| /* $Id: zlib.h,v 1.1 1999/03/23 03:21:58 paulus Exp $ */ |
| |
| /* |
| * This file is derived from zlib.h and zconf.h from the zlib-0.95 |
| * distribution by Jean-loup Gailly and Mark Adler, with some additions |
| * by Paul Mackerras to aid in implementing Deflate compression and |
| * decompression for PPP packets. |
| */ |
| |
| /* zlib.h -- interface of the 'zlib' general purpose compression library |
| version 0.95, Aug 16th, 1995. |
| |
| Copyright (C) 1995 Jean-loup Gailly and Mark Adler |
| |
| This software is provided 'as-is', without any express or implied |
| warranty. In no event will the authors be held liable for any damages |
| arising from the use of this software. |
| |
| 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. The origin of this software must not be misrepresented; you must not |
| claim that you wrote the original software. If you use this software |
| in a product, an acknowledgment in the product documentation would be |
| appreciated but is not required. |
| 2. Altered source versions must be plainly marked as such, and must not be |
| misrepresented as being the original software. |
| 3. This notice may not be removed or altered from any source distribution. |
| |
| Jean-loup Gailly Mark Adler |
| gzip@prep.ai.mit.edu madler@alumni.caltech.edu |
| */ |
| |
| #ifndef _ZLIB_H |
| #define _ZLIB_H |
| |
| /* #include "zconf.h" */ /* included directly here */ |
| |
| /* zconf.h -- configuration of the zlib compression library |
| * Copyright (C) 1995 Jean-loup Gailly. |
| * For conditions of distribution and use, see copyright notice in zlib.h |
| */ |
| |
| /* From: zconf.h,v 1.12 1995/05/03 17:27:12 jloup Exp */ |
| |
| /* |
| The library does not install any signal handler. It is recommended to |
| add at least a handler for SIGSEGV when decompressing; the library checks |
| the consistency of the input data whenever possible but may go nuts |
| for some forms of corrupted input. |
| */ |
| |
| /* |
| * Compile with -DMAXSEG_64K if the alloc function cannot allocate more |
| * than 64k bytes at a time (needed on systems with 16-bit int). |
| * Compile with -DUNALIGNED_OK if it is OK to access shorts or ints |
| * at addresses which are not a multiple of their size. |
| * Under DOS, -DFAR=far or -DFAR=__far may be needed. |
| */ |
| |
| #ifndef STDC |
| # if defined(MSDOS) || defined(__STDC__) || defined(__cplusplus) |
| # define STDC |
| # endif |
| #endif |
| |
| #ifdef __MWERKS__ /* Metrowerks CodeWarrior declares fileno() in unix.h */ |
| # include <unix.h> |
| #endif |
| |
| /* Maximum value for memLevel in deflateInit2 */ |
| #ifndef MAX_MEM_LEVEL |
| # ifdef MAXSEG_64K |
| # define MAX_MEM_LEVEL 8 |
| # else |
| # define MAX_MEM_LEVEL 9 |
| # endif |
| #endif |
| |
| #ifndef FAR |
| # define FAR |
| #endif |
| |
| /* Maximum value for windowBits in deflateInit2 and inflateInit2 */ |
| #ifndef MAX_WBITS |
| # define MAX_WBITS 15 /* 32K LZ77 window */ |
| #endif |
| |
| /* The memory requirements for deflate are (in bytes): |
| 1 << (windowBits+2) + 1 << (memLevel+9) |
| that is: 128K for windowBits=15 + 128K for memLevel = 8 (default values) |
| plus a few kilobytes for small objects. For example, if you want to reduce |
| the default memory requirements from 256K to 128K, compile with |
| make CFLAGS="-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7" |
| Of course this will generally degrade compression (there's no free lunch). |
| |
| The memory requirements for inflate are (in bytes) 1 << windowBits |
| that is, 32K for windowBits=15 (default value) plus a few kilobytes |
| for small objects. |
| */ |
| |
| /* Type declarations */ |
| |
| #ifndef OF /* function prototypes */ |
| # ifdef STDC |
| # define OF(args) args |
| # else |
| # define OF(args) () |
| # endif |
| #endif |
| |
| typedef unsigned char Byte; /* 8 bits */ |
| typedef unsigned int uInt; /* 16 bits or more */ |
| typedef unsigned long uLong; /* 32 bits or more */ |
| |
| typedef Byte FAR Bytef; |
| typedef char FAR charf; |
| typedef int FAR intf; |
| typedef uInt FAR uIntf; |
| typedef uLong FAR uLongf; |
| |
| #ifdef STDC |
| typedef void FAR *voidpf; |
| typedef void *voidp; |
| #else |
| typedef Byte FAR *voidpf; |
| typedef Byte *voidp; |
| #endif |
| |
| /* end of original zconf.h */ |
| |
| #define ZLIB_VERSION "0.95P" |
| |
| /* |
| The 'zlib' compression library provides in-memory compression and |
| decompression functions, including integrity checks of the uncompressed |
| data. This version of the library supports only one compression method |
| (deflation) but other algorithms may be added later and will have the same |
| stream interface. |
| |
| For compression the application must provide the output buffer and |
| may optionally provide the input buffer for optimization. For decompression, |
| the application must provide the input buffer and may optionally provide |
| the output buffer for optimization. |
| |
| Compression can be done in a single step if the buffers are large |
| enough (for example if an input file is mmap'ed), or can be done by |
| repeated calls of the compression function. In the latter case, the |
| application must provide more input and/or consume the output |
| (providing more output space) before each call. |
| */ |
| |
| typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size)); |
| typedef void (*free_func) OF((voidpf opaque, voidpf address, uInt nbytes)); |
| |
| struct internal_state; |
| |
| typedef struct z_stream_s { |
| Bytef *next_in; /* next input byte */ |
| uInt avail_in; /* number of bytes available at next_in */ |
| uLong total_in; /* total nb of input bytes read so far */ |
| |
| Bytef *next_out; /* next output byte should be put there */ |
| uInt avail_out; /* remaining free space at next_out */ |
| uLong total_out; /* total nb of bytes output so far */ |
| |
| char *msg; /* last error message, NULL if no error */ |
| struct internal_state FAR *state; /* not visible by applications */ |
| |
| alloc_func zalloc; /* used to allocate the internal state */ |
| free_func zfree; /* used to free the internal state */ |
| voidp opaque; /* private data object passed to zalloc and zfree */ |
| |
| Byte data_type; /* best guess about the data type: ascii or binary */ |
| |
| } z_stream; |
| |
| /* |
| The application must update next_in and avail_in when avail_in has |
| dropped to zero. It must update next_out and avail_out when avail_out |
| has dropped to zero. The application must initialize zalloc, zfree and |
| opaque before calling the init function. All other fields are set by the |
| compression library and must not be updated by the application. |
| |
| The opaque value provided by the application will be passed as the first |
| parameter for calls of zalloc and zfree. This can be useful for custom |
| memory management. The compression library attaches no meaning to the |
| opaque value. |
| |
| zalloc must return Z_NULL if there is not enough memory for the object. |
| On 16-bit systems, the functions zalloc and zfree must be able to allocate |
| exactly 65536 bytes, but will not be required to allocate more than this |
| if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, |
| pointers returned by zalloc for objects of exactly 65536 bytes *must* |
| have their offset normalized to zero. The default allocation function |
| provided by this library ensures this (see zutil.c). To reduce memory |
| requirements and avoid any allocation of 64K objects, at the expense of |
| compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h). |
| |
| The fields total_in and total_out can be used for statistics or |
| progress reports. After compression, total_in holds the total size of |
| the uncompressed data and may be saved for use in the decompressor |
| (particularly if the decompressor wants to decompress everything in |
| a single step). |
| */ |
| |
| /* constants */ |
| |
| #define Z_NO_FLUSH 0 |
| #define Z_PARTIAL_FLUSH 1 |
| #define Z_FULL_FLUSH 2 |
| #define Z_SYNC_FLUSH 3 /* experimental: partial_flush + byte align */ |
| #define Z_FINISH 4 |
| #define Z_PACKET_FLUSH 5 |
| /* See deflate() below for the usage of these constants */ |
| |
| #define Z_OK 0 |
| #define Z_STREAM_END 1 |
| #define Z_ERRNO (-1) |
| #define Z_STREAM_ERROR (-2) |
| #define Z_DATA_ERROR (-3) |
| #define Z_MEM_ERROR (-4) |
| #define Z_BUF_ERROR (-5) |
| /* error codes for the compression/decompression functions */ |
| |
| #define Z_BEST_SPEED 1 |
| #define Z_BEST_COMPRESSION 9 |
| #define Z_DEFAULT_COMPRESSION (-1) |
| /* compression levels */ |
| |
| #define Z_FILTERED 1 |
| #define Z_HUFFMAN_ONLY 2 |
| #define Z_DEFAULT_STRATEGY 0 |
| |
| #define Z_BINARY 0 |
| #define Z_ASCII 1 |
| #define Z_UNKNOWN 2 |
| /* Used to set the data_type field */ |
| |
| #define Z_NULL 0 /* for initializing zalloc, zfree, opaque */ |
| |
| extern char *zlib_version; |
| /* The application can compare zlib_version and ZLIB_VERSION for consistency. |
| If the first character differs, the library code actually used is |
| not compatible with the zlib.h header file used by the application. |
| */ |
| |
| /* basic functions */ |
| |
| extern int deflateInit OF((z_stream *strm, int level)); |
| /* |
| Initializes the internal stream state for compression. The fields |
| zalloc, zfree and opaque must be initialized before by the caller. |
| If zalloc and zfree are set to Z_NULL, deflateInit updates them to |
| use default allocation functions. |
| |
| The compression level must be Z_DEFAULT_COMPRESSION, or between 1 and 9: |
| 1 gives best speed, 9 gives best compression. Z_DEFAULT_COMPRESSION requests |
| a default compromise between speed and compression (currently equivalent |
| to level 6). |
| |
| deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not |
| enough memory, Z_STREAM_ERROR if level is not a valid compression level. |
| msg is set to null if there is no error message. deflateInit does not |
| perform any compression: this will be done by deflate(). |
| */ |
| |
| |
| extern int deflate OF((z_stream *strm, int flush)); |
| /* |
| Performs one or both of the following actions: |
| |
| - Compress more input starting at next_in and update next_in and avail_in |
| accordingly. If not all input can be processed (because there is not |
| enough room in the output buffer), next_in and avail_in are updated and |
| processing will resume at this point for the next call of deflate(). |
| |
| - Provide more output starting at next_out and update next_out and avail_out |
| accordingly. This action is forced if the parameter flush is non zero. |
| Forcing flush frequently degrades the compression ratio, so this parameter |
| should be set only when necessary (in interactive applications). |
| Some output may be provided even if flush is not set. |
| |
| Before the call of deflate(), the application should ensure that at least |
| one of the actions is possible, by providing more input and/or consuming |
| more output, and updating avail_in or avail_out accordingly; avail_out |
| should never be zero before the call. The application can consume the |
| compressed output when it wants, for example when the output buffer is full |
| (avail_out == 0), or after each call of deflate(). |
| |
| If the parameter flush is set to Z_PARTIAL_FLUSH, the current compression |
| block is terminated and flushed to the output buffer so that the |
| decompressor can get all input data available so far. For method 9, a future |
| variant on method 8, the current block will be flushed but not terminated. |
| If flush is set to Z_FULL_FLUSH, the compression block is terminated, a |
| special marker is output and the compression dictionary is discarded; this |
| is useful to allow the decompressor to synchronize if one compressed block |
| has been damaged (see inflateSync below). Flushing degrades compression and |
| so should be used only when necessary. Using Z_FULL_FLUSH too often can |
| seriously degrade the compression. If deflate returns with avail_out == 0, |
| this function must be called again with the same value of the flush |
| parameter and more output space (updated avail_out), until the flush is |
| complete (deflate returns with non-zero avail_out). |
| |
| If the parameter flush is set to Z_PACKET_FLUSH, the compression |
| block is terminated, and a zero-length stored block is output, |
| omitting the length bytes (the effect of this is that the 3-bit type |
| code 000 for a stored block is output, and the output is then |
| byte-aligned). This is designed for use at the end of a PPP packet. |
| In addition, if the current compression block contains all the data |
| since the last Z_PACKET_FLUSH, it is never output as a stored block. |
| If the current compression block output as a static or dynamic block |
| would not be at least `minCompression' bytes smaller than the |
| original data, then nothing is output for that block. (The type |
| code for the zero-length stored block is still output, resulting in |
| a single zero byte being output for the whole packet.) |
| `MinCompression' is a parameter to deflateInit2, or 0 if deflateInit |
| is used. |
| |
| If the parameter flush is set to Z_FINISH, all pending input is processed, |
| all pending output is flushed and deflate returns with Z_STREAM_END if there |
| was enough output space; if deflate returns with Z_OK, this function must be |
| called again with Z_FINISH and more output space (updated avail_out) but no |
| more input data, until it returns with Z_STREAM_END or an error. After |
| deflate has returned Z_STREAM_END, the only possible operations on the |
| stream are deflateReset or deflateEnd. |
| |
| Z_FINISH can be used immediately after deflateInit if all the compression |
| is to be done in a single step. In this case, avail_out must be at least |
| 0.1% larger than avail_in plus 12 bytes. If deflate does not return |
| Z_STREAM_END, then it must be called again as described above. |
| |
| deflate() may update data_type if it can make a good guess about |
| the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered |
| binary. This field is only for information purposes and does not affect |
| the compression algorithm in any manner. |
| |
| deflate() returns Z_OK if some progress has been made (more input |
| processed or more output produced), Z_STREAM_END if all input has been |
| consumed and all output has been produced (only when flush is set to |
| Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example |
| if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible. |
| */ |
| |
| |
| extern int deflateEnd OF((z_stream *strm)); |
| /* |
| All dynamically allocated data structures for this stream are freed. |
| This function discards any unprocessed input and does not flush any |
| pending output. |
| |
| deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the |
| stream state was inconsistent. In the error case, msg may be set |
| but then points to a static string (which must not be deallocated). |
| */ |
| |
| |
| extern int inflateInit OF((z_stream *strm)); |
| /* |
| Initializes the internal stream state for decompression. The fields |
| zalloc and zfree must be initialized before by the caller. If zalloc and |
| zfree are set to Z_NULL, inflateInit updates them to use default allocation |
| functions. |
| |
| inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not |
| enough memory. msg is set to null if there is no error message. |
| inflateInit does not perform any decompression: this will be done by |
| inflate(). |
| */ |
| |
| |
| extern int inflate OF((z_stream *strm, int flush)); |
| /* |
| Performs one or both of the following actions: |
| |
| - Decompress more input starting at next_in and update next_in and avail_in |
| accordingly. If not all input can be processed (because there is not |
| enough room in the output buffer), next_in is updated and processing |
| will resume at this point for the next call of inflate(). |
| |
| - Provide more output starting at next_out and update next_out and avail_out |
| accordingly. inflate() always provides as much output as possible |
| (until there is no more input data or no more space in the output buffer). |
| |
| Before the call of inflate(), the application should ensure that at least |
| one of the actions is possible, by providing more input and/or consuming |
| more output, and updating the next_* and avail_* values accordingly. |
| The application can consume the uncompressed output when it wants, for |
| example when the output buffer is full (avail_out == 0), or after each |
| call of inflate(). |
| |
| If the parameter flush is set to Z_PARTIAL_FLUSH or Z_PACKET_FLUSH, |
| inflate flushes as much output as possible to the output buffer. The |
| flushing behavior of inflate is not specified for values of the flush |
| parameter other than Z_PARTIAL_FLUSH, Z_PACKET_FLUSH or Z_FINISH, but the |
| current implementation actually flushes as much output as possible |
| anyway. For Z_PACKET_FLUSH, inflate checks that once all the input data |
| has been consumed, it is expecting to see the length field of a stored |
| block; if not, it returns Z_DATA_ERROR. |
| |
| inflate() should normally be called until it returns Z_STREAM_END or an |
| error. However if all decompression is to be performed in a single step |
| (a single call of inflate), the parameter flush should be set to |
| Z_FINISH. In this case all pending input is processed and all pending |
| output is flushed; avail_out must be large enough to hold all the |
| uncompressed data. (The size of the uncompressed data may have been saved |
| by the compressor for this purpose.) The next operation on this stream must |
| be inflateEnd to deallocate the decompression state. The use of Z_FINISH |
| is never required, but can be used to inform inflate that a faster routine |
| may be used for the single inflate() call. |
| |
| inflate() returns Z_OK if some progress has been made (more input |
| processed or more output produced), Z_STREAM_END if the end of the |
| compressed data has been reached and all uncompressed output has been |
| produced, Z_DATA_ERROR if the input data was corrupted, Z_STREAM_ERROR if |
| the stream structure was inconsistent (for example if next_in or next_out |
| was NULL), Z_MEM_ERROR if there was not enough memory, Z_BUF_ERROR if no |
| progress is possible or if there was not enough room in the output buffer |
| when Z_FINISH is used. In the Z_DATA_ERROR case, the application may then |
| call inflateSync to look for a good compression block. */ |
| |
| |
| extern int inflateEnd OF((z_stream *strm)); |
| /* |
| All dynamically allocated data structures for this stream are freed. |
| This function discards any unprocessed input and does not flush any |
| pending output. |
| |
| inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state |
| was inconsistent. In the error case, msg may be set but then points to a |
| static string (which must not be deallocated). |
| */ |
| |
| /* advanced functions */ |
| |
| /* |
| The following functions are needed only in some special applications. |
| */ |
| |
| extern int deflateInit2 OF((z_stream *strm, |
| int level, |
| int method, |
| int windowBits, |
| int memLevel, |
| int strategy, |
| int minCompression)); |
| /* |
| This is another version of deflateInit with more compression options. The |
| fields next_in, zalloc and zfree must be initialized before by the caller. |
| |
| The method parameter is the compression method. It must be 8 in this |
| version of the library. (Method 9 will allow a 64K history buffer and |
| partial block flushes.) |
| |
| The windowBits parameter is the base two logarithm of the window size |
| (the size of the history buffer). It should be in the range 8..15 for this |
| version of the library (the value 16 will be allowed for method 9). Larger |
| values of this parameter result in better compression at the expense of |
| memory usage. The default value is 15 if deflateInit is used instead. |
| |
| The memLevel parameter specifies how much memory should be allocated |
| for the internal compression state. memLevel=1 uses minimum memory but |
| is slow and reduces compression ratio; memLevel=9 uses maximum memory |
| for optimal speed. The default value is 8. See zconf.h for total memory |
| usage as a function of windowBits and memLevel. |
| |
| The strategy parameter is used to tune the compression algorithm. Use |
| the value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data |
| produced by a filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman |
| encoding only (no string match). Filtered data consists mostly of small |
| values with a somewhat random distribution. In this case, the |
| compression algorithm is tuned to compress them better. The strategy |
| parameter only affects the compression ratio but not the correctness of |
| the compressed output even if it is not set appropriately. |
| |
| The minCompression parameter specifies the minimum reduction in size |
| required for a compressed block to be output when Z_PACKET_FLUSH is |
| used (see the description of deflate above). |
| |
| If next_in is not null, the library will use this buffer to hold also |
| some history information; the buffer must either hold the entire input |
| data, or have at least 1<<(windowBits+1) bytes and be writable. If next_in |
| is null, the library will allocate its own history buffer (and leave next_in |
| null). next_out need not be provided here but must be provided by the |
| application for the next call of deflate(). |
| |
| If the history buffer is provided by the application, next_in must |
| must never be changed by the application since the compressor maintains |
| information inside this buffer from call to call; the application |
| must provide more input only by increasing avail_in. next_in is always |
| reset by the library in this case. |
| |
| deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was |
| not enough memory, Z_STREAM_ERROR if a parameter is invalid (such as |
| an invalid method). msg is set to null if there is no error message. |
| deflateInit2 does not perform any compression: this will be done by |
| deflate(). |
| */ |
| |
| extern int deflateCopy OF((z_stream *dest, |
| z_stream *source)); |
| /* |
| Sets the destination stream as a complete copy of the source stream. If |
| the source stream is using an application-supplied history buffer, a new |
| buffer is allocated for the destination stream. The compressed output |
| buffer is always application-supplied. It's the responsibility of the |
| application to provide the correct values of next_out and avail_out for the |
| next call of deflate. |
| |
| This function is useful when several compression strategies will be |
| tried, for example when there are several ways of pre-processing the input |
| data with a filter. The streams that will be discarded should then be freed |
| by calling deflateEnd. Note that deflateCopy duplicates the internal |
| compression state which can be quite large, so this strategy is slow and |
| can consume lots of memory. |
| |
| deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not |
| enough memory, Z_STREAM_ERROR if the source stream state was inconsistent |
| (such as zalloc being NULL). msg is left unchanged in both source and |
| destination. |
| */ |
| |
| extern int deflateReset OF((z_stream *strm)); |
| /* |
| This function is equivalent to deflateEnd followed by deflateInit, |
| but does not free and reallocate all the internal compression state. |
| The stream will keep the same compression level and any other attributes |
| that may have been set by deflateInit2. |
| |
| deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source |
| stream state was inconsistent (such as zalloc or state being NULL). |
| */ |
| |
| extern int inflateInit2 OF((z_stream *strm, |
| int windowBits)); |
| /* |
| This is another version of inflateInit with more compression options. The |
| fields next_out, zalloc and zfree must be initialized before by the caller. |
| |
| The windowBits parameter is the base two logarithm of the maximum window |
| size (the size of the history buffer). It should be in the range 8..15 for |
| this version of the library (the value 16 will be allowed soon). The |
| default value is 15 if inflateInit is used instead. If a compressed stream |
| with a larger window size is given as input, inflate() will return with |
| the error code Z_DATA_ERROR instead of trying to allocate a larger window. |
| |
| If next_out is not null, the library will use this buffer for the history |
| buffer; the buffer must either be large enough to hold the entire output |
| data, or have at least 1<<windowBits bytes. If next_out is null, the |
| library will allocate its own buffer (and leave next_out null). next_in |
| need not be provided here but must be provided by the application for the |
| next call of inflate(). |
| |
| If the history buffer is provided by the application, next_out must |
| never be changed by the application since the decompressor maintains |
| history information inside this buffer from call to call; the application |
| can only reset next_out to the beginning of the history buffer when |
| avail_out is zero and all output has been consumed. |
| |
| inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was |
| not enough memory, Z_STREAM_ERROR if a parameter is invalid (such as |
| windowBits < 8). msg is set to null if there is no error message. |
| inflateInit2 does not perform any decompression: this will be done by |
| inflate(). |
| */ |
| |
| extern int inflateSync OF((z_stream *strm)); |
| /* |
| Skips invalid compressed data until the special marker (see deflate() |
| above) can be found, or until all available input is skipped. No output |
| is provided. |
| |
| inflateSync returns Z_OK if the special marker has been found, Z_BUF_ERROR |
| if no more input was provided, Z_DATA_ERROR if no marker has been found, |
| or Z_STREAM_ERROR if the stream structure was inconsistent. In the success |
| case, the application may save the current current value of total_in which |
| indicates where valid compressed data was found. In the error case, the |
| application may repeatedly call inflateSync, providing more input each time, |
| until success or end of the input data. |
| */ |
| |
| extern int inflateReset OF((z_stream *strm)); |
| /* |
| This function is equivalent to inflateEnd followed by inflateInit, |
| but does not free and reallocate all the internal decompression state. |
| The stream will keep attributes that may have been set by inflateInit2. |
| |
| inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source |
| stream state was inconsistent (such as zalloc or state being NULL). |
| */ |
| |
| extern int inflateIncomp OF((z_stream *strm)); |
| /* |
| This function adds the data at next_in (avail_in bytes) to the output |
| history without performing any output. There must be no pending output, |
| and the decompressor must be expecting to see the start of a block. |
| Calling this function is equivalent to decompressing a stored block |
| containing the data at next_in (except that the data is not output). |
| */ |
| |
| /* checksum functions */ |
| |
| /* |
| This function is not related to compression but is exported |
| anyway because it might be useful in applications using the |
| compression library. |
| */ |
| |
| extern uLong adler32 OF((uLong adler, Bytef *buf, uInt len)); |
| |
| /* |
| Update a running Adler-32 checksum with the bytes buf[0..len-1] and |
| return the updated checksum. If buf is NULL, this function returns |
| the required initial value for the checksum. |
| An Adler-32 checksum is almost as reliable as a CRC32 but can be computed |
| much faster. Usage example: |
| |
| uLong adler = adler32(0L, Z_NULL, 0); |
| |
| while (read_buffer(buffer, length) != EOF) { |
| adler = adler32(adler, buffer, length); |
| } |
| if (adler != original_adler) error(); |
| */ |
| |
| #ifndef _Z_UTIL_H |
| struct internal_state {int dummy;}; /* hack for buggy compilers */ |
| #endif |
| |
| #endif /* _ZLIB_H */ |