blob: f5275c7c4cdef5379c74bce103af5d3ddf7b8c04 [file] [log] [blame]
/*************************************************
* Perl-Compatible Regular Expressions *
*************************************************/
/* PCRE is a library of functions to support regular expressions whose syntax
and semantics are as close as possible to those of the Perl 5 language.
Written by Philip Hazel
Original API code Copyright (c) 1997-2012 University of Cambridge
New API code Copyright (c) 2016 University of Cambridge
-----------------------------------------------------------------------------
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
* Neither the name of the University of Cambridge nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
-----------------------------------------------------------------------------
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#define NLBLOCK mb /* Block containing newline information */
#define PSSTART start_subject /* Field containing processed string start */
#define PSEND end_subject /* Field containing processed string end */
#include "pcre2_internal.h"
/* Masks for identifying the public options that are permitted at match time.
*/
#define PUBLIC_MATCH_OPTIONS \
(PCRE2_ANCHORED|PCRE2_NOTBOL|PCRE2_NOTEOL|PCRE2_NOTEMPTY| \
PCRE2_NOTEMPTY_ATSTART|PCRE2_NO_UTF_CHECK|PCRE2_PARTIAL_HARD| \
PCRE2_PARTIAL_SOFT)
#define PUBLIC_JIT_MATCH_OPTIONS \
(PCRE2_NO_UTF_CHECK|PCRE2_NOTBOL|PCRE2_NOTEOL|PCRE2_NOTEMPTY|\
PCRE2_NOTEMPTY_ATSTART|PCRE2_PARTIAL_SOFT|PCRE2_PARTIAL_HARD)
/* The mb->capture_last field uses the lower 16 bits for the last captured
substring (which can never be greater than 65535) and a bit in the top half
to mean "capture vector overflowed". This odd way of doing things was
implemented when it was realized that preserving and restoring the overflow bit
whenever the last capture number was saved/restored made for a neater
interface, and doing it this way saved on (a) another variable, which would
have increased the stack frame size (a big NO-NO in PCRE) and (b) another
separate set of save/restore instructions. The following defines are used in
implementing this. */
#define CAPLMASK 0x0000ffff /* The bits used for last_capture */
#define OVFLMASK 0xffff0000 /* The bits used for the overflow flag */
#define OVFLBIT 0x00010000 /* The bit that is set for overflow */
/* Bits for setting in mb->match_function_type to indicate two special types
of call to match(). We do it this way to save on using another stack variable,
as stack usage is to be discouraged. */
#define MATCH_CONDASSERT 1 /* Called to check a condition assertion */
#define MATCH_CBEGROUP 2 /* Could-be-empty unlimited repeat group */
/* Non-error returns from the match() function. Error returns are externally
defined PCRE2_ERROR_xxx codes, which are all negative. */
#define MATCH_MATCH 1
#define MATCH_NOMATCH 0
/* Special internal returns from the match() function. Make them sufficiently
negative to avoid the external error codes. */
#define MATCH_ACCEPT (-999)
#define MATCH_KETRPOS (-998)
#define MATCH_ONCE (-997)
/* The next 5 must be kept together and in sequence so that a test that checks
for any one of them can use a range. */
#define MATCH_COMMIT (-996)
#define MATCH_PRUNE (-995)
#define MATCH_SKIP (-994)
#define MATCH_SKIP_ARG (-993)
#define MATCH_THEN (-992)
#define MATCH_BACKTRACK_MAX MATCH_THEN
#define MATCH_BACKTRACK_MIN MATCH_COMMIT
/* Min and max values for the common repeats; for the maxima, 0 => infinity */
static const char rep_min[] = { 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, };
static const char rep_max[] = { 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, };
/* Maximum number of ovector elements that can be saved on the system stack
when processing OP_RECURSE in non-HEAP_MATCH_RECURSE mode. If the ovector is
bigger, malloc() is used. This value should be a multiple of 3, because the
ovector length is always a multiple of 3. */
#define OP_RECURSE_STACK_SAVE_MAX 45
/*************************************************
* Match a back-reference *
*************************************************/
/* This function is called only when it is known that the offset lies within
the offsets that have so far been used in the match. Note that in caseless
UTF-8 mode, the number of subject bytes matched may be different to the number
of reference bytes. (In theory this could also happen in UTF-16 mode, but it
seems unlikely.)
Arguments:
offset index into the offset vector
offset_top top of the used offset vector
eptr pointer into the subject
mb points to match block
caseless TRUE if caseless
lengthptr pointer for returning the length matched
Returns: = 0 sucessful match; number of code units matched is set
< 0 no match
> 0 partial match
*/
static int
match_ref(PCRE2_SIZE offset, PCRE2_SIZE offset_top, register PCRE2_SPTR eptr,
match_block *mb, BOOL caseless, PCRE2_SIZE *lengthptr)
{
#if defined SUPPORT_UNICODE
BOOL utf = (mb->poptions & PCRE2_UTF) != 0;
#endif
register PCRE2_SPTR p;
PCRE2_SIZE length;
PCRE2_SPTR eptr_start = eptr;
/* Deal with an unset group. The default is no match, but there is an option to
match an empty string. */
if (offset >= offset_top || mb->ovector[offset] == PCRE2_UNSET)
{
if ((mb->poptions & PCRE2_MATCH_UNSET_BACKREF) != 0)
{
*lengthptr = 0;
return 0; /* Match */
}
else return -1; /* No match */
}
/* Separate the caseless and UTF cases for speed. */
p = mb->start_subject + mb->ovector[offset];
length = mb->ovector[offset+1] - mb->ovector[offset];
if (caseless)
{
#if defined SUPPORT_UNICODE
if (utf)
{
/* Match characters up to the end of the reference. NOTE: the number of
code units matched may differ, because in UTF-8 there are some characters
whose upper and lower case versions code have different numbers of bytes.
For example, U+023A (2 bytes in UTF-8) is the upper case version of U+2C65
(3 bytes in UTF-8); a sequence of 3 of the former uses 6 bytes, as does a
sequence of two of the latter. It is important, therefore, to check the
length along the reference, not along the subject (earlier code did this
wrong). */
PCRE2_SPTR endptr = p + length;
while (p < endptr)
{
uint32_t c, d;
const ucd_record *ur;
if (eptr >= mb->end_subject) return 1; /* Partial match */
GETCHARINC(c, eptr);
GETCHARINC(d, p);
ur = GET_UCD(d);
if (c != d && c != (uint32_t)((int)d + ur->other_case))
{
const uint32_t *pp = PRIV(ucd_caseless_sets) + ur->caseset;
for (;;)
{
if (c < *pp) return -1; /* No match */
if (c == *pp++) break;
}
}
}
}
else
#endif
/* Not in UTF mode */
{
for (; length > 0; length--)
{
uint32_t cc, cp;
if (eptr >= mb->end_subject) return 1; /* Partial match */
cc = UCHAR21TEST(eptr);
cp = UCHAR21TEST(p);
if (TABLE_GET(cp, mb->lcc, cp) != TABLE_GET(cc, mb->lcc, cc))
return -1; /* No match */
p++;
eptr++;
}
}
}
/* In the caseful case, we can just compare the code units, whether or not we
are in UTF mode. */
else
{
for (; length > 0; length--)
{
if (eptr >= mb->end_subject) return 1; /* Partial match */
if (UCHAR21INCTEST(p) != UCHAR21INCTEST(eptr)) return -1; /*No match */
}
}
*lengthptr = eptr - eptr_start;
return 0; /* Match */
}
/***************************************************************************
****************************************************************************
RECURSION IN THE match() FUNCTION
The match() function is highly recursive, though not every recursive call
increases the recursion depth. Nevertheless, some regular expressions can cause
it to recurse to a great depth. I was writing for Unix, so I just let it call
itself recursively. This uses the stack for saving everything that has to be
saved for a recursive call. On Unix, the stack can be large, and this works
fine.
It turns out that on some non-Unix-like systems there are problems with
programs that use a lot of stack. (This despite the fact that every last chip
has oodles of memory these days, and techniques for extending the stack have
been known for decades.) So....
There is a fudge, triggered by defining HEAP_MATCH_RECURSE, which avoids
recursive calls by keeping local variables that need to be preserved in blocks
of memory on the heap instead instead of on the stack. Macros are used to
achieve this so that the actual code doesn't look very different to what it
always used to.
The original heap-recursive code used longjmp(). However, it seems that this
can be very slow on some operating systems. Following a suggestion from Stan
Switzer, the use of longjmp() has been abolished, at the cost of having to
provide a unique number for each call to RMATCH. There is no way of generating
a sequence of numbers at compile time in C. I have given them names, to make
them stand out more clearly.
Crude tests on x86 Linux show a small speedup of around 5-8%. However, on
FreeBSD, avoiding longjmp() more than halves the time taken to run the standard
tests. Furthermore, not using longjmp() means that local dynamic variables
don't have indeterminate values; this has meant that the frame size can be
reduced because the result can be "passed back" by straight setting of the
variable instead of being passed in the frame.
****************************************************************************
***************************************************************************/
/* Numbers for RMATCH calls. When this list is changed, the code at HEAP_RETURN
below must be updated in sync. */
enum { RM1=1, RM2, RM3, RM4, RM5, RM6, RM7, RM8, RM9, RM10,
RM11, RM12, RM13, RM14, RM15, RM16, RM17, RM18, RM19, RM20,
RM21, RM22, RM23, RM24, RM25, RM26, RM27, RM28, RM29, RM30,
RM31, RM32, RM33, RM34, RM35, RM36, RM37, RM38, RM39, RM40,
RM41, RM42, RM43, RM44, RM45, RM46, RM47, RM48, RM49, RM50,
RM51, RM52, RM53, RM54, RM55, RM56, RM57, RM58, RM59, RM60,
RM61, RM62, RM63, RM64, RM65, RM66, RM67, RM68 };
/* These versions of the macros use the stack, as normal. Note that the "rw"
argument of RMATCH isn't actually used in this definition. */
#ifndef HEAP_MATCH_RECURSE
#define REGISTER register
#define RMATCH(ra,rb,rc,rd,re,rw) \
rrc = match(ra,rb,mstart,rc,rd,re,rdepth+1)
#define RRETURN(ra) return ra
#else
/* These versions of the macros manage a private stack on the heap. Note that
the "rd" argument of RMATCH isn't actually used in this definition. It's the mb
argument of match(), which never changes. */
#define REGISTER
#define RMATCH(ra,rb,rc,rd,re,rw)\
{\
heapframe *newframe = frame->Xnextframe;\
if (newframe == NULL)\
{\
newframe = (heapframe *)(mb->stack_memctl.malloc)\
(sizeof(heapframe), mb->stack_memctl.memory_data);\
if (newframe == NULL) RRETURN(PCRE2_ERROR_NOMEMORY);\
newframe->Xnextframe = NULL;\
frame->Xnextframe = newframe;\
}\
frame->Xwhere = rw;\
newframe->Xeptr = ra;\
newframe->Xecode = rb;\
newframe->Xmstart = mstart;\
newframe->Xoffset_top = rc;\
newframe->Xeptrb = re;\
newframe->Xrdepth = frame->Xrdepth + 1;\
newframe->Xprevframe = frame;\
frame = newframe;\
goto HEAP_RECURSE;\
L_##rw:;\
}
#define RRETURN(ra)\
{\
heapframe *oldframe = frame;\
frame = oldframe->Xprevframe;\
if (frame != NULL)\
{\
rrc = ra;\
goto HEAP_RETURN;\
}\
return ra;\
}
/* Structure for remembering the local variables in a private frame. Arrange it
so as to minimize the number of holes. */
typedef struct heapframe {
struct heapframe *Xprevframe;
struct heapframe *Xnextframe;
#ifdef SUPPORT_UNICODE
PCRE2_SPTR Xcharptr;
#endif
PCRE2_SPTR Xeptr;
PCRE2_SPTR Xecode;
PCRE2_SPTR Xmstart;
PCRE2_SPTR Xcallpat;
PCRE2_SPTR Xdata;
PCRE2_SPTR Xnext_ecode;
PCRE2_SPTR Xpp;
PCRE2_SPTR Xprev;
PCRE2_SPTR Xsaved_eptr;
eptrblock *Xeptrb;
PCRE2_SIZE Xlength;
PCRE2_SIZE Xoffset;
PCRE2_SIZE Xoffset_top;
PCRE2_SIZE Xsave_offset1, Xsave_offset2, Xsave_offset3;
uint32_t Xfc;
uint32_t Xnumber;
uint32_t Xrdepth;
uint32_t Xop;
uint32_t Xsave_capture_last;
#ifdef SUPPORT_UNICODE
uint32_t Xprop_value;
int Xprop_type;
int Xprop_fail_result;
int Xoclength;
#endif
int Xcodelink;
int Xctype;
int Xfi;
int Xmax;
int Xmin;
int Xwhere; /* Where to jump back to */
BOOL Xcondition;
BOOL Xcur_is_word;
BOOL Xprev_is_word;
eptrblock Xnewptrb;
recursion_info Xnew_recursive;
#ifdef SUPPORT_UNICODE
PCRE2_UCHAR Xocchars[6];
#endif
} heapframe;
#endif
/***************************************************************************
***************************************************************************/
/* When HEAP_MATCH_RECURSE is not defined, the match() function implements
backtrack points by calling itself recursively in all but one case. The one
special case is when processing OP_RECURSE, which specifies recursion in the
pattern. The entire ovector must be saved and restored while processing
OP_RECURSE. If the ovector is small enough, instead of calling match()
directly, op_recurse_ovecsave() is called. This function uses the system stack
to save the ovector while calling match() to process the pattern recursion. */
#ifndef HEAP_MATCH_RECURSE
/* We need a prototype for match() because it is mutually recursive with
op_recurse_ovecsave(). */
static int
match(REGISTER PCRE2_SPTR eptr, REGISTER PCRE2_SPTR ecode, PCRE2_SPTR mstart,
PCRE2_SIZE offset_top, match_block *mb, eptrblock *eptrb, uint32_t rdepth);
/*************************************************
* Process OP_RECURSE, stacking ovector *
*************************************************/
/* When this function is called, mb->recursive has already been updated to
point to a new recursion data block, and all its fields other than ovec_save
have been set.
This function exists so that the local vector variable ovecsave is no longer
defined in the match() function, as it was in PCRE1. It is used only when there
is recursion in the pattern, so it wastes a lot of stack to have it defined for
every call of match(). We now use this function as an indirect way of calling
match() only in the case when ovecsave is needed. (David Wheeler used to say
"All problems in computer science can be solved by another level of
indirection.")
HOWEVER: when this file is compiled by gcc in an optimizing mode, because this
function is called only once, and only from within match(), gcc will "inline"
it - that is, move it inside match() - and this completely negates its reason
for existence. Therefore, we mark it as non-inline when gcc is in use.
Arguments:
eptr pointer to current character in subject
callpat the recursion point in the pattern
mstart pointer to the current match start position (can be modified
by encountering \K)
offset_top current top pointer (highest ovector offset used + 1)
mb pointer to "static" info block for the match
eptrb pointer to chain of blocks containing eptr at start of
brackets - for testing for empty matches
rdepth the recursion depth
Returns: a match() return code
*/
static int
#ifdef __GNUC__
__attribute__ ((noinline))
#endif
op_recurse_ovecsave(REGISTER PCRE2_SPTR eptr, PCRE2_SPTR callpat,
PCRE2_SPTR mstart, PCRE2_SIZE offset_top, match_block *mb, eptrblock *eptrb,
uint32_t rdepth)
{
register int rrc;
BOOL cbegroup = *callpat >= OP_SBRA;
recursion_info *new_recursive = mb->recursive;
PCRE2_SIZE ovecsave[OP_RECURSE_STACK_SAVE_MAX];
/* Save the ovector */
new_recursive->ovec_save = ovecsave;
memcpy(ovecsave, mb->ovector, mb->offset_end * sizeof(PCRE2_SIZE));
/* Do the recursion. After processing each alternative, restore the ovector
data and the last captured value. */
do
{
if (cbegroup) mb->match_function_type |= MATCH_CBEGROUP;
rrc = match(eptr, callpat + PRIV(OP_lengths)[*callpat], mstart, offset_top,
mb, eptrb, rdepth + 1);
memcpy(mb->ovector, new_recursive->ovec_save,
mb->offset_end * sizeof(PCRE2_SIZE));
mb->capture_last = new_recursive->saved_capture_last;
if (rrc == MATCH_MATCH || rrc == MATCH_ACCEPT) return rrc;
/* PCRE does not allow THEN, SKIP, PRUNE or COMMIT to escape beyond a
recursion; they cause a NOMATCH for the entire recursion. These codes
are defined in a range that can be tested for. */
if (rrc >= MATCH_BACKTRACK_MIN && rrc <= MATCH_BACKTRACK_MAX)
return MATCH_NOMATCH;
/* Any return code other than NOMATCH is an error. Otherwise, advance to the
next alternative or to the end of the recursing subpattern. If there were
nested recursions, mb->recursive might be changed, so reset it before
looping. */
if (rrc != MATCH_NOMATCH) return rrc;
mb->recursive = new_recursive;
callpat += GET(callpat, 1);
}
while (*callpat == OP_ALT); /* Loop for the alternatives */
/* None of the alternatives matched. */
return MATCH_NOMATCH;
}
#endif /* HEAP_MATCH_RECURSE */
/*************************************************
* Match from current position *
*************************************************/
/* This function is called recursively in many circumstances. Whenever it
returns a negative (error) response, the outer incarnation must also return the
same response. */
/* These macros pack up tests that are used for partial matching, and which
appear several times in the code. We set the "hit end" flag if the pointer is
at the end of the subject and also past the earliest inspected character (i.e.
something has been matched, even if not part of the actual matched string). For
hard partial matching, we then return immediately. The second one is used when
we already know we are past the end of the subject. */
#define CHECK_PARTIAL()\
if (mb->partial != 0 && eptr >= mb->end_subject && \
eptr > mb->start_used_ptr) \
{ \
mb->hitend = TRUE; \
if (mb->partial > 1) RRETURN(PCRE2_ERROR_PARTIAL); \
}
#define SCHECK_PARTIAL()\
if (mb->partial != 0 && eptr > mb->start_used_ptr) \
{ \
mb->hitend = TRUE; \
if (mb->partial > 1) RRETURN(PCRE2_ERROR_PARTIAL); \
}
/* Performance note: It might be tempting to extract commonly used fields from
the mb structure (e.g. utf, end_subject) into individual variables to improve
performance. Tests using gcc on a SPARC disproved this; in the first case, it
made performance worse.
Arguments:
eptr pointer to current character in subject
ecode pointer to current position in compiled code
mstart pointer to the current match start position (can be modified
by encountering \K)
offset_top current top pointer (highest ovector offset used + 1)
mb pointer to "static" info block for the match
eptrb pointer to chain of blocks containing eptr at start of
brackets - for testing for empty matches
rdepth the recursion depth
Returns: MATCH_MATCH if matched ) these values are >= 0
MATCH_NOMATCH if failed to match )
a negative MATCH_xxx value for PRUNE, SKIP, etc
a negative PCRE2_ERROR_xxx value if aborted by an error condition
(e.g. stopped by repeated call or recursion limit)
*/
static int
match(REGISTER PCRE2_SPTR eptr, REGISTER PCRE2_SPTR ecode, PCRE2_SPTR mstart,
PCRE2_SIZE offset_top, match_block *mb, eptrblock *eptrb, uint32_t rdepth)
{
/* These variables do not need to be preserved over recursion in this function,
so they can be ordinary variables in all cases. Mark some of them with
"register" because they are used a lot in loops. */
register int rrc; /* Returns from recursive calls */
register int i; /* Used for loops not involving calls to RMATCH() */
register uint32_t c; /* Character values not kept over RMATCH() calls */
register BOOL utf; /* Local copy of UTF flag for speed */
BOOL minimize, possessive; /* Quantifier options */
BOOL caseless;
int condcode;
/* When recursion is not being used, all "local" variables that have to be
preserved over calls to RMATCH() are part of a "frame". We set up the top-level
frame on the stack here; subsequent instantiations are obtained from the heap
whenever RMATCH() does a "recursion". See the macro definitions above. Putting
the top-level on the stack rather than malloc-ing them all gives a performance
boost in many cases where there is not much "recursion". */
#ifdef HEAP_MATCH_RECURSE
heapframe *frame = (heapframe *)mb->match_frames_base;
/* Copy in the original argument variables */
frame->Xeptr = eptr;
frame->Xecode = ecode;
frame->Xmstart = mstart;
frame->Xoffset_top = offset_top;
frame->Xeptrb = eptrb;
frame->Xrdepth = rdepth;
/* This is where control jumps back to to effect "recursion" */
HEAP_RECURSE:
/* Macros make the argument variables come from the current frame */
#define eptr frame->Xeptr
#define ecode frame->Xecode
#define mstart frame->Xmstart
#define offset_top frame->Xoffset_top
#define eptrb frame->Xeptrb
#define rdepth frame->Xrdepth
/* Ditto for the local variables */
#ifdef SUPPORT_UNICODE
#define charptr frame->Xcharptr
#define prop_value frame->Xprop_value
#define prop_type frame->Xprop_type
#define prop_fail_result frame->Xprop_fail_result
#define oclength frame->Xoclength
#define occhars frame->Xocchars
#endif
#define callpat frame->Xcallpat
#define codelink frame->Xcodelink
#define data frame->Xdata
#define next_ecode frame->Xnext_ecode
#define pp frame->Xpp
#define prev frame->Xprev
#define saved_eptr frame->Xsaved_eptr
#define new_recursive frame->Xnew_recursive
#define ctype frame->Xctype
#define fc frame->Xfc
#define fi frame->Xfi
#define length frame->Xlength
#define max frame->Xmax
#define min frame->Xmin
#define number frame->Xnumber
#define offset frame->Xoffset
#define op frame->Xop
#define save_capture_last frame->Xsave_capture_last
#define save_offset1 frame->Xsave_offset1
#define save_offset2 frame->Xsave_offset2
#define save_offset3 frame->Xsave_offset3
#define condition frame->Xcondition
#define cur_is_word frame->Xcur_is_word
#define prev_is_word frame->Xprev_is_word
#define newptrb frame->Xnewptrb
/* When normal stack-based recursion is being used for match(), local variables
are allocated on the stack and get preserved during recursion in the usual way.
In this environment, fi and i, and fc and c, can be the same variables. */
#else /* HEAP_MATCH_RECURSE not defined */
#define fi i
#define fc c
/* Many of the following variables are used only in small blocks of the code.
My normal style of coding would have declared them within each of those blocks.
However, in order to accommodate the version of this code that uses an external
"stack" implemented on the heap, it is easier to declare them all here, so the
declarations can be cut out in a block. The only declarations within blocks
below are for variables that do not have to be preserved over a recursive call
to RMATCH(). */
#ifdef SUPPORT_UNICODE
PCRE2_SPTR charptr;
#endif
PCRE2_SPTR callpat;
PCRE2_SPTR data;
PCRE2_SPTR next_ecode;
PCRE2_SPTR pp;
PCRE2_SPTR prev;
PCRE2_SPTR saved_eptr;
PCRE2_SIZE length;
PCRE2_SIZE offset;
PCRE2_SIZE save_offset1, save_offset2, save_offset3;
uint32_t number;
uint32_t op;
uint32_t save_capture_last;
#ifdef SUPPORT_UNICODE
uint32_t prop_value;
int prop_type;
int prop_fail_result;
int oclength;
PCRE2_UCHAR occhars[6];
#endif
int codelink;
int ctype;
int max;
int min;
BOOL condition;
BOOL cur_is_word;
BOOL prev_is_word;
eptrblock newptrb;
recursion_info new_recursive;
#endif /* HEAP_MATCH_RECURSE not defined */
/* To save space on the stack and in the heap frame, I have doubled up on some
of the local variables that are used only in localised parts of the code, but
still need to be preserved over recursive calls of match(). These macros define
the alternative names that are used. */
#define allow_zero cur_is_word
#define cbegroup condition
#define code_offset codelink
#define condassert condition
#define foc number
#define matched_once prev_is_word
#define save_mark data
/* These statements are here to stop the compiler complaining about unitialized
variables. */
#ifdef SUPPORT_UNICODE
prop_value = 0;
prop_fail_result = 0;
#endif
/* This label is used for tail recursion, which is used in a few cases even
when HEAP_MATCH_RECURSE is not defined, in order to reduce the amount of stack
that is used. Thanks to Ian Taylor for noticing this possibility and sending
the original patch. */
TAIL_RECURSE:
/* OK, now we can get on with the real code of the function. Recursive calls
are specified by the macro RMATCH and RRETURN is used to return. When
HEAP_MATCH_RECURSE is *not* defined, these just turn into a recursive call to
match() and a "return", respectively. However, RMATCH isn't like a function
call because it's quite a complicated macro. It has to be used in one
particular way. This shouldn't, however, impact performance when true recursion
is being used. */
#ifdef SUPPORT_UNICODE
utf = (mb->poptions & PCRE2_UTF) != 0;
#else
utf = FALSE;
#endif
/* First check that we haven't called match() too many times, or that we
haven't exceeded the recursive call limit. */
if (mb->match_call_count++ >= mb->match_limit) RRETURN(PCRE2_ERROR_MATCHLIMIT);
if (rdepth >= mb->match_limit_recursion) RRETURN(PCRE2_ERROR_RECURSIONLIMIT);
/* At the start of a group with an unlimited repeat that may match an empty
string, the variable mb->match_function_type contains the MATCH_CBEGROUP bit.
It is done this way to save having to use another function argument, which
would take up space on the stack. See also MATCH_CONDASSERT below.
When MATCH_CBEGROUP is set, add the current subject pointer to the chain of
such remembered pointers, to be checked when we hit the closing ket, in order
to break infinite loops that match no characters. When match() is called in
other circumstances, don't add to the chain. The MATCH_CBEGROUP feature must
NOT be used with tail recursion, because the memory block that is used is on
the stack, so a new one may be required for each match(). */
if ((mb->match_function_type & MATCH_CBEGROUP) != 0)
{
newptrb.epb_saved_eptr = eptr;
newptrb.epb_prev = eptrb;
eptrb = &newptrb;
mb->match_function_type &= ~MATCH_CBEGROUP;
}
/* Now, at last, we can start processing the opcodes. */
for (;;)
{
minimize = possessive = FALSE;
op = *ecode;
switch(op)
{
case OP_MARK:
mb->nomatch_mark = ecode + 2;
mb->mark = NULL; /* In case previously set by assertion */
RMATCH(eptr, ecode + PRIV(OP_lengths)[*ecode] + ecode[1], offset_top, mb,
eptrb, RM55);
if ((rrc == MATCH_MATCH || rrc == MATCH_ACCEPT) &&
mb->mark == NULL) mb->mark = ecode + 2;
/* A return of MATCH_SKIP_ARG means that matching failed at SKIP with an
argument, and we must check whether that argument matches this MARK's
argument. It is passed back in mb->start_match_ptr (an overloading of that
variable). If it does match, we reset that variable to the current subject
position and return MATCH_SKIP. Otherwise, pass back the return code
unaltered. */
else if (rrc == MATCH_SKIP_ARG &&
PRIV(strcmp)(ecode + 2, mb->start_match_ptr) == 0)
{
mb->start_match_ptr = eptr;
RRETURN(MATCH_SKIP);
}
RRETURN(rrc);
case OP_FAIL:
RRETURN(MATCH_NOMATCH);
case OP_COMMIT:
RMATCH(eptr, ecode + PRIV(OP_lengths)[*ecode], offset_top, mb,
eptrb, RM52);
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
RRETURN(MATCH_COMMIT);
case OP_PRUNE:
RMATCH(eptr, ecode + PRIV(OP_lengths)[*ecode], offset_top, mb,
eptrb, RM51);
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
RRETURN(MATCH_PRUNE);
case OP_PRUNE_ARG:
mb->nomatch_mark = ecode + 2;
mb->mark = NULL; /* In case previously set by assertion */
RMATCH(eptr, ecode + PRIV(OP_lengths)[*ecode] + ecode[1], offset_top, mb,
eptrb, RM56);
if ((rrc == MATCH_MATCH || rrc == MATCH_ACCEPT) &&
mb->mark == NULL) mb->mark = ecode + 2;
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
RRETURN(MATCH_PRUNE);
case OP_SKIP:
RMATCH(eptr, ecode + PRIV(OP_lengths)[*ecode], offset_top, mb,
eptrb, RM53);
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
mb->start_match_ptr = eptr; /* Pass back current position */
RRETURN(MATCH_SKIP);
/* Note that, for Perl compatibility, SKIP with an argument does NOT set
nomatch_mark. When a pattern match ends with a SKIP_ARG for which there was
not a matching mark, we have to re-run the match, ignoring the SKIP_ARG
that failed and any that precede it (either they also failed, or were not
triggered). To do this, we maintain a count of executed SKIP_ARGs. If a
SKIP_ARG gets to top level, the match is re-run with mb->ignore_skip_arg
set to the count of the one that failed. */
case OP_SKIP_ARG:
mb->skip_arg_count++;
if (mb->skip_arg_count <= mb->ignore_skip_arg)
{
ecode += PRIV(OP_lengths)[*ecode] + ecode[1];
break;
}
RMATCH(eptr, ecode + PRIV(OP_lengths)[*ecode] + ecode[1], offset_top, mb,
eptrb, RM57);
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
/* Pass back the current skip name by overloading mb->start_match_ptr and
returning the special MATCH_SKIP_ARG return code. This will either be
caught by a matching MARK, or get to the top, where it causes a rematch
with mb->ignore_skip_arg set to the value of mb->skip_arg_count. */
mb->start_match_ptr = ecode + 2;
RRETURN(MATCH_SKIP_ARG);
/* For THEN (and THEN_ARG) we pass back the address of the opcode, so that
the branch in which it occurs can be determined. Overload the start of
match pointer to do this. */
case OP_THEN:
RMATCH(eptr, ecode + PRIV(OP_lengths)[*ecode], offset_top, mb,
eptrb, RM54);
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
mb->start_match_ptr = ecode;
RRETURN(MATCH_THEN);
case OP_THEN_ARG:
mb->nomatch_mark = ecode + 2;
mb->mark = NULL; /* In case previously set by assertion */
RMATCH(eptr, ecode + PRIV(OP_lengths)[*ecode] + ecode[1], offset_top,
mb, eptrb, RM58);
if ((rrc == MATCH_MATCH || rrc == MATCH_ACCEPT) &&
mb->mark == NULL) mb->mark = ecode + 2;
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
mb->start_match_ptr = ecode;
RRETURN(MATCH_THEN);
/* Handle an atomic group that does not contain any capturing parentheses.
This can be handled like an assertion. Prior to 8.13, all atomic groups
were handled this way. In 8.13, the code was changed as below for ONCE, so
that backups pass through the group and thereby reset captured values.
However, this uses a lot more stack, so in 8.20, atomic groups that do not
contain any captures generate OP_ONCE_NC, which can be handled in the old,
less stack intensive way.
Check the alternative branches in turn - the matching won't pass the KET
for this kind of subpattern. If any one branch matches, we carry on as at
the end of a normal bracket, leaving the subject pointer, but resetting
the start-of-match value in case it was changed by \K. */
case OP_ONCE_NC:
prev = ecode;
saved_eptr = eptr;
save_mark = mb->mark;
do
{
RMATCH(eptr, ecode + 1 + LINK_SIZE, offset_top, mb, eptrb, RM64);
if (rrc == MATCH_MATCH) /* Note: _not_ MATCH_ACCEPT */
{
mstart = mb->start_match_ptr;
break;
}
if (rrc == MATCH_THEN)
{
next_ecode = ecode + GET(ecode,1);
if (mb->start_match_ptr < next_ecode &&
(*ecode == OP_ALT || *next_ecode == OP_ALT))
rrc = MATCH_NOMATCH;
}
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
ecode += GET(ecode,1);
mb->mark = save_mark;
}
while (*ecode == OP_ALT);
/* If hit the end of the group (which could be repeated), fail */
if (*ecode != OP_ONCE_NC && *ecode != OP_ALT) RRETURN(MATCH_NOMATCH);
/* Continue as from after the group, updating the offsets high water
mark, since extracts may have been taken. */
do ecode += GET(ecode, 1); while (*ecode == OP_ALT);
offset_top = mb->end_offset_top;
eptr = mb->end_match_ptr;
/* For a non-repeating ket, just continue at this level. This also
happens for a repeating ket if no characters were matched in the group.
This is the forcible breaking of infinite loops as implemented in Perl
5.005. */
if (*ecode == OP_KET || eptr == saved_eptr)
{
ecode += 1+LINK_SIZE;
break;
}
/* The repeating kets try the rest of the pattern or restart from the
preceding bracket, in the appropriate order. The second "call" of match()
uses tail recursion, to avoid using another stack frame. */
if (*ecode == OP_KETRMIN)
{
RMATCH(eptr, ecode + 1 + LINK_SIZE, offset_top, mb, eptrb, RM65);
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
ecode = prev;
goto TAIL_RECURSE;
}
else /* OP_KETRMAX */
{
RMATCH(eptr, prev, offset_top, mb, eptrb, RM66);
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
ecode += 1 + LINK_SIZE;
goto TAIL_RECURSE;
}
/* Control never gets here */
/* Handle a capturing bracket, other than those that are possessive with an
unlimited repeat. If there is space in the offset vector, save the current
subject position in the working slot at the top of the vector. We mustn't
change the current values of the data slot, because they may be set from a
previous iteration of this group, and be referred to by a reference inside
the group. A failure to match might occur after the group has succeeded,
if something later on doesn't match. For this reason, we need to restore
the working value and also the values of the final offsets, in case they
were set by a previous iteration of the same bracket.
If there isn't enough space in the offset vector, treat this as if it were
a non-capturing bracket. Don't worry about setting the flag for the error
case here; that is handled in the code for KET. */
case OP_CBRA:
case OP_SCBRA:
number = GET2(ecode, 1+LINK_SIZE);
offset = number << 1;
if (offset < mb->offset_max)
{
save_offset1 = mb->ovector[offset];
save_offset2 = mb->ovector[offset+1];
save_offset3 = mb->ovector[mb->offset_end - number];
save_capture_last = mb->capture_last;
save_mark = mb->mark;
mb->ovector[mb->offset_end - number] = eptr - mb->start_subject;
for (;;)
{
if (op >= OP_SBRA) mb->match_function_type |= MATCH_CBEGROUP;
RMATCH(eptr, ecode + PRIV(OP_lengths)[*ecode], offset_top, mb,
eptrb, RM1);
if (rrc == MATCH_ONCE) break; /* Backing up through an atomic group */
/* If we backed up to a THEN, check whether it is within the current
branch by comparing the address of the THEN that is passed back with
the end of the branch. If it is within the current branch, and the
branch is one of two or more alternatives (it either starts or ends
with OP_ALT), we have reached the limit of THEN's action, so convert
the return code to NOMATCH, which will cause normal backtracking to
happen from now on. Otherwise, THEN is passed back to an outer
alternative. This implements Perl's treatment of parenthesized groups,
where a group not containing | does not affect the current alternative,
that is, (X) is NOT the same as (X|(*F)). */
if (rrc == MATCH_THEN)
{
next_ecode = ecode + GET(ecode,1);
if (mb->start_match_ptr < next_ecode &&
(*ecode == OP_ALT || *next_ecode == OP_ALT))
rrc = MATCH_NOMATCH;
}
/* Anything other than NOMATCH is passed back. */
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
mb->capture_last = save_capture_last;
ecode += GET(ecode, 1);
mb->mark = save_mark;
if (*ecode != OP_ALT) break;
}
mb->ovector[offset] = save_offset1;
mb->ovector[offset+1] = save_offset2;
mb->ovector[mb->offset_end - number] = save_offset3;
/* At this point, rrc will be one of MATCH_ONCE or MATCH_NOMATCH. */
RRETURN(rrc);
}
/* FALL THROUGH ... Insufficient room for saving captured contents. Treat
as a non-capturing bracket. */
/* VVVVVVVVVVVVVVVVVVVVVVVVV */
/* VVVVVVVVVVVVVVVVVVVVVVVVV */
/* Non-capturing or atomic group, except for possessive with unlimited
repeat and ONCE group with no captures. Loop for all the alternatives.
When we get to the final alternative within the brackets, we used to return
the result of a recursive call to match() whatever happened so it was
possible to reduce stack usage by turning this into a tail recursion,
except in the case of a possibly empty group. However, now that there is
the possiblity of (*THEN) occurring in the final alternative, this
optimization is no longer always possible.
We can optimize if we know there are no (*THEN)s in the pattern; at present
this is the best that can be done.
MATCH_ONCE is returned when the end of an atomic group is successfully
reached, but subsequent matching fails. It passes back up the tree (causing
captured values to be reset) until the original atomic group level is
reached. This is tested by comparing mb->once_target with the start of the
group. At this point, the return is converted into MATCH_NOMATCH so that
previous backup points can be taken. */
case OP_ONCE:
case OP_BRA:
case OP_SBRA:
for (;;)
{
if (op >= OP_SBRA || op == OP_ONCE)
mb->match_function_type |= MATCH_CBEGROUP;
/* If this is not a possibly empty group, and there are no (*THEN)s in
the pattern, and this is the final alternative, optimize as described
above. */
else if (!mb->hasthen && ecode[GET(ecode, 1)] != OP_ALT)
{
ecode += PRIV(OP_lengths)[*ecode];
goto TAIL_RECURSE;
}
/* In all other cases, we have to make another call to match(). */
save_mark = mb->mark;
save_capture_last = mb->capture_last;
RMATCH(eptr, ecode + PRIV(OP_lengths)[*ecode], offset_top, mb, eptrb,
RM2);
/* See comment in the code for capturing groups above about handling
THEN. */
if (rrc == MATCH_THEN)
{
next_ecode = ecode + GET(ecode,1);
if (mb->start_match_ptr < next_ecode &&
(*ecode == OP_ALT || *next_ecode == OP_ALT))
rrc = MATCH_NOMATCH;
}
if (rrc != MATCH_NOMATCH)
{
if (rrc == MATCH_ONCE)
{
PCRE2_SPTR scode = ecode;
if (*scode != OP_ONCE) /* If not at start, find it */
{
while (*scode == OP_ALT) scode += GET(scode, 1);
scode -= GET(scode, 1);
}
if (mb->once_target == scode) rrc = MATCH_NOMATCH;
}
RRETURN(rrc);
}
ecode += GET(ecode, 1);
mb->mark = save_mark;
if (*ecode != OP_ALT) break;
mb->capture_last = save_capture_last;
}
RRETURN(MATCH_NOMATCH);
/* Handle possessive capturing brackets with an unlimited repeat. We come
here from BRAZERO with allow_zero set TRUE. The ovector values are
handled similarly to the normal case above. However, the matching is
different. The end of these brackets will always be OP_KETRPOS, which
returns MATCH_KETRPOS without going further in the pattern. By this means
we can handle the group by iteration rather than recursion, thereby
reducing the amount of stack needed. If the ovector is too small for
capturing, treat as non-capturing. */
case OP_CBRAPOS:
case OP_SCBRAPOS:
allow_zero = FALSE;
POSSESSIVE_CAPTURE:
number = GET2(ecode, 1+LINK_SIZE);
offset = number << 1;
if (offset >= mb->offset_max) goto POSSESSIVE_NON_CAPTURE;
matched_once = FALSE;
code_offset = (int)(ecode - mb->start_code);
save_offset1 = mb->ovector[offset];
save_offset2 = mb->ovector[offset+1];
save_offset3 = mb->ovector[mb->offset_end - number];
save_capture_last = mb->capture_last;
/* Each time round the loop, save the current subject position for use
when the group matches. For MATCH_MATCH, the group has matched, so we
restart it with a new subject starting position, remembering that we had
at least one match. For MATCH_NOMATCH, carry on with the alternatives, as
usual. If we haven't matched any alternatives in any iteration, check to
see if a previous iteration matched. If so, the group has matched;
continue from afterwards. Otherwise it has failed; restore the previous
capture values before returning NOMATCH. */
for (;;)
{
mb->ovector[mb->offset_end - number] = eptr - mb->start_subject;
if (op >= OP_SBRA) mb->match_function_type |= MATCH_CBEGROUP;
RMATCH(eptr, ecode + PRIV(OP_lengths)[*ecode], offset_top, mb,
eptrb, RM63);
if (rrc == MATCH_KETRPOS)
{
offset_top = mb->end_offset_top;
ecode = mb->start_code + code_offset;
save_capture_last = mb->capture_last;
matched_once = TRUE;
mstart = mb->start_match_ptr; /* In case \K changed it */
if (eptr == mb->end_match_ptr) /* Matched an empty string */
{
do ecode += GET(ecode, 1); while (*ecode == OP_ALT);
break;
}
eptr = mb->end_match_ptr;
continue;
}
/* See comment in the code for capturing groups above about handling
THEN. */
if (rrc == MATCH_THEN)
{
next_ecode = ecode + GET(ecode,1);
if (mb->start_match_ptr < next_ecode &&
(*ecode == OP_ALT || *next_ecode == OP_ALT))
rrc = MATCH_NOMATCH;
}
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
mb->capture_last = save_capture_last;
ecode += GET(ecode, 1);
if (*ecode != OP_ALT) break;
}
if (!matched_once)
{
mb->ovector[offset] = save_offset1;
mb->ovector[offset+1] = save_offset2;
mb->ovector[mb->offset_end - number] = save_offset3;
}
if (allow_zero || matched_once)
{
ecode += 1 + LINK_SIZE;
break;
}
RRETURN(MATCH_NOMATCH);
/* Non-capturing possessive bracket with unlimited repeat. We come here
from BRAZERO with allow_zero = TRUE. The code is similar to the above,
without the capturing complication. It is written out separately for speed
and cleanliness. */
case OP_BRAPOS:
case OP_SBRAPOS:
allow_zero = FALSE;
POSSESSIVE_NON_CAPTURE:
matched_once = FALSE;
code_offset = (int)(ecode - mb->start_code);
save_capture_last = mb->capture_last;
for (;;)
{
if (op >= OP_SBRA) mb->match_function_type |= MATCH_CBEGROUP;
RMATCH(eptr, ecode + PRIV(OP_lengths)[*ecode], offset_top, mb,
eptrb, RM48);
if (rrc == MATCH_KETRPOS)
{
offset_top = mb->end_offset_top;
ecode = mb->start_code + code_offset;
matched_once = TRUE;
mstart = mb->start_match_ptr; /* In case \K reset it */
if (eptr == mb->end_match_ptr) /* Matched an empty string */
{
do ecode += GET(ecode, 1); while (*ecode == OP_ALT);
break;
}
eptr = mb->end_match_ptr;
continue;
}
/* See comment in the code for capturing groups above about handling
THEN. */
if (rrc == MATCH_THEN)
{
next_ecode = ecode + GET(ecode,1);
if (mb->start_match_ptr < next_ecode &&
(*ecode == OP_ALT || *next_ecode == OP_ALT))
rrc = MATCH_NOMATCH;
}
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
ecode += GET(ecode, 1);
if (*ecode != OP_ALT) break;
mb->capture_last = save_capture_last;
}
if (matched_once || allow_zero)
{
ecode += 1 + LINK_SIZE;
break;
}
RRETURN(MATCH_NOMATCH);
/* Control never reaches here. */
/* Conditional group: compilation checked that there are no more than two
branches. If the condition is false, skipping the first branch takes us
past the end of the item if there is only one branch, but that's exactly
what we want. */
case OP_COND:
case OP_SCOND:
/* The variable codelink will be added to ecode when the condition is
false, to get to the second branch. Setting it to the offset to the ALT
or KET, then incrementing ecode achieves this effect. We now have ecode
pointing to the condition or callout. */
codelink = GET(ecode, 1); /* Offset to the second branch */
ecode += 1 + LINK_SIZE; /* From this opcode */
/* Because of the way auto-callout works during compile, a callout item is
inserted between OP_COND and an assertion condition. */
if (*ecode == OP_CALLOUT || *ecode == OP_CALLOUT_STR)
{
unsigned int callout_length = (*ecode == OP_CALLOUT)
? PRIV(OP_lengths)[OP_CALLOUT] : GET(ecode, 1 + 2*LINK_SIZE);
if (mb->callout != NULL)
{
pcre2_callout_block cb;
cb.version = 1;
cb.capture_top = offset_top/2;
cb.capture_last = mb->capture_last & CAPLMASK;
cb.offset_vector = mb->ovector;
cb.mark = mb->nomatch_mark;
cb.subject = mb->start_subject;
cb.subject_length = (PCRE2_SIZE)(mb->end_subject - mb->start_subject);
cb.start_match = (PCRE2_SIZE)(mstart - mb->start_subject);
cb.current_position = (PCRE2_SIZE)(eptr - mb->start_subject);
cb.pattern_position = GET(ecode, 1);
cb.next_item_length = GET(ecode, 1 + LINK_SIZE);
if (*ecode == OP_CALLOUT)
{
cb.callout_number = ecode[1 + 2*LINK_SIZE];
cb.callout_string_offset = 0;
cb.callout_string = NULL;
cb.callout_string_length = 0;
}
else
{
cb.callout_number = 0;
cb.callout_string_offset = GET(ecode, 1 + 3*LINK_SIZE);
cb.callout_string = ecode + (1 + 4*LINK_SIZE) + 1;
cb.callout_string_length =
callout_length - (1 + 4*LINK_SIZE) - 2;
}
if ((rrc = mb->callout(&cb, mb->callout_data)) > 0)
RRETURN(MATCH_NOMATCH);
if (rrc < 0) RRETURN(rrc);
}
/* Advance ecode past the callout, so it now points to the condition. We
must adjust codelink so that the value of ecode+codelink is unchanged. */
ecode += callout_length;
codelink -= callout_length;
}
/* Test the various possible conditions */
condition = FALSE;
switch(condcode = *ecode)
{
case OP_RREF: /* Numbered group recursion test */
if (mb->recursive != NULL) /* Not recursing => FALSE */
{
uint32_t recno = GET2(ecode, 1); /* Recursion group number*/
condition = (recno == RREF_ANY || recno == mb->recursive->group_num);
}
break;
case OP_DNRREF: /* Duplicate named group recursion test */
if (mb->recursive != NULL)
{
int count = GET2(ecode, 1 + IMM2_SIZE);
PCRE2_SPTR slot = mb->name_table + GET2(ecode, 1) * mb->name_entry_size;
while (count-- > 0)
{
uint32_t recno = GET2(slot, 0);
condition = recno == mb->recursive->group_num;
if (condition) break;
slot += mb->name_entry_size;
}
}
break;
case OP_CREF: /* Numbered group used test */
offset = GET2(ecode, 1) << 1; /* Doubled ref number */
condition = offset < offset_top &&
mb->ovector[offset] != PCRE2_UNSET;
break;
case OP_DNCREF: /* Duplicate named group used test */
{
int count = GET2(ecode, 1 + IMM2_SIZE);
PCRE2_SPTR slot = mb->name_table + GET2(ecode, 1) * mb->name_entry_size;
while (count-- > 0)
{
offset = GET2(slot, 0) << 1;
condition = offset < offset_top &&
mb->ovector[offset] != PCRE2_UNSET;
if (condition) break;
slot += mb->name_entry_size;
}
}
break;
case OP_FALSE:
case OP_FAIL: /* The assertion (?!) becomes OP_FAIL */
break;
case OP_TRUE:
condition = TRUE;
break;
/* The condition is an assertion. Call match() to evaluate it - setting
the MATCH_CONDASSERT bit in mb->match_function_type causes it to stop at
the end of an assertion. */
default:
mb->match_function_type |= MATCH_CONDASSERT;
RMATCH(eptr, ecode, offset_top, mb, NULL, RM3);
if (rrc == MATCH_MATCH)
{
if (mb->end_offset_top > offset_top)
offset_top = mb->end_offset_top; /* Captures may have happened */
condition = TRUE;
/* Advance ecode past the assertion to the start of the first branch,
but adjust it so that the general choosing code below works. If the
assertion has a quantifier that allows zero repeats we must skip over
the BRAZERO. This is a lunatic thing to do, but somebody did! */
if (*ecode == OP_BRAZERO) ecode++;
ecode += GET(ecode, 1);
while (*ecode == OP_ALT) ecode += GET(ecode, 1);
ecode += 1 + LINK_SIZE - PRIV(OP_lengths)[condcode];
}
/* PCRE doesn't allow the effect of (*THEN) to escape beyond an
assertion; it is therefore treated as NOMATCH. Any other return is an
error. */
else if (rrc != MATCH_NOMATCH && rrc != MATCH_THEN)
{
RRETURN(rrc); /* Need braces because of following else */
}
break;
}
/* Choose branch according to the condition */
ecode += condition? PRIV(OP_lengths)[condcode] : codelink;
/* We are now at the branch that is to be obeyed. As there is only one, we
can use tail recursion to avoid using another stack frame, except when
there is unlimited repeat of a possibly empty group. In the latter case, a
recursive call to match() is always required, unless the second alternative
doesn't exist, in which case we can just plough on. Note that, for
compatibility with Perl, the | in a conditional group is NOT treated as
creating two alternatives. If a THEN is encountered in the branch, it
propagates out to the enclosing alternative (unless nested in a deeper set
of alternatives, of course). */
if (condition || ecode[-(1+LINK_SIZE)] == OP_ALT)
{
if (op != OP_SCOND)
{
goto TAIL_RECURSE;
}
mb->match_function_type |= MATCH_CBEGROUP;
RMATCH(eptr, ecode, offset_top, mb, eptrb, RM49);
RRETURN(rrc);
}
/* Condition false & no alternative; continue after the group. */
else
{
}
break;
/* Before OP_ACCEPT there may be any number of OP_CLOSE opcodes,
to close any currently open capturing brackets. */
case OP_CLOSE:
number = GET2(ecode, 1); /* Must be less than 65536 */
offset = number << 1;
mb->capture_last = (mb->capture_last & OVFLMASK) | number;
if (offset >= mb->offset_max) mb->capture_last |= OVFLBIT; else
{
mb->ovector[offset] =
mb->ovector[mb->offset_end - number];
mb->ovector[offset+1] = eptr - mb->start_subject;
/* If this group is at or above the current highwater mark, ensure that
any groups between the current high water mark and this group are marked
unset and then update the high water mark. */
if (offset >= offset_top)
{
register PCRE2_SIZE *iptr = mb->ovector + offset_top;
register PCRE2_SIZE *iend = mb->ovector + offset;
while (iptr < iend) *iptr++ = PCRE2_UNSET;
offset_top = offset + 2;
}
}
ecode += 1 + IMM2_SIZE;
break;
/* End of the pattern, either real or forced. In an assertion ACCEPT,
update the last used pointer. */
case OP_ASSERT_ACCEPT:
if (eptr > mb->last_used_ptr) mb->last_used_ptr = eptr;
case OP_ACCEPT:
case OP_END:
/* If we have matched an empty string, fail if not in an assertion and not
in a recursion if either PCRE2_NOTEMPTY is set, or if PCRE2_NOTEMPTY_ATSTART
is set and we have matched at the start of the subject. In both cases,
backtracking will then try other alternatives, if any. */
if (eptr == mstart && op != OP_ASSERT_ACCEPT &&
mb->recursive == NULL &&
((mb->moptions & PCRE2_NOTEMPTY) != 0 ||
((mb->moptions & PCRE2_NOTEMPTY_ATSTART) != 0 &&
mstart == mb->start_subject + mb->start_offset)))
RRETURN(MATCH_NOMATCH);
/* Otherwise, we have a match. */
mb->end_match_ptr = eptr; /* Record where we ended */
mb->end_offset_top = offset_top; /* and how many extracts were taken */
mb->start_match_ptr = mstart; /* and the start (\K can modify) */
/* For some reason, the macros don't work properly if an expression is
given as the argument to RRETURN when the heap is in use. */
rrc = (op == OP_END)? MATCH_MATCH : MATCH_ACCEPT;
RRETURN(rrc);
/* Assertion brackets. Check the alternative branches in turn - the
matching won't pass the KET for an assertion. If any one branch matches,
the assertion is true. Lookbehind assertions have an OP_REVERSE item at the
start of each branch to move the current point backwards, so the code at
this level is identical to the lookahead case. When the assertion is part
of a condition, we want to return immediately afterwards. The caller of
this incarnation of the match() function will have set MATCH_CONDASSERT in
mb->match_function type, and one of these opcodes will be the first opcode
that is processed. We use a local variable that is preserved over calls to
match() to remember this case. */
case OP_ASSERT:
case OP_ASSERTBACK:
save_mark = mb->mark;
if ((mb->match_function_type & MATCH_CONDASSERT) != 0)
{
condassert = TRUE;
mb->match_function_type &= ~MATCH_CONDASSERT;
}
else condassert = FALSE;
/* Loop for each branch */
do
{
RMATCH(eptr, ecode + 1 + LINK_SIZE, offset_top, mb, NULL, RM4);
/* A match means that the assertion is true; break out of the loop
that matches its alternatives. */
if (rrc == MATCH_MATCH || rrc == MATCH_ACCEPT)
{
mstart = mb->start_match_ptr; /* In case \K reset it */
break;
}
/* If not matched, restore the previous mark setting. */
mb->mark = save_mark;
/* See comment in the code for capturing groups above about handling
THEN. */
if (rrc == MATCH_THEN)
{
next_ecode = ecode + GET(ecode,1);
if (mb->start_match_ptr < next_ecode &&
(*ecode == OP_ALT || *next_ecode == OP_ALT))
rrc = MATCH_NOMATCH;
}
/* Anything other than NOMATCH causes the entire assertion to fail,
passing back the return code. This includes COMMIT, SKIP, PRUNE and an
uncaptured THEN, which means they take their normal effect. This
consistent approach does not always have exactly the same effect as in
Perl. */
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
ecode += GET(ecode, 1);
}
while (*ecode == OP_ALT); /* Continue for next alternative */
/* If we have tried all the alternative branches, the assertion has
failed. If not, we broke out after a match. */
if (*ecode == OP_KET) RRETURN(MATCH_NOMATCH);
/* If checking an assertion for a condition, return MATCH_MATCH. */
if (condassert) RRETURN(MATCH_MATCH);
/* Continue from after a successful assertion, updating the offsets high
water mark, since extracts may have been taken during the assertion. */
do ecode += GET(ecode,1); while (*ecode == OP_ALT);
ecode += 1 + LINK_SIZE;
offset_top = mb->end_offset_top;
continue;
/* Negative assertion: all branches must fail to match for the assertion to
succeed. */
case OP_ASSERT_NOT:
case OP_ASSERTBACK_NOT:
save_mark = mb->mark;
if ((mb->match_function_type & MATCH_CONDASSERT) != 0)
{
condassert = TRUE;
mb->match_function_type &= ~MATCH_CONDASSERT;
}
else condassert = FALSE;
/* Loop for each alternative branch. */
do
{
RMATCH(eptr, ecode + 1 + LINK_SIZE, offset_top, mb, NULL, RM5);
mb->mark = save_mark; /* Always restore the mark setting */
switch(rrc)
{
case MATCH_MATCH: /* A successful match means */
case MATCH_ACCEPT: /* the assertion has failed. */
RRETURN(MATCH_NOMATCH);
case MATCH_NOMATCH: /* Carry on with next branch */
break;
/* See comment in the code for capturing groups above about handling
THEN. */
case MATCH_THEN:
next_ecode = ecode + GET(ecode,1);
if (mb->start_match_ptr < next_ecode &&
(*ecode == OP_ALT || *next_ecode == OP_ALT))
{
rrc = MATCH_NOMATCH;
break;
}
/* Otherwise fall through. */
/* COMMIT, SKIP, PRUNE, and an uncaptured THEN cause the whole
assertion to fail to match, without considering any more alternatives.
Failing to match means the assertion is true. This is a consistent
approach, but does not always have the same effect as in Perl. */
case MATCH_COMMIT:
case MATCH_SKIP:
case MATCH_SKIP_ARG:
case MATCH_PRUNE:
do ecode += GET(ecode,1); while (*ecode == OP_ALT);
goto NEG_ASSERT_TRUE; /* Break out of alternation loop */
/* Anything else is an error */
default:
RRETURN(rrc);
}
/* Continue with next branch */
ecode += GET(ecode,1);
}
while (*ecode == OP_ALT);
/* All branches in the assertion failed to match. */
NEG_ASSERT_TRUE:
if (condassert) RRETURN(MATCH_MATCH); /* Condition assertion */
ecode += 1 + LINK_SIZE; /* Continue with current branch */
continue;
/* Move the subject pointer back. This occurs only at the start of
each branch of a lookbehind assertion. If we are too close to the start to
move back, this match function fails. When working with UTF-8 we move
back a number of characters, not bytes. */
case OP_REVERSE:
i = GET(ecode, 1);
#ifdef SUPPORT_UNICODE
if (utf)
{
while (i-- > 0)
{
if (eptr <= mb->start_subject) RRETURN(MATCH_NOMATCH);
eptr--;
BACKCHAR(eptr);
}
}
else
#endif
/* No UTF-8 support, or not in UTF-8 mode: count is byte count */
{
if (i > eptr - mb->start_subject) RRETURN(MATCH_NOMATCH);
eptr -= i;
}
/* Save the earliest consulted character, then skip to next op code */
if (eptr < mb->start_used_ptr) mb->start_used_ptr = eptr;
ecode += 1 + LINK_SIZE;
break;
/* The callout item calls an external function, if one is provided, passing
details of the match so far. This is mainly for debugging, though the
function is able to force a failure. */
case OP_CALLOUT:
case OP_CALLOUT_STR:
{
unsigned int callout_length = (*ecode == OP_CALLOUT)
? PRIV(OP_lengths)[OP_CALLOUT] : GET(ecode, 1 + 2*LINK_SIZE);
if (mb->callout != NULL)
{
pcre2_callout_block cb;
cb.version = 1;
cb.callout_number = ecode[LINK_SIZE + 1];
cb.capture_top = offset_top/2;
cb.capture_last = mb->capture_last & CAPLMASK;
cb.offset_vector = mb->ovector;
cb.mark = mb->nomatch_mark;
cb.subject = mb->start_subject;
cb.subject_length = (PCRE2_SIZE)(mb->end_subject - mb->start_subject);
cb.start_match = (PCRE2_SIZE)(mstart - mb->start_subject);
cb.current_position = (PCRE2_SIZE)(eptr - mb->start_subject);
cb.pattern_position = GET(ecode, 1);
cb.next_item_length = GET(ecode, 1 + LINK_SIZE);
if (*ecode == OP_CALLOUT)
{
cb.callout_number = ecode[1 + 2*LINK_SIZE];
cb.callout_string_offset = 0;
cb.callout_string = NULL;
cb.callout_string_length = 0;
}
else
{
cb.callout_number = 0;
cb.callout_string_offset = GET(ecode, 1 + 3*LINK_SIZE);
cb.callout_string = ecode + (1 + 4*LINK_SIZE) + 1;
cb.callout_string_length =
callout_length - (1 + 4*LINK_SIZE) - 2;
}
if ((rrc = mb->callout(&cb, mb->callout_data)) > 0)
RRETURN(MATCH_NOMATCH);
if (rrc < 0) RRETURN(rrc);
}
ecode += callout_length;
}
break;
/* Recursion either matches the current regex, or some subexpression. The
offset data is the offset to the starting bracket from the start of the
whole pattern. (This is so that it works from duplicated subpatterns.)
The state of the capturing groups is preserved over recursion, and
re-instated afterwards. We don't know how many are started and not yet
finished (offset_top records the completed total) so we just have to save
all the potential data. There may be up to 65535 such values, which is too
large to put on the stack, but using malloc for small numbers seems
expensive. As a compromise, the stack is used when there are no more than
OP_RECURSE_STACK_SAVE_MAX values to store; otherwise malloc is used.
There are also other values that have to be saved. We use a chained
sequence of blocks that actually live on the stack. Thanks to Robin Houston
for the original version of this logic. It has, however, been hacked around
a lot, so he is not to blame for the current way it works. */
case OP_RECURSE:
{
ovecsave_frame *fr;
recursion_info *ri;
uint32_t recno;
callpat = mb->start_code + GET(ecode, 1);
recno = (callpat == mb->start_code)? 0 : GET2(callpat, 1 + LINK_SIZE);
/* Check for repeating a pattern recursion without advancing the subject
pointer. This should catch convoluted mutual recursions. (Some simple
cases are caught at compile time.) */
for (ri = mb->recursive; ri != NULL; ri = ri->prevrec)
if (recno == ri->group_num && eptr == ri->subject_position)
RRETURN(PCRE2_ERROR_RECURSELOOP);
/* Add to "recursing stack" */
new_recursive.group_num = recno;
new_recursive.saved_capture_last = mb->capture_last;
new_recursive.subject_position = eptr;
new_recursive.prevrec = mb->recursive;
mb->recursive = &new_recursive;
/* Where to continue from afterwards */
ecode += 1 + LINK_SIZE;
/* When we are using the system stack for match() recursion we can call a
function that uses the system stack for preserving the ovector while
processing the pattern recursion, but only if the ovector is small
enough. */
#ifndef HEAP_MATCH_RECURSE
if (mb->offset_end <= OP_RECURSE_STACK_SAVE_MAX)
{
rrc = op_recurse_ovecsave(eptr, callpat, mstart, offset_top, mb,
eptrb, rdepth);
mb->recursive = new_recursive.prevrec;
if (rrc != MATCH_MATCH && rrc != MATCH_ACCEPT) RRETURN(rrc);
/* Set where we got to in the subject, and reset the start, in case
it was changed by \K. This *is* propagated back out of a recursion,
for Perl compatibility. */
eptr = mb->end_match_ptr;
mstart = mb->start_match_ptr;
break; /* End of processing OP_RECURSE */
}
#endif
/* If the ovector is too big, or if we are using the heap for match()
recursion, we have to use the heap for saving the ovector. Used ovecsave
frames are kept on a chain and re-used. This makes a small improvement in
execution time on Linux. */
if (mb->ovecsave_chain != NULL)
{
new_recursive.ovec_save = mb->ovecsave_chain->saved_ovec;
mb->ovecsave_chain = mb->ovecsave_chain->next;
}
else
{
fr = (ovecsave_frame *)(mb->memctl.malloc(sizeof(ovecsave_frame *) +
mb->offset_end * sizeof(PCRE2_SIZE), mb->memctl.memory_data));
if (fr == NULL) RRETURN(PCRE2_ERROR_NOMEMORY);
new_recursive.ovec_save = fr->saved_ovec;
}
memcpy(new_recursive.ovec_save, mb->ovector,
mb->offset_end * sizeof(PCRE2_SIZE));
/* Do the recursion. After processing each alternative, restore the
ovector data and the last captured value. This code has the same overall
logic as the code in the op_recurse_ovecsave() function, but is adapted
to use RMATCH/RRETURN and to release the heap block containing the saved
ovector. */
cbegroup = (*callpat >= OP_SBRA);
do
{
if (cbegroup) mb->match_function_type |= MATCH_CBEGROUP;
RMATCH(eptr, callpat + PRIV(OP_lengths)[*callpat], offset_top,
mb, eptrb, RM6);
memcpy(mb->ovector, new_recursive.ovec_save,
mb->offset_end * sizeof(PCRE2_SIZE));
mb->capture_last = new_recursive.saved_capture_last;
mb->recursive = new_recursive.prevrec;
if (rrc == MATCH_MATCH || rrc == MATCH_ACCEPT)
{
fr = (ovecsave_frame *)
((uint8_t *)new_recursive.ovec_save - sizeof(ovecsave_frame *));
fr->next = mb->ovecsave_chain;
mb->ovecsave_chain = fr;
/* Set where we got to in the subject, and reset the start, in case
it was changed by \K. This *is* propagated back out of a recursion,
for Perl compatibility. */
eptr = mb->end_match_ptr;
mstart = mb->start_match_ptr;
goto RECURSION_MATCHED; /* Exit loop; end processing */
}
/* PCRE does not allow THEN, SKIP, PRUNE or COMMIT to escape beyond a
recursion; they cause a NOMATCH for the entire recursion. These codes
are defined in a range that can be tested for. */
if (rrc >= MATCH_BACKTRACK_MIN && rrc <= MATCH_BACKTRACK_MAX)
{
rrc = MATCH_NOMATCH;
goto RECURSION_RETURN;
}
/* Any return code other than NOMATCH is an error. */
if (rrc != MATCH_NOMATCH) goto RECURSION_RETURN;
mb->recursive = &new_recursive;
callpat += GET(callpat, 1);
}
while (*callpat == OP_ALT);
RECURSION_RETURN:
mb->recursive = new_recursive.prevrec;
fr = (ovecsave_frame *)
((uint8_t *)new_recursive.ovec_save - sizeof(ovecsave_frame *));
fr->next = mb->ovecsave_chain;
mb->ovecsave_chain = fr;
RRETURN(rrc);
}
RECURSION_MATCHED:
break;
/* An alternation is the end of a branch; scan along to find the end of the
bracketed group and go to there. */
case OP_ALT:
do ecode += GET(ecode,1); while (*ecode == OP_ALT);
break;
/* BRAZERO, BRAMINZERO and SKIPZERO occur just before a bracket group,
indicating that it may occur zero times. It may repeat infinitely, or not
at all - i.e. it could be ()* or ()? or even (){0} in the pattern. Brackets
with fixed upper repeat limits are compiled as a number of copies, with the
optional ones preceded by BRAZERO or BRAMINZERO. */
case OP_BRAZERO:
next_ecode = ecode + 1;
RMATCH(eptr, next_ecode, offset_top, mb, eptrb, RM10);
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
do next_ecode += GET(next_ecode, 1); while (*next_ecode == OP_ALT);
ecode = next_ecode + 1 + LINK_SIZE;
break;
case OP_BRAMINZERO:
next_ecode = ecode + 1;
do next_ecode += GET(next_ecode, 1); while (*next_ecode == OP_ALT);
RMATCH(eptr, next_ecode + 1+LINK_SIZE, offset_top, mb, eptrb, RM11);
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
ecode++;
break;
case OP_SKIPZERO:
next_ecode = ecode+1;
do next_ecode += GET(next_ecode,1); while (*next_ecode == OP_ALT);
ecode = next_ecode + 1 + LINK_SIZE;
break;
/* BRAPOSZERO occurs before a possessive bracket group. Don't do anything
here; just jump to the group, with allow_zero set TRUE. */
case OP_BRAPOSZERO:
op = *(++ecode);
allow_zero = TRUE;
if (op == OP_CBRAPOS || op == OP_SCBRAPOS) goto POSSESSIVE_CAPTURE;
goto POSSESSIVE_NON_CAPTURE;
/* End of a group, repeated or non-repeating. */
case OP_KET:
case OP_KETRMIN:
case OP_KETRMAX:
case OP_KETRPOS:
prev = ecode - GET(ecode, 1);
/* If this was a group that remembered the subject start, in order to break
infinite repeats of empty string matches, retrieve the subject start from
the chain. Otherwise, set it NULL. */
if (*prev >= OP_SBRA || *prev == OP_ONCE)
{
saved_eptr = eptrb->epb_saved_eptr; /* Value at start of group */
eptrb = eptrb->epb_prev; /* Backup to previous group */
}
else saved_eptr = NULL;
/* If we are at the end of an assertion group or a non-capturing atomic
group, stop matching and return MATCH_MATCH, but record the current high
water mark for use by positive assertions. We also need to record the match
start in case it was changed by \K. */
if ((*prev >= OP_ASSERT && *prev <= OP_ASSERTBACK_NOT) ||
*prev == OP_ONCE_NC)
{
mb->end_match_ptr = eptr; /* For ONCE_NC */
mb->end_offset_top = offset_top;
mb->start_match_ptr = mstart;
if (eptr > mb->last_used_ptr) mb->last_used_ptr = eptr;
RRETURN(MATCH_MATCH); /* Sets mb->mark */
}
/* For capturing groups we have to check the group number back at the start
and if necessary complete handling an extraction by setting the offsets and
bumping the high water mark. Whole-pattern recursion is coded as a recurse
into group 0, so it won't be picked up here. Instead, we catch it when the
OP_END is reached. Other recursion is handled here. We just have to record
the current subject position and start match pointer and give a MATCH
return. */
if (*prev == OP_CBRA || *prev == OP_SCBRA ||
*prev == OP_CBRAPOS || *prev == OP_SCBRAPOS)
{
number = GET2(prev, 1+LINK_SIZE);
offset = number << 1;
/* Handle a recursively called group. */
if (mb->recursive != NULL && mb->recursive->group_num == number)
{
mb->end_match_ptr = eptr;
mb->start_match_ptr = mstart;
if (eptr > mb->last_used_ptr) mb->last_used_ptr = eptr;
RRETURN(MATCH_MATCH);
}
/* Deal with capturing */
mb->capture_last = (mb->capture_last & OVFLMASK) | number;
if (offset >= mb->offset_max) mb->capture_last |= OVFLBIT; else
{
/* If offset is greater than offset_top, it means that we are
"skipping" a capturing group, and that group's offsets must be marked
unset. In earlier versions of PCRE, all the offsets were unset at the
start of matching, but this doesn't work because atomic groups and
assertions can cause a value to be set that should later be unset.
Example: matching /(?>(a))b|(a)c/ against "ac". This sets group 1 as
part of the atomic group, but this is not on the final matching path,
so must be unset when 2 is set. (If there is no group 2, there is no
problem, because offset_top will then be 2, indicating no capture.) */
if (offset > offset_top)
{
register PCRE2_SIZE *iptr = mb->ovector + offset_top;
register PCRE2_SIZE *iend = mb->ovector + offset;
while (iptr < iend) *iptr++ = PCRE2_UNSET;
}
/* Now make the extraction */
mb->ovector[offset] = mb->ovector[mb->offset_end - number];
mb->ovector[offset+1] = eptr - mb->start_subject;
if (offset_top <= offset) offset_top = offset + 2;
}
}
/* OP_KETRPOS is a possessive repeating ket. Remember the current position,
and return the MATCH_KETRPOS. This makes it possible to do the repeats one
at a time from the outer level, thus saving stack. This must precede the
empty string test - in this case that test is done at the outer level. */
if (*ecode == OP_KETRPOS)
{
mb->start_match_ptr = mstart; /* In case \K reset it */
mb->end_match_ptr = eptr;
mb->end_offset_top = offset_top;
if (eptr > mb->last_used_ptr) mb->last_used_ptr = eptr;
RRETURN(MATCH_KETRPOS);
}
/* For an ordinary non-repeating ket, just continue at this level. This
also happens for a repeating ket if no characters were matched in the
group. This is the forcible breaking of infinite loops as implemented in
Perl 5.005. For a non-repeating atomic group that includes captures,
establish a backup point by processing the rest of the pattern at a lower
level. If this results in a NOMATCH return, pass MATCH_ONCE back to the
original OP_ONCE level, thereby bypassing intermediate backup points, but
resetting any captures that happened along the way. */
if (*ecode == OP_KET || eptr == saved_eptr)
{
if (*prev == OP_ONCE)
{
RMATCH(eptr, ecode + 1 + LINK_SIZE, offset_top, mb, eptrb, RM12);
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
mb->once_target = prev; /* Level at which to change to MATCH_NOMATCH */
RRETURN(MATCH_ONCE);
}
ecode += 1 + LINK_SIZE; /* Carry on at this level */
break;
}
/* The normal repeating kets try the rest of the pattern or restart from
the preceding bracket, in the appropriate order. In the second case, we can
use tail recursion to avoid using another stack frame, unless we have an
an atomic group or an unlimited repeat of a group that can match an empty
string. */
if (*ecode == OP_KETRMIN)
{
RMATCH(eptr, ecode + 1 + LINK_SIZE, offset_top, mb, eptrb, RM7);
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
if (*prev == OP_ONCE)
{
RMATCH(eptr, prev, offset_top, mb, eptrb, RM8);
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
mb->once_target = prev; /* Level at which to change to MATCH_NOMATCH */
RRETURN(MATCH_ONCE);
}
if (*prev >= OP_SBRA) /* Could match an empty string */
{
RMATCH(eptr, prev, offset_top, mb, eptrb, RM50);
RRETURN(rrc);
}
ecode = prev;
goto TAIL_RECURSE;
}
else /* OP_KETRMAX */
{
RMATCH(eptr, prev, offset_top, mb, eptrb, RM13);
if (rrc == MATCH_ONCE && mb->once_target == prev) rrc = MATCH_NOMATCH;
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
if (*prev == OP_ONCE)
{
RMATCH(eptr, ecode + 1 + LINK_SIZE, offset_top, mb, eptrb, RM9);
if (rrc != MATCH_NOMATCH) RRETURN(rrc);
mb->once_target = prev;
RRETURN(MATCH_ONCE);
}
ecode += 1 + LINK_SIZE;
goto TAIL_RECURSE;
}
/* Control never gets here */
/* Not multiline mode: start of subject assertion, unless notbol. */
case OP_CIRC:
if ((mb->moptions & PCRE2_NOTBOL) != 0 && eptr == mb->start_subject)
RRETURN(MATCH_NOMATCH);
/* Start of subject assertion */
case OP_SOD:
if (eptr != mb->start_subject) RRETURN(MATCH_NOMATCH);
ecode++;
break;
/* Multiline mode: start of subject unless notbol, or after any newline
except for one at the very end, unless PCRE2_ALT_CIRCUMFLEX is set. */
case OP_CIRCM:
if ((mb->moptions & PCRE2_NOTBOL) != 0 && eptr == mb->start_subject)
RRETURN(MATCH_NOMATCH);
if (eptr != mb->start_subject &&
((eptr == mb->end_subject &&
(mb->poptions & PCRE2_ALT_CIRCUMFLEX) == 0) ||
!WAS_NEWLINE(eptr)))
RRETURN(MATCH_NOMATCH);
ecode++;
break;
/* Start of match assertion */
case OP_SOM:
if (eptr != mb->start_subject + mb->start_offset) RRETURN(MATCH_NOMATCH);
ecode++;
break;
/* Reset the start of match point */
case OP_SET_SOM:
mstart = eptr;
ecode++;
break;
/* Multiline mode: assert before any newline, or before end of subject
unless noteol is set. */
case OP_DOLLM:
if (eptr < mb->end_subject)
{
if (!IS_NEWLINE(eptr))
{
if (mb->partial != 0 &&
eptr + 1 >= mb->end_subject &&
NLBLOCK->nltype == NLTYPE_FIXED &&
NLBLOCK->nllen == 2 &&
UCHAR21TEST(eptr) == NLBLOCK->nl[0])
{
mb->hitend = TRUE;
if (mb->partial > 1) RRETURN(PCRE2_ERROR_PARTIAL);
}
RRETURN(MATCH_NOMATCH);
}
}
else
{
if ((mb->moptions & PCRE2_NOTEOL) != 0) RRETURN(MATCH_NOMATCH);
SCHECK_PARTIAL();
}
ecode++;
break;
/* Not multiline mode: assert before a terminating newline or before end of
subject unless noteol is set. */
case OP_DOLL:
if ((mb->moptions & PCRE2_NOTEOL) != 0) RRETURN(MATCH_NOMATCH);
if ((mb->poptions & PCRE2_DOLLAR_ENDONLY) == 0) goto ASSERT_NL_OR_EOS;
/* ... else fall through for endonly */
/* End of subject assertion (\z) */
case OP_EOD:
if (eptr < mb->end_subject) RRETURN(MATCH_NOMATCH);
SCHECK_PARTIAL();
ecode++;
break;
/* End of subject or ending \n assertion (\Z) */
case OP_EODN:
ASSERT_NL_OR_EOS:
if (eptr < mb->end_subject &&
(!IS_NEWLINE(eptr) || eptr != mb->end_subject - mb->nllen))
{
if (mb->partial != 0 &&
eptr + 1 >= mb->end_subject &&
NLBLOCK->nltype == NLTYPE_FIXED &&
NLBLOCK->nllen == 2 &&
UCHAR21TEST(eptr) == NLBLOCK->nl[0])
{
mb->hitend = TRUE;
if (mb->partial > 1) RRETURN(PCRE2_ERROR_PARTIAL);
}
RRETURN(MATCH_NOMATCH);
}
/* Either at end of string or \n before end. */
SCHECK_PARTIAL();
ecode++;
break;
/* Word boundary assertions */
case OP_NOT_WORD_BOUNDARY:
case OP_WORD_BOUNDARY:
{
/* Find out if the previous and current characters are "word" characters.
It takes a bit more work in UTF-8 mode. Characters > 255 are assumed to
be "non-word" characters. Remember the earliest consulted character for
partial matching. */
#ifdef SUPPORT_UNICODE
if (utf)
{
/* Get status of previous character */
if (eptr == mb->start_subject) prev_is_word = FALSE; else
{
PCRE2_SPTR lastptr = eptr - 1;
BACKCHAR(lastptr);
if (lastptr < mb->start_used_ptr) mb->start_used_ptr = lastptr;
GETCHAR(c, lastptr);
if ((mb->poptions & PCRE2_UCP) != 0)
{
if (c == '_') prev_is_word = TRUE; else
{
int cat = UCD_CATEGORY(c);
prev_is_word = (cat == ucp_L || cat == ucp_N);
}
}
else
prev_is_word = c < 256 && (mb->ctypes[c] & ctype_word) != 0;
}
/* Get status of next character */
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
cur_is_word = FALSE;
}
else
{
PCRE2_SPTR nextptr = eptr + 1;
FORWARDCHARTEST(nextptr, mb->end_subject);
if (nextptr > mb->last_used_ptr) mb->last_used_ptr = nextptr;
GETCHAR(c, eptr);
if ((mb->poptions & PCRE2_UCP) != 0)
{
if (c == '_') cur_is_word = TRUE; else
{
int cat = UCD_CATEGORY(c);
cur_is_word = (cat == ucp_L || cat == ucp_N);
}
}
else
cur_is_word = c < 256 && (mb->ctypes[c] & ctype_word) != 0;
}
}
else
#endif /* SUPPORT UTF */
/* Not in UTF-8 mode, but we may still have PCRE2_UCP set, and for
consistency with the behaviour of \w we do use it in this case. */
{
/* Get status of previous character */
if (eptr == mb->start_subject) prev_is_word = FALSE; else
{
if (eptr <= mb->start_used_ptr) mb->start_used_ptr = eptr - 1;
#ifdef SUPPORT_UNICODE
if ((mb->poptions & PCRE2_UCP) != 0)
{
c = eptr[-1];
if (c == '_') prev_is_word = TRUE; else
{
int cat = UCD_CATEGORY(c);
prev_is_word = (cat == ucp_L || cat == ucp_N);
}
}
else
#endif
prev_is_word = MAX_255(eptr[-1])
&& ((mb->ctypes[eptr[-1]] & ctype_word) != 0);
}
/* Get status of next character */
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
cur_is_word = FALSE;
}
else
{
if (eptr >= mb->last_used_ptr) mb->last_used_ptr = eptr + 1;
#ifdef SUPPORT_UNICODE
if ((mb->poptions & PCRE2_UCP) != 0)
{
c = *eptr;
if (c == '_') cur_is_word = TRUE; else
{
int cat = UCD_CATEGORY(c);
cur_is_word = (cat == ucp_L || cat == ucp_N);
}
}
else
#endif
cur_is_word = MAX_255(*eptr)
&& ((mb->ctypes[*eptr] & ctype_word) != 0);
}
}
/* Now see if the situation is what we want */
if ((*ecode++ == OP_WORD_BOUNDARY)?
cur_is_word == prev_is_word : cur_is_word != prev_is_word)
RRETURN(MATCH_NOMATCH);
}
break;
/* Match any single character type except newline; have to take care with
CRLF newlines and partial matching. */
case OP_ANY:
if (IS_NEWLINE(eptr)) RRETURN(MATCH_NOMATCH);
if (mb->partial != 0 &&
eptr + 1 >= mb->end_subject &&
NLBLOCK->nltype == NLTYPE_FIXED &&
NLBLOCK->nllen == 2 &&
UCHAR21TEST(eptr) == NLBLOCK->nl[0])
{
mb->hitend = TRUE;
if (mb->partial > 1) RRETURN(PCRE2_ERROR_PARTIAL);
}
/* Fall through */
/* Match any single character whatsoever. */
case OP_ALLANY:
if (eptr >= mb->end_subject) /* DO NOT merge the eptr++ here; it must */
{ /* not be updated before SCHECK_PARTIAL. */
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
eptr++;
#ifdef SUPPORT_UNICODE
if (utf) ACROSSCHAR(eptr < mb->end_subject, *eptr, eptr++);
#endif
ecode++;
break;
/* Match a single code unit, even in UTF-8 mode. This opcode really does
match any code unit, even newline. (It really should be called ANYCODEUNIT,
of course - the byte name is from pre-16 bit days.) */
case OP_ANYBYTE:
if (eptr >= mb->end_subject) /* DO NOT merge the eptr++ here; it must */
{ /* not be updated before SCHECK_PARTIAL. */
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
eptr++;
ecode++;
break;
case OP_NOT_DIGIT:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
GETCHARINCTEST(c, eptr);
if (
#ifdef SUPPORT_WIDE_CHARS
c < 256 &&
#endif
(mb->ctypes[c] & ctype_digit) != 0
)
RRETURN(MATCH_NOMATCH);
ecode++;
break;
case OP_DIGIT:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
GETCHARINCTEST(c, eptr);
if (
#ifdef SUPPORT_WIDE_CHARS
c > 255 ||
#endif
(mb->ctypes[c] & ctype_digit) == 0
)
RRETURN(MATCH_NOMATCH);
ecode++;
break;
case OP_NOT_WHITESPACE:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
GETCHARINCTEST(c, eptr);
if (
#ifdef SUPPORT_WIDE_CHARS
c < 256 &&
#endif
(mb->ctypes[c] & ctype_space) != 0
)
RRETURN(MATCH_NOMATCH);
ecode++;
break;
case OP_WHITESPACE:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
GETCHARINCTEST(c, eptr);
if (
#ifdef SUPPORT_WIDE_CHARS
c > 255 ||
#endif
(mb->ctypes[c] & ctype_space) == 0
)
RRETURN(MATCH_NOMATCH);
ecode++;
break;
case OP_NOT_WORDCHAR:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
GETCHARINCTEST(c, eptr);
if (
#ifdef SUPPORT_WIDE_CHARS
c < 256 &&
#endif
(mb->ctypes[c] & ctype_word) != 0
)
RRETURN(MATCH_NOMATCH);
ecode++;
break;
case OP_WORDCHAR:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
GETCHARINCTEST(c, eptr);
if (
#ifdef SUPPORT_WIDE_CHARS
c > 255 ||
#endif
(mb->ctypes[c] & ctype_word) == 0
)
RRETURN(MATCH_NOMATCH);
ecode++;
break;
case OP_ANYNL:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
GETCHARINCTEST(c, eptr);
switch(c)
{
default: RRETURN(MATCH_NOMATCH);
case CHAR_CR:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
}
else if (UCHAR21TEST(eptr) == CHAR_LF) eptr++;
break;
case CHAR_LF:
break;
case CHAR_VT:
case CHAR_FF:
case CHAR_NEL:
#ifndef EBCDIC
case 0x2028:
case 0x2029:
#endif /* Not EBCDIC */
if (mb->bsr_convention == PCRE2_BSR_ANYCRLF) RRETURN(MATCH_NOMATCH);
break;
}
ecode++;
break;
case OP_NOT_HSPACE:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
GETCHARINCTEST(c, eptr);
switch(c)
{
HSPACE_CASES: RRETURN(MATCH_NOMATCH); /* Byte and multibyte cases */
default: break;
}
ecode++;
break;
case OP_HSPACE:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
GETCHARINCTEST(c, eptr);
switch(c)
{
HSPACE_CASES: break; /* Byte and multibyte cases */
default: RRETURN(MATCH_NOMATCH);
}
ecode++;
break;
case OP_NOT_VSPACE:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
GETCHARINCTEST(c, eptr);
switch(c)
{
VSPACE_CASES: RRETURN(MATCH_NOMATCH);
default: break;
}
ecode++;
break;
case OP_VSPACE:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
GETCHARINCTEST(c, eptr);
switch(c)
{
VSPACE_CASES: break;
default: RRETURN(MATCH_NOMATCH);
}
ecode++;
break;
#ifdef SUPPORT_UNICODE
/* Check the next character by Unicode property. We will get here only
if the support is in the binary; otherwise a compile-time error occurs. */
case OP_PROP:
case OP_NOTPROP:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
GETCHARINCTEST(c, eptr);
{
const uint32_t *cp;
const ucd_record *prop = GET_UCD(c);
switch(ecode[1])
{
case PT_ANY:
if (op == OP_NOTPROP) RRETURN(MATCH_NOMATCH);
break;
case PT_LAMP:
if ((prop->chartype == ucp_Lu ||
prop->chartype == ucp_Ll ||
prop->chartype == ucp_Lt) == (op == OP_NOTPROP))
RRETURN(MATCH_NOMATCH);
break;
case PT_GC:
if ((ecode[2] != PRIV(ucp_gentype)[prop->chartype]) == (op == OP_PROP))
RRETURN(MATCH_NOMATCH);
break;
case PT_PC:
if ((ecode[2] != prop->chartype) == (op == OP_PROP))
RRETURN(MATCH_NOMATCH);
break;
case PT_SC:
if ((ecode[2] != prop->script) == (op == OP_PROP))
RRETURN(MATCH_NOMATCH);
break;
/* These are specials */
case PT_ALNUM:
if ((PRIV(ucp_gentype)[prop->chartype] == ucp_L ||
PRIV(ucp_gentype)[prop->chartype] == ucp_N) == (op == OP_NOTPROP))
RRETURN(MATCH_NOMATCH);
break;
/* Perl space used to exclude VT, but from Perl 5.18 it is included,
which means that Perl space and POSIX space are now identical. PCRE
was changed at release 8.34. */
case PT_SPACE: /* Perl space */
case PT_PXSPACE: /* POSIX space */
switch(c)
{
HSPACE_CASES:
VSPACE_CASES:
if (op == OP_NOTPROP) RRETURN(MATCH_NOMATCH);
break;
default:
if ((PRIV(ucp_gentype)[prop->chartype] == ucp_Z) ==
(op == OP_NOTPROP)) RRETURN(MATCH_NOMATCH);
break;
}
break;
case PT_WORD:
if ((PRIV(ucp_gentype)[prop->chartype] == ucp_L ||
PRIV(ucp_gentype)[prop->chartype] == ucp_N ||
c == CHAR_UNDERSCORE) == (op == OP_NOTPROP))
RRETURN(MATCH_NOMATCH);
break;
case PT_CLIST:
cp = PRIV(ucd_caseless_sets) + ecode[2];
for (;;)
{
if (c < *cp)
{ if (op == OP_PROP) { RRETURN(MATCH_NOMATCH); } else break; }
if (c == *cp++)
{ if (op == OP_PROP) break; else { RRETURN(MATCH_NOMATCH); } }
}
break;
case PT_UCNC:
if ((c == CHAR_DOLLAR_SIGN || c == CHAR_COMMERCIAL_AT ||
c == CHAR_GRAVE_ACCENT || (c >= 0xa0 && c <= 0xd7ff) ||
c >= 0xe000) == (op == OP_NOTPROP))
RRETURN(MATCH_NOMATCH);
break;
/* This should never occur */
default:
RRETURN(PCRE2_ERROR_INTERNAL);
}
ecode += 3;
}
break;
/* Match an extended Unicode sequence. We will get here only if the support
is in the binary; otherwise a compile-time error occurs. */
case OP_EXTUNI:
if (eptr >= mb->end_subject)
{
SCHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
else
{
int lgb, rgb;
GETCHARINCTEST(c, eptr);
lgb = UCD_GRAPHBREAK(c);
while (eptr < mb->end_subject)
{
int len = 1;
if (!utf) c = *eptr; else { GETCHARLEN(c, eptr, len); }
rgb = UCD_GRAPHBREAK(c);
if ((PRIV(ucp_gbtable)[lgb] & (1 << rgb)) == 0) break;
lgb = rgb;
eptr += len;
}
}
CHECK_PARTIAL();
ecode++;
break;
#endif /* SUPPORT_UNICODE */
/* Match a back reference, possibly repeatedly. Look past the end of the
item to see if there is repeat information following.
The OP_REF and OP_REFI opcodes are used for a reference to a numbered group
or to a non-duplicated named group. For a duplicated named group, OP_DNREF
and OP_DNREFI are used. In this case we must scan the list of groups to
which the name refers, and use the first one that is set. */
case OP_DNREF:
case OP_DNREFI:
caseless = op == OP_DNREFI;
{
int count = GET2(ecode, 1+IMM2_SIZE);
PCRE2_SPTR slot = mb->name_table + GET2(ecode, 1) * mb->name_entry_size;
ecode += 1 + 2*IMM2_SIZE;
/* Initializing 'offset' avoids a compiler warning in the REF_REPEAT
code. */
offset = 0;
while (count-- > 0)
{
offset = GET2(slot, 0) << 1;
if (offset < offset_top && mb->ovector[offset] != PCRE2_UNSET) break;
slot += mb->name_entry_size;
}
}
goto REF_REPEAT;
case OP_REF:
case OP_REFI:
caseless = op == OP_REFI;
offset = GET2(ecode, 1) << 1; /* Doubled ref number */
ecode += 1 + IMM2_SIZE;
/* Set up for repetition, or handle the non-repeated case */
REF_REPEAT:
switch (*ecode)
{
case OP_CRSTAR:
case OP_CRMINSTAR:
case OP_CRPLUS:
case OP_CRMINPLUS:
case OP_CRQUERY:
case OP_CRMINQUERY:
c = *ecode++ - OP_CRSTAR;
minimize = (c & 1) != 0;
min = rep_min[c]; /* Pick up values from tables; */
max = rep_max[c]; /* zero for max => infinity */
if (max == 0) max = INT_MAX;
break;
case OP_CRRANGE:
case OP_CRMINRANGE:
minimize = (*ecode == OP_CRMINRANGE);
min = GET2(ecode, 1);
max = GET2(ecode, 1 + IMM2_SIZE);
if (max == 0) max = INT_MAX;
ecode += 1 + 2 * IMM2_SIZE;
break;
default: /* No repeat follows */
{
int rc = match_ref(offset, offset_top, eptr, mb, caseless, &length);
if (rc != 0)
{
if (rc > 0) eptr = mb->end_subject; /* Partial match */
CHECK_PARTIAL();
RRETURN(MATCH_NOMATCH);
}
}
eptr += length;
continue; /* With the main loop */
}
/* Handle repeated back references. If a set group has length zero, just
continue with the main loop, because it matches however many times. For an
unset reference, if the minimum is zero, we can also just continue. We an
also continue if PCRE2_MATCH_UNSET_BACKREF is set, because this makes unset
group be have as a zero-length group. For any other unset cases, carrying
on will result in NOMATCH. */
if (offset < offset_top && mb->ovector[offset] != PCRE2_UNSET)
{
if (mb->ovector[offset] == mb->ovector[offset + 1]) continue;
}
else /* Group is not set */
{
if (min == 0 ||