations have been registered; now update info_ptr data and
+ * then get rowbytes and channels */
+
+ png_read_update_info(png_ptr, info_ptr);
+
+ mainprog_ptr->rowbytes = (int)png_get_rowbytes(png_ptr, info_ptr);
+ mainprog_ptr->channels = png_get_channels(png_ptr, info_ptr);
+
+
+ /* Call the main program to allocate memory for the image buffer and
+ * initialize windows and whatnot. (The old-style function-pointer
+ * invocation is used for compatibility with a few supposedly ANSI
+ * compilers that nevertheless barf on "fn_ptr()"-style syntax.) */
+
+ (*mainprog_ptr->mainprog_init)();
+
+
+ /* and that takes care of initialization */
+
+ return;
+}
+
+
+
+
+
+static void readpng2_row_callback(png_structp png_ptr, png_bytep new_row,
+ png_uint_32 row_num, int pass)
+{
+ mainprog_info *mainprog_ptr;
+
+
+ /* first check whether the row differs from the previous pass; if not,
+ * nothing to combine or display */
+
+ if (!new_row)
+ return;
+
+
+ /* retrieve the pointer to our special-purpose struct so we can access
+ * the old rows and image-display callback function */
+
+ mainprog_ptr = png_get_progressive_ptr(png_ptr);
+
+
+ /* save the pass number for optional use by the front end */
+
+ mainprog_ptr->pass = pass;
+
+
+ /* have libpng either combine the new row data with the existing row data
+ * from previous passes (if interlaced) or else just copy the new row
+ * into the main program's image buffer */
+
+ png_progressive_combine_row(png_ptr, mainprog_ptr->row_pointers[row_num],
+ new_row);
+
+
+ /* finally, call the display routine in the main program with the number
+ * of the row we just updated */
+
+ (*mainprog_ptr->mainprog_display_row)(row_num);
+
+
+ /* and we're ready for more */
+
+ return;
+}
+
+
+
+
+
+static void readpng2_end_callback(png_structp png_ptr, png_infop info_ptr)
+{
+ mainprog_info *mainprog_ptr;
+
+
+ /* retrieve the pointer to our special-purpose struct */
+
+ mainprog_ptr = png_get_progressive_ptr(png_ptr);
+
+
+ /* let the main program know that it should flush any buffered image
+ * data to the display now and set a "done" flag or whatever, but note
+ * that it SHOULD NOT DESTROY THE PNG STRUCTS YET--in other words, do
+ * NOT call readpng2_cleanup() either here or in the finish_display()
+ * routine; wait until control returns to the main program via
+ * readpng2_decode_data() */
+
+ (*mainprog_ptr->mainprog_finish_display)();
+
+
+ /* all done */
+
+ (void)info_ptr; /* Unused */
+
+ return;
+}
+
+
+
+
+
+void readpng2_cleanup(mainprog_info *mainprog_ptr)
+{
+ png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+ png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+ if (png_ptr && info_ptr)
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+
+ mainprog_ptr->png_ptr = NULL;
+ mainprog_ptr->info_ptr = NULL;
+}
+
+
+static void readpng2_warning_handler(png_structp png_ptr, png_const_charp msg)
+{
+ fprintf(stderr, "readpng2 libpng warning: %s\n", msg);
+ fflush(stderr);
+ (void)png_ptr; /* Unused */
+}
+
+
+static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg)
+{
+ mainprog_info *mainprog_ptr;
+
+ /* This function, aside from the extra step of retrieving the "error
+ * pointer" (below) and the fact that it exists within the application
+ * rather than within libpng, is essentially identical to libpng's
+ * default error handler. The second point is critical: since both
+ * setjmp() and longjmp() are called from the same code, they are
+ * guaranteed to have compatible notions of how big a jmp_buf is,
+ * regardless of whether _BSD_SOURCE or anything else has (or has not)
+ * been defined. */
+
+ fprintf(stderr, "readpng2 libpng error: %s\n", msg);
+ fflush(stderr);
+
+ mainprog_ptr = png_get_error_ptr(png_ptr);
+ if (mainprog_ptr == NULL) { /* we are completely hosed now */
+ fprintf(stderr,
+ "readpng2 severe error: jmpbuf not recoverable; terminating.\n");
+ fflush(stderr);
+ exit(99);
+ }
+
+ /* Now we have our data structure we can use the information in it
+ * to return control to our own higher level code (all the points
+ * where 'setjmp' is called in this file.) This will work with other
+ * error handling mechanisms as well - libpng always calls png_error
+ * when it can proceed no further, thus, so long as the error handler
+ * is intercepted, application code can do its own error recovery.
+ */
+ longjmp(mainprog_ptr->jmpbuf, 1);
+}
diff --git a/libpng/contrib/gregbook/readpng2.h b/libpng/contrib/gregbook/readpng2.h
new file mode 100644
index 0000000..6b3660d
--- /dev/null
+++ b/libpng/contrib/gregbook/readpng2.h
@@ -0,0 +1,116 @@
+/*---------------------------------------------------------------------------
+
+ rpng2 - progressive-model PNG display program readpng2.h
+
+ ---------------------------------------------------------------------------
+
+ Copyright (c) 1998-2008 Greg Roelofs. All rights reserved.
+
+ This software is provided "as is," without warranty of any kind,
+ express or implied. In no event shall the author or contributors
+ be held liable for any damages arising in any way from the use of
+ this software.
+
+ The contents of this file are DUAL-LICENSED. You may modify and/or
+ redistribute this software according to the terms of one of the
+ following two licenses (at your option):
+
+
+ LICENSE 1 ("BSD-like with advertising clause"):
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute
+ it freely, subject to the following restrictions:
+
+ 1. Redistributions of source code must retain the above copyright
+ notice, disclaimer, and this list of conditions.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, disclaimer, and this list of conditions in the documenta-
+ tion and/or other materials provided with the distribution.
+ 3. All advertising materials mentioning features or use of this
+ software must display the following acknowledgment:
+
+ This product includes software developed by Greg Roelofs
+ and contributors for the book, "PNG: The Definitive Guide,"
+ published by O'Reilly and Associates.
+
+
+ LICENSE 2 (GNU GPL v2 or later):
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ ---------------------------------------------------------------------------*/
+
+#ifndef TRUE
+# define TRUE 1
+# define FALSE 0
+#endif
+
+#ifndef MAX
+# define MAX(a,b) ((a) > (b)? (a) : (b))
+# define MIN(a,b) ((a) < (b)? (a) : (b))
+#endif
+
+#ifdef DEBUG
+# define Trace(x) {fprintf x ; fflush(stderr); fflush(stdout);}
+#else
+# define Trace(x) ;
+#endif
+
+enum rpng2_states {
+ kPreInit = 0,
+ kWindowInit,
+ kDone
+};
+
+typedef unsigned char uch;
+typedef unsigned short ush;
+typedef unsigned long ulg;
+
+typedef struct _mainprog_info {
+ double display_exponent;
+ ulg width;
+ ulg height;
+ void *png_ptr;
+ void *info_ptr;
+ void (*mainprog_init)(void);
+ void (*mainprog_display_row)(ulg row_num);
+ void (*mainprog_finish_display)(void);
+ uch *image_data;
+ uch **row_pointers;
+ jmp_buf jmpbuf;
+ int passes; /* not used */
+ int pass;
+ int rowbytes;
+ int channels;
+ int need_bgcolor;
+ int state;
+ uch bg_red;
+ uch bg_green;
+ uch bg_blue;
+} mainprog_info;
+
+
+/* prototypes for public functions in readpng2.c */
+
+void readpng2_version_info(void);
+
+int readpng2_check_sig(uch *sig, int num);
+
+int readpng2_init(mainprog_info *mainprog_ptr);
+
+int readpng2_decode_data(mainprog_info *mainprog_ptr, uch *rawbuf, ulg length);
+
+void readpng2_cleanup(mainprog_info *mainprog_ptr);
diff --git a/libpng/contrib/gregbook/readppm.c b/libpng/contrib/gregbook/readppm.c
new file mode 100644
index 0000000..7fefc39
--- /dev/null
+++ b/libpng/contrib/gregbook/readppm.c
@@ -0,0 +1,183 @@
+/*---------------------------------------------------------------------------
+
+ rpng - simple PNG display program readppm.c
+
+ ---------------------------------------------------------------------------
+
+ This is a special-purpose replacement for readpng.c that allows binary
+ PPM files to be used in place of PNG images.
+
+ ---------------------------------------------------------------------------
+
+ Copyright (c) 1998-2007 Greg Roelofs. All rights reserved.
+
+ This software is provided "as is," without warranty of any kind,
+ express or implied. In no event shall the author or contributors
+ be held liable for any damages arising in any way from the use of
+ this software.
+
+ The contents of this file are DUAL-LICENSED. You may modify and/or
+ redistribute this software according to the terms of one of the
+ following two licenses (at your option):
+
+
+ LICENSE 1 ("BSD-like with advertising clause"):
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute
+ it freely, subject to the following restrictions:
+
+ 1. Redistributions of source code must retain the above copyright
+ notice, disclaimer, and this list of conditions.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, disclaimer, and this list of conditions in the documenta-
+ tion and/or other materials provided with the distribution.
+ 3. All advertising materials mentioning features or use of this
+ software must display the following acknowledgment:
+
+ This product includes software developed by Greg Roelofs
+ and contributors for the book, "PNG: The Definitive Guide,"
+ published by O'Reilly and Associates.
+
+
+ LICENSE 2 (GNU GPL v2 or later):
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ ---------------------------------------------------------------------------*/
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "readpng.h" /* typedefs, common macros, public prototypes */
+
+
+ulg width, height;
+int bit_depth, color_type, channels;
+uch *image_data = NULL;
+FILE *saved_infile;
+
+
+void readpng_version_info()
+{
+ fprintf(stderr, " Compiled without libpng, zlib or PBMPLUS/NetPBM.\n");
+}
+
+
+/* return value = 0 for success, 1 for bad sig, 2 for bad IHDR, 4 for no mem */
+
+int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight)
+{
+ static uch ppmline[256];
+ int maxval;
+
+
+ saved_infile = infile;
+
+ fgets(ppmline, 256, infile);
+ if (ppmline[0] != 'P' || ppmline[1] != '6') {
+ fprintf(stderr, "ERROR: not a PPM file\n");
+ return 1;
+ }
+ /* possible color types: P5 = grayscale (0), P6 = RGB (2), P8 = RGBA (6) */
+ if (ppmline[1] == '6') {
+ color_type = 2;
+ channels = 3;
+ } else if (ppmline[1] == '8') {
+ color_type = 6;
+ channels = 4;
+ } else /* if (ppmline[1] == '5') */ {
+ color_type = 0;
+ channels = 1;
+ }
+
+ do {
+ fgets(ppmline, 256, infile);
+ } while (ppmline[0] == '#');
+ sscanf(ppmline, "%lu %lu", &width, &height);
+
+ do {
+ fgets(ppmline, 256, infile);
+ } while (ppmline[0] == '#');
+ sscanf(ppmline, "%d", &maxval);
+ if (maxval != 255) {
+ fprintf(stderr, "ERROR: maxval = %d\n", maxval);
+ return 2;
+ }
+ bit_depth = 8;
+
+ *pWidth = width;
+ *pHeight = height;
+
+ return 0;
+}
+
+
+
+
+/* returns 0 if succeeds, 1 if fails due to no bKGD chunk, 2 if libpng error;
+ * scales values to 8-bit if necessary */
+
+int readpng_get_bgcolor(uch *red, uch *green, uch *blue)
+{
+ return 1;
+}
+
+
+
+
+/* display_exponent == LUT_exponent * CRT_exponent */
+
+uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)
+{
+ ulg rowbytes;
+
+
+ /* expand palette images to RGB, low-bit-depth grayscale images to 8 bits,
+ * transparency chunks to full alpha channel; strip 16-bit-per-sample
+ * images to 8 bits per sample; and convert grayscale to RGB[A] */
+
+ /* GRR WARNING: grayscale needs to be expanded and channels reset! */
+
+ *pRowbytes = rowbytes = channels*width;
+ *pChannels = channels;
+
+ if ((image_data = (uch *)malloc(rowbytes*height)) == NULL) {
+ return NULL;
+ }
+
+ Trace((stderr, "readpng_get_image: rowbytes = %ld, height = %ld\n", rowbytes, height));
+
+
+ /* now we can go ahead and just read the whole image */
+
+ if (fread(image_data, 1L, rowbytes*height, saved_infile) <
+ rowbytes*height) {
+ free (image_data);
+ image_data = NULL;
+ return NULL;
+ }
+
+ return image_data;
+}
+
+
+void readpng_cleanup(int free_image_data)
+{
+ if (free_image_data && image_data) {
+ free(image_data);
+ image_data = NULL;
+ }
+}
diff --git a/libpng/contrib/gregbook/rpng-win.c b/libpng/contrib/gregbook/rpng-win.c
new file mode 100644
index 0000000..f53ddc8
--- /dev/null
+++ b/libpng/contrib/gregbook/rpng-win.c
@@ -0,0 +1,728 @@
+/*---------------------------------------------------------------------------
+
+ rpng - simple PNG display program rpng-win.c
+
+ This program decodes and displays PNG images, with gamma correction and
+ optionally with a user-specified background color (in case the image has
+ transparency). It is very nearly the most basic PNG viewer possible.
+ This version is for 32-bit Windows; it may compile under 16-bit Windows
+ with a little tweaking (or maybe not).
+
+ to do:
+ - handle quoted command-line args (especially filenames with spaces)
+ - have minimum window width: oh well
+ - use %.1023s to simplify truncation of title-bar string?
+
+ ---------------------------------------------------------------------------
+
+ Changelog:
+ - 1.00: initial public release
+ - 1.01: modified to allow abbreviated options; fixed long/ulong mis-
+ match; switched to png_jmpbuf() macro
+ - 1.02: added extra set of parentheses to png_jmpbuf() macro; fixed
+ command-line parsing bug
+ - 1.10: enabled "message window"/console (thanks to David Geldreich)
+ - 2.00: dual-licensed (added GNU GPL)
+ - 2.01: fixed improper display of usage screen on PNG error(s)
+
+ ---------------------------------------------------------------------------
+
+ Copyright (c) 1998-2008 Greg Roelofs. All rights reserved.
+
+ This software is provided "as is," without warranty of any kind,
+ express or implied. In no event shall the author or contributors
+ be held liable for any damages arising in any way from the use of
+ this software.
+
+ The contents of this file are DUAL-LICENSED. You may modify and/or
+ redistribute this software according to the terms of one of the
+ following two licenses (at your option):
+
+
+ LICENSE 1 ("BSD-like with advertising clause"):
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute
+ it freely, subject to the following restrictions:
+
+ 1. Redistributions of source code must retain the above copyright
+ notice, disclaimer, and this list of conditions.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, disclaimer, and this list of conditions in the documenta-
+ tion and/or other materials provided with the distribution.
+ 3. All advertising materials mentioning features or use of this
+ software must display the following acknowledgment:
+
+ This product includes software developed by Greg Roelofs
+ and contributors for the book, "PNG: The Definitive Guide,"
+ published by O'Reilly and Associates.
+
+
+ LICENSE 2 (GNU GPL v2 or later):
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ ---------------------------------------------------------------------------*/
+
+#define PROGNAME "rpng-win"
+#define LONGNAME "Simple PNG Viewer for Windows"
+#define VERSION "2.01 of 16 March 2008"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <windows.h>
+#ifdef __CYGWIN__
+/* getch replacement. Turns out, we don't really need this,
+ * but leave it here if we ever enable any of the uses of
+ * _getch in the main code
+ */
+#include <unistd.h>
+#include <termio.h>
+#include <sys/ioctl.h>
+int repl_getch( void )
+{
+ char ch;
+ int fd = fileno(stdin);
+ struct termio old_tty, new_tty;
+
+ ioctl(fd, TCGETA, &old_tty);
+ new_tty = old_tty;
+ new_tty.c_lflag &= ~(ICANON | ECHO | ISIG);
+ ioctl(fd, TCSETA, &new_tty);
+ fread(&ch, 1, sizeof(ch), stdin);
+ ioctl(fd, TCSETA, &old_tty);
+
+ return ch;
+}
+#define _getch repl_getch
+#else
+#include <conio.h> /* only for _getch() */
+#endif
+
+/* #define DEBUG : this enables the Trace() macros */
+
+#include "readpng.h" /* typedefs, common macros, readpng prototypes */
+
+
+/* could just include png.h, but this macro is the only thing we need
+ * (name and typedefs changed to local versions); note that side effects
+ * only happen with alpha (which could easily be avoided with
+ * "ush acopy = (alpha);") */
+
+#define alpha_composite(composite, fg, alpha, bg) { \
+ ush temp = ((ush)(fg)*(ush)(alpha) + \
+ (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128); \
+ (composite) = (uch)((temp + (temp >> 8)) >> 8); \
+}
+
+
+/* local prototypes */
+static int rpng_win_create_window(HINSTANCE hInst, int showmode);
+static int rpng_win_display_image(void);
+static void rpng_win_cleanup(void);
+LRESULT CALLBACK rpng_win_wndproc(HWND, UINT, WPARAM, LPARAM);
+
+
+static char titlebar[1024];
+static char *progname = PROGNAME;
+static char *appname = LONGNAME;
+static char *filename;
+static FILE *infile;
+
+static char *bgstr;
+static uch bg_red=0, bg_green=0, bg_blue=0;
+
+static double display_exponent;
+
+static ulg image_width, image_height, image_rowbytes;
+static int image_channels;
+static uch *image_data;
+
+/* Windows-specific variables */
+static ulg wimage_rowbytes;
+static uch *dib;
+static uch *wimage_data;
+static BITMAPINFOHEADER *bmih;
+
+static HWND global_hwnd;
+
+
+
+
+int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
+{
+ char *args[1024]; /* arbitrary limit, but should suffice */
+ char *p, *q, **argv = args;
+ int argc = 0;
+ int rc, alen, flen;
+ int error = 0;
+ int have_bg = FALSE;
+ double LUT_exponent; /* just the lookup table */
+ double CRT_exponent = 2.2; /* just the monitor */
+ double default_display_exponent; /* whole display system */
+ MSG msg;
+
+
+ filename = (char *)NULL;
+
+#ifndef __CYGWIN__
+ /* First reenable console output, which normally goes to the bit bucket
+ * for windowed apps. Closing the console window will terminate the
+ * app. Thanks to David.Geldreich@realviz.com for supplying the magical
+ * incantation. */
+
+ AllocConsole();
+ freopen("CONOUT$", "a", stderr);
+ freopen("CONOUT$", "a", stdout);
+#endif
+
+
+ /* Next set the default value for our display-system exponent, i.e.,
+ * the product of the CRT exponent and the exponent corresponding to
+ * the frame-buffer's lookup table (LUT), if any. This is not an
+ * exhaustive list of LUT values (e.g., OpenStep has a lot of weird
+ * ones), but it should cover 99% of the current possibilities. And
+ * yes, these ifdefs are completely wasted in a Windows program... */
+
+#if defined(NeXT)
+ LUT_exponent = 1.0 / 2.2;
+ /*
+ if (some_next_function_that_returns_gamma(&next_gamma))
+ LUT_exponent = 1.0 / next_gamma;
+ */
+#elif defined(sgi)
+ LUT_exponent = 1.0 / 1.7;
+ /* there doesn't seem to be any documented function to get the
+ * "gamma" value, so we do it the hard way */
+ infile = fopen("/etc/config/system.glGammaVal", "r");
+ if (infile) {
+ double sgi_gamma;
+
+ fgets(tmpline, 80, infile);
+ fclose(infile);
+ sgi_gamma = atof(tmpline);
+ if (sgi_gamma > 0.0)
+ LUT_exponent = 1.0 / sgi_gamma;
+ }
+#elif defined(Macintosh)
+ LUT_exponent = 1.8 / 2.61;
+ /*
+ if (some_mac_function_that_returns_gamma(&mac_gamma))
+ LUT_exponent = mac_gamma / 2.61;
+ */
+#else
+ LUT_exponent = 1.0; /* assume no LUT: most PCs */
+#endif
+
+ /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+ default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+ /* If the user has set the SCREEN_GAMMA environment variable as suggested
+ * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+ * use the default value we just calculated. Either way, the user may
+ * override this via a command-line option. */
+
+ if ((p = getenv("SCREEN_GAMMA")) != NULL)
+ display_exponent = atof(p);
+ else
+ display_exponent = default_display_exponent;
+
+
+ /* Windows really hates command lines, so we have to set up our own argv.
+ * Note that we do NOT bother with quoted arguments here, so don't use
+ * filenames with spaces in 'em! */
+
+ argv[argc++] = PROGNAME;
+ p = cmd;
+ for (;;) {
+ if (*p == ' ')
+ while (*++p == ' ')
+ ;
+ /* now p points at the first non-space after some spaces */
+ if (*p == '\0')
+ break; /* nothing after the spaces: done */
+ argv[argc++] = q = p;
+ while (*q && *q != ' ')
+ ++q;
+ /* now q points at a space or the end of the string */
+ if (*q == '\0')
+ break; /* last argv already terminated; quit */
+ *q = '\0'; /* change space to terminator */
+ p = q + 1;
+ }
+ argv[argc] = NULL; /* terminate the argv array itself */
+
+
+ /* Now parse the command line for options and the PNG filename. */
+
+ while (*++argv && !error) {
+ if (!strncmp(*argv, "-gamma", 2)) {
+ if (!*++argv)
+ ++error;
+ else {
+ display_exponent = atof(*argv);
+ if (display_exponent <= 0.0)
+ ++error;
+ }
+ } else if (!strncmp(*argv, "-bgcolor", 2)) {
+ if (!*++argv)
+ ++error;
+ else {
+ bgstr = *argv;
+ if (strlen(bgstr) != 7 || bgstr[0] != '#')
+ ++error;
+ else
+ have_bg = TRUE;
+ }
+ } else {
+ if (**argv != '-') {
+ filename = *argv;
+ if (argv[1]) /* shouldn't be any more args after filename */
+ ++error;
+ } else
+ ++error; /* not expecting any other options */
+ }
+ }
+
+ if (!filename)
+ ++error;
+
+
+ /* print usage screen if any errors up to this point */
+
+ if (error) {
+#ifndef __CYGWIN__
+ int ch;
+#endif
+
+ fprintf(stderr, "\n%s %s: %s\n\n", PROGNAME, VERSION, appname);
+ readpng_version_info();
+ fprintf(stderr, "\n"
+ "Usage: %s [-gamma exp] [-bgcolor bg] file.png\n"
+ " exp \ttransfer-function exponent (``gamma'') of the display\n"
+ "\t\t system in floating-point format (e.g., ``%.1f''); equal\n"
+ "\t\t to the product of the lookup-table exponent (varies)\n"
+ "\t\t and the CRT exponent (usually 2.2); must be positive\n"
+ " bg \tdesired background color in 7-character hex RGB format\n"
+ "\t\t (e.g., ``#ff7700'' for orange: same as HTML colors);\n"
+ "\t\t used with transparent images\n"
+ "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
+#ifndef __CYGWIN__
+ "Press Q or Esc to quit this usage screen.\n"
+#endif
+ "\n", PROGNAME, default_display_exponent);
+#ifndef __CYGWIN__
+ do
+ ch = _getch();
+ while (ch != 'q' && ch != 'Q' && ch != 0x1B);
+#endif
+ exit(1);
+ }
+
+
+ if (!(infile = fopen(filename, "rb"))) {
+ fprintf(stderr, PROGNAME ": can't open PNG file [%s]\n", filename);
+ ++error;
+ } else {
+ if ((rc = readpng_init(infile, &image_width, &image_height)) != 0) {
+ switch (rc) {
+ case 1:
+ fprintf(stderr, PROGNAME
+ ": [%s] is not a PNG file: incorrect signature\n",
+ filename);
+ break;
+ case 2:
+ fprintf(stderr, PROGNAME
+ ": [%s] has bad IHDR (libpng longjmp)\n", filename);
+ break;
+ case 4:
+ fprintf(stderr, PROGNAME ": insufficient memory\n");
+ break;
+ default:
+ fprintf(stderr, PROGNAME
+ ": unknown readpng_init() error\n");
+ break;
+ }
+ ++error;
+ }
+ if (error)
+ fclose(infile);
+ }
+
+
+ if (error) {
+#ifndef __CYGWIN__
+ int ch;
+#endif
+
+ fprintf(stderr, PROGNAME ": aborting.\n");
+#ifndef __CYGWIN__
+ do
+ ch = _getch();
+ while (ch != 'q' && ch != 'Q' && ch != 0x1B);
+#endif
+ exit(2);
+ } else {
+ fprintf(stderr, 