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_sre.c
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_sre.c
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/*
* Secret Labs' Regular Expression Engine
*
* regular expression matching engine
*
* partial history:
* 1999-10-24 fl created (based on existing template matcher code)
* 2000-03-06 fl first alpha, sort of
* 2000-08-01 fl fixes for 1.6b1
* 2000-08-07 fl use PyOS_CheckStack() if available
* 2000-09-20 fl added expand method
* 2001-03-20 fl lots of fixes for 2.1b2
* 2001-04-15 fl export copyright as Python attribute, not global
* 2001-04-28 fl added __copy__ methods (work in progress)
* 2001-05-14 fl fixes for 1.5.2 compatibility
* 2001-07-01 fl added BIGCHARSET support (from Martin von Loewis)
* 2001-10-18 fl fixed group reset issue (from Matthew Mueller)
* 2001-10-20 fl added split primitive; reenable unicode for 1.6/2.0/2.1
* 2001-10-21 fl added sub/subn primitive
* 2001-10-24 fl added finditer primitive (for 2.2 only)
* 2001-12-07 fl fixed memory leak in sub/subn (Guido van Rossum)
* 2002-11-09 fl fixed empty sub/subn return type
* 2003-04-18 mvl fully support 4-byte codes
* 2003-10-17 gn implemented non recursive scheme
*
* Copyright (c) 1997-2001 by Secret Labs AB. All rights reserved.
*
* This version of the SRE library can be redistributed under CNRI's
* Python 1.6 license. For any other use, please contact Secret Labs
* AB ([email protected]).
*
* Portions of this engine have been developed in cooperation with
* CNRI. Hewlett-Packard provided funding for 1.6 integration and
* other compatibility work.
*/
#ifndef SRE_RECURSIVE
static char copyright[] =
" SRE 2.2.2 Copyright (c) 1997-2002 by Secret Labs AB ";
#include "Python.h"
#include "structmember.h" /* offsetof */
#include "sre.h"
#include <ctype.h>
/* name of this module, minus the leading underscore */
#if !defined(SRE_MODULE)
#define SRE_MODULE "sre"
#endif
/* defining this one enables tracing */
#undef VERBOSE
#if PY_VERSION_HEX >= 0x01060000
#if PY_VERSION_HEX < 0x02020000 || defined(Py_USING_UNICODE)
/* defining this enables unicode support (default under 1.6a1 and later) */
#define HAVE_UNICODE
#endif
#endif
/* -------------------------------------------------------------------- */
/* optional features */
/* enables fast searching */
#define USE_FAST_SEARCH
/* enables aggressive inlining (always on for Visual C) */
#undef USE_INLINE
/* enables copy/deepcopy handling (work in progress) */
#undef USE_BUILTIN_COPY
#if PY_VERSION_HEX < 0x01060000
#define PyObject_DEL(op) PyMem_DEL((op))
#endif
/* -------------------------------------------------------------------- */
#if defined(_MSC_VER)
#pragma optimize("agtw", on) /* doesn't seem to make much difference... */
#pragma warning(disable: 4710) /* who cares if functions are not inlined ;-) */
/* fastest possible local call under MSVC */
#define LOCAL(type) static __inline type __fastcall
#elif defined(USE_INLINE)
#define LOCAL(type) static inline type
#else
#define LOCAL(type) static type
#endif
/* error codes */
#define SRE_ERROR_ILLEGAL -1 /* illegal opcode */
#define SRE_ERROR_STATE -2 /* illegal state */
#define SRE_ERROR_RECURSION_LIMIT -3 /* runaway recursion */
#define SRE_ERROR_MEMORY -9 /* out of memory */
#if defined(VERBOSE)
#define TRACE(v) printf v
#else
#define TRACE(v)
#endif
/* -------------------------------------------------------------------- */
/* search engine state */
/* default character predicates (run sre_chars.py to regenerate tables) */
#define SRE_DIGIT_MASK 1
#define SRE_SPACE_MASK 2
#define SRE_LINEBREAK_MASK 4
#define SRE_ALNUM_MASK 8
#define SRE_WORD_MASK 16
/* FIXME: this assumes ASCII. create tables in init_sre() instead */
static char sre_char_info[128] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 6, 2,
2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 25, 25, 25, 25, 25, 25, 25, 25,
25, 25, 0, 0, 0, 0, 0, 0, 0, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 0, 0,
0, 0, 16, 0, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 0, 0, 0, 0, 0 };
static char sre_char_lower[128] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,
27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,
44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60,
61, 62, 63, 64, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,
108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,
122, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105,
106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,
120, 121, 122, 123, 124, 125, 126, 127 };
#define SRE_IS_DIGIT(ch)\
((ch) < 128 ? (sre_char_info[(ch)] & SRE_DIGIT_MASK) : 0)
#define SRE_IS_SPACE(ch)\
((ch) < 128 ? (sre_char_info[(ch)] & SRE_SPACE_MASK) : 0)
#define SRE_IS_LINEBREAK(ch)\
((ch) < 128 ? (sre_char_info[(ch)] & SRE_LINEBREAK_MASK) : 0)
#define SRE_IS_ALNUM(ch)\
((ch) < 128 ? (sre_char_info[(ch)] & SRE_ALNUM_MASK) : 0)
#define SRE_IS_WORD(ch)\
((ch) < 128 ? (sre_char_info[(ch)] & SRE_WORD_MASK) : 0)
static unsigned int sre_lower(unsigned int ch)
{
return ((ch) < 128 ? (unsigned int)sre_char_lower[ch] : ch);
}
/* locale-specific character predicates */
/* !(c & ~N) == (c < N+1) for any unsigned c, this avoids
* warnings when c's type supports only numbers < N+1 */
#define SRE_LOC_IS_DIGIT(ch) (!((ch) & ~255) ? isdigit((ch)) : 0)
#define SRE_LOC_IS_SPACE(ch) (!((ch) & ~255) ? isspace((ch)) : 0)
#define SRE_LOC_IS_LINEBREAK(ch) ((ch) == '\n')
#define SRE_LOC_IS_ALNUM(ch) (!((ch) & ~255) ? isalnum((ch)) : 0)
#define SRE_LOC_IS_WORD(ch) (SRE_LOC_IS_ALNUM((ch)) || (ch) == '_')
static unsigned int sre_lower_locale(unsigned int ch)
{
return ((ch) < 256 ? (unsigned int)tolower((ch)) : ch);
}
/* unicode-specific character predicates */
#if defined(HAVE_UNICODE)
#define SRE_UNI_IS_DIGIT(ch) Py_UNICODE_ISDIGIT((Py_UNICODE)(ch))
#define SRE_UNI_IS_SPACE(ch) Py_UNICODE_ISSPACE((Py_UNICODE)(ch))
#define SRE_UNI_IS_LINEBREAK(ch) Py_UNICODE_ISLINEBREAK((Py_UNICODE)(ch))
#define SRE_UNI_IS_ALNUM(ch) Py_UNICODE_ISALNUM((Py_UNICODE)(ch))
#define SRE_UNI_IS_WORD(ch) (SRE_UNI_IS_ALNUM((ch)) || (ch) == '_')
static unsigned int sre_lower_unicode(unsigned int ch)
{
return (unsigned int) Py_UNICODE_TOLOWER((Py_UNICODE)(ch));
}
#endif
LOCAL(int)
sre_category(SRE_CODE category, unsigned int ch)
{
switch (category) {
case SRE_CATEGORY_DIGIT:
return SRE_IS_DIGIT(ch);
case SRE_CATEGORY_NOT_DIGIT:
return !SRE_IS_DIGIT(ch);
case SRE_CATEGORY_SPACE:
return SRE_IS_SPACE(ch);
case SRE_CATEGORY_NOT_SPACE:
return !SRE_IS_SPACE(ch);
case SRE_CATEGORY_WORD:
return SRE_IS_WORD(ch);
case SRE_CATEGORY_NOT_WORD:
return !SRE_IS_WORD(ch);
case SRE_CATEGORY_LINEBREAK:
return SRE_IS_LINEBREAK(ch);
case SRE_CATEGORY_NOT_LINEBREAK:
return !SRE_IS_LINEBREAK(ch);
case SRE_CATEGORY_LOC_WORD:
return SRE_LOC_IS_WORD(ch);
case SRE_CATEGORY_LOC_NOT_WORD:
return !SRE_LOC_IS_WORD(ch);
#if defined(HAVE_UNICODE)
case SRE_CATEGORY_UNI_DIGIT:
return SRE_UNI_IS_DIGIT(ch);
case SRE_CATEGORY_UNI_NOT_DIGIT:
return !SRE_UNI_IS_DIGIT(ch);
case SRE_CATEGORY_UNI_SPACE:
return SRE_UNI_IS_SPACE(ch);
case SRE_CATEGORY_UNI_NOT_SPACE:
return !SRE_UNI_IS_SPACE(ch);
case SRE_CATEGORY_UNI_WORD:
return SRE_UNI_IS_WORD(ch);
case SRE_CATEGORY_UNI_NOT_WORD:
return !SRE_UNI_IS_WORD(ch);
case SRE_CATEGORY_UNI_LINEBREAK:
return SRE_UNI_IS_LINEBREAK(ch);
case SRE_CATEGORY_UNI_NOT_LINEBREAK:
return !SRE_UNI_IS_LINEBREAK(ch);
#else
case SRE_CATEGORY_UNI_DIGIT:
return SRE_IS_DIGIT(ch);
case SRE_CATEGORY_UNI_NOT_DIGIT:
return !SRE_IS_DIGIT(ch);
case SRE_CATEGORY_UNI_SPACE:
return SRE_IS_SPACE(ch);
case SRE_CATEGORY_UNI_NOT_SPACE:
return !SRE_IS_SPACE(ch);
case SRE_CATEGORY_UNI_WORD:
return SRE_LOC_IS_WORD(ch);
case SRE_CATEGORY_UNI_NOT_WORD:
return !SRE_LOC_IS_WORD(ch);
case SRE_CATEGORY_UNI_LINEBREAK:
return SRE_IS_LINEBREAK(ch);
case SRE_CATEGORY_UNI_NOT_LINEBREAK:
return !SRE_IS_LINEBREAK(ch);
#endif
}
return 0;
}
/* helpers */
static void
data_stack_dealloc(SRE_STATE* state)
{
if (state->data_stack) {
free(state->data_stack);
state->data_stack = NULL;
}
state->data_stack_size = state->data_stack_base = 0;
}
static int
data_stack_grow(SRE_STATE* state, int size)
{
int minsize, cursize;
minsize = state->data_stack_base+size;
cursize = state->data_stack_size;
if (cursize < minsize) {
void* stack;
cursize = minsize+minsize/4+1024;
TRACE(("allocate/grow stack %d\n", cursize));
stack = realloc(state->data_stack, cursize);
if (!stack) {
data_stack_dealloc(state);
return SRE_ERROR_MEMORY;
}
state->data_stack = stack;
state->data_stack_size = cursize;
}
return 0;
}
/* generate 8-bit version */
#define SRE_CHAR unsigned char
#define SRE_AT sre_at
#define SRE_COUNT sre_count
#define SRE_CHARSET sre_charset
#define SRE_INFO sre_info
#define SRE_MATCH sre_match
#define SRE_MATCH_CONTEXT sre_match_context
#define SRE_SEARCH sre_search
#define SRE_LITERAL_TEMPLATE sre_literal_template
#if defined(HAVE_UNICODE)
#define SRE_RECURSIVE
#include "_sre.c"
#undef SRE_RECURSIVE
#undef SRE_LITERAL_TEMPLATE
#undef SRE_SEARCH
#undef SRE_MATCH
#undef SRE_MATCH_CONTEXT
#undef SRE_INFO
#undef SRE_CHARSET
#undef SRE_COUNT
#undef SRE_AT
#undef SRE_CHAR
/* generate 16-bit unicode version */
#define SRE_CHAR Py_UNICODE
#define SRE_AT sre_uat
#define SRE_COUNT sre_ucount
#define SRE_CHARSET sre_ucharset
#define SRE_INFO sre_uinfo
#define SRE_MATCH sre_umatch
#define SRE_MATCH_CONTEXT sre_umatch_context
#define SRE_SEARCH sre_usearch
#define SRE_LITERAL_TEMPLATE sre_uliteral_template
#endif
#endif /* SRE_RECURSIVE */
/* -------------------------------------------------------------------- */
/* String matching engine */
/* the following section is compiled twice, with different character
settings */
LOCAL(int)
SRE_AT(SRE_STATE* state, SRE_CHAR* ptr, SRE_CODE at)
{
/* check if pointer is at given position */
int this, that;
switch (at) {
case SRE_AT_BEGINNING:
case SRE_AT_BEGINNING_STRING:
return ((void*) ptr == state->beginning);
case SRE_AT_BEGINNING_LINE:
return ((void*) ptr == state->beginning ||
SRE_IS_LINEBREAK((int) ptr[-1]));
case SRE_AT_END:
return (((void*) (ptr+1) == state->end &&
SRE_IS_LINEBREAK((int) ptr[0])) ||
((void*) ptr == state->end));
case SRE_AT_END_LINE:
return ((void*) ptr == state->end ||
SRE_IS_LINEBREAK((int) ptr[0]));
case SRE_AT_END_STRING:
return ((void*) ptr == state->end);
case SRE_AT_BOUNDARY:
if (state->beginning == state->end)
return 0;
that = ((void*) ptr > state->beginning) ?
SRE_IS_WORD((int) ptr[-1]) : 0;
this = ((void*) ptr < state->end) ?
SRE_IS_WORD((int) ptr[0]) : 0;
return this != that;
case SRE_AT_NON_BOUNDARY:
if (state->beginning == state->end)
return 0;
that = ((void*) ptr > state->beginning) ?
SRE_IS_WORD((int) ptr[-1]) : 0;
this = ((void*) ptr < state->end) ?
SRE_IS_WORD((int) ptr[0]) : 0;
return this == that;
case SRE_AT_LOC_BOUNDARY:
if (state->beginning == state->end)
return 0;
that = ((void*) ptr > state->beginning) ?
SRE_LOC_IS_WORD((int) ptr[-1]) : 0;
this = ((void*) ptr < state->end) ?
SRE_LOC_IS_WORD((int) ptr[0]) : 0;
return this != that;
case SRE_AT_LOC_NON_BOUNDARY:
if (state->beginning == state->end)
return 0;
that = ((void*) ptr > state->beginning) ?
SRE_LOC_IS_WORD((int) ptr[-1]) : 0;
this = ((void*) ptr < state->end) ?
SRE_LOC_IS_WORD((int) ptr[0]) : 0;
return this == that;
#if defined(HAVE_UNICODE)
case SRE_AT_UNI_BOUNDARY:
if (state->beginning == state->end)
return 0;
that = ((void*) ptr > state->beginning) ?
SRE_UNI_IS_WORD((int) ptr[-1]) : 0;
this = ((void*) ptr < state->end) ?
SRE_UNI_IS_WORD((int) ptr[0]) : 0;
return this != that;
case SRE_AT_UNI_NON_BOUNDARY:
if (state->beginning == state->end)
return 0;
that = ((void*) ptr > state->beginning) ?
SRE_UNI_IS_WORD((int) ptr[-1]) : 0;
this = ((void*) ptr < state->end) ?
SRE_UNI_IS_WORD((int) ptr[0]) : 0;
return this == that;
#endif
}
return 0;
}
LOCAL(int)
SRE_CHARSET(SRE_CODE* set, SRE_CODE ch)
{
/* check if character is a member of the given set */
int ok = 1;
for (;;) {
switch (*set++) {
case SRE_OP_FAILURE:
return !ok;
case SRE_OP_LITERAL:
/* <LITERAL> <code> */
if (ch == set[0])
return ok;
set++;
break;
case SRE_OP_CATEGORY:
/* <CATEGORY> <code> */
if (sre_category(set[0], (int) ch))
return ok;
set += 1;
break;
case SRE_OP_CHARSET:
if (sizeof(SRE_CODE) == 2) {
/* <CHARSET> <bitmap> (16 bits per code word) */
if (ch < 256 && (set[ch >> 4] & (1 << (ch & 15))))
return ok;
set += 16;
}
else {
/* <CHARSET> <bitmap> (32 bits per code word) */
if (ch < 256 && (set[ch >> 5] & (1 << (ch & 31))))
return ok;
set += 8;
}
break;
case SRE_OP_RANGE:
/* <RANGE> <lower> <upper> */
if (set[0] <= ch && ch <= set[1])
return ok;
set += 2;
break;
case SRE_OP_NEGATE:
ok = !ok;
break;
case SRE_OP_BIGCHARSET:
/* <BIGCHARSET> <blockcount> <256 blockindices> <blocks> */
{
int count, block;
count = *(set++);
if (sizeof(SRE_CODE) == 2) {
block = ((unsigned char*)set)[ch >> 8];
set += 128;
if (set[block*16 + ((ch & 255)>>4)] & (1 << (ch & 15)))
return ok;
set += count*16;
}
else {
/* !(c & ~N) == (c < N+1) for any unsigned c, this avoids
* warnings when c's type supports only numbers < N+1 */
if (!(ch & ~65535))
block = ((unsigned char*)set)[ch >> 8];
else
block = -1;
set += 64;
if (block >=0 &&
(set[block*8 + ((ch & 255)>>5)] & (1 << (ch & 31))))
return ok;
set += count*8;
}
break;
}
default:
/* internal error -- there's not much we can do about it
here, so let's just pretend it didn't match... */
return 0;
}
}
}
LOCAL(int) SRE_MATCH(SRE_STATE* state, SRE_CODE* pattern);
LOCAL(int)
SRE_COUNT(SRE_STATE* state, SRE_CODE* pattern, int maxcount)
{
SRE_CODE chr;
SRE_CHAR* ptr = state->ptr;
SRE_CHAR* end = state->end;
int i;
/* adjust end */
if (maxcount < end - ptr && maxcount != 65535)
end = ptr + maxcount;
switch (pattern[0]) {
case SRE_OP_IN:
/* repeated set */
TRACE(("|%p|%p|COUNT IN\n", pattern, ptr));
while (ptr < end && SRE_CHARSET(pattern + 2, *ptr))
ptr++;
break;
case SRE_OP_ANY:
/* repeated dot wildcard. */
TRACE(("|%p|%p|COUNT ANY\n", pattern, ptr));
while (ptr < end && !SRE_IS_LINEBREAK(*ptr))
ptr++;
break;
case SRE_OP_ANY_ALL:
/* repeated dot wildcard. skip to the end of the target
string, and backtrack from there */
TRACE(("|%p|%p|COUNT ANY_ALL\n", pattern, ptr));
ptr = end;
break;
case SRE_OP_LITERAL:
/* repeated literal */
chr = pattern[1];
TRACE(("|%p|%p|COUNT LITERAL %d\n", pattern, ptr, chr));
while (ptr < end && (SRE_CODE) *ptr == chr)
ptr++;
break;
case SRE_OP_LITERAL_IGNORE:
/* repeated literal */
chr = pattern[1];
TRACE(("|%p|%p|COUNT LITERAL_IGNORE %d\n", pattern, ptr, chr));
while (ptr < end && (SRE_CODE) state->lower(*ptr) == chr)
ptr++;
break;
case SRE_OP_NOT_LITERAL:
/* repeated non-literal */
chr = pattern[1];
TRACE(("|%p|%p|COUNT NOT_LITERAL %d\n", pattern, ptr, chr));
while (ptr < end && (SRE_CODE) *ptr != chr)
ptr++;
break;
case SRE_OP_NOT_LITERAL_IGNORE:
/* repeated non-literal */
chr = pattern[1];
TRACE(("|%p|%p|COUNT NOT_LITERAL_IGNORE %d\n", pattern, ptr, chr));
while (ptr < end && (SRE_CODE) state->lower(*ptr) != chr)
ptr++;
break;
default:
/* repeated single character pattern */
TRACE(("|%p|%p|COUNT SUBPATTERN\n", pattern, ptr));
while ((SRE_CHAR*) state->ptr < end) {
i = SRE_MATCH(state, pattern);
if (i < 0)
return i;
if (!i)
break;
}
TRACE(("|%p|%p|COUNT %d\n", pattern, ptr,
(SRE_CHAR*) state->ptr - ptr));
return (SRE_CHAR*) state->ptr - ptr;
}
TRACE(("|%p|%p|COUNT %d\n", pattern, ptr, ptr - (SRE_CHAR*) state->ptr));
return ptr - (SRE_CHAR*) state->ptr;
}
#if 0 /* not used in this release */
LOCAL(int)
SRE_INFO(SRE_STATE* state, SRE_CODE* pattern)
{
/* check if an SRE_OP_INFO block matches at the current position.
returns the number of SRE_CODE objects to skip if successful, 0
if no match */
SRE_CHAR* end = state->end;
SRE_CHAR* ptr = state->ptr;
int i;
/* check minimal length */
if (pattern[3] && (end - ptr) < pattern[3])
return 0;
/* check known prefix */
if (pattern[2] & SRE_INFO_PREFIX && pattern[5] > 1) {
/* <length> <skip> <prefix data> <overlap data> */
for (i = 0; i < pattern[5]; i++)
if ((SRE_CODE) ptr[i] != pattern[7 + i])
return 0;
return pattern[0] + 2 * pattern[6];
}
return pattern[0];
}
#endif
/* The macros below should be used to protect recursive SRE_MATCH()
* calls that *failed* and do *not* return immediately (IOW, those
* that will backtrack). Explaining:
*
* - Recursive SRE_MATCH() returned true: that's usually a success
* (besides atypical cases like ASSERT_NOT), therefore there's no
* reason to restore lastmark;
*
* - Recursive SRE_MATCH() returned false but the current SRE_MATCH()
* is returning to the caller: If the current SRE_MATCH() is the
* top function of the recursion, returning false will be a matching
* failure, and it doesn't matter where lastmark is pointing to.
* If it's *not* the top function, it will be a recursive SRE_MATCH()
* failure by itself, and the calling SRE_MATCH() will have to deal
* with the failure by the same rules explained here (it will restore
* lastmark by itself if necessary);
*
* - Recursive SRE_MATCH() returned false, and will continue the
* outside 'for' loop: must be protected when breaking, since the next
* OP could potentially depend on lastmark;
*
* - Recursive SRE_MATCH() returned false, and will be called again
* inside a local for/while loop: must be protected between each
* loop iteration, since the recursive SRE_MATCH() could do anything,
* and could potentially depend on lastmark.
*
* For more information, check the discussion at SF patch #712900.
*/
#define LASTMARK_SAVE() \
do { \
ctx->lastmark = state->lastmark; \
ctx->lastindex = state->lastindex; \
} while (0)
#define LASTMARK_RESTORE() \
do { \
state->lastmark = ctx->lastmark; \
state->lastindex = ctx->lastindex; \
} while (0)
#define RETURN_ERROR(i) do { return i; } while(0)
#define RETURN_FAILURE do { ret = 0; goto exit; } while(0)
#define RETURN_SUCCESS do { ret = 1; goto exit; } while(0)
#define RETURN_ON_ERROR(i) \
do { if (i < 0) RETURN_ERROR(i); } while (0)
#define RETURN_ON_SUCCESS(i) \
do { RETURN_ON_ERROR(i); if (i > 0) RETURN_SUCCESS; } while (0)
#define RETURN_ON_FAILURE(i) \
do { RETURN_ON_ERROR(i); if (i == 0) RETURN_FAILURE; } while (0)
#define SFY(x) #x
#define DATA_STACK_ALLOC(state, type, ptr) \
do { \
alloc_pos = state->data_stack_base; \
TRACE(("allocating %s in %d (%d)\n", \
SFY(type), alloc_pos, sizeof(type))); \
if (state->data_stack_size < alloc_pos+sizeof(type)) { \
int j = data_stack_grow(state, sizeof(type)); \
if (j < 0) return j; \
if (ctx_pos != -1) \
DATA_STACK_LOOKUP_AT(state, SRE_MATCH_CONTEXT, ctx, ctx_pos); \
} \
ptr = (type*)(state->data_stack+alloc_pos); \
state->data_stack_base += sizeof(type); \
} while (0)
#define DATA_STACK_LOOKUP_AT(state, type, ptr, pos) \
do { \
TRACE(("looking up %s at %d\n", SFY(type), pos)); \
ptr = (type*)(state->data_stack+pos); \
} while (0)
#define DATA_STACK_PUSH(state, data, size) \
do { \
TRACE(("copy data in %p to %d (%d)\n", \
data, state->data_stack_base, size)); \
if (state->data_stack_size < state->data_stack_base+size) { \
int j = data_stack_grow(state, size); \
if (j < 0) return j; \
if (ctx_pos != -1) \
DATA_STACK_LOOKUP_AT(state, SRE_MATCH_CONTEXT, ctx, ctx_pos); \
} \
memcpy(state->data_stack+state->data_stack_base, data, size); \
state->data_stack_base += size; \
} while (0)
#define DATA_STACK_POP(state, data, size, discard) \
do { \
TRACE(("copy data to %p from %d (%d)\n", \
data, state->data_stack_base-size, size)); \
memcpy(data, state->data_stack+state->data_stack_base-size, size); \
if (discard) \
state->data_stack_base -= size; \
} while (0)
#define DATA_STACK_POP_DISCARD(state, size) \
do { \
TRACE(("discard data from %d (%d)\n", \
state->data_stack_base-size, size)); \
state->data_stack_base -= size; \
} while(0)
#define DATA_PUSH(x) \
DATA_STACK_PUSH(state, (x), sizeof(*(x)))
#define DATA_POP(x) \
DATA_STACK_POP(state, (x), sizeof(*(x)), 1)
#define DATA_POP_DISCARD(x) \
DATA_STACK_POP_DISCARD(state, sizeof(*(x)))
#define DATA_ALLOC(t,p) \
DATA_STACK_ALLOC(state, t, p)
#define DATA_LOOKUP_AT(t,p,pos) \
DATA_STACK_LOOKUP_AT(state,t,p,pos)
#define MARK_PUSH(lastmark) \
do if (lastmark > 0) { \
i = lastmark; /* ctx->lastmark may change if reallocated */ \
DATA_STACK_PUSH(state, state->mark, (i+1)*sizeof(void*)); \
} while (0)
#define MARK_POP(lastmark) \
do if (lastmark > 0) { \
DATA_STACK_POP(state, state->mark, (lastmark+1)*sizeof(void*), 1); \
} while (0)
#define MARK_POP_KEEP(lastmark) \
do if (lastmark > 0) { \
DATA_STACK_POP(state, state->mark, (lastmark+1)*sizeof(void*), 0); \
} while (0)
#define MARK_POP_DISCARD(lastmark) \
do if (lastmark > 0) { \
DATA_STACK_POP_DISCARD(state, (lastmark+1)*sizeof(void*)); \
} while (0)
#define JUMP_NONE 0
#define JUMP_MAX_UNTIL_1 1
#define JUMP_MAX_UNTIL_2 2
#define JUMP_MAX_UNTIL_3 3
#define JUMP_MIN_UNTIL_1 4
#define JUMP_MIN_UNTIL_2 5
#define JUMP_MIN_UNTIL_3 6
#define JUMP_REPEAT 7
#define JUMP_REPEAT_ONE_1 8
#define JUMP_REPEAT_ONE_2 9
#define JUMP_MIN_REPEAT_ONE 10
#define JUMP_BRANCH 11
#define JUMP_ASSERT 12
#define JUMP_ASSERT_NOT 13
#define DO_JUMP(jumpvalue, jumplabel, nextpattern) \
DATA_ALLOC(SRE_MATCH_CONTEXT, nextctx); \
nextctx->last_ctx_pos = ctx_pos; \
nextctx->jump = jumpvalue; \
nextctx->pattern = nextpattern; \
ctx_pos = alloc_pos; \
ctx = nextctx; \
goto entrance; \
jumplabel: \
while (0) /* gcc doesn't like labels at end of scopes */ \
typedef struct {
int last_ctx_pos;
int jump;
SRE_CHAR* ptr;
SRE_CODE* pattern;
int count;
int lastmark;
int lastindex;
union {
SRE_CODE chr;
SRE_REPEAT* rep;
} u;
} SRE_MATCH_CONTEXT;
/* check if string matches the given pattern. returns <0 for
error, 0 for failure, and 1 for success */
LOCAL(int)
SRE_MATCH(SRE_STATE* state, SRE_CODE* pattern)
{
SRE_CHAR* end = state->end;
int alloc_pos, ctx_pos = -1;
int i, ret = 0;
int jump;
SRE_MATCH_CONTEXT* ctx;
SRE_MATCH_CONTEXT* nextctx;
TRACE(("|%p|%p|ENTER\n", pattern, state->ptr));
DATA_ALLOC(SRE_MATCH_CONTEXT, ctx);
ctx->last_ctx_pos = -1;
ctx->jump = JUMP_NONE;
ctx->pattern = pattern;
ctx_pos = alloc_pos;
entrance:
ctx->ptr = state->ptr;
if (ctx->pattern[0] == SRE_OP_INFO) {
/* optimization info block */
/* <INFO> <1=skip> <2=flags> <3=min> ... */
if (ctx->pattern[3] && (end - ctx->ptr) < ctx->pattern[3]) {
TRACE(("reject (got %d chars, need %d)\n",
(end - ctx->ptr), ctx->pattern[3]));
RETURN_FAILURE;
}
ctx->pattern += ctx->pattern[1] + 1;
}
for (;;) {
switch (*ctx->pattern++) {
case SRE_OP_MARK:
/* set mark */
/* <MARK> <gid> */
TRACE(("|%p|%p|MARK %d\n", ctx->pattern,
ctx->ptr, ctx->pattern[0]));
i = ctx->pattern[0];
if (i & 1)
state->lastindex = i/2 + 1;
if (i > state->lastmark) {
/* state->lastmark is the highest valid index in the
state->mark array. If it is increased by more than 1,
the intervening marks must be set to NULL to signal
that these marks have not been encountered. */
int j = state->lastmark + 1;
while (j < i)
state->mark[j++] = NULL;
state->lastmark = i;
}
state->mark[i] = ctx->ptr;
ctx->pattern++;
break;
case SRE_OP_LITERAL:
/* match literal string */
/* <LITERAL> <code> */
TRACE(("|%p|%p|LITERAL %d\n", ctx->pattern,
ctx->ptr, *ctx->pattern));
if (ctx->ptr >= end || (SRE_CODE) ctx->ptr[0] != ctx->pattern[0])
RETURN_FAILURE;
ctx->pattern++;
ctx->ptr++;
break;
case SRE_OP_NOT_LITERAL:
/* match anything that is not literal character */
/* <NOT_LITERAL> <code> */
TRACE(("|%p|%p|NOT_LITERAL %d\n", ctx->pattern,
ctx->ptr, *ctx->pattern));
if (ctx->ptr >= end || (SRE_CODE) ctx->ptr[0] == ctx->pattern[0])
RETURN_FAILURE;
ctx->pattern++;
ctx->ptr++;
break;
case SRE_OP_SUCCESS:
/* end of pattern */
TRACE(("|%p|%p|SUCCESS\n", ctx->pattern, ctx->ptr));
state->ptr = ctx->ptr;
RETURN_SUCCESS;
case SRE_OP_AT:
/* match at given position */
/* <AT> <code> */
TRACE(("|%p|%p|AT %d\n", ctx->pattern, ctx->ptr, *ctx->pattern));
if (!SRE_AT(state, ctx->ptr, *ctx->pattern))
RETURN_FAILURE;
ctx->pattern++;
break;
case SRE_OP_CATEGORY:
/* match at given category */
/* <CATEGORY> <code> */
TRACE(("|%p|%p|CATEGORY %d\n", ctx->pattern,
ctx->ptr, *ctx->pattern));
if (ctx->ptr >= end || !sre_category(ctx->pattern[0], ctx->ptr[0]))
RETURN_FAILURE;
ctx->pattern++;
ctx->ptr++;
break;
case SRE_OP_ANY:
/* match anything (except a newline) */
/* <ANY> */
TRACE(("|%p|%p|ANY\n", ctx->pattern, ctx->ptr));
if (ctx->ptr >= end || SRE_IS_LINEBREAK(ctx->ptr[0]))
RETURN_FAILURE;
ctx->ptr++;
break;
case SRE_OP_ANY_ALL:
/* match anything */
/* <ANY_ALL> */
TRACE(("|%p|%p|ANY_ALL\n", ctx->pattern, ctx->ptr));
if (ctx->ptr >= end)
RETURN_FAILURE;
ctx->ptr++;
break;
case SRE_OP_IN:
/* match set member (or non_member) */
/* <IN> <skip> <set> */
TRACE(("|%p|%p|IN\n", ctx->pattern, ctx->ptr));
if (ctx->ptr >= end || !SRE_CHARSET(ctx->pattern + 1, *ctx->ptr))
RETURN_FAILURE;
ctx->pattern += ctx->pattern[0];
ctx->ptr++;
break;
case SRE_OP_LITERAL_IGNORE:
TRACE(("|%p|%p|LITERAL_IGNORE %d\n",
ctx->pattern, ctx->ptr, ctx->pattern[0]));
if (ctx->ptr >= end ||
state->lower(*ctx->ptr) != state->lower(*ctx->pattern))
RETURN_FAILURE;
ctx->pattern++;
ctx->ptr++;
break;
case SRE_OP_NOT_LITERAL_IGNORE:
TRACE(("|%p|%p|NOT_LITERAL_IGNORE %d\n",
ctx->pattern, ctx->ptr, *ctx->pattern));
if (ctx->ptr >= end ||
state->lower(*ctx->ptr) == state->lower(*ctx->pattern))
RETURN_FAILURE;
ctx->pattern++;
ctx->ptr++;
break;
case SRE_OP_IN_IGNORE:
TRACE(("|%p|%p|IN_IGNORE\n", ctx->pattern, ctx->ptr));
if (ctx->ptr >= end
|| !SRE_CHARSET(ctx->pattern+1,
(SRE_CODE)state->lower(*ctx->ptr)))
RETURN_FAILURE;
ctx->pattern += ctx->pattern[0];
ctx->ptr++;
break;
case SRE_OP_JUMP:
case SRE_OP_INFO:
/* jump forward */
/* <JUMP> <offset> */
TRACE(("|%p|%p|JUMP %d\n", ctx->pattern,
ctx->ptr, ctx->pattern[0]));
ctx->pattern += ctx->pattern[0];
break;
case SRE_OP_BRANCH:
/* alternation */
/* <BRANCH> <0=skip> code <JUMP> ... <NULL> */
TRACE(("|%p|%p|BRANCH\n", ctx->pattern, ctx->ptr));
LASTMARK_SAVE();
ctx->u.rep = state->repeat;
if (ctx->u.rep)
MARK_PUSH(ctx->lastmark);
for (; ctx->pattern[0]; ctx->pattern += ctx->pattern[0]) {
if (ctx->pattern[1] == SRE_OP_LITERAL &&
(ctx->ptr >= end ||
(SRE_CODE) *ctx->ptr != ctx->pattern[2]))
continue;
if (ctx->pattern[1] == SRE_OP_IN &&
(ctx->ptr >= end ||
!SRE_CHARSET(ctx->pattern + 3, (SRE_CODE) *ctx->ptr)))
continue;
state->ptr = ctx->ptr;
DO_JUMP(JUMP_BRANCH, jump_branch, ctx->pattern+1);
if (ret) {
if (ctx->u.rep)
MARK_POP_DISCARD(ctx->lastmark);
RETURN_ON_ERROR(ret);
RETURN_SUCCESS;
}