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Modules/sre_lib.h
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Miss Islington (bot)
bpo-39943: Fix MSVC warnings in sre extension (GH-20508)
14 мар 2021, 15:17
Не верифицирован
14 мар 2021, 15:17
cf8d6ef
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/* * Secret Labs' Regular Expression Engine * * regular expression matching engine * * Copyright (c) 1997-2001 by Secret Labs AB. All rights reserved. * * See the _sre.c file for information on usage and redistribution. */ /* String matching engine */ /* This file is included three times, with different character settings */ LOCAL(int) SRE(at)(SRE_STATE* state, const SRE_CHAR* ptr, SRE_CODE at) { /* check if pointer is at given position */ Py_ssize_t thisp, thatp; 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 (((SRE_CHAR *)state->end - ptr == 1 && 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; thatp = ((void*) ptr > state->beginning) ? SRE_IS_WORD((int) ptr[-1]) : 0; thisp = ((void*) ptr < state->end) ? SRE_IS_WORD((int) ptr[0]) : 0; return thisp != thatp; case SRE_AT_NON_BOUNDARY: if (state->beginning == state->end) return 0; thatp = ((void*) ptr > state->beginning) ? SRE_IS_WORD((int) ptr[-1]) : 0; thisp = ((void*) ptr < state->end) ? SRE_IS_WORD((int) ptr[0]) : 0; return thisp == thatp; case SRE_AT_LOC_BOUNDARY: if (state->beginning == state->end) return 0; thatp = ((void*) ptr > state->beginning) ? SRE_LOC_IS_WORD((int) ptr[-1]) : 0; thisp = ((void*) ptr < state->end) ? SRE_LOC_IS_WORD((int) ptr[0]) : 0; return thisp != thatp; case SRE_AT_LOC_NON_BOUNDARY: if (state->beginning == state->end) return 0; thatp = ((void*) ptr > state->beginning) ? SRE_LOC_IS_WORD((int) ptr[-1]) : 0; thisp = ((void*) ptr < state->end) ? SRE_LOC_IS_WORD((int) ptr[0]) : 0; return thisp == thatp; case SRE_AT_UNI_BOUNDARY: if (state->beginning == state->end) return 0; thatp = ((void*) ptr > state->beginning) ? SRE_UNI_IS_WORD((int) ptr[-1]) : 0; thisp = ((void*) ptr < state->end) ? SRE_UNI_IS_WORD((int) ptr[0]) : 0; return thisp != thatp; case SRE_AT_UNI_NON_BOUNDARY: if (state->beginning == state->end) return 0; thatp = ((void*) ptr > state->beginning) ? SRE_UNI_IS_WORD((int) ptr[-1]) : 0; thisp = ((void*) ptr < state->end) ? SRE_UNI_IS_WORD((int) ptr[0]) : 0; return thisp == thatp; } return 0; } LOCAL(int) SRE(charset)(SRE_STATE* state, const 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++; break; case SRE_OP_CHARSET: /* <CHARSET> <bitmap> */ if (ch < 256 && (set[ch/SRE_CODE_BITS] & (1u << (ch & (SRE_CODE_BITS-1))))) return ok; set += 256/SRE_CODE_BITS; break; case SRE_OP_RANGE: /* <RANGE> <lower> <upper> */ if (set[0] <= ch && ch <= set[1]) return ok; set += 2; break; case SRE_OP_RANGE_UNI_IGNORE: /* <RANGE_UNI_IGNORE> <lower> <upper> */ { SRE_CODE uch; /* ch is already lower cased */ if (set[0] <= ch && ch <= set[1]) return ok; uch = sre_upper_unicode(ch); if (set[0] <= uch && uch <= set[1]) return ok; set += 2; break; } case SRE_OP_NEGATE: ok = !ok; break; case SRE_OP_BIGCHARSET: /* <BIGCHARSET> <blockcount> <256 blockindices> <blocks> */ { Py_ssize_t count, block; count = *(set++); if (ch < 0x10000u) block = ((unsigned char*)set)[ch >> 8]; else block = -1; set += 256/sizeof(SRE_CODE); if (block >=0 && (set[(block * 256 + (ch & 255))/SRE_CODE_BITS] & (1u << (ch & (SRE_CODE_BITS-1))))) return ok; set += count * (256/SRE_CODE_BITS); 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(charset_loc_ignore)(SRE_STATE* state, const SRE_CODE* set, SRE_CODE ch) { SRE_CODE lo, up; lo = sre_lower_locale(ch); if (SRE(charset)(state, set, lo)) return 1; up = sre_upper_locale(ch); return up != lo && SRE(charset)(state, set, up); } LOCAL(Py_ssize_t) SRE(match)(SRE_STATE* state, const SRE_CODE* pattern, int toplevel); LOCAL(Py_ssize_t) SRE(count)(SRE_STATE* state, const SRE_CODE* pattern, Py_ssize_t maxcount) { SRE_CODE chr; SRE_CHAR c; const SRE_CHAR* ptr = (const SRE_CHAR *)state->ptr; const SRE_CHAR* end = (const SRE_CHAR *)state->end; Py_ssize_t i; /* adjust end */ if (maxcount < end - ptr && maxcount != SRE_MAXREPEAT) 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)(state, 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)); c = (SRE_CHAR) chr; #if SIZEOF_SRE_CHAR < 4 if ((SRE_CODE) c != chr) ; /* literal can't match: doesn't fit in char width */ else #endif while (ptr < end && *ptr == c) 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) sre_lower_ascii(*ptr) == chr) ptr++; break; case SRE_OP_LITERAL_UNI_IGNORE: /* repeated literal */ chr = pattern[1]; TRACE(("|%p|%p|COUNT LITERAL_UNI_IGNORE %d\n", pattern, ptr, chr)); while (ptr < end && (SRE_CODE) sre_lower_unicode(*ptr) == chr) ptr++; break; case SRE_OP_LITERAL_LOC_IGNORE: /* repeated literal */ chr = pattern[1]; TRACE(("|%p|%p|COUNT LITERAL_LOC_IGNORE %d\n", pattern, ptr, chr)); while (ptr < end && char_loc_ignore(chr, *ptr)) ptr++; break; case SRE_OP_NOT_LITERAL: /* repeated non-literal */ chr = pattern[1]; TRACE(("|%p|%p|COUNT NOT_LITERAL %d\n", pattern, ptr, chr)); c = (SRE_CHAR) chr; #if SIZEOF_SRE_CHAR < 4 if ((SRE_CODE) c != chr) ptr = end; /* literal can't match: doesn't fit in char width */ else #endif while (ptr < end && *ptr != c) 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) sre_lower_ascii(*ptr) != chr) ptr++; break; case SRE_OP_NOT_LITERAL_UNI_IGNORE: /* repeated non-literal */ chr = pattern[1]; TRACE(("|%p|%p|COUNT NOT_LITERAL_UNI_IGNORE %d\n", pattern, ptr, chr)); while (ptr < end && (SRE_CODE) sre_lower_unicode(*ptr) != chr) ptr++; break; case SRE_OP_NOT_LITERAL_LOC_IGNORE: /* repeated non-literal */ chr = pattern[1]; TRACE(("|%p|%p|COUNT NOT_LITERAL_LOC_IGNORE %d\n", pattern, ptr, chr)); while (ptr < end && !char_loc_ignore(chr, *ptr)) 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, 0); if (i < 0) return i; if (!i) break; } TRACE(("|%p|%p|COUNT %" PY_FORMAT_SIZE_T "d\n", pattern, ptr, (SRE_CHAR*) state->ptr - ptr)); return (SRE_CHAR*) state->ptr - ptr; } TRACE(("|%p|%p|COUNT %" PY_FORMAT_SIZE_T "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, const 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 */ const SRE_CHAR* end = (const SRE_CHAR*) state->end; const SRE_CHAR* ptr = (const SRE_CHAR*) state->ptr; Py_ssize_t 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 DATA_STACK_ALLOC(state, type, ptr) \ do { \ alloc_pos = state->data_stack_base; \ TRACE(("allocating %s in %" PY_FORMAT_SIZE_T "d " \ "(%" PY_FORMAT_SIZE_T "d)\n", \ Py_STRINGIFY(type), alloc_pos, sizeof(type))); \ if (sizeof(type) > state->data_stack_size - alloc_pos) { \ 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 %" PY_FORMAT_SIZE_T "d\n", Py_STRINGIFY(type), pos)); \ ptr = (type*)(state->data_stack+pos); \ } while (0) #define DATA_STACK_PUSH(state, data, size) \ do { \ TRACE(("copy data in %p to %" PY_FORMAT_SIZE_T "d " \ "(%" PY_FORMAT_SIZE_T "d)\n", \ data, state->data_stack_base, size)); \ if (size > state->data_stack_size - state->data_stack_base) { \ 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) /* We add an explicit cast to memcpy here because MSVC has a bug when compiling C code where it believes that `const void**` cannot be safely casted to `void*`, see bpo-39943 for details. */ #define DATA_STACK_POP(state, data, size, discard) \ do { \ TRACE(("copy data to %p from %" PY_FORMAT_SIZE_T "d " \ "(%" PY_FORMAT_SIZE_T "d)\n", \ data, state->data_stack_base-size, size)); \ memcpy((void*) 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 %" PY_FORMAT_SIZE_T "d " \ "(%" PY_FORMAT_SIZE_T "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_JUMPX(jumpvalue, jumplabel, nextpattern, toplevel_) \ DATA_ALLOC(SRE(match_context), nextctx); \ nextctx->last_ctx_pos = ctx_pos; \ nextctx->jump = jumpvalue; \ nextctx->pattern = nextpattern; \ nextctx->toplevel = toplevel_; \ ctx_pos = alloc_pos; \ ctx = nextctx; \ goto entrance; \ jumplabel: \ while (0) /* gcc doesn't like labels at end of scopes */ \ #define DO_JUMP(jumpvalue, jumplabel, nextpattern) \ DO_JUMPX(jumpvalue, jumplabel, nextpattern, ctx->toplevel) #define DO_JUMP0(jumpvalue, jumplabel, nextpattern) \ DO_JUMPX(jumpvalue, jumplabel, nextpattern, 0) typedef struct { Py_ssize_t last_ctx_pos; Py_ssize_t jump; const SRE_CHAR* ptr; const SRE_CODE* pattern; Py_ssize_t count; Py_ssize_t lastmark; Py_ssize_t lastindex; union { SRE_CODE chr; SRE_REPEAT* rep; } u; int toplevel; } SRE(match_context); /* check if string matches the given pattern. returns <0 for error, 0 for failure, and 1 for success */ LOCAL(Py_ssize_t) SRE(match)(SRE_STATE* state, const SRE_CODE* pattern, int toplevel) { const SRE_CHAR* end = (const SRE_CHAR *)state->end; Py_ssize_t alloc_pos, ctx_pos = -1; Py_ssize_t i, ret = 0; Py_ssize_t jump; unsigned int sigcount=0; 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->toplevel = toplevel; ctx_pos = alloc_pos; entrance: ctx->ptr = (SRE_CHAR *)state->ptr; if (ctx->pattern[0] == SRE_OP_INFO) { /* optimization info block */ /* <INFO> <1=skip> <2=flags> <3=min> ... */ if (ctx->pattern[3] && (uintptr_t)(end - ctx->ptr) < ctx->pattern[3]) { TRACE(("reject (got %" PY_FORMAT_SIZE_T "d chars, " "need %" PY_FORMAT_SIZE_T "d)\n", end - ctx->ptr, (Py_ssize_t) ctx->pattern[3])); RETURN_FAILURE; } ctx->pattern += ctx->pattern[1] + 1; } for (;;) { ++sigcount; if ((0 == (sigcount & 0xfff)) && PyErr_CheckSignals()) RETURN_ERROR(SRE_ERROR_INTERRUPTED); 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. */ Py_ssize_t 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)); if (ctx->toplevel && ((state->match_all && ctx->ptr != state->end) || (state->must_advance && ctx->ptr == state->start))) { RETURN_FAILURE; } 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)(state, 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 || sre_lower_ascii(*ctx->ptr) != *ctx->pattern) RETURN_FAILURE; ctx->pattern++; ctx->ptr++; break; case SRE_OP_LITERAL_UNI_IGNORE: TRACE(("|%p|%p|LITERAL_UNI_IGNORE %d\n", ctx->pattern, ctx->ptr, ctx->pattern[0])); if (ctx->ptr >= end || sre_lower_unicode(*ctx->ptr) != *ctx->pattern) RETURN_FAILURE; ctx->pattern++; ctx->ptr++; break; case SRE_OP_LITERAL_LOC_IGNORE: TRACE(("|%p|%p|LITERAL_LOC_IGNORE %d\n", ctx->pattern, ctx->ptr, ctx->pattern[0])); if (ctx->ptr >= end || !char_loc_ignore(*ctx->pattern, *ctx->ptr)) 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 || sre_lower_ascii(*ctx->ptr) == *ctx->pattern) RETURN_FAILURE; ctx->pattern++; ctx->ptr++; break; case SRE_OP_NOT_LITERAL_UNI_IGNORE: TRACE(("|%p|%p|NOT_LITERAL_UNI_IGNORE %d\n", ctx->pattern, ctx->ptr, *ctx->pattern)); if (ctx->ptr >= end || sre_lower_unicode(*ctx->ptr) == *ctx->pattern) RETURN_FAILURE; ctx->pattern++; ctx->ptr++; break; case SRE_OP_NOT_LITERAL_LOC_IGNORE: TRACE(("|%p|%p|NOT_LITERAL_LOC_IGNORE %d\n", ctx->pattern, ctx->ptr, *ctx->pattern)); if (ctx->ptr >= end || char_loc_ignore(*ctx->pattern, *ctx->ptr)) 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)(state, ctx->pattern+1, (SRE_CODE)sre_lower_ascii(*ctx->ptr))) RETURN_FAILURE; ctx->pattern += ctx->pattern[0]; ctx->ptr++; break; case SRE_OP_IN_UNI_IGNORE: TRACE(("|%p|%p|IN_UNI_IGNORE\n", ctx->pattern, ctx->ptr)); if (ctx->ptr >= end || !SRE(charset)(state, ctx->pattern+1, (SRE_CODE)sre_lower_unicode(*ctx->ptr))) RETURN_FAILURE; ctx->pattern += ctx->pattern[0]; ctx->ptr++; break; case SRE_OP_IN_LOC_IGNORE: TRACE(("|%p|%p|IN_LOC_IGNORE\n", ctx->pattern, ctx->ptr)); if (ctx->ptr >= end || !SRE(charset_loc_ignore)(state, ctx->pattern+1, *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)(state, 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; } if (ctx->u.rep) MARK_POP_KEEP(ctx->lastmark); LASTMARK_RESTORE(); } if (ctx->u.rep) MARK_POP_DISCARD(ctx->lastmark); RETURN_FAILURE; case SRE_OP_REPEAT_ONE: /* match repeated sequence (maximizing regexp) */ /* this operator only works if the repeated item is exactly one character wide, and we're not already collecting backtracking points. for other cases, use the MAX_REPEAT operator */ /* <REPEAT_ONE> <skip> <1=min> <2=max> item <SUCCESS> tail */ TRACE(("|%p|%p|REPEAT_ONE %d %d\n", ctx->pattern, ctx->ptr, ctx->pattern[1], ctx->pattern[2])); if ((Py_ssize_t) ctx->pattern[1] > end - ctx->ptr) RETURN_FAILURE; /* cannot match */ state->ptr = ctx->ptr; ret = SRE(count)(state, ctx->pattern+3, ctx->pattern[2]); RETURN_ON_ERROR(ret); DATA_LOOKUP_AT(SRE(match_context), ctx, ctx_pos); ctx->count = ret; ctx->ptr += ctx->count; /* when we arrive here, count contains the number of matches, and ctx->ptr points to the tail of the target string. check if the rest of the pattern matches, and backtrack if not. */ if (ctx->count < (Py_ssize_t) ctx->pattern[1]) RETURN_FAILURE; if (ctx->pattern[ctx->pattern[0]] == SRE_OP_SUCCESS && ctx->ptr == state->end && !(ctx->toplevel && state->must_advance && ctx->ptr == state->start)) { /* tail is empty. we're finished */ state->ptr = ctx->ptr; RETURN_SUCCESS; } LASTMARK_SAVE(); if (ctx->pattern[ctx->pattern[0]] == SRE_OP_LITERAL) { /* tail starts with a literal. skip positions where the rest of the pattern cannot possibly match */ ctx->u.chr = ctx->pattern[ctx->pattern[0]+1]; for (;;) { while (ctx->count >= (Py_ssize_t) ctx->pattern[1] && (ctx->ptr >= end || *ctx->ptr != ctx->u.chr)) { ctx->ptr--; ctx->count--; } if (ctx->count < (Py_ssize_t) ctx->pattern[1]) break; state->ptr = ctx->ptr; DO_JUMP(JUMP_REPEAT_ONE_1, jump_repeat_one_1, ctx->pattern+ctx->pattern[0]); if (ret) { RETURN_ON_ERROR(ret); RETURN_SUCCESS; } LASTMARK_RESTORE(); ctx->ptr--; ctx->count--; } } else { /* general case */ while (ctx->count >= (Py_ssize_t) ctx->pattern[1]) { state->ptr = ctx->ptr; DO_JUMP(JUMP_REPEAT_ONE_2, jump_repeat_one_2, ctx->pattern+ctx->pattern[0]); if (ret) { RETURN_ON_ERROR(ret); RETURN_SUCCESS; } ctx->ptr--; ctx->count--; LASTMARK_RESTORE(); } } RETURN_FAILURE; case SRE_OP_MIN_REPEAT_ONE: /* match repeated sequence (minimizing regexp) */ /* this operator only works if the repeated item is exactly one character wide, and we're not already collecting backtracking points. for other cases, use the MIN_REPEAT operator */ /* <MIN_REPEAT_ONE> <skip> <1=min> <2=max> item <SUCCESS> tail */ TRACE(("|%p|%p|MIN_REPEAT_ONE %d %d\n", ctx->pattern, ctx->ptr, ctx->pattern[1], ctx->pattern[2])); if ((Py_ssize_t) ctx->pattern[1] > end - ctx->ptr) RETURN_FAILURE; /* cannot match */ state->ptr = ctx->ptr; if (ctx->pattern[1] == 0) ctx->count = 0; else { /* count using pattern min as the maximum */ ret = SRE(count)(state, ctx->pattern+3, ctx->pattern[1]); RETURN_ON_ERROR(ret); DATA_LOOKUP_AT(SRE(match_context), ctx, ctx_pos); if (ret < (Py_ssize_t) ctx->pattern[1]) /* didn't match minimum number of times */ RETURN_FAILURE; /* advance past minimum matches of repeat */ ctx->count = ret; ctx->ptr += ctx->count; } if (ctx->pattern[ctx->pattern[0]] == SRE_OP_SUCCESS && !(ctx->toplevel && ((state->match_all && ctx->ptr != state->end) || (state->must_advance && ctx->ptr == state->start)))) { /* tail is empty. we're finished */ state->ptr = ctx->ptr; RETURN_SUCCESS; } else { /* general case */ LASTMARK_SAVE(); while ((Py_ssize_t)ctx->pattern[2] == SRE_MAXREPEAT || ctx->count <= (Py_ssize_t)ctx->pattern[2]) { state->ptr = ctx->ptr; DO_JUMP(JUMP_MIN_REPEAT_ONE,jump_min_repeat_one, ctx->pattern+ctx->pattern[0]); if (ret) { RETURN_ON_ERROR(ret); RETURN_SUCCESS; } state->ptr = ctx->ptr; ret = SRE(count)(state, ctx->pattern+3, 1); RETURN_ON_ERROR(ret); DATA_LOOKUP_AT(SRE(match_context), ctx, ctx_pos); if (ret == 0) break; assert(ret == 1); ctx->ptr++; ctx->count++; LASTMARK_RESTORE(); } } RETURN_FAILURE; case SRE_OP_REPEAT: /* create repeat context. all the hard work is done by the UNTIL operator (MAX_UNTIL, MIN_UNTIL) */ /* <REPEAT> <skip> <1=min> <2=max> item <UNTIL> tail */ TRACE(("|%p|%p|REPEAT %d %d\n", ctx->pattern, ctx->ptr, ctx->pattern[1], ctx->pattern[2])); /* install new repeat context */ ctx->u.rep = (SRE_REPEAT*) PyObject_MALLOC(sizeof(*ctx->u.rep)); if (!ctx->u.rep) { PyErr_NoMemory(); RETURN_FAILURE; } ctx->u.rep->count = -1; ctx->u.rep->pattern = ctx->pattern; ctx->u.rep->prev = state->repeat; ctx->u.rep->last_ptr = NULL; state->repeat = ctx->u.rep; state->ptr = ctx->ptr; DO_JUMP(JUMP_REPEAT, jump_repeat, ctx->pattern+ctx->pattern[0]); state->repeat = ctx->u.rep->prev; PyObject_FREE(ctx->u.rep); if (ret) { RETURN_ON_ERROR(ret); RETURN_SUCCESS; } RETURN_FAILURE; case SRE_OP_MAX_UNTIL: /* maximizing repeat */ /* <REPEAT> <skip> <1=min> <2=max> item <MAX_UNTIL> tail */ /* FIXME: we probably need to deal with zero-width matches in here... */ ctx->u.rep = state->repeat; if (!ctx->u.rep) RETURN_ERROR(SRE_ERROR_STATE); state->ptr = ctx->ptr; ctx->count = ctx->u.rep->count+1; TRACE(("|%p|%p|MAX_UNTIL %" PY_FORMAT_SIZE_T "d\n", ctx->pattern, ctx->ptr, ctx->count)); if (ctx->count < (Py_ssize_t) ctx->u.rep->pattern[1]) { /* not enough matches */ ctx->u.rep->count = ctx->count; DO_JUMP(JUMP_MAX_UNTIL_1, jump_max_until_1, ctx->u.rep->pattern+3); if (ret) { RETURN_ON_ERROR(ret); RETURN_SUCCESS; } ctx->u.rep->count = ctx->count-1; state->ptr = ctx->ptr; RETURN_FAILURE; } if ((ctx->count < (Py_ssize_t) ctx->u.rep->pattern[2] || ctx->u.rep->pattern[2] == SRE_MAXREPEAT) && state->ptr != ctx->u.rep->last_ptr) { /* we may have enough matches, but if we can match another item, do so */ ctx->u.rep->count = ctx->count; LASTMARK_SAVE(); MARK_PUSH(ctx->lastmark); /* zero-width match protection */ DATA_PUSH(&ctx->u.rep->last_ptr); ctx->u.rep->last_ptr = state->ptr; DO_JUMP(JUMP_MAX_UNTIL_2, jump_max_until_2, ctx->u.rep->pattern+3); DATA_POP(&ctx->u.rep->last_ptr); if (ret) { MARK_POP_DISCARD(ctx->lastmark); RETURN_ON_ERROR(ret); RETURN_SUCCESS; } MARK_POP(ctx->lastmark); LASTMARK_RESTORE(); ctx->u.rep->count = ctx->count-1; state->ptr = ctx->ptr; } /* cannot match more repeated items here. make sure the tail matches */ state->repeat = ctx->u.rep->prev; DO_JUMP(JUMP_MAX_UNTIL_3, jump_max_until_3, ctx->pattern); RETURN_ON_SUCCESS(ret); state->repeat = ctx->u.rep; state->ptr = ctx->ptr; RETURN_FAILURE; case SRE_OP_MIN_UNTIL: /* minimizing repeat */ /* <REPEAT> <skip> <1=min> <2=max> item <MIN_UNTIL> tail */ ctx->u.rep = state->repeat; if (!ctx->u.rep) RETURN_ERROR(SRE_ERROR_STATE); state->ptr = ctx->ptr; ctx->count = ctx->u.rep->count+1; TRACE(("|%p|%p|MIN_UNTIL %" PY_FORMAT_SIZE_T "d %p\n", ctx->pattern, ctx->ptr, ctx->count, ctx->u.rep->pattern)); if (ctx->count < (Py_ssize_t) ctx->u.rep->pattern[1]) { /* not enough matches */ ctx->u.rep->count = ctx->count; DO_JUMP(JUMP_MIN_UNTIL_1, jump_min_until_1, ctx->u.rep->pattern+3); if (ret) { RETURN_ON_ERROR(ret); RETURN_SUCCESS; } ctx->u.rep->count = ctx->count-1; state->ptr = ctx->ptr; RETURN_FAILURE; } LASTMARK_SAVE(); /* see if the tail matches */ state->repeat = ctx->u.rep->prev; DO_JUMP(JUMP_MIN_UNTIL_2, jump_min_until_2, ctx->pattern); if (ret) { RETURN_ON_ERROR(ret); RETURN_SUCCESS; } state->repeat = ctx->u.rep; state->ptr = ctx->ptr; LASTMARK_RESTORE(); if ((ctx->count >= (Py_ssize_t) ctx->u.rep->pattern[2] && ctx->u.rep->pattern[2] != SRE_MAXREPEAT) || state->ptr == ctx->u.rep->last_ptr) RETURN_FAILURE; ctx->u.rep->count = ctx->count; /* zero-width match protection */ DATA_PUSH(&ctx->u.rep->last_ptr); ctx->u.rep->last_ptr = state->ptr; DO_JUMP(JUMP_MIN_UNTIL_3,jump_min_until_3, ctx->u.rep->pattern+3); DATA_POP(&ctx->u.rep->last_ptr); if (ret) { RETURN_ON_ERROR(ret); RETURN_SUCCESS; } ctx->u.rep->count = ctx->count-1; state->ptr = ctx->ptr; RETURN_FAILURE; case SRE_OP_GROUPREF: /* match backreference */ TRACE(("|%p|%p|GROUPREF %d\n", ctx->pattern, ctx->ptr, ctx->pattern[0])); i = ctx->pattern[0]; { Py_ssize_t groupref = i+i; if (groupref >= state->lastmark) { RETURN_FAILURE; } else { SRE_CHAR* p = (SRE_CHAR*) state->mark[groupref]; SRE_CHAR* e = (SRE_CHAR*) state->mark[groupref+1]; if (!p || !e || e < p) RETURN_FAILURE; while (p < e) { if (ctx->ptr >= end || *ctx->ptr != *p) RETURN_FAILURE; p++; ctx->ptr++; } } } ctx->pattern++; break; case SRE_OP_GROUPREF_IGNORE: /* match backreference */ TRACE(("|%p|%p|GROUPREF_IGNORE %d\n", ctx->pattern, ctx->ptr, ctx->pattern[0])); i = ctx->pattern[0]; { Py_ssize_t groupref = i+i; if (groupref >= state->lastmark) { RETURN_FAILURE; } else { SRE_CHAR* p = (SRE_CHAR*) state->mark[groupref]; SRE_CHAR* e = (SRE_CHAR*) state->mark[groupref+1]; if (!p || !e || e < p) RETURN_FAILURE; while (p < e) { if (ctx->ptr >= end || sre_lower_ascii(*ctx->ptr) != sre_lower_ascii(*p)) RETURN_FAILURE; p++; ctx->ptr++; } } } ctx->pattern++; break; case SRE_OP_GROUPREF_UNI_IGNORE: /* match backreference */ TRACE(("|%p|%p|GROUPREF_UNI_IGNORE %d\n", ctx->pattern, ctx->ptr, ctx->pattern[0])); i = ctx->pattern[0]; { Py_ssize_t groupref = i+i; if (groupref >= state->lastmark) { RETURN_FAILURE; } else { SRE_CHAR* p = (SRE_CHAR*) state->mark[groupref]; SRE_CHAR* e = (SRE_CHAR*) state->mark[groupref+1]; if (!p || !e || e < p) RETURN_FAILURE; while (p < e) { if (ctx->ptr >= end || sre_lower_unicode(*ctx->ptr) != sre_lower_unicode(*p)) RETURN_FAILURE; p++; ctx->ptr++; } } } ctx->pattern++; break; case SRE_OP_GROUPREF_LOC_IGNORE: /* match backreference */ TRACE(("|%p|%p|GROUPREF_LOC_IGNORE %d\n", ctx->pattern, ctx->ptr, ctx->pattern[0])); i = ctx->pattern[0]; { Py_ssize_t groupref = i+i; if (groupref >= state->lastmark) { RETURN_FAILURE; } else { SRE_CHAR* p = (SRE_CHAR*) state->mark[groupref]; SRE_CHAR* e = (SRE_CHAR*) state->mark[groupref+1]; if (!p || !e || e < p) RETURN_FAILURE; while (p < e) { if (ctx->ptr >= end || sre_lower_locale(*ctx->ptr) != sre_lower_locale(*p)) RETURN_FAILURE; p++; ctx->ptr++; } } } ctx->pattern++; break; case SRE_OP_GROUPREF_EXISTS: TRACE(("|%p|%p|GROUPREF_EXISTS %d\n", ctx->pattern, ctx->ptr, ctx->pattern[0])); /* <GROUPREF_EXISTS> <group> <skip> codeyes <JUMP> codeno ... */ i = ctx->pattern[0]; { Py_ssize_t groupref = i+i; if (groupref >= state->lastmark) { ctx->pattern += ctx->pattern[1]; break; } else { SRE_CHAR* p = (SRE_CHAR*) state->mark[groupref]; SRE_CHAR* e = (SRE_CHAR*) state->mark[groupref+1]; if (!p || !e || e < p) { ctx->pattern += ctx->pattern[1]; break; } } } ctx->pattern += 2; break; case SRE_OP_ASSERT: /* assert subpattern */ /* <ASSERT> <skip> <back> <pattern> */ TRACE(("|%p|%p|ASSERT %d\n", ctx->pattern, ctx->ptr, ctx->pattern[1])); if (ctx->ptr - (SRE_CHAR *)state->beginning < (Py_ssize_t)ctx->pattern[1]) RETURN_FAILURE; state->ptr = ctx->ptr - ctx->pattern[1]; DO_JUMP0(JUMP_ASSERT, jump_assert, ctx->pattern+2); RETURN_ON_FAILURE(ret); ctx->pattern += ctx->pattern[0]; break; case SRE_OP_ASSERT_NOT: /* assert not subpattern */ /* <ASSERT_NOT> <skip> <back> <pattern> */ TRACE(("|%p|%p|ASSERT_NOT %d\n", ctx->pattern, ctx->ptr, ctx->pattern[1])); if (ctx->ptr - (SRE_CHAR *)state->beginning >= (Py_ssize_t)ctx->pattern[1]) { state->ptr = ctx->ptr - ctx->pattern[1]; DO_JUMP0(JUMP_ASSERT_NOT, jump_assert_not, ctx->pattern+2); if (ret) { RETURN_ON_ERROR(ret); RETURN_FAILURE; } } ctx->pattern += ctx->pattern[0]; break; case SRE_OP_FAILURE: /* immediate failure */ TRACE(("|%p|%p|FAILURE\n", ctx->pattern, ctx->ptr)); RETURN_FAILURE; default: TRACE(("|%p|%p|UNKNOWN %d\n", ctx->pattern, ctx->ptr, ctx->pattern[-1])); RETURN_ERROR(SRE_ERROR_ILLEGAL); } } exit: ctx_pos = ctx->last_ctx_pos; jump = ctx->jump; DATA_POP_DISCARD(ctx); if (ctx_pos == -1) return ret; DATA_LOOKUP_AT(SRE(match_context), ctx, ctx_pos); switch (jump) { case JUMP_MAX_UNTIL_2: TRACE(("|%p|%p|JUMP_MAX_UNTIL_2\n", ctx->pattern, ctx->ptr)); goto jump_max_until_2; case JUMP_MAX_UNTIL_3: TRACE(("|%p|%p|JUMP_MAX_UNTIL_3\n", ctx->pattern, ctx->ptr)); goto jump_max_until_3; case JUMP_MIN_UNTIL_2: TRACE(("|%p|%p|JUMP_MIN_UNTIL_2\n", ctx->pattern, ctx->ptr)); goto jump_min_until_2; case JUMP_MIN_UNTIL_3: TRACE(("|%p|%p|JUMP_MIN_UNTIL_3\n", ctx->pattern, ctx->ptr)); goto jump_min_until_3; case JUMP_BRANCH: TRACE(("|%p|%p|JUMP_BRANCH\n", ctx->pattern, ctx->ptr)); goto jump_branch; case JUMP_MAX_UNTIL_1: TRACE(("|%p|%p|JUMP_MAX_UNTIL_1\n", ctx->pattern, ctx->ptr)); goto jump_max_until_1; case JUMP_MIN_UNTIL_1: TRACE(("|%p|%p|JUMP_MIN_UNTIL_1\n", ctx->pattern, ctx->ptr)); goto jump_min_until_1; case JUMP_REPEAT: TRACE(("|%p|%p|JUMP_REPEAT\n", ctx->pattern, ctx->ptr)); goto jump_repeat; case JUMP_REPEAT_ONE_1: TRACE(("|%p|%p|JUMP_REPEAT_ONE_1\n", ctx->pattern, ctx->ptr)); goto jump_repeat_one_1; case JUMP_REPEAT_ONE_2: TRACE(("|%p|%p|JUMP_REPEAT_ONE_2\n", ctx->pattern, ctx->ptr)); goto jump_repeat_one_2; case JUMP_MIN_REPEAT_ONE: TRACE(("|%p|%p|JUMP_MIN_REPEAT_ONE\n", ctx->pattern, ctx->ptr)); goto jump_min_repeat_one; case JUMP_ASSERT: TRACE(("|%p|%p|JUMP_ASSERT\n", ctx->pattern, ctx->ptr)); goto jump_assert; case JUMP_ASSERT_NOT: TRACE(("|%p|%p|JUMP_ASSERT_NOT\n", ctx->pattern, ctx->ptr)); goto jump_assert_not; case JUMP_NONE: TRACE(("|%p|%p|RETURN %" PY_FORMAT_SIZE_T "d\n", ctx->pattern, ctx->ptr, ret)); break; } return ret; /* should never get here */ } /* need to reset capturing groups between two SRE(match) callings in loops */ #define RESET_CAPTURE_GROUP() \ do { state->lastmark = state->lastindex = -1; } while (0) LOCAL(Py_ssize_t) SRE(search)(SRE_STATE* state, SRE_CODE* pattern) { SRE_CHAR* ptr = (SRE_CHAR *)state->start; SRE_CHAR* end = (SRE_CHAR *)state->end; Py_ssize_t status = 0; Py_ssize_t prefix_len = 0; Py_ssize_t prefix_skip = 0; SRE_CODE* prefix = NULL; SRE_CODE* charset = NULL; SRE_CODE* overlap = NULL; int flags = 0; if (ptr > end) return 0; if (pattern[0] == SRE_OP_INFO) { /* optimization info block */ /* <INFO> <1=skip> <2=flags> <3=min> <4=max> <5=prefix info> */ flags = pattern[2]; if (pattern[3] && end - ptr < (Py_ssize_t)pattern[3]) { TRACE(("reject (got %u chars, need %u)\n", (unsigned int)(end - ptr), pattern[3])); return 0; } if (pattern[3] > 1) { /* adjust end point (but make sure we leave at least one character in there, so literal search will work) */ end -= pattern[3] - 1; if (end <= ptr) end = ptr; } if (flags & SRE_INFO_PREFIX) { /* pattern starts with a known prefix */ /* <length> <skip> <prefix data> <overlap data> */ prefix_len = pattern[5]; prefix_skip = pattern[6]; prefix = pattern + 7; overlap = prefix + prefix_len - 1; } else if (flags & SRE_INFO_CHARSET) /* pattern starts with a character from a known set */ /* <charset> */ charset = pattern + 5; pattern += 1 + pattern[1]; } TRACE(("prefix = %p %" PY_FORMAT_SIZE_T "d %" PY_FORMAT_SIZE_T "d\n", prefix, prefix_len, prefix_skip)); TRACE(("charset = %p\n", charset)); if (prefix_len == 1) { /* pattern starts with a literal character */ SRE_CHAR c = (SRE_CHAR) prefix[0]; #if SIZEOF_SRE_CHAR < 4 if ((SRE_CODE) c != prefix[0]) return 0; /* literal can't match: doesn't fit in char width */ #endif end = (SRE_CHAR *)state->end; state->must_advance = 0; while (ptr < end) { while (*ptr != c) { if (++ptr >= end) return 0; } TRACE(("|%p|%p|SEARCH LITERAL\n", pattern, ptr)); state->start = ptr; state->ptr = ptr + prefix_skip; if (flags & SRE_INFO_LITERAL) return 1; /* we got all of it */ status = SRE(match)(state, pattern + 2*prefix_skip, 0); if (status != 0) return status; ++ptr; RESET_CAPTURE_GROUP(); } return 0; } if (prefix_len > 1) { /* pattern starts with a known prefix. use the overlap table to skip forward as fast as we possibly can */ Py_ssize_t i = 0; end = (SRE_CHAR *)state->end; if (prefix_len > end - ptr) return 0; #if SIZEOF_SRE_CHAR < 4 for (i = 0; i < prefix_len; i++) if ((SRE_CODE)(SRE_CHAR) prefix[i] != prefix[i]) return 0; /* literal can't match: doesn't fit in char width */ #endif while (ptr < end) { SRE_CHAR c = (SRE_CHAR) prefix[0]; while (*ptr++ != c) { if (ptr >= end) return 0; } if (ptr >= end) return 0; i = 1; state->must_advance = 0; do { if (*ptr == (SRE_CHAR) prefix[i]) { if (++i != prefix_len) { if (++ptr >= end) return 0; continue; } /* found a potential match */ TRACE(("|%p|%p|SEARCH SCAN\n", pattern, ptr)); state->start = ptr - (prefix_len - 1); state->ptr = ptr - (prefix_len - prefix_skip - 1); if (flags & SRE_INFO_LITERAL) return 1; /* we got all of it */ status = SRE(match)(state, pattern + 2*prefix_skip, 0); if (status != 0) return status; /* close but no cigar -- try again */ if (++ptr >= end) return 0; RESET_CAPTURE_GROUP(); } i = overlap[i]; } while (i != 0); } return 0; } if (charset) { /* pattern starts with a character from a known set */ end = (SRE_CHAR *)state->end; state->must_advance = 0; for (;;) { while (ptr < end && !SRE(charset)(state, charset, *ptr)) ptr++; if (ptr >= end) return 0; TRACE(("|%p|%p|SEARCH CHARSET\n", pattern, ptr)); state->start = ptr; state->ptr = ptr; status = SRE(match)(state, pattern, 0); if (status != 0) break; ptr++; RESET_CAPTURE_GROUP(); } } else { /* general case */ assert(ptr <= end); TRACE(("|%p|%p|SEARCH\n", pattern, ptr)); state->start = state->ptr = ptr; status = SRE(match)(state, pattern, 1); state->must_advance = 0; while (status == 0 && ptr < end) { ptr++; RESET_CAPTURE_GROUP(); TRACE(("|%p|%p|SEARCH\n", pattern, ptr)); state->start = state->ptr = ptr; status = SRE(match)(state, pattern, 0); } } return status; } #undef SRE_CHAR #undef SIZEOF_SRE_CHAR #undef SRE /* vim:ts=4:sw=4:et */