diff options
Diffstat (limited to 'regexec.c')
| -rw-r--r-- | regexec.c | 3983 |
1 files changed, 3983 insertions, 0 deletions
diff --git a/regexec.c b/regexec.c new file mode 100644 index 00000000..841218e7 --- /dev/null +++ b/regexec.c @@ -0,0 +1,3983 @@ +/* Extended regular expression matching and search library. + Copyright (C) 2002, 2003 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +static reg_errcode_t match_ctx_init _RE_ARGS((re_match_context_t *cache, int eflags, + re_string_t *input, int n)); +static void match_ctx_clean _RE_ARGS((re_match_context_t *mctx)); +static void match_ctx_free _RE_ARGS((re_match_context_t *cache)); +static void match_ctx_free_subtops _RE_ARGS((re_match_context_t *mctx)); +static reg_errcode_t match_ctx_add_entry _RE_ARGS((re_match_context_t *cache, int node, + int str_idx, int from, int to)); +static int search_cur_bkref_entry _RE_ARGS((re_match_context_t *mctx, int str_idx)); +static void match_ctx_clear_flag _RE_ARGS((re_match_context_t *mctx)); +static reg_errcode_t match_ctx_add_subtop _RE_ARGS((re_match_context_t *mctx, int node, + int str_idx)); +static re_sub_match_last_t * match_ctx_add_sublast _RE_ARGS((re_sub_match_top_t *subtop, + int node, int str_idx)); +static void sift_ctx_init _RE_ARGS((re_sift_context_t *sctx, re_dfastate_t **sifted_sts, + re_dfastate_t **limited_sts, int last_node, + int last_str_idx, int check_subexp)); +static reg_errcode_t re_search_internal _RE_ARGS((const regex_t *preg, + const char *string, int length, + int start, int range, int stop, + size_t nmatch, regmatch_t pmatch[], + int eflags)); +static int re_search_2_stub _RE_ARGS((struct re_pattern_buffer *bufp, + const char *string1, int length1, + const char *string2, int length2, + int start, int range, struct re_registers *regs, + int stop, int ret_len)); +static int re_search_stub _RE_ARGS((struct re_pattern_buffer *bufp, + const char *string, int length, int start, + int range, int stop, struct re_registers *regs, + int ret_len)); +static unsigned re_copy_regs _RE_ARGS((struct re_registers *regs, regmatch_t *pmatch, + int nregs, int regs_allocated)); +static inline re_dfastate_t *acquire_init_state_context _RE_ARGS((reg_errcode_t *err, + const regex_t *preg, + const re_match_context_t *mctx, + int idx)); +static reg_errcode_t prune_impossible_nodes _RE_ARGS((const regex_t *preg, + re_match_context_t *mctx)); +static int check_matching _RE_ARGS((const regex_t *preg, re_match_context_t *mctx, + int fl_search, int fl_longest_match)); +static int check_halt_node_context _RE_ARGS((const re_dfa_t *dfa, int node, + unsigned int context)); +static int check_halt_state_context _RE_ARGS((const regex_t *preg, + const re_dfastate_t *state, + const re_match_context_t *mctx, int idx)); +static void update_regs _RE_ARGS((re_dfa_t *dfa, regmatch_t *pmatch, int cur_node, + int cur_idx, int nmatch)); +static int proceed_next_node _RE_ARGS((const regex_t *preg, int nregs, regmatch_t *regs, + const re_match_context_t *mctx, + int *pidx, int node, re_node_set *eps_via_nodes, + struct re_fail_stack_t *fs)); +static reg_errcode_t push_fail_stack _RE_ARGS((struct re_fail_stack_t *fs, + int str_idx, int *dests, int nregs, + regmatch_t *regs, + re_node_set *eps_via_nodes)); +static int pop_fail_stack _RE_ARGS((struct re_fail_stack_t *fs, int *pidx, int nregs, + regmatch_t *regs, re_node_set *eps_via_nodes)); +static reg_errcode_t set_regs _RE_ARGS((const regex_t *preg, + const re_match_context_t *mctx, + size_t nmatch, regmatch_t *pmatch, + int fl_backtrack)); +static reg_errcode_t free_fail_stack_return _RE_ARGS((struct re_fail_stack_t *fs)); + +#ifdef RE_ENABLE_I18N +static int sift_states_iter_mb _RE_ARGS((const regex_t *preg, + const re_match_context_t *mctx, + re_sift_context_t *sctx, + int node_idx, int str_idx, int max_str_idx)); +#endif /* RE_ENABLE_I18N */ +static reg_errcode_t sift_states_backward _RE_ARGS((const regex_t *preg, + re_match_context_t *mctx, + re_sift_context_t *sctx)); +static reg_errcode_t update_cur_sifted_state _RE_ARGS((const regex_t *preg, + re_match_context_t *mctx, + re_sift_context_t *sctx, + int str_idx, + re_node_set *dest_nodes)); +static reg_errcode_t add_epsilon_src_nodes _RE_ARGS((re_dfa_t *dfa, + re_node_set *dest_nodes, + const re_node_set *candidates)); +static reg_errcode_t sub_epsilon_src_nodes _RE_ARGS((re_dfa_t *dfa, int node, + re_node_set *dest_nodes, + const re_node_set *and_nodes)); +static int check_dst_limits _RE_ARGS((re_dfa_t *dfa, re_node_set *limits, + re_match_context_t *mctx, int dst_node, + int dst_idx, int src_node, int src_idx)); +static int check_dst_limits_calc_pos _RE_ARGS((re_dfa_t *dfa, re_match_context_t *mctx, + int limit, re_node_set *eclosures, + int subexp_idx, int node, int str_idx)); +static reg_errcode_t check_subexp_limits _RE_ARGS((re_dfa_t *dfa, + re_node_set *dest_nodes, + const re_node_set *candidates, + re_node_set *limits, + struct re_backref_cache_entry *bkref_ents, + int str_idx)); +static reg_errcode_t sift_states_bkref _RE_ARGS((const regex_t *preg, + re_match_context_t *mctx, + re_sift_context_t *sctx, + int str_idx, re_node_set *dest_nodes)); +static reg_errcode_t clean_state_log_if_need _RE_ARGS((re_match_context_t *mctx, + int next_state_log_idx)); +static reg_errcode_t merge_state_array _RE_ARGS((re_dfa_t *dfa, re_dfastate_t **dst, + re_dfastate_t **src, int num)); +static re_dfastate_t *transit_state _RE_ARGS((reg_errcode_t *err, const regex_t *preg, + re_match_context_t *mctx, + re_dfastate_t *state, int fl_search)); +static reg_errcode_t check_subexp_matching_top _RE_ARGS((re_dfa_t *dfa, + re_match_context_t *mctx, + re_node_set *cur_nodes, + int str_idx)); +static re_dfastate_t *transit_state_sb _RE_ARGS((reg_errcode_t *err, const regex_t *preg, + re_dfastate_t *pstate, + int fl_search, + re_match_context_t *mctx)); +#ifdef RE_ENABLE_I18N +static reg_errcode_t transit_state_mb _RE_ARGS((const regex_t *preg, + re_dfastate_t *pstate, + re_match_context_t *mctx)); +#endif /* RE_ENABLE_I18N */ +static reg_errcode_t transit_state_bkref _RE_ARGS((const regex_t *preg, + re_node_set *nodes, + re_match_context_t *mctx)); +static reg_errcode_t get_subexp _RE_ARGS((const regex_t *preg, re_match_context_t *mctx, + int bkref_node, int bkref_str_idx)); +static reg_errcode_t get_subexp_sub _RE_ARGS((const regex_t *preg, + re_match_context_t *mctx, + re_sub_match_top_t *sub_top, + re_sub_match_last_t *sub_last, + int bkref_node, int bkref_str)); +static int find_subexp_node _RE_ARGS((re_dfa_t *dfa, re_node_set *nodes, + int subexp_idx, int fl_open)); +static reg_errcode_t check_arrival _RE_ARGS((const regex_t *preg, + re_match_context_t *mctx, + state_array_t *path, int top_node, + int top_str, int last_node, int last_str, + int fl_open)); +static reg_errcode_t check_arrival_add_next_nodes _RE_ARGS((const regex_t *preg, + re_dfa_t *dfa, + re_match_context_t *mctx, + int str_idx, + re_node_set *cur_nodes, + re_node_set *next_nodes)); +static reg_errcode_t check_arrival_expand_ecl _RE_ARGS((re_dfa_t *dfa, + re_node_set *cur_nodes, + int ex_subexp, int fl_open)); +static reg_errcode_t check_arrival_expand_ecl_sub _RE_ARGS((re_dfa_t *dfa, + re_node_set *dst_nodes, + int target, int ex_subexp, + int fl_open)); +static reg_errcode_t expand_bkref_cache _RE_ARGS((const regex_t *preg, + re_match_context_t *mctx, + re_node_set *cur_nodes, int cur_str, + int last_str, int subexp_num, + int fl_open)); +static re_dfastate_t **build_trtable _RE_ARGS((const regex_t *dfa, + const re_dfastate_t *state, + int fl_search)); +#ifdef RE_ENABLE_I18N +static int check_node_accept_bytes _RE_ARGS((const regex_t *preg, int node_idx, + const re_string_t *input, int idx)); +# ifdef _LIBC +static unsigned int find_collation_sequence_value _RE_ARGS((const unsigned char *mbs, + size_t name_len)); +# endif /* _LIBC */ +#endif /* RE_ENABLE_I18N */ +static int group_nodes_into_DFAstates _RE_ARGS((const regex_t *dfa, + const re_dfastate_t *state, + re_node_set *states_node, + bitset *states_ch)); +static int check_node_accept _RE_ARGS((const regex_t *preg, const re_token_t *node, + const re_match_context_t *mctx, int idx)); +static reg_errcode_t extend_buffers _RE_ARGS((re_match_context_t *mctx)); + +/* Entry point for POSIX code. */ + +/* regexec searches for a given pattern, specified by PREG, in the + string STRING. + + If NMATCH is zero or REG_NOSUB was set in the cflags argument to + `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at + least NMATCH elements, and we set them to the offsets of the + corresponding matched substrings. + + EFLAGS specifies `execution flags' which affect matching: if + REG_NOTBOL is set, then ^ does not match at the beginning of the + string; if REG_NOTEOL is set, then $ does not match at the end. + + We return 0 if we find a match and REG_NOMATCH if not. */ + +int +regexec (preg, string, nmatch, pmatch, eflags) + const regex_t *__restrict preg; + const char *__restrict string; + size_t nmatch; + regmatch_t pmatch[]; + int eflags; +{ + reg_errcode_t err; + int length = strlen (string); + if (preg->no_sub) + err = re_search_internal (preg, string, length, 0, length, length, 0, + NULL, eflags); + else + err = re_search_internal (preg, string, length, 0, length, length, nmatch, + pmatch, eflags); + return err != REG_NOERROR; +} +#ifdef _LIBC +weak_alias (__regexec, regexec) +#endif + +/* Entry points for GNU code. */ + +/* re_match, re_search, re_match_2, re_search_2 + + The former two functions operate on STRING with length LENGTH, + while the later two operate on concatenation of STRING1 and STRING2 + with lengths LENGTH1 and LENGTH2, respectively. + + re_match() matches the compiled pattern in BUFP against the string, + starting at index START. + + re_search() first tries matching at index START, then it tries to match + starting from index START + 1, and so on. The last start position tried + is START + RANGE. (Thus RANGE = 0 forces re_search to operate the same + way as re_match().) + + The parameter STOP of re_{match,search}_2 specifies that no match exceeding + the first STOP characters of the concatenation of the strings should be + concerned. + + If REGS is not NULL, and BUFP->no_sub is not set, the offsets of the match + and all groups is stroed in REGS. (For the "_2" variants, the offsets are + computed relative to the concatenation, not relative to the individual + strings.) + + On success, re_match* functions return the length of the match, re_search* + return the position of the start of the match. Return value -1 means no + match was found and -2 indicates an internal error. */ + +int +re_match (bufp, string, length, start, regs) + struct re_pattern_buffer *bufp; + const char *string; + int length, start; + struct re_registers *regs; +{ + return re_search_stub (bufp, string, length, start, 0, length, regs, 1); +} +#ifdef _LIBC +weak_alias (__re_match, re_match) +#endif + +int +re_search (bufp, string, length, start, range, regs) + struct re_pattern_buffer *bufp; + const char *string; + int length, start, range; + struct re_registers *regs; +{ + return re_search_stub (bufp, string, length, start, range, length, regs, 0); +} +#ifdef _LIBC +weak_alias (__re_search, re_search) +#endif + +int +re_match_2 (bufp, string1, length1, string2, length2, start, regs, stop) + struct re_pattern_buffer *bufp; + const char *string1, *string2; + int length1, length2, start, stop; + struct re_registers *regs; +{ + return re_search_2_stub (bufp, string1, length1, string2, length2, + start, 0, regs, stop, 1); +} +#ifdef _LIBC +weak_alias (__re_match_2, re_match_2) +#endif + +int +re_search_2 (bufp, string1, length1, string2, length2, start, range, regs, stop) + struct re_pattern_buffer *bufp; + const char *string1, *string2; + int length1, length2, start, range, stop; + struct re_registers *regs; +{ + return re_search_2_stub (bufp, string1, length1, string2, length2, + start, range, regs, stop, 0); +} +#ifdef _LIBC +weak_alias (__re_search_2, re_search_2) +#endif + +static int +re_search_2_stub (bufp, string1, length1, string2, length2, start, range, regs, + stop, ret_len) + struct re_pattern_buffer *bufp; + const char *string1, *string2; + int length1, length2, start, range, stop, ret_len; + struct re_registers *regs; +{ + const char *str; + int rval; + int len = length1 + length2; + int free_str = 0; + + if (BE (length1 < 0 || length2 < 0 || stop < 0, 0)) + return -2; + + /* Concatenate the strings. */ + if (length2 > 0) + if (length1 > 0) + { + char *s = re_malloc (char, len); + + if (BE (s == NULL, 0)) + return -2; + memcpy (s, string1, length1); + memcpy (s + length1, string2, length2); + str = s; + free_str = 1; + } + else + str = string2; + else + str = string1; + + rval = re_search_stub (bufp, str, len, start, range, stop, regs, + ret_len); + if (free_str) + re_free ((char *) str); + return rval; +} + +/* The parameters have the same meaning as those of re_search. + Additional parameters: + If RET_LEN is nonzero the length of the match is returned (re_match style); + otherwise the position of the match is returned. */ + +static int +re_search_stub (bufp, string, length, start, range, stop, regs, ret_len) + struct re_pattern_buffer *bufp; + const char *string; + int length, start, range, stop, ret_len; + struct re_registers *regs; +{ + reg_errcode_t result; + regmatch_t *pmatch; + int nregs, rval; + int eflags = 0; + + /* Check for out-of-range. */ + if (BE (start < 0 || start > length, 0)) + return -1; + if (BE (start + range > length, 0)) + range = length - start; + else if (BE (start + range < 0, 0)) + range = -start; + + eflags |= (bufp->not_bol) ? REG_NOTBOL : 0; + eflags |= (bufp->not_eol) ? REG_NOTEOL : 0; + + /* Compile fastmap if we haven't yet. */ + if (range > 0 && bufp->fastmap != NULL && !bufp->fastmap_accurate) + re_compile_fastmap (bufp); + + if (BE (bufp->no_sub, 0)) + regs = NULL; + + /* We need at least 1 register. */ + if (regs == NULL) + nregs = 1; + else if (BE (bufp->regs_allocated == REGS_FIXED && + regs->num_regs < bufp->re_nsub + 1, 0)) + { + nregs = regs->num_regs; + if (BE (nregs < 1, 0)) + { + /* Nothing can be copied to regs. */ + regs = NULL; + nregs = 1; + } + } + else + nregs = bufp->re_nsub + 1; + pmatch = re_malloc (regmatch_t, nregs); + if (BE (pmatch == NULL, 0)) + return -2; + + result = re_search_internal (bufp, string, length, start, range, stop, + nregs, pmatch, eflags); + + rval = 0; + + /* I hope we needn't fill ther regs with -1's when no match was found. */ + if (result != REG_NOERROR) + rval = -1; + else if (regs != NULL) + { + /* If caller wants register contents data back, copy them. */ + bufp->regs_allocated = re_copy_regs (regs, pmatch, nregs, + bufp->regs_allocated); + if (BE (bufp->regs_allocated == REGS_UNALLOCATED, 0)) + rval = -2; + } + + if (BE (rval == 0, 1)) + { + if (ret_len) + { + assert (pmatch[0].rm_so == start); + rval = pmatch[0].rm_eo - start; + } + else + rval = pmatch[0].rm_so; + } + re_free (pmatch); + return rval; +} + +static unsigned +re_copy_regs (regs, pmatch, nregs, regs_allocated) + struct re_registers *regs; + regmatch_t *pmatch; + int nregs, regs_allocated; +{ + int rval = REGS_REALLOCATE; + int i; + int need_regs = nregs + 1; + /* We need one extra element beyond `num_regs' for the `-1' marker GNU code + uses. */ + + /* Have the register data arrays been allocated? */ + if (regs_allocated == REGS_UNALLOCATED) + { /* No. So allocate them with malloc. */ + regs->start = re_malloc (regoff_t, need_regs); + if (BE (regs->start == NULL, 0)) + return REGS_UNALLOCATED; + regs->end = re_malloc (regoff_t, need_regs); + if (BE (regs->end == NULL, 0)) + { + re_free (regs->start); + return REGS_UNALLOCATED; + } + regs->num_regs = need_regs; + } + else if (regs_allocated == REGS_REALLOCATE) + { /* Yes. If we need more elements than were already + allocated, reallocate them. If we need fewer, just + leave it alone. */ + if (need_regs > regs->num_regs) + { + regs->start = re_realloc (regs->start, regoff_t, need_regs); + if (BE (regs->start == NULL, 0)) + { + if (regs->end != NULL) + re_free (regs->end); + return REGS_UNALLOCATED; + } + regs->end = re_realloc (regs->end, regoff_t, need_regs); + if (BE (regs->end == NULL, 0)) + { + re_free (regs->start); + return REGS_UNALLOCATED; + } + regs->num_regs = need_regs; + } + } + else + { + assert (regs_allocated == REGS_FIXED); + /* This function may not be called with REGS_FIXED and nregs too big. */ + assert (regs->num_regs >= nregs); + rval = REGS_FIXED; + } + + /* Copy the regs. */ + for (i = 0; i < nregs; ++i) + { + regs->start[i] = pmatch[i].rm_so; + regs->end[i] = pmatch[i].rm_eo; + } + for ( ; i < regs->num_regs; ++i) + regs->start[i] = regs->end[i] = -1; + + return rval; +} + +/* Set REGS to hold NUM_REGS registers, storing them in STARTS and + ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use + this memory for recording register information. STARTS and ENDS + must be allocated using the malloc library routine, and must each + be at least NUM_REGS * sizeof (regoff_t) bytes long. + + If NUM_REGS == 0, then subsequent matches should allocate their own + register data. + + Unless this function is called, the first search or match using + PATTERN_BUFFER will allocate its own register data, without + freeing the old data. */ + +void +re_set_registers (bufp, regs, num_regs, starts, ends) + struct re_pattern_buffer *bufp; + struct re_registers *regs; + unsigned num_regs; + regoff_t *starts, *ends; +{ + if (num_regs) + { + bufp->regs_allocated = REGS_REALLOCATE; + regs->num_regs = num_regs; + regs->start = starts; + regs->end = ends; + } + else + { + bufp->regs_allocated = REGS_UNALLOCATED; + regs->num_regs = 0; + regs->start = regs->end = (regoff_t *) 0; + } +} +#ifdef _LIBC +weak_alias (__re_set_registers, re_set_registers) +#endif + +/* Entry points compatible with 4.2 BSD regex library. We don't define + them unless specifically requested. */ + +#if defined _REGEX_RE_COMP || defined _LIBC +int +# ifdef _LIBC +weak_function +# endif +re_exec (s) + const char *s; +{ + return 0 == regexec (&re_comp_buf, s, 0, NULL, 0); +} +#endif /* _REGEX_RE_COMP */ + +static re_node_set empty_set; + +/* Internal entry point. */ + +/* Searches for a compiled pattern PREG in the string STRING, whose + length is LENGTH. NMATCH, PMATCH, and EFLAGS have the same + mingings with regexec. START, and RANGE have the same meanings + with re_search. + Return REG_NOERROR if we find a match, and REG_NOMATCH if not, + otherwise return the error code. + Note: We assume front end functions already check ranges. + (START + RANGE >= 0 && START + RANGE <= LENGTH) */ + +static reg_errcode_t +re_search_internal (preg, string, length, start, range, stop, nmatch, pmatch, + eflags) + const regex_t *preg; + const char *string; + int length, start, range, stop, eflags; + size_t nmatch; + regmatch_t pmatch[]; +{ + reg_errcode_t err; + re_dfa_t *dfa = (re_dfa_t *)preg->buffer; + re_string_t input; + int left_lim, right_lim, incr; + int fl_longest_match, match_first, match_last = -1; + int fast_translate, sb; + re_match_context_t mctx; + char *fastmap = ((preg->fastmap != NULL && preg->fastmap_accurate + && range && !preg->can_be_null) ? preg->fastmap : NULL); + + /* Check if the DFA haven't been compiled. */ + if (BE (preg->used == 0 || dfa->init_state == NULL + || dfa->init_state_word == NULL || dfa->init_state_nl == NULL + || dfa->init_state_begbuf == NULL, 0)) + return REG_NOMATCH; + + re_node_set_init_empty (&empty_set); + memset (&mctx, '\0', sizeof (re_match_context_t)); + + /* We must check the longest matching, if nmatch > 0. */ + fl_longest_match = (nmatch != 0 || dfa->nbackref); + + err = re_string_allocate (&input, string, length, dfa->nodes_len + 1, + preg->translate, preg->syntax & RE_ICASE); + if (BE (err != REG_NOERROR, 0)) + goto free_return; + input.stop = stop; + + err = match_ctx_init (&mctx, eflags, &input, dfa->nbackref * 2); + if (BE (err != REG_NOERROR, 0)) + goto free_return; + + /* We will log all the DFA states through which the dfa pass, + if nmatch > 1, or this dfa has "multibyte node", which is a + back-reference or a node which can accept multibyte character or + multi character collating element. */ + if (nmatch > 1 || dfa->has_mb_node) + { + mctx.state_log = re_malloc (re_dfastate_t *, dfa->nodes_len + 1); + if (BE (mctx.state_log == NULL, 0)) + { + err = REG_ESPACE; + goto free_return; + } + } + else + mctx.state_log = NULL; + +#ifdef DEBUG + /* We assume front-end functions already check them. */ + assert (start + range >= 0 && start + range <= length); +#endif + + match_first = start; + input.tip_context = ((eflags & REG_NOTBOL) ? CONTEXT_BEGBUF + : CONTEXT_NEWLINE | CONTEXT_BEGBUF); + + /* Check incrementally whether of not the input string match. */ + incr = (range < 0) ? -1 : 1; + left_lim = (range < 0) ? start + range : start; + right_lim = (range < 0) ? start : start + range; +#ifdef RE_ENABLE_I18N + sb = re_mb_cur_max == 1; +#else + sb = 1; +#endif + fast_translate = sb || !(preg->syntax & RE_ICASE || preg->translate); + + for (;;) + { + /* At first get the current byte from input string. */ + if (fastmap) + { + if (BE (fast_translate, 1)) + { + unsigned RE_TRANSLATE_TYPE t + = (unsigned RE_TRANSLATE_TYPE) preg->translate; + if (BE (range >= 0, 1)) + { + if (BE (t != NULL, 0)) + { + while (BE (match_first < right_lim, 1) + && !fastmap[t[(unsigned char) string[match_first]]]) + ++match_first; + } + else + { + while (BE (match_first < right_lim, 1) + && !fastmap[(unsigned char) string[match_first]]) + ++match_first; + } + if (BE (match_first == right_lim, 0)) + { + int ch = match_first >= length + ? 0 : (unsigned char) string[match_first]; + if (!fastmap[t ? t[ch] : ch]) + break; + } + } + else + { + while (match_first >= left_lim) + { + int ch = match_first >= length + ? 0 : (unsigned char) string[match_first]; + if (fastmap[t ? t[ch] : ch]) + break; + --match_first; + } + if (match_first < left_lim) + break; + } + } + else + { + int ch; + + do + { + /* In this case, we can't determine easily the current byte, + since it might be a component byte of a multibyte + character. Then we use the constructed buffer + instead. */ + /* If MATCH_FIRST is out of the valid range, reconstruct the + buffers. */ + if (input.raw_mbs_idx + input.valid_len <= match_first + || match_first < input.raw_mbs_idx) + { + err = re_string_reconstruct (&input, match_first, eflags, + preg->newline_anchor); + if (BE (err != REG_NOERROR, 0)) + goto free_return; + } + /* If MATCH_FIRST is out of the buffer, leave it as '\0'. + Note that MATCH_FIRST must not be smaller than 0. */ + ch = ((match_first >= length) ? 0 + : re_string_byte_at (&input, + match_first - input.raw_mbs_idx)); + if (fastmap[ch]) + break; + match_first += incr; + } + while (match_first >= left_lim && match_first <= right_lim); + if (! fastmap[ch]) + break; + } + } + + /* Reconstruct the buffers so that the matcher can assume that + the matching starts from the begining of the buffer. */ + err = re_string_reconstruct (&input, match_first, eflags, + preg->newline_anchor); + if (BE (err != REG_NOERROR, 0)) + goto free_return; +#ifdef RE_ENABLE_I18N + /* Eliminate it when it is a component of a multibyte character + and isn't the head of a multibyte character. */ + if (sb || re_string_first_byte (&input, 0)) +#endif + { + /* It seems to be appropriate one, then use the matcher. */ + /* We assume that the matching starts from 0. */ + mctx.state_log_top = mctx.nbkref_ents = mctx.max_mb_elem_len = 0; + match_last = check_matching (preg, &mctx, 0, fl_longest_match); + if (match_last != -1) + { + if (BE (match_last == -2, 0)) + { + err = REG_ESPACE; + goto free_return; + } + else + { + mctx.match_last = match_last; + if ((!preg->no_sub && nmatch > 1) || dfa->nbackref) + { + re_dfastate_t *pstate = mctx.state_log[match_last]; + mctx.last_node = check_halt_state_context (preg, pstate, + &mctx, match_last); + } + if ((!preg->no_sub && nmatch > 1 && dfa->has_plural_match) + || dfa->nbackref) + { + err = prune_impossible_nodes (preg, &mctx); + if (err == REG_NOERROR) + break; + if (BE (err != REG_NOMATCH, 0)) + goto free_return; + } + else + break; /* We found a matching. */ + } + } + match_ctx_clean (&mctx); + } + /* Update counter. */ + match_first += incr; + if (match_first < left_lim || right_lim < match_first) + break; + } + + /* Set pmatch[] if we need. */ + if (match_last != -1 && nmatch > 0) + { + int reg_idx; + + /* Initialize registers. */ + for (reg_idx = 0; reg_idx < nmatch; ++reg_idx) + pmatch[reg_idx].rm_so = pmatch[reg_idx].rm_eo = -1; + + /* Set the points where matching start/end. */ + pmatch[0].rm_so = 0; + pmatch[0].rm_eo = mctx.match_last; + + if (!preg->no_sub && nmatch > 1) + { + err = set_regs (preg, &mctx, nmatch, pmatch, + dfa->has_plural_match && dfa->nbackref > 0); + if (BE (err != REG_NOERROR, 0)) + goto free_return; + } + + /* At last, add the offset to the each registers, since we slided + the buffers so that We can assume that the matching starts from 0. */ + for (reg_idx = 0; reg_idx < nmatch; ++reg_idx) + if (pmatch[reg_idx].rm_so != -1) + { + pmatch[reg_idx].rm_so += match_first; + pmatch[reg_idx].rm_eo += match_first; + } + } + err = (match_last == -1) ? REG_NOMATCH : REG_NOERROR; + free_return: + re_free (mctx.state_log); + if (dfa->nbackref) + match_ctx_free (&mctx); + re_string_destruct (&input); + return err; +} + +static reg_errcode_t +prune_impossible_nodes (preg, mctx) + const regex_t *preg; + re_match_context_t *mctx; +{ + int halt_node, match_last; + reg_errcode_t ret; + re_dfa_t *dfa = (re_dfa_t *)preg->buffer; + re_dfastate_t **sifted_states; + re_dfastate_t **lim_states = NULL; + re_sift_context_t sctx; +#ifdef DEBUG + assert (mctx->state_log != NULL); +#endif + match_last = mctx->match_last; + halt_node = mctx->last_node; + sifted_states = re_malloc (re_dfastate_t *, match_last + 1); + if (BE (sifted_states == NULL, 0)) + { + ret = REG_ESPACE; + goto free_return; + } + if (dfa->nbackref) + { + lim_states = re_malloc (re_dfastate_t *, match_last + 1); + if (BE (lim_states == NULL, 0)) + { + ret = REG_ESPACE; + goto free_return; + } + while (1) + { + memset (lim_states, '\0', + sizeof (re_dfastate_t *) * (match_last + 1)); + match_ctx_clear_flag (mctx); + sift_ctx_init (&sctx, sifted_states, lim_states, halt_node, + match_last, 0); + ret = sift_states_backward (preg, mctx, &sctx); + re_node_set_free (&sctx.limits); + if (BE (ret != REG_NOERROR, 0)) + goto free_return; + if (sifted_states[0] != NULL || lim_states[0] != NULL) + break; + do + { + --match_last; + if (match_last < 0) + { + ret = REG_NOMATCH; + goto free_return; + } + } while (!mctx->state_log[match_last]->halt); + halt_node = check_halt_state_context (preg, + mctx->state_log[match_last], + mctx, match_last); + } + ret = merge_state_array (dfa, sifted_states, lim_states, + match_last + 1); + re_free (lim_states); + lim_states = NULL; + if (BE (ret != REG_NOERROR, 0)) + goto free_return; + } + else + { + sift_ctx_init (&sctx, sifted_states, lim_states, halt_node, + match_last, 0); + ret = sift_states_backward (preg, mctx, &sctx); + re_node_set_free (&sctx.limits); + if (BE (ret != REG_NOERROR, 0)) + goto free_return; + } + re_free (mctx->state_log); + mctx->state_log = sifted_states; + sifted_states = NULL; + mctx->last_node = halt_node; + mctx->match_last = match_last; + ret = REG_NOERROR; + free_return: + re_free (sifted_states); + re_free (lim_states); + return ret; +} + +/* Acquire an initial state and return it. + We must select appropriate initial state depending on the context, + since initial states may have constraints like "\<", "^", etc.. */ + +static inline re_dfastate_t * +acquire_init_state_context (err, preg, mctx, idx) + reg_errcode_t *err; + const regex_t *preg; + const re_match_context_t *mctx; + int idx; +{ + re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + + *err = REG_NOERROR; + if (dfa->init_state->has_constraint) + { + unsigned int context; + context = re_string_context_at (mctx->input, idx - 1, mctx->eflags, + preg->newline_anchor); + if (IS_WORD_CONTEXT (context)) + return dfa->init_state_word; + else if (IS_ORDINARY_CONTEXT (context)) + return dfa->init_state; + else if (IS_BEGBUF_CONTEXT (context) && IS_NEWLINE_CONTEXT (context)) + return dfa->init_state_begbuf; + else if (IS_NEWLINE_CONTEXT (context)) + return dfa->init_state_nl; + else if (IS_BEGBUF_CONTEXT (context)) + { + /* It is relatively rare case, then calculate on demand. */ + return re_acquire_state_context (err, dfa, + dfa->init_state->entrance_nodes, + context); + } + else + /* Must not happen? */ + return dfa->init_state; + } + else + return dfa->init_state; +} + +/* Check whether the regular expression match input string INPUT or not, + and return the index where the matching end, return -1 if not match, + or return -2 in case of an error. + FL_SEARCH means we must search where the matching starts, + FL_LONGEST_MATCH means we want the POSIX longest matching. + Note that the matcher assume that the maching starts from the current + index of the buffer. */ + +static int +check_matching (preg, mctx, fl_search, fl_longest_match) + const regex_t *preg; + re_match_context_t *mctx; + int fl_search, fl_longest_match; +{ + re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + reg_errcode_t err; + int match = 0; + int match_last = -1; + int cur_str_idx = re_string_cur_idx (mctx->input); + re_dfastate_t *cur_state; + + cur_state = acquire_init_state_context (&err, preg, mctx, cur_str_idx); + /* An initial state must not be NULL(invalid state). */ + if (BE (cur_state == NULL, 0)) + return -2; + if (mctx->state_log != NULL) + mctx->state_log[cur_str_idx] = cur_state; + + /* Check OP_OPEN_SUBEXP in the initial state in case that we use them + later. E.g. Processing back references. */ + if (dfa->nbackref) + { + err = check_subexp_matching_top (dfa, mctx, &cur_state->nodes, 0); + if (BE (err != REG_NOERROR, 0)) + return err; + } + + if (cur_state->has_backref) + { + err = transit_state_bkref (preg, &cur_state->nodes, mctx); + if (BE (err != REG_NOERROR, 0)) + return err; + } + + /* If the RE accepts NULL string. */ + if (cur_state->halt) + { + if (!cur_state->has_constraint + || check_halt_state_context (preg, cur_state, mctx, cur_str_idx)) + { + if (!fl_longest_match) + return cur_str_idx; + else + { + match_last = cur_str_idx; + match = 1; + } + } + } + + while (!re_string_eoi (mctx->input)) + { + cur_state = transit_state (&err, preg, mctx, cur_state, + fl_search && !match); + if (cur_state == NULL) /* Reached at the invalid state or an error. */ + { + cur_str_idx = re_string_cur_idx (mctx->input); + if (BE (err != REG_NOERROR, 0)) + return -2; + if (fl_search && !match) + { + /* Restart from initial state, since we are searching + the point from where matching start. */ +#ifdef RE_ENABLE_I18N + if (re_mb_cur_max == 1 + || re_string_first_byte (mctx->input, cur_str_idx)) +#endif /* RE_ENABLE_I18N */ + cur_state = acquire_init_state_context (&err, preg, mctx, + cur_str_idx); + if (BE (cur_state == NULL && err != REG_NOERROR, 0)) + return -2; + if (mctx->state_log != NULL) + mctx->state_log[cur_str_idx] = cur_state; + } + else if (!fl_longest_match && match) + break; + else /* (fl_longest_match && match) || (!fl_search && !match) */ + { + if (mctx->state_log == NULL) + break; + else + { + int max = mctx->state_log_top; + for (; cur_str_idx <= max; ++cur_str_idx) + if (mctx->state_log[cur_str_idx] != NULL) + break; + if (cur_str_idx > max) + break; + } + } + } + + if (cur_state != NULL && cur_state->halt) + { + /* Reached at a halt state. + Check the halt state can satisfy the current context. */ + if (!cur_state->has_constraint + || check_halt_state_context (preg, cur_state, mctx, + re_string_cur_idx (mctx->input))) + { + /* We found an appropriate halt state. */ + match_last = re_string_cur_idx (mctx->input); + match = 1; + if (!fl_longest_match) + break; + } + } + } + return match_last; +} + +/* Check NODE match the current context. */ + +static int check_halt_node_context (dfa, node, context) + const re_dfa_t *dfa; + int node; + unsigned int context; +{ + re_token_type_t type = dfa->nodes[node].type; + unsigned int constraint = dfa->nodes[node].constraint; + if (type != END_OF_RE) + return 0; + if (!constraint) + return 1; + if (NOT_SATISFY_NEXT_CONSTRAINT (constraint, context)) + return 0; + return 1; +} + +/* Check the halt state STATE match the current context. + Return 0 if not match, if the node, STATE has, is a halt node and + match the context, return the node. */ + +static int +check_halt_state_context (preg, state, mctx, idx) + const regex_t *preg; + const re_dfastate_t *state; + const re_match_context_t *mctx; + int idx; +{ + re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + int i; + unsigned int context; +#ifdef DEBUG + assert (state->halt); +#endif + context = re_string_context_at (mctx->input, idx, mctx->eflags, + preg->newline_anchor); + for (i = 0; i < state->nodes.nelem; ++i) + if (check_halt_node_context (dfa, state->nodes.elems[i], context)) + return state->nodes.elems[i]; + return 0; +} + +/* Compute the next node to which "NFA" transit from NODE("NFA" is a NFA + corresponding to the DFA). + Return the destination node, and update EPS_VIA_NODES, return -1 in case + of errors. */ + +static int +proceed_next_node (preg, nregs, regs, mctx, pidx, node, eps_via_nodes, fs) + const regex_t *preg; + regmatch_t *regs; + const re_match_context_t *mctx; + int nregs, *pidx, node; + re_node_set *eps_via_nodes; + struct re_fail_stack_t *fs; +{ + re_dfa_t *dfa = (re_dfa_t *)preg->buffer; + int i, err, dest_node; + dest_node = -1; + if (IS_EPSILON_NODE (dfa->nodes[node].type)) + { + re_node_set *cur_nodes = &mctx->state_log[*pidx]->nodes; + int ndest, dest_nodes[2]; + err = re_node_set_insert (eps_via_nodes, node); + if (BE (err < 0, 0)) + return -1; + /* Pick up valid destinations. */ + for (ndest = 0, i = 0; i < dfa->edests[node].nelem; ++i) + { + int candidate = dfa->edests[node].elems[i]; + if (!re_node_set_contains (cur_nodes, candidate)) + continue; + dest_nodes[0] = (ndest == 0) ? candidate : dest_nodes[0]; + dest_nodes[1] = (ndest == 1) ? candidate : dest_nodes[1]; + ++ndest; + } + if (ndest <= 1) + return ndest == 0 ? -1 : (ndest == 1 ? dest_nodes[0] : 0); + /* In order to avoid infinite loop like "(a*)*". */ + if (re_node_set_contains (eps_via_nodes, dest_nodes[0])) + return dest_nodes[1]; + if (fs != NULL) + push_fail_stack (fs, *pidx, dest_nodes, nregs, regs, eps_via_nodes); + return dest_nodes[0]; + } + else + { + int naccepted = 0; + re_token_type_t type = dfa->nodes[node].type; + +#ifdef RE_ENABLE_I18N + if (ACCEPT_MB_NODE (type)) + naccepted = check_node_accept_bytes (preg, node, mctx->input, *pidx); + else +#endif /* RE_ENABLE_I18N */ + if (type == OP_BACK_REF) + { + int subexp_idx = dfa->nodes[node].opr.idx; + naccepted = regs[subexp_idx].rm_eo - regs[subexp_idx].rm_so; + if (fs != NULL) + { + if (regs[subexp_idx].rm_so == -1 || regs[subexp_idx].rm_eo == -1) + return -1; + else if (naccepted) + { + char *buf = (char *) re_string_get_buffer (mctx->input); + if (memcmp (buf + regs[subexp_idx].rm_so, buf + *pidx, + naccepted) != 0) + return -1; + } + } + + if (naccepted == 0) + { + err = re_node_set_insert (eps_via_nodes, node); + if (BE (err < 0, 0)) + return -2; + dest_node = dfa->edests[node].elems[0]; + if (re_node_set_contains (&mctx->state_log[*pidx]->nodes, + dest_node)) + return dest_node; + } + } + + if (naccepted != 0 + || check_node_accept (preg, dfa->nodes + node, mctx, *pidx)) + { + dest_node = dfa->nexts[node]; + *pidx = (naccepted == 0) ? *pidx + 1 : *pidx + naccepted; + if (fs && (*pidx > mctx->match_last || mctx->state_log[*pidx] == NULL + || !re_node_set_contains (&mctx->state_log[*pidx]->nodes, + dest_node))) + return -1; + re_node_set_empty (eps_via_nodes); + return dest_node; + } + } + return -1; +} + +static reg_errcode_t +push_fail_stack (fs, str_idx, dests, nregs, regs, eps_via_nodes) + struct re_fail_stack_t *fs; + int str_idx, *dests, nregs; + regmatch_t *regs; + re_node_set *eps_via_nodes; +{ + reg_errcode_t err; + int num = fs->num++; + if (fs->num == fs->alloc) + { + struct re_fail_stack_ent_t *new_array; + fs->alloc *= 2; + new_array = realloc (fs->stack, (sizeof (struct re_fail_stack_ent_t) + * fs->alloc)); + if (new_array == NULL) + return REG_ESPACE; + fs->stack = new_array; + } + fs->stack[num].idx = str_idx; + fs->stack[num].node = dests[1]; + fs->stack[num].regs = re_malloc (regmatch_t, nregs); + memcpy (fs->stack[num].regs, regs, sizeof (regmatch_t) * nregs); + err = re_node_set_init_copy (&fs->stack[num].eps_via_nodes, eps_via_nodes); + return err; +} + +static int +pop_fail_stack (fs, pidx, nregs, regs, eps_via_nodes) + struct re_fail_stack_t *fs; + int *pidx, nregs; + regmatch_t *regs; + re_node_set *eps_via_nodes; +{ + int num = --fs->num; + assert (num >= 0); + *pidx = fs->stack[num].idx; + memcpy (regs, fs->stack[num].regs, sizeof (regmatch_t) * nregs); + re_node_set_free (eps_via_nodes); + re_free (fs->stack[num].regs); + *eps_via_nodes = fs->stack[num].eps_via_nodes; + return fs->stack[num].node; +} + +/* Set the positions where the subexpressions are starts/ends to registers + PMATCH. + Note: We assume that pmatch[0] is already set, and + pmatch[i].rm_so == pmatch[i].rm_eo == -1 (i > 1). */ + +static reg_errcode_t +set_regs (preg, mctx, nmatch, pmatch, fl_backtrack) + const regex_t *preg; + const re_match_context_t *mctx; + size_t nmatch; + regmatch_t *pmatch; + int fl_backtrack; +{ + re_dfa_t *dfa = (re_dfa_t *)preg->buffer; + int idx, cur_node, real_nmatch; + re_node_set eps_via_nodes; + struct re_fail_stack_t *fs; + struct re_fail_stack_t fs_body; + fs_body.num = 0; + fs_body.alloc = 2; + fs_body.stack = NULL; +#ifdef DEBUG + assert (nmatch > 1); + assert (mctx->state_log != NULL); +#endif + if (fl_backtrack) + { + fs = &fs_body; + fs->stack = re_malloc (struct re_fail_stack_ent_t, fs->alloc); + } + else + fs = NULL; + cur_node = dfa->init_node; + real_nmatch = (nmatch <= preg->re_nsub) ? nmatch : preg->re_nsub + 1; + re_node_set_init_empty (&eps_via_nodes); + for (idx = pmatch[0].rm_so; idx <= pmatch[0].rm_eo ;) + { + update_regs (dfa, pmatch, cur_node, idx, real_nmatch); + if (idx == pmatch[0].rm_eo && cur_node == mctx->last_node) + { + int reg_idx; + if (fs) + { + for (reg_idx = 0; reg_idx < nmatch; ++reg_idx) + if (pmatch[reg_idx].rm_so > -1 && pmatch[reg_idx].rm_eo == -1) + break; + if (reg_idx == nmatch) + { + re_node_set_free (&eps_via_nodes); + return free_fail_stack_return (fs); + } + cur_node = pop_fail_stack (fs, &idx, nmatch, pmatch, + &eps_via_nodes); + } + else + { + re_node_set_free (&eps_via_nodes); + return REG_NOERROR; + } + } + + /* Proceed to next node. */ + cur_node = proceed_next_node (preg, nmatch, pmatch, mctx, &idx, cur_node, + &eps_via_nodes, fs); + + if (BE (cur_node < 0, 0)) + { + if (cur_node == -2) + return REG_ESPACE; + if (fs) + cur_node = pop_fail_stack (fs, &idx, nmatch, pmatch, + &eps_via_nodes); + else + { + re_node_set_free (&eps_via_nodes); + return REG_NOMATCH; + } + } + } + re_node_set_free (&eps_via_nodes); + return free_fail_stack_return (fs); +} + +static reg_errcode_t +free_fail_stack_return (fs) + struct re_fail_stack_t *fs; +{ + if (fs) + { + int fs_idx; + for (fs_idx = 0; fs_idx < fs->num; ++fs_idx) + { + re_node_set_free (&fs->stack[fs_idx].eps_via_nodes); + re_free (fs->stack[fs_idx].regs); + } + re_free (fs->stack); + } + return REG_NOERROR; +} + +static void +update_regs (dfa, pmatch, cur_node, cur_idx, nmatch) + re_dfa_t *dfa; + regmatch_t *pmatch; + int cur_node, cur_idx, nmatch; +{ + int type = dfa->nodes[cur_node].type; + int reg_num; + if (type != OP_OPEN_SUBEXP && type != OP_CLOSE_SUBEXP) + return; + reg_num = dfa->nodes[cur_node].opr.idx + 1; + if (reg_num >= nmatch) + return; + if (type == OP_OPEN_SUBEXP) + { + /* We are at the first node of this sub expression. */ + pmatch[reg_num].rm_so = cur_idx; + pmatch[reg_num].rm_eo = -1; + } + else if (type == OP_CLOSE_SUBEXP) + /* We are at the first node of this sub expression. */ + pmatch[reg_num].rm_eo = cur_idx; +} + +#define NUMBER_OF_STATE 1 + +/* This function checks the STATE_LOG from the SCTX->last_str_idx to 0 + and sift the nodes in each states according to the following rules. + Updated state_log will be wrote to STATE_LOG. + + Rules: We throw away the Node `a' in the STATE_LOG[STR_IDX] if... + 1. When STR_IDX == MATCH_LAST(the last index in the state_log): + If `a' isn't the LAST_NODE and `a' can't epsilon transit to + the LAST_NODE, we throw away the node `a'. + 2. When 0 <= STR_IDX < MATCH_LAST and `a' accepts + string `s' and transit to `b': + i. If 'b' isn't in the STATE_LOG[STR_IDX+strlen('s')], we throw + away the node `a'. + ii. If 'b' is in the STATE_LOG[STR_IDX+strlen('s')] but 'b' is + throwed away, we throw away the node `a'. + 3. When 0 <= STR_IDX < n and 'a' epsilon transit to 'b': + i. If 'b' isn't in the STATE_LOG[STR_IDX], we throw away the + node `a'. + ii. If 'b' is in the STATE_LOG[STR_IDX] but 'b' is throwed away, + we throw away the node `a'. */ + +#define STATE_NODE_CONTAINS(state,node) \ + ((state) != NULL && re_node_set_contains (&(state)->nodes, node)) + +static reg_errcode_t +sift_states_backward (preg, mctx, sctx) + const regex_t *preg; + re_match_context_t *mctx; + re_sift_context_t *sctx; +{ + reg_errcode_t err; + re_dfa_t *dfa = (re_dfa_t *)preg->buffer; + int null_cnt = 0; + int str_idx = sctx->last_str_idx; + re_node_set cur_dest; + re_node_set *cur_src; /* Points the state_log[str_idx]->nodes */ + +#ifdef DEBUG + assert (mctx->state_log != NULL && mctx->state_log[str_idx] != NULL); +#endif + cur_src = &mctx->state_log[str_idx]->nodes; + + /* Build sifted state_log[str_idx]. It has the nodes which can epsilon + transit to the last_node and the last_node itself. */ + err = re_node_set_init_1 (&cur_dest, sctx->last_node); + if (BE (err != REG_NOERROR, 0)) + return err; + err = update_cur_sifted_state (preg, mctx, sctx, str_idx, &cur_dest); + if (BE (err != REG_NOERROR, 0)) + goto free_return; + + /* Then check each states in the state_log. */ + while (str_idx > 0) + { + int i, ret; + /* Update counters. */ + null_cnt = (sctx->sifted_states[str_idx] == NULL) ? null_cnt + 1 : 0; + if (null_cnt > mctx->max_mb_elem_len) + { + memset (sctx->sifted_states, '\0', + sizeof (re_dfastate_t *) * str_idx); + re_node_set_free (&cur_dest); + return REG_NOERROR; + } + re_node_set_empty (&cur_dest); + --str_idx; + cur_src = ((mctx->state_log[str_idx] == NULL) ? &empty_set + : &mctx->state_log[str_idx]->nodes); + + /* Then build the next sifted state. + We build the next sifted state on `cur_dest', and update + `sifted_states[str_idx]' with `cur_dest'. + Note: + `cur_dest' is the sifted state from `state_log[str_idx + 1]'. + `cur_src' points the node_set of the old `state_log[str_idx]'. */ + for (i = 0; i < cur_src->nelem; i++) + { + int prev_node = cur_src->elems[i]; + int naccepted = 0; + re_token_type_t type = dfa->nodes[prev_node].type; + + if (IS_EPSILON_NODE(type)) + continue; +#ifdef RE_ENABLE_I18N + /* If the node may accept `multi byte'. */ + if (ACCEPT_MB_NODE (type)) + naccepted = sift_states_iter_mb (preg, mctx, sctx, prev_node, + str_idx, sctx->last_str_idx); + +#endif /* RE_ENABLE_I18N */ + /* We don't check backreferences here. + See update_cur_sifted_state(). */ + + if (!naccepted + && check_node_accept (preg, dfa->nodes + prev_node, mctx, + str_idx) + && STATE_NODE_CONTAINS (sctx->sifted_states[str_idx + 1], + dfa->nexts[prev_node])) + naccepted = 1; + + if (naccepted == 0) + continue; + + if (sctx->limits.nelem) + { + int to_idx = str_idx + naccepted; + if (check_dst_limits (dfa, &sctx->limits, mctx, + dfa->nexts[prev_node], to_idx, + prev_node, str_idx)) + continue; + } + ret = re_node_set_insert (&cur_dest, prev_node); + if (BE (ret == -1, 0)) + { + err = REG_ESPACE; + goto free_return; + } + } + + /* Add all the nodes which satisfy the following conditions: + - It can epsilon transit to a node in CUR_DEST. + - It is in CUR_SRC. + And update state_log. */ + err = update_cur_sifted_state (preg, mctx, sctx, str_idx, &cur_dest); + if (BE (err != REG_NOERROR, 0)) + goto free_return; + } + err = REG_NOERROR; + free_return: + re_node_set_free (&cur_dest); + return err; +} + +/* Helper functions. */ + +static inline reg_errcode_t +clean_state_log_if_need (mctx, next_state_log_idx) + re_match_context_t *mctx; + int next_state_log_idx; +{ + int top = mctx->state_log_top; + + if (next_state_log_idx >= mctx->input->bufs_len + || (next_state_log_idx >= mctx->input->valid_len + && mctx->input->valid_len < mctx->input->len)) + { + reg_errcode_t err; + err = extend_buffers (mctx); + if (BE (err != REG_NOERROR, 0)) + return err; + } + + if (top < next_state_log_idx) + { + memset (mctx->state_log + top + 1, '\0', + sizeof (re_dfastate_t *) * (next_state_log_idx - top)); + mctx->state_log_top = next_state_log_idx; + } + return REG_NOERROR; +} + +static reg_errcode_t +merge_state_array (dfa, dst, src, num) + re_dfa_t *dfa; + re_dfastate_t **dst; + re_dfastate_t **src; + int num; +{ + int st_idx; + reg_errcode_t err; + for (st_idx = 0; st_idx < num; ++st_idx) + { + if (dst[st_idx] == NULL) + dst[st_idx] = src[st_idx]; + else if (src[st_idx] != NULL) + { + re_node_set merged_set; + err = re_node_set_init_union (&merged_set, &dst[st_idx]->nodes, + &src[st_idx]->nodes); + if (BE (err != REG_NOERROR, 0)) + return err; + dst[st_idx] = re_acquire_state (&err, dfa, &merged_set); + re_node_set_free (&merged_set); + if (BE (err != REG_NOERROR, 0)) + return err; + } + } + return REG_NOERROR; +} + +static reg_errcode_t +update_cur_sifted_state (preg, mctx, sctx, str_idx, dest_nodes) + const regex_t *preg; + re_match_context_t *mctx; + re_sift_context_t *sctx; + int str_idx; + re_node_set *dest_nodes; +{ + reg_errcode_t err; + re_dfa_t *dfa = (re_dfa_t *)preg->buffer; + const re_node_set *candidates; + candidates = ((mctx->state_log[str_idx] == NULL) ? &empty_set + : &mctx->state_log[str_idx]->nodes); + + /* At first, add the nodes which can epsilon transit to a node in + DEST_NODE. */ + if (dest_nodes->nelem) + { + err = add_epsilon_src_nodes (dfa, dest_nodes, candidates); + if (BE (err != REG_NOERROR, 0)) + return err; + } + + /* Then, check the limitations in the current sift_context. */ + if (dest_nodes->nelem && sctx->limits.nelem) + { + err = check_subexp_limits (dfa, dest_nodes, candidates, &sctx->limits, + mctx->bkref_ents, str_idx); + if (BE (err != REG_NOERROR, 0)) + return err; + } + + /* Update state_log. */ + sctx->sifted_states[str_idx] = re_acquire_state (&err, dfa, dest_nodes); + if (BE (sctx->sifted_states[str_idx] == NULL && err != REG_NOERROR, 0)) + return err; + + if ((mctx->state_log[str_idx] != NULL + && mctx->state_log[str_idx]->has_backref)) + { + err = sift_states_bkref (preg, mctx, sctx, str_idx, dest_nodes); + if (BE (err != REG_NOERROR, 0)) + return err; + } + return REG_NOERROR; +} + +static reg_errcode_t +add_epsilon_src_nodes (dfa, dest_nodes, candidates) + re_dfa_t *dfa; + re_node_set *dest_nodes; + const re_node_set *candidates; +{ + reg_errcode_t err; + int src_idx; + re_node_set src_copy; + + err = re_node_set_init_copy (&src_copy, dest_nodes); + if (BE (err != REG_NOERROR, 0)) + return err; + for (src_idx = 0; src_idx < src_copy.nelem; ++src_idx) + { + err = re_node_set_add_intersect (dest_nodes, candidates, + dfa->inveclosures + + src_copy.elems[src_idx]); + if (BE (err != REG_NOERROR, 0)) + { + re_node_set_free (&src_copy); + return err; + } + } + re_node_set_free (&src_copy); + return REG_NOERROR; +} + +static reg_errcode_t +sub_epsilon_src_nodes (dfa, node, dest_nodes, candidates) + re_dfa_t *dfa; + int node; + re_node_set *dest_nodes; + const re_node_set *candidates; +{ + int ecl_idx; + reg_errcode_t err; + re_node_set *inv_eclosure = dfa->inveclosures + node; + re_node_set except_nodes; + re_node_set_init_empty (&except_nodes); + for (ecl_idx = 0; ecl_idx < inv_eclosure->nelem; ++ecl_idx) + { + int cur_node = inv_eclosure->elems[ecl_idx]; + if (cur_node == node) + continue; + if (IS_EPSILON_NODE (dfa->nodes[cur_node].type)) + { + int edst1 = dfa->edests[cur_node].elems[0]; + int edst2 = ((dfa->edests[cur_node].nelem > 1) + ? dfa->edests[cur_node].elems[1] : -1); + if ((!re_node_set_contains (inv_eclosure, edst1) + && re_node_set_contains (dest_nodes, edst1)) + || (edst2 > 0 + && !re_node_set_contains (inv_eclosure, edst2) + && re_node_set_contains (dest_nodes, edst2))) + { + err = re_node_set_add_intersect (&except_nodes, candidates, + dfa->inveclosures + cur_node); + if (BE (err != REG_NOERROR, 0)) + { + re_node_set_free (&except_nodes); + return err; + } + } + } + } + for (ecl_idx = 0; ecl_idx < inv_eclosure->nelem; ++ecl_idx) + { + int cur_node = inv_eclosure->elems[ecl_idx]; + if (!re_node_set_contains (&except_nodes, cur_node)) + { + int idx = re_node_set_contains (dest_nodes, cur_node) - 1; + re_node_set_remove_at (dest_nodes, idx); + } + } + re_node_set_free (&except_nodes); + return REG_NOERROR; +} + +static int +check_dst_limits (dfa, limits, mctx, dst_node, dst_idx, src_node, src_idx) + re_dfa_t *dfa; + re_node_set *limits; + re_match_context_t *mctx; + int dst_node, dst_idx, src_node, src_idx; +{ + int lim_idx, src_pos, dst_pos; + + for (lim_idx = 0; lim_idx < limits->nelem; ++lim_idx) + { + int subexp_idx; + struct re_backref_cache_entry *ent; + ent = mctx->bkref_ents + limits->elems[lim_idx]; + subexp_idx = dfa->nodes[ent->node].opr.idx - 1; + + dst_pos = check_dst_limits_calc_pos (dfa, mctx, limits->elems[lim_idx], + dfa->eclosures + dst_node, + subexp_idx, dst_node, dst_idx); + src_pos = check_dst_limits_calc_pos (dfa, mctx, limits->elems[lim_idx], + dfa->eclosures + src_node, + subexp_idx, src_node, src_idx); + + /* In case of: + <src> <dst> ( <subexp> ) + ( <subexp> ) <src> <dst> + ( <subexp1> <src> <subexp2> <dst> <subexp3> ) */ + if (src_pos == dst_pos) + continue; /* This is unrelated limitation. */ + else + return 1; + } + return 0; +} + +static int +check_dst_limits_calc_pos (dfa, mctx, limit, eclosures, subexp_idx, node, + str_idx) + re_dfa_t *dfa; + re_match_context_t *mctx; + re_node_set *eclosures; + int limit, subexp_idx, node, str_idx; +{ + struct re_backref_cache_entry *lim = mctx->bkref_ents + limit; + int pos = (str_idx < lim->subexp_from ? -1 + : (lim->subexp_to < str_idx ? 1 : 0)); + if (pos == 0 + && (str_idx == lim->subexp_from || str_idx == lim->subexp_to)) + { + int node_idx; + for (node_idx = 0; node_idx < eclosures->nelem; ++node_idx) + { + int node = eclosures->elems[node_idx]; + re_token_type_t type= dfa->nodes[node].type; + if (type == OP_BACK_REF) + { + int bi = search_cur_bkref_entry (mctx, str_idx); + for (; bi < mctx->nbkref_ents; ++bi) + { + struct re_backref_cache_entry *ent = mctx->bkref_ents + bi; + if (ent->str_idx > str_idx) + break; + if (ent->node == node && ent->subexp_from == ent->subexp_to) + { + int cpos, dst; + dst = dfa->edests[node].elems[0]; + cpos = check_dst_limits_calc_pos (dfa, mctx, limit, + dfa->eclosures + dst, + subexp_idx, dst, + str_idx); + if ((str_idx == lim->subexp_from && cpos == -1) + || (str_idx == lim->subexp_to && cpos == 0)) + return cpos; + } + } + } + if (type == OP_OPEN_SUBEXP && subexp_idx == dfa->nodes[node].opr.idx + && str_idx == lim->subexp_from) + { + pos = -1; + break; + } + if (type == OP_CLOSE_SUBEXP && subexp_idx == dfa->nodes[node].opr.idx + && str_idx == lim->subexp_to) + break; + } + if (node_idx == eclosures->nelem && str_idx == lim->subexp_to) + pos = 1; + } + return pos; +} + +/* Check the limitations of sub expressions LIMITS, and remove the nodes + which are against limitations from DEST_NODES. */ + +static reg_errcode_t +check_subexp_limits (dfa, dest_nodes, candidates, limits, bkref_ents, str_idx) + re_dfa_t *dfa; + re_node_set *dest_nodes; + const re_node_set *candidates; + re_node_set *limits; + struct re_backref_cache_entry *bkref_ents; + int str_idx; +{ + reg_errcode_t err; + int node_idx, lim_idx; + + for (lim_idx = 0; lim_idx < limits->nelem; ++lim_idx) + { + int subexp_idx; + struct re_backref_cache_entry *ent; + ent = bkref_ents + limits->elems[lim_idx]; + + if (str_idx <= ent->subexp_from || ent->str_idx < str_idx) + continue; /* This is unrelated limitation. */ + + subexp_idx = dfa->nodes[ent->node].opr.idx - 1; + if (ent->subexp_to == str_idx) + { + int ops_node = -1; + int cls_node = -1; + for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx) + { + int node = dest_nodes->elems[node_idx]; + re_token_type_t type= dfa->nodes[node].type; + if (type == OP_OPEN_SUBEXP + && subexp_idx == dfa->nodes[node].opr.idx) + ops_node = node; + else if (type == OP_CLOSE_SUBEXP + && subexp_idx == dfa->nodes[node].opr.idx) + cls_node = node; + } + + /* Check the limitation of the open subexpression. */ + /* Note that (ent->subexp_to = str_idx != ent->subexp_from). */ + if (ops_node >= 0) + { + err = sub_epsilon_src_nodes(dfa, ops_node, dest_nodes, + candidates); + if (BE (err != REG_NOERROR, 0)) + return err; + } + /* Check the limitation of the close subexpression. */ + for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx) + { + int node = dest_nodes->elems[node_idx]; + if (!re_node_set_contains (dfa->inveclosures + node, cls_node) + && !re_node_set_contains (dfa->eclosures + node, cls_node)) + { + /* It is against this limitation. + Remove it form the current sifted state. */ + err = sub_epsilon_src_nodes(dfa, node, dest_nodes, + candidates); + if (BE (err != REG_NOERROR, 0)) + return err; + --node_idx; + } + } + } + else /* (ent->subexp_to != str_idx) */ + { + for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx) + { + int node = dest_nodes->elems[node_idx]; + re_token_type_t type= dfa->nodes[node].type; + if (type == OP_CLOSE_SUBEXP || type == OP_OPEN_SUBEXP) + { + if (subexp_idx != dfa->nodes[node].opr.idx) + continue; + if ((type == OP_CLOSE_SUBEXP && ent->subexp_to != str_idx) + || (type == OP_OPEN_SUBEXP)) + { + /* It is against this limitation. + Remove it form the current sifted state. */ + err = sub_epsilon_src_nodes(dfa, node, dest_nodes, + candidates); + if (BE (err != REG_NOERROR, 0)) + return err; + } + } + } + } + } + return REG_NOERROR; +} + +static reg_errcode_t +sift_states_bkref (preg, mctx, sctx, str_idx, dest_nodes) + const regex_t *preg; + re_match_context_t *mctx; + re_sift_context_t *sctx; + int str_idx; + re_node_set *dest_nodes; +{ + reg_errcode_t err; + re_dfa_t *dfa = (re_dfa_t *)preg->buffer; + int node_idx, node; + re_sift_context_t local_sctx; + const re_node_set *candidates; + candidates = ((mctx->state_log[str_idx] == NULL) ? &empty_set + : &mctx->state_log[str_idx]->nodes); + local_sctx.sifted_states = NULL; /* Mark that it hasn't been initialized. */ + + for (node_idx = 0; node_idx < candidates->nelem; ++node_idx) + { + int cur_bkref_idx = re_string_cur_idx (mctx->input); + re_token_type_t type; + node = candidates->elems[node_idx]; + type = dfa->nodes[node].type; + if (node == sctx->cur_bkref && str_idx == cur_bkref_idx) + continue; + /* Avoid infinite loop for the REs like "()\1+". */ + if (node == sctx->last_node && str_idx == sctx->last_str_idx) + continue; + if (type == OP_BACK_REF) + { + int enabled_idx = search_cur_bkref_entry (mctx, str_idx); + for (; enabled_idx < mctx->nbkref_ents; ++enabled_idx) + { + int disabled_idx, subexp_len, to_idx, dst_node; + struct re_backref_cache_entry *entry; + entry = mctx->bkref_ents + enabled_idx; + if (entry->str_idx > str_idx) + break; + if (entry->node != node) + continue; + subexp_len = entry->subexp_to - entry->subexp_from; + to_idx = str_idx + subexp_len; + dst_node = (subexp_len ? dfa->nexts[node] + : dfa->edests[node].elems[0]); + + if (to_idx > sctx->last_str_idx + || sctx->sifted_states[to_idx] == NULL + || !STATE_NODE_CONTAINS (sctx->sifted_states[to_idx], + dst_node) + || check_dst_limits (dfa, &sctx->limits, mctx, node, + str_idx, dst_node, to_idx)) + continue; + { + re_dfastate_t *cur_state; + entry->flag = 0; + for (disabled_idx = enabled_idx + 1; + disabled_idx < mctx->nbkref_ents; ++disabled_idx) + { + struct re_backref_cache_entry *entry2; + entry2 = mctx->bkref_ents + disabled_idx; + if (entry2->str_idx > str_idx) + break; + entry2->flag = (entry2->node == node) ? 1 : entry2->flag; + } + + if (local_sctx.sifted_states == NULL) + { + local_sctx = *sctx; + err = re_node_set_init_copy (&local_sctx.limits, + &sctx->limits); + if (BE (err != REG_NOERROR, 0)) + goto free_return; + } + local_sctx.last_node = node; + local_sctx.last_str_idx = str_idx; + err = re_node_set_insert (&local_sctx.limits, enabled_idx); + if (BE (err < 0, 0)) + { + err = REG_ESPACE; + goto free_return; + } + cur_state = local_sctx.sifted_states[str_idx]; + err = sift_states_backward (preg, mctx, &local_sctx); + if (BE (err != REG_NOERROR, 0)) + goto free_return; + if (sctx->limited_states != NULL) + { + err = merge_state_array (dfa, sctx->limited_states, + local_sctx.sifted_states, + str_idx + 1); + if (BE (err != REG_NOERROR, 0)) + goto free_return; + } + local_sctx.sifted_states[str_idx] = cur_state; + re_node_set_remove (&local_sctx.limits, enabled_idx); + /* We must not use the variable entry here, since + mctx->bkref_ents might be realloced. */ + mctx->bkref_ents[enabled_idx].flag = 1; + } + } + enabled_idx = search_cur_bkref_entry (mctx, str_idx); + for (; enabled_idx < mctx->nbkref_ents; ++enabled_idx) + { + struct re_backref_cache_entry *entry; + entry = mctx->bkref_ents + enabled_idx; + if (entry->str_idx > str_idx) + break; + if (entry->node == node) + entry->flag = 0; + } + } + } + err = REG_NOERROR; + free_return: + if (local_sctx.sifted_states != NULL) + { + re_node_set_free (&local_sctx.limits); + } + + return err; +} + + +#ifdef RE_ENABLE_I18N +static int +sift_states_iter_mb (preg, mctx, sctx, node_idx, str_idx, max_str_idx) + const regex_t *preg; + const re_match_context_t *mctx; + re_sift_context_t *sctx; + int node_idx, str_idx, max_str_idx; +{ + re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + int naccepted; + /* Check the node can accept `multi byte'. */ + naccepted = check_node_accept_bytes (preg, node_idx, mctx->input, str_idx); + if (naccepted > 0 && str_idx + naccepted <= max_str_idx && + !STATE_NODE_CONTAINS (sctx->sifted_states[str_idx + naccepted], + dfa->nexts[node_idx])) + /* The node can't accept the `multi byte', or the + destination was already throwed away, then the node + could't accept the current input `multi byte'. */ + naccepted = 0; + /* Otherwise, it is sure that the node could accept + `naccepted' bytes input. */ + return naccepted; +} +#endif /* RE_ENABLE_I18N */ + + +/* Functions for state transition. */ + +/* Return the next state to which the current state STATE will transit by + accepting the current input byte, and update STATE_LOG if necessary. + If STATE can accept a multibyte char/collating element/back reference + update the destination of STATE_LOG. */ + +static re_dfastate_t * +transit_state (err, preg, mctx, state, fl_search) + reg_errcode_t *err; + const regex_t *preg; + re_match_context_t *mctx; + re_dfastate_t *state; + int fl_search; +{ + re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + re_dfastate_t **trtable, *next_state; + unsigned char ch; + int cur_idx; + + if (re_string_cur_idx (mctx->input) + 1 >= mctx->input->bufs_len + || (re_string_cur_idx (mctx->input) + 1 >= mctx->input->valid_len + && mctx->input->valid_len < mctx->input->len)) + { + *err = extend_buffers (mctx); + if (BE (*err != REG_NOERROR, 0)) + return NULL; + } + + *err = REG_NOERROR; + if (state == NULL) + { + next_state = state; + re_string_skip_bytes (mctx->input, 1); + } + else + { +#ifdef RE_ENABLE_I18N + /* If the current state can accept multibyte. */ + if (state->accept_mb) + { + *err = transit_state_mb (preg, state, mctx); + if (BE (*err != REG_NOERROR, 0)) + return NULL; + } +#endif /* RE_ENABLE_I18N */ + + /* Then decide the next state with the single byte. */ + if (1) + { + /* Use transition table */ + ch = re_string_fetch_byte (mctx->input); + trtable = fl_search ? state->trtable_search : state->trtable; + if (trtable == NULL) + { + trtable = build_trtable (preg, state, fl_search); + if (fl_search) + state->trtable_search = trtable; + else + state->trtable = trtable; + } + next_state = trtable[ch]; + } + else + { + /* don't use transition table */ + next_state = transit_state_sb (err, preg, state, fl_search, mctx); + if (BE (next_state == NULL && err != REG_NOERROR, 0)) + return NULL; + } + } + + cur_idx = re_string_cur_idx (mctx->input); + /* Update the state_log if we need. */ + if (mctx->state_log != NULL) + { + if (cur_idx > mctx->state_log_top) + { + mctx->state_log[cur_idx] = next_state; + mctx->state_log_top = cur_idx; + } + else if (mctx->state_log[cur_idx] == 0) + { + mctx->state_log[cur_idx] = next_state; + } + else + { + re_dfastate_t *pstate; + unsigned int context; + re_node_set next_nodes, *log_nodes, *table_nodes = NULL; + /* If (state_log[cur_idx] != 0), it implies that cur_idx is + the destination of a multibyte char/collating element/ + back reference. Then the next state is the union set of + these destinations and the results of the transition table. */ + pstate = mctx->state_log[cur_idx]; + log_nodes = pstate->entrance_nodes; + if (next_state != NULL) + { + table_nodes = next_state->entrance_nodes; + *err = re_node_set_init_union (&next_nodes, table_nodes, + log_nodes); + if (BE (*err != REG_NOERROR, 0)) + return NULL; + } + else + next_nodes = *log_nodes; + /* Note: We already add the nodes of the initial state, + then we don't need to add them here. */ + + context = re_string_context_at (mctx->input, + re_string_cur_idx (mctx->input) - 1, + mctx->eflags, preg->newline_anchor); + next_state = mctx->state_log[cur_idx] + = re_acquire_state_context (err, dfa, &next_nodes, context); + /* We don't need to check errors here, since the return value of + this function is next_state and ERR is already set. */ + + if (table_nodes != NULL) + re_node_set_free (&next_nodes); + } + } + + /* Check OP_OPEN_SUBEXP in the current state in case that we use them + later. We must check them here, since the back references in the + next state might use them. */ + if (dfa->nbackref && next_state/* && fl_process_bkref */) + { + *err = check_subexp_matching_top (dfa, mctx, &next_state->nodes, + cur_idx); + if (BE (*err != REG_NOERROR, 0)) + return NULL; + } + + /* If the next state has back references. */ + if (next_state != NULL && next_state->has_backref) + { + *err = transit_state_bkref (preg, &next_state->nodes, mctx); + if (BE (*err != REG_NOERROR, 0)) + return NULL; + next_state = mctx->state_log[cur_idx]; + } + return next_state; +} + +/* Helper functions for transit_state. */ + +/* From the node set CUR_NODES, pick up the nodes whose types are + OP_OPEN_SUBEXP and which have corresponding back references in the regular + expression. And register them to use them later for evaluating the + correspoding back references. */ + +static reg_errcode_t +check_subexp_matching_top (dfa, mctx, cur_nodes, str_idx) + re_dfa_t *dfa; + re_match_context_t *mctx; + re_node_set *cur_nodes; + int str_idx; +{ + int node_idx; + reg_errcode_t err; + + /* TODO: This isn't efficient. + Because there might be more than one nodes whose types are + OP_OPEN_SUBEXP and whose index is SUBEXP_IDX, we must check all + nodes. + E.g. RE: (a){2} */ + for (node_idx = 0; node_idx < cur_nodes->nelem; ++node_idx) + { + int node = cur_nodes->elems[node_idx]; + if (dfa->nodes[node].type == OP_OPEN_SUBEXP + && dfa->used_bkref_map & (1 << dfa->nodes[node].opr.idx)) + { + err = match_ctx_add_subtop (mctx, node, str_idx); + if (BE (err != REG_NOERROR, 0)) + return err; + } + } + return REG_NOERROR; +} + +/* Return the next state to which the current state STATE will transit by + accepting the current input byte. */ + +static re_dfastate_t * +transit_state_sb (err, preg, state, fl_search, mctx) + reg_errcode_t *err; + const regex_t *preg; + re_dfastate_t *state; + int fl_search; + re_match_context_t *mctx; +{ + re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + re_node_set next_nodes; + re_dfastate_t *next_state; + int node_cnt, cur_str_idx = re_string_cur_idx (mctx->input); + unsigned int context; + + *err = re_node_set_alloc (&next_nodes, state->nodes.nelem + 1); + if (BE (*err != REG_NOERROR, 0)) + return NULL; + for (node_cnt = 0; node_cnt < state->nodes.nelem; ++node_cnt) + { + int cur_node = state->nodes.elems[node_cnt]; + if (check_node_accept (preg, dfa->nodes + cur_node, mctx, cur_str_idx)) + { + *err = re_node_set_merge (&next_nodes, + dfa->eclosures + dfa->nexts[cur_node]); + if (BE (*err != REG_NOERROR, 0)) + { + re_node_set_free (&next_nodes); + return NULL; + } + } + } + if (fl_search) + { +#ifdef RE_ENABLE_I18N + int not_initial = 0; + if (re_mb_cur_max > 1) + for (node_cnt = 0; node_cnt < next_nodes.nelem; ++node_cnt) + if (dfa->nodes[next_nodes.elems[node_cnt]].type == CHARACTER) + { + not_initial = dfa->nodes[next_nodes.elems[node_cnt]].mb_partial; + break; + } + if (!not_initial) +#endif + { + *err = re_node_set_merge (&next_nodes, + dfa->init_state->entrance_nodes); + if (BE (*err != REG_NOERROR, 0)) + { + re_node_set_free (&next_nodes); + return NULL; + } + } + } + context = re_string_context_at (mctx->input, cur_str_idx, mctx->eflags, + preg->newline_anchor); + next_state = re_acquire_state_context (err, dfa, &next_nodes, context); + /* We don't need to check errors here, since the return value of + this function is next_state and ERR is already set. */ + + re_node_set_free (&next_nodes); + re_string_skip_bytes (mctx->input, 1); + return next_state; +} + +#ifdef RE_ENABLE_I18N +static reg_errcode_t +transit_state_mb (preg, pstate, mctx) + const regex_t *preg; + re_dfastate_t *pstate; + re_match_context_t *mctx; +{ + reg_errcode_t err; + re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + int i; + + for (i = 0; i < pstate->nodes.nelem; ++i) + { + re_node_set dest_nodes, *new_nodes; + int cur_node_idx = pstate->nodes.elems[i]; + int naccepted = 0, dest_idx; + unsigned int context; + re_dfastate_t *dest_state; + + if (dfa->nodes[cur_node_idx].constraint) + { + context = re_string_context_at (mctx->input, + re_string_cur_idx (mctx->input), + mctx->eflags, preg->newline_anchor); + if (NOT_SATISFY_NEXT_CONSTRAINT (dfa->nodes[cur_node_idx].constraint, + context)) + continue; + } + + /* How many bytes the node can accepts? */ + if (ACCEPT_MB_NODE (dfa->nodes[cur_node_idx].type)) + naccepted = check_node_accept_bytes (preg, cur_node_idx, mctx->input, + re_string_cur_idx (mctx->input)); + if (naccepted == 0) + continue; + + /* The node can accepts `naccepted' bytes. */ + dest_idx = re_string_cur_idx (mctx->input) + naccepted; + mctx->max_mb_elem_len = ((mctx->max_mb_elem_len < naccepted) ? naccepted + : mctx->max_mb_elem_len); + err = clean_state_log_if_need (mctx, dest_idx); + if (BE (err != REG_NOERROR, 0)) + return err; +#ifdef DEBUG + assert (dfa->nexts[cur_node_idx] != -1); +#endif + /* `cur_node_idx' may point the entity of the OP_CONTEXT_NODE, + then we use pstate->nodes.elems[i] instead. */ + new_nodes = dfa->eclosures + dfa->nexts[pstate->nodes.elems[i]]; + + dest_state = mctx->state_log[dest_idx]; + if (dest_state == NULL) + dest_nodes = *new_nodes; + else + { + err = re_node_set_init_union (&dest_nodes, + dest_state->entrance_nodes, new_nodes); + if (BE (err != REG_NOERROR, 0)) + return err; + } + context = re_string_context_at (mctx->input, dest_idx - 1, mctx->eflags, + preg->newline_anchor); + mctx->state_log[dest_idx] + = re_acquire_state_context (&err, dfa, &dest_nodes, context); + if (dest_state != NULL) + re_node_set_free (&dest_nodes); + if (BE (mctx->state_log[dest_idx] == NULL && err != REG_NOERROR, 0)) + return err; + } + return REG_NOERROR; +} +#endif /* RE_ENABLE_I18N */ + +static reg_errcode_t +transit_state_bkref (preg, nodes, mctx) + const regex_t *preg; + re_node_set *nodes; + re_match_context_t *mctx; +{ + reg_errcode_t err; + re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + int i; + int cur_str_idx = re_string_cur_idx (mctx->input); + + for (i = 0; i < nodes->nelem; ++i) + { + int dest_str_idx, prev_nelem, bkc_idx; + int node_idx = nodes->elems[i]; + unsigned int context; + re_token_t *node = dfa->nodes + node_idx; + re_node_set *new_dest_nodes; + + /* Check whether `node' is a backreference or not. */ + if (node->type != OP_BACK_REF) + continue; + + if (node->constraint) + { + context = re_string_context_at (mctx->input, cur_str_idx, + mctx->eflags, preg->newline_anchor); + if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context)) + continue; + } + + /* `node' is a backreference. + Check the substring which the substring matched. */ + bkc_idx = mctx->nbkref_ents; + err = get_subexp (preg, mctx, node_idx, cur_str_idx); + if (BE (err != REG_NOERROR, 0)) + goto free_return; + + /* And add the epsilon closures (which is `new_dest_nodes') of + the backreference to appropriate state_log. */ +#ifdef DEBUG + assert (dfa->nexts[node_idx] != -1); +#endif + for (; bkc_idx < mctx->nbkref_ents; ++bkc_idx) + { + int subexp_len; + re_dfastate_t *dest_state; + struct re_backref_cache_entry *bkref_ent; + bkref_ent = mctx->bkref_ents + bkc_idx; + if (bkref_ent->node != node_idx || bkref_ent->str_idx != cur_str_idx) + continue; + subexp_len = bkref_ent->subexp_to - bkref_ent->subexp_from; + new_dest_nodes = (subexp_len == 0 + ? dfa->eclosures + dfa->edests[node_idx].elems[0] + : dfa->eclosures + dfa->nexts[node_idx]); + dest_str_idx = (cur_str_idx + bkref_ent->subexp_to + - bkref_ent->subexp_from); + context = re_string_context_at (mctx->input, dest_str_idx - 1, + mctx->eflags, preg->newline_anchor); + dest_state = mctx->state_log[dest_str_idx]; + prev_nelem = ((mctx->state_log[cur_str_idx] == NULL) ? 0 + : mctx->state_log[cur_str_idx]->nodes.nelem); + /* Add `new_dest_node' to state_log. */ + if (dest_state == NULL) + { + mctx->state_log[dest_str_idx] + = re_acquire_state_context (&err, dfa, new_dest_nodes, + context); + if (BE (mctx->state_log[dest_str_idx] == NULL + && err != REG_NOERROR, 0)) + goto free_return; + } + else + { + re_node_set dest_nodes; + err = re_node_set_init_union (&dest_nodes, + dest_state->entrance_nodes, + new_dest_nodes); + if (BE (err != REG_NOERROR, 0)) + { + re_node_set_free (&dest_nodes); + goto free_return; + } + mctx->state_log[dest_str_idx] + = re_acquire_state_context (&err, dfa, &dest_nodes, context); + re_node_set_free (&dest_nodes); + if (BE (mctx->state_log[dest_str_idx] == NULL + && err != REG_NOERROR, 0)) + goto free_return; + } + /* We need to check recursively if the backreference can epsilon + transit. */ + if (subexp_len == 0 + && mctx->state_log[cur_str_idx]->nodes.nelem > prev_nelem) + { + err = check_subexp_matching_top (dfa, mctx, new_dest_nodes, + cur_str_idx); + if (BE (err != REG_NOERROR, 0)) + goto free_return; + err = transit_state_bkref (preg, new_dest_nodes, mctx); + if (BE (err != REG_NOERROR, 0)) + goto free_return; + } + } + } + err = REG_NOERROR; + free_return: + return err; +} + +/* Enumerate all the candidates which the backreference BKREF_NODE can match + at BKREF_STR_IDX, and register them by match_ctx_add_entry(). + Note that we might collect inappropriate candidates here. + However, the cost of checking them strictly here is too high, then we + delay these checking for prune_impossible_nodes(). */ + +static reg_errcode_t +get_subexp (preg, mctx, bkref_node, bkref_str_idx) + const regex_t *preg; + re_match_context_t *mctx; + int bkref_node, bkref_str_idx; +{ + int subexp_num, sub_top_idx; + re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + char *buf = (char *) re_string_get_buffer (mctx->input); + /* Return if we have already checked BKREF_NODE at BKREF_STR_IDX. */ + int cache_idx = search_cur_bkref_entry (mctx, bkref_str_idx); + for (; cache_idx < mctx->nbkref_ents; ++cache_idx) + { + struct re_backref_cache_entry *entry = mctx->bkref_ents + cache_idx; + if (entry->str_idx > bkref_str_idx) + break; + if (entry->node == bkref_node) + return REG_NOERROR; /* We already checked it. */ + } + subexp_num = dfa->nodes[bkref_node].opr.idx - 1; + + /* For each sub expression */ + for (sub_top_idx = 0; sub_top_idx < mctx->nsub_tops; ++sub_top_idx) + { + reg_errcode_t err; + re_sub_match_top_t *sub_top = mctx->sub_tops[sub_top_idx]; + re_sub_match_last_t *sub_last; + int sub_last_idx, sl_str; + char *bkref_str; + + if (dfa->nodes[sub_top->node].opr.idx != subexp_num) + continue; /* It isn't related. */ + + sl_str = sub_top->str_idx; + bkref_str = buf + bkref_str_idx; + /* At first, check the last node of sub expressions we already + evaluated. */ + for (sub_last_idx = 0; sub_last_idx < sub_top->nlasts; ++sub_last_idx) + { + int sl_str_diff; + sub_last = sub_top->lasts[sub_last_idx]; + sl_str_diff = sub_last->str_idx - sl_str; + /* The matched string by the sub expression match with the substring + at the back reference? */ + if (sl_str_diff > 0 + && memcmp (bkref_str, buf + sl_str, sl_str_diff) != 0) + break; /* We don't need to search this sub expression any more. */ + bkref_str += sl_str_diff; + sl_str += sl_str_diff; + err = get_subexp_sub (preg, mctx, sub_top, sub_last, bkref_node, + bkref_str_idx); + if (err == REG_NOMATCH) + continue; + if (BE (err != REG_NOERROR, 0)) + return err; + } + if (sub_last_idx < sub_top->nlasts) + continue; + if (sub_last_idx > 0) + ++sl_str; + /* Then, search for the other last nodes of the sub expression. */ + for (; sl_str <= bkref_str_idx; ++sl_str) + { + int cls_node, sl_str_off; + re_node_set *nodes; + sl_str_off = sl_str - sub_top->str_idx; + /* The matched string by the sub expression match with the substring + at the back reference? */ + if (sl_str_off > 0 + && memcmp (bkref_str++, buf + sl_str - 1, 1) != 0) + break; /* We don't need to search this sub expression any more. */ + if (mctx->state_log[sl_str] == NULL) + continue; + /* Does this state have a ')' of the sub expression? */ + nodes = &mctx->state_log[sl_str]->nodes; + cls_node = find_subexp_node (dfa, nodes, subexp_num, 0); + if (cls_node == -1) + continue; /* No. */ + if (sub_top->path == NULL) + { + sub_top->path = calloc (sizeof (state_array_t), + sl_str - sub_top->str_idx + 1); + if (sub_top->path == NULL) + return REG_ESPACE; + } + /* Can the OP_OPEN_SUBEXP node arrive the OP_CLOSE_SUBEXP node + in the current context? */ + err = check_arrival (preg, mctx, sub_top->path, sub_top->node, + sub_top->str_idx, cls_node, sl_str, 0); + if (err == REG_NOMATCH) + continue; + if (BE (err != REG_NOERROR, 0)) + return err; + sub_last = match_ctx_add_sublast (sub_top, cls_node, sl_str); + if (BE (sub_last == NULL, 0)) + return REG_ESPACE; + err = get_subexp_sub (preg, mctx, sub_top, sub_last, bkref_node, + bkref_str_idx); + if (err == REG_NOMATCH) + continue; + } + } + return REG_NOERROR; +} + +/* Helper functions for get_subexp(). */ + +/* Check SUB_LAST can arrive to the back reference BKREF_NODE at BKREF_STR. + If it can arrive, register the sub expression expressed with SUB_TOP + and SUB_LAST. */ + +static reg_errcode_t +get_subexp_sub (preg, mctx, sub_top, sub_last, bkref_node, bkref_str) + const regex_t *preg; + re_match_context_t *mctx; + re_sub_match_top_t *sub_top; + re_sub_match_last_t *sub_last; + int bkref_node, bkref_str; +{ + reg_errcode_t err; + int to_idx; + /* Can the subexpression arrive the back reference? */ + err = check_arrival (preg, mctx, &sub_last->path, sub_last->node, + sub_last->str_idx, bkref_node, bkref_str, 1); + if (err != REG_NOERROR) + return err; + err = match_ctx_add_entry (mctx, bkref_node, bkref_str, sub_top->str_idx, + sub_last->str_idx); + if (BE (err != REG_NOERROR, 0)) + return err; + to_idx = bkref_str + sub_last->str_idx - sub_top->str_idx; + clean_state_log_if_need (mctx, to_idx); + return REG_NOERROR; +} + +/* Find the first node which is '(' or ')' and whose index is SUBEXP_IDX. + Search '(' if FL_OPEN, or search ')' otherwise. + TODO: This function isn't efficient... + Because there might be more than one nodes whose types are + OP_OPEN_SUBEXP and whose index is SUBEXP_IDX, we must check all + nodes. + E.g. RE: (a){2} */ + +static int +find_subexp_node (dfa, nodes, subexp_idx, fl_open) + re_dfa_t *dfa; + re_node_set *nodes; + int subexp_idx, fl_open; +{ + int cls_idx; + for (cls_idx = 0; cls_idx < nodes->nelem; ++cls_idx) + { + int cls_node = nodes->elems[cls_idx]; + re_token_t *node = dfa->nodes + cls_node; + if (((fl_open && node->type == OP_OPEN_SUBEXP) + || (!fl_open && node->type == OP_CLOSE_SUBEXP)) + && node->opr.idx == subexp_idx) + return cls_node; + } + return -1; +} + +/* Check whether the node TOP_NODE at TOP_STR can arrive to the node + LAST_NODE at LAST_STR. We record the path onto PATH since it will be + heavily reused. + Return REG_NOERROR if it can arrive, or REG_NOMATCH otherwise. */ + +static reg_errcode_t +check_arrival (preg, mctx, path, top_node, top_str, last_node, last_str, + fl_open) + const regex_t *preg; + re_match_context_t *mctx; + state_array_t *path; + int top_node, top_str, last_node, last_str, fl_open; +{ + re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + reg_errcode_t err; + int subexp_num, backup_cur_idx, str_idx, null_cnt; + re_dfastate_t *cur_state = NULL; + re_node_set *cur_nodes, next_nodes; + re_dfastate_t **backup_state_log; + unsigned int context; + + subexp_num = dfa->nodes[top_node].opr.idx; + /* Extend the buffer if we need. */ + if (path->alloc < last_str + mctx->max_mb_elem_len + 1) + { + re_dfastate_t **new_array; + int old_alloc = path->alloc; + path->alloc += last_str + mctx->max_mb_elem_len + 1; + new_array = re_realloc (path->array, re_dfastate_t *, path->alloc); + if (new_array == NULL) + return REG_ESPACE; + path->array = new_array; + memset (new_array + old_alloc, '\0', + sizeof (re_dfastate_t *) * (path->alloc - old_alloc)); + } + + str_idx = path->next_idx == 0 ? top_str : path->next_idx; + + /* Temporary modify MCTX. */ + backup_state_log = mctx->state_log; + backup_cur_idx = mctx->input->cur_idx; + mctx->state_log = path->array; + mctx->input->cur_idx = str_idx; + + /* Setup initial node set. */ + context = re_string_context_at (mctx->input, str_idx - 1, mctx->eflags, + preg->newline_anchor); + if (str_idx == top_str) + { + err = re_node_set_init_1 (&next_nodes, top_node); + if (BE (err != REG_NOERROR, 0)) + return err; + err = check_arrival_expand_ecl (dfa, &next_nodes, subexp_num, fl_open); + if (BE (err != REG_NOERROR, 0)) + { + re_node_set_free (&next_nodes); + return err; + } + } + else + { + cur_state = mctx->state_log[str_idx]; + if (cur_state && cur_state->has_backref) + { + err = re_node_set_init_copy (&next_nodes, &cur_state->nodes); + if (BE ( err != REG_NOERROR, 0)) + return err; + } + else + re_node_set_init_empty (&next_nodes); + } + if (str_idx == top_str || (cur_state && cur_state->has_backref)) + { + if (next_nodes.nelem) + { + err = expand_bkref_cache (preg, mctx, &next_nodes, str_idx, last_str, + subexp_num, fl_open); + if (BE ( err != REG_NOERROR, 0)) + { + re_node_set_free (&next_nodes); + return err; + } + } + cur_state = re_acquire_state_context (&err, dfa, &next_nodes, context); + if (BE (cur_state == NULL && err != REG_NOERROR, 0)) + { + re_node_set_free (&next_nodes); + return err; + } + mctx->state_log[str_idx] = cur_state; + } + + for (null_cnt = 0; str_idx < last_str && null_cnt <= mctx->max_mb_elem_len;) + { + re_node_set_empty (&next_nodes); + if (mctx->state_log[str_idx + 1]) + { + err = re_node_set_merge (&next_nodes, + &mctx->state_log[str_idx + 1]->nodes); + if (BE (err != REG_NOERROR, 0)) + { + re_node_set_free (&next_nodes); + return err; + } + } + if (cur_state) + { + err = check_arrival_add_next_nodes(preg, dfa, mctx, str_idx, + &cur_state->nodes, &next_nodes); + if (BE (err != REG_NOERROR, 0)) + { + re_node_set_free (&next_nodes); + return err; + } + } + ++str_idx; + if (next_nodes.nelem) + { + err = check_arrival_expand_ecl (dfa, &next_nodes, subexp_num, + fl_open); + if (BE (err != REG_NOERROR, 0)) + { + re_node_set_free (&next_nodes); + return err; + } + err = expand_bkref_cache (preg, mctx, &next_nodes, str_idx, last_str, + subexp_num, fl_open); + if (BE ( err != REG_NOERROR, 0)) + { + re_node_set_free (&next_nodes); + return err; + } + } + context = re_string_context_at (mctx->input, str_idx - 1, mctx->eflags, + preg->newline_anchor); + cur_state = re_acquire_state_context (&err, dfa, &next_nodes, context); + if (BE (cur_state == NULL && err != REG_NOERROR, 0)) + { + re_node_set_free (&next_nodes); + return err; + } + mctx->state_log[str_idx] = cur_state; + null_cnt = cur_state == NULL ? null_cnt + 1 : 0; + } + re_node_set_free (&next_nodes); + cur_nodes = (mctx->state_log[last_str] == NULL ? NULL + : &mctx->state_log[last_str]->nodes); + path->next_idx = str_idx; + + /* Fix MCTX. */ + mctx->state_log = backup_state_log; + mctx->input->cur_idx = backup_cur_idx; + + if (cur_nodes == NULL) + return REG_NOMATCH; + /* Then check the current node set has the node LAST_NODE. */ + return (re_node_set_contains (cur_nodes, last_node) + || re_node_set_contains (cur_nodes, last_node) ? REG_NOERROR + : REG_NOMATCH); +} + +/* Helper functions for check_arrival. */ + +/* Calculate the destination nodes of CUR_NODES at STR_IDX, and append them + to NEXT_NODES. + TODO: This function is similar to the functions transit_state*(), + however this function has many additional works. + Can't we unify them? */ + +static reg_errcode_t +check_arrival_add_next_nodes (preg, dfa, mctx, str_idx, cur_nodes, next_nodes) + const regex_t *preg; + re_dfa_t *dfa; + re_match_context_t *mctx; + int str_idx; + re_node_set *cur_nodes, *next_nodes; +{ + int cur_idx; + reg_errcode_t err; + re_node_set union_set; + re_node_set_init_empty (&union_set); + for (cur_idx = 0; cur_idx < cur_nodes->nelem; ++cur_idx) + { + int naccepted = 0; + int cur_node = cur_nodes->elems[cur_idx]; + re_token_type_t type = dfa->nodes[cur_node].type; + if (IS_EPSILON_NODE(type)) + continue; +#ifdef RE_ENABLE_I18N + /* If the node may accept `multi byte'. */ + if (ACCEPT_MB_NODE (type)) + { + naccepted = check_node_accept_bytes (preg, cur_node, mctx->input, + str_idx); + if (naccepted > 1) + { + re_dfastate_t *dest_state; + int next_node = dfa->nexts[cur_node]; + int next_idx = str_idx + naccepted; + dest_state = mctx->state_log[next_idx]; + re_node_set_empty (&union_set); + if (dest_state) + { + err = re_node_set_merge (&union_set, &dest_state->nodes); + if (BE (err != REG_NOERROR, 0)) + { + re_node_set_free (&union_set); + return err; + } + err = re_node_set_insert (&union_set, next_node); + if (BE (err < 0, 0)) + { + re_node_set_free (&union_set); + return REG_ESPACE; + } + } + else + { + err = re_node_set_insert (&union_set, next_node); + if (BE (err < 0, 0)) + { + re_node_set_free (&union_set); + return REG_ESPACE; + } + } + mctx->state_log[next_idx] = re_acquire_state (&err, dfa, + &union_set); + if (BE (mctx->state_log[next_idx] == NULL + && err != REG_NOERROR, 0)) + { + re_node_set_free (&union_set); + return err; + } + } + } +#endif /* RE_ENABLE_I18N */ + if (naccepted + || check_node_accept (preg, dfa->nodes + cur_node, mctx, + str_idx)) + { + err = re_node_set_insert (next_nodes, dfa->nexts[cur_node]); + if (BE (err < 0, 0)) + { + re_node_set_free (&union_set); + return REG_ESPACE; + } + } + } + re_node_set_free (&union_set); + return REG_NOERROR; +} + +/* For all the nodes in CUR_NODES, add the epsilon closures of them to + CUR_NODES, however exclude the nodes which are: + - inside the sub expression whose number is EX_SUBEXP, if FL_OPEN. + - out of the sub expression whose number is EX_SUBEXP, if !FL_OPEN. +*/ + +static reg_errcode_t +check_arrival_expand_ecl (dfa, cur_nodes, ex_subexp, fl_open) + re_dfa_t *dfa; + re_node_set *cur_nodes; + int ex_subexp, fl_open; +{ + reg_errcode_t err; + int idx, outside_node; + re_node_set new_nodes; +#ifdef DEBUG + assert (cur_nodes->nelem); +#endif + err = re_node_set_alloc (&new_nodes, cur_nodes->nelem); + if (BE (err != REG_NOERROR, 0)) + return err; + /* Create a new node set NEW_NODES with the nodes which are epsilon + closures of the node in CUR_NODES. */ + + for (idx = 0; idx < cur_nodes->nelem; ++idx) + { + int cur_node = cur_nodes->elems[idx]; + re_node_set *eclosure = dfa->eclosures + cur_node; + outside_node = find_subexp_node (dfa, eclosure, ex_subexp, fl_open); + if (outside_node == -1) + { + /* There are no problematic nodes, just merge them. */ + err = re_node_set_merge (&new_nodes, eclosure); + if (BE (err != REG_NOERROR, 0)) + { + re_node_set_free (&new_nodes); + return err; + } + } + else + { + /* There are problematic nodes, re-calculate incrementally. */ + err = check_arrival_expand_ecl_sub (dfa, &new_nodes, cur_node, + ex_subexp, fl_open); + if (BE (err != REG_NOERROR, 0)) + { + re_node_set_free (&new_nodes); + return err; + } + } + } + re_node_set_free (cur_nodes); + *cur_nodes = new_nodes; + return REG_NOERROR; +} + +/* Helper function for check_arrival_expand_ecl. + Check incrementally the epsilon closure of TARGET, and if it isn't + problematic append it to DST_NODES. */ + +static reg_errcode_t +check_arrival_expand_ecl_sub (dfa, dst_nodes, target, ex_subexp, fl_open) + re_dfa_t *dfa; + int target, ex_subexp, fl_open; + re_node_set *dst_nodes; +{ + int cur_node, type; + for (cur_node = target; !re_node_set_contains (dst_nodes, cur_node);) + { + int err; + type = dfa->nodes[cur_node].type; + + if (((type == OP_OPEN_SUBEXP && fl_open) + || (type == OP_CLOSE_SUBEXP && !fl_open)) + && dfa->nodes[cur_node].opr.idx == ex_subexp) + { + if (!fl_open) + { + err = re_node_set_insert (dst_nodes, cur_node); + if (BE (err == -1, 0)) + return REG_ESPACE; + } + break; + } + err = re_node_set_insert (dst_nodes, cur_node); + if (BE (err == -1, 0)) + return REG_ESPACE; + if (dfa->edests[cur_node].nelem == 0) + break; + if (dfa->edests[cur_node].nelem == 2) + { + err = check_arrival_expand_ecl_sub (dfa, dst_nodes, + dfa->edests[cur_node].elems[1], + ex_subexp, fl_open); + if (BE (err != REG_NOERROR, 0)) + return err; + } + cur_node = dfa->edests[cur_node].elems[0]; + } + return REG_NOERROR; +} + + +/* For all the back references in the current state, calculate the + destination of the back references by the appropriate entry + in MCTX->BKREF_ENTS. */ + +static reg_errcode_t +expand_bkref_cache (preg, mctx, cur_nodes, cur_str, last_str, subexp_num, + fl_open) + const regex_t *preg; + re_match_context_t *mctx; + int cur_str, last_str, subexp_num, fl_open; + re_node_set *cur_nodes; +{ + reg_errcode_t err; + re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + int cache_idx, cache_idx_start; + /* The current state. */ + + cache_idx_start = search_cur_bkref_entry (mctx, cur_str); + for (cache_idx = cache_idx_start; cache_idx < mctx->nbkref_ents; ++cache_idx) + { + int to_idx, next_node; + struct re_backref_cache_entry *ent = mctx->bkref_ents + cache_idx; + if (ent->str_idx > cur_str) + break; + /* Is this entry ENT is appropriate? */ + if (!re_node_set_contains (cur_nodes, ent->node)) + continue; /* No. */ + + to_idx = cur_str + ent->subexp_to - ent->subexp_from; + /* Calculate the destination of the back reference, and append it + to MCTX->STATE_LOG. */ + if (to_idx == cur_str) + { + /* The backreference did epsilon transit, we must re-check all the + node in the current state. */ + re_node_set new_dests; + reg_errcode_t err2, err3; + next_node = dfa->edests[ent->node].elems[0]; + if (re_node_set_contains (cur_nodes, next_node)) + continue; + err = re_node_set_init_1 (&new_dests, next_node); + err2 = check_arrival_expand_ecl (dfa, &new_dests, subexp_num, + fl_open); + err3 = re_node_set_merge (cur_nodes, &new_dests); + re_node_set_free (&new_dests); + if (BE (err != REG_NOERROR || err2 != REG_NOERROR + || err3 != REG_NOERROR, 0)) + { + err = (err != REG_NOERROR ? err + : (err2 != REG_NOERROR ? err2 : err3)); + return err; + } + /* TODO: It is still inefficient... */ + cache_idx = cache_idx_start - 1; + continue; + } + else + { + re_node_set union_set; + next_node = dfa->nexts[ent->node]; + if (mctx->state_log[to_idx]) + { + int ret; + if (re_node_set_contains (&mctx->state_log[to_idx]->nodes, + next_node)) + continue; + err = re_node_set_init_copy (&union_set, + &mctx->state_log[to_idx]->nodes); + ret = re_node_set_insert (&union_set, next_node); + if (BE (err != REG_NOERROR || ret < 0, 0)) + { + re_node_set_free (&union_set); + err = err != REG_NOERROR ? err : REG_ESPACE; + return err; + } + } + else + { + err = re_node_set_init_1 (&union_set, next_node); + if (BE (err != REG_NOERROR, 0)) + return err; + } + mctx->state_log[to_idx] = re_acquire_state (&err, dfa, &union_set); + re_node_set_free (&union_set); + if (BE (mctx->state_log[to_idx] == NULL + && err != REG_NOERROR, 0)) + return err; + } + } + return REG_NOERROR; +} + +/* Build transition table for the state. + Return the new table if succeeded, otherwise return NULL. */ + +static re_dfastate_t ** +build_trtable (preg, state, fl_search) + const regex_t *preg; + const re_dfastate_t *state; + int fl_search; +{ + reg_errcode_t err; + re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + int i, j, k, ch; + int dests_node_malloced = 0, dest_states_malloced = 0; + int ndests; /* Number of the destination states from `state'. */ + re_dfastate_t **trtable; + re_dfastate_t **dest_states = NULL, **dest_states_word, **dest_states_nl; + re_node_set follows, *dests_node; + bitset *dests_ch; + bitset acceptable; + + /* We build DFA states which corresponds to the destination nodes + from `state'. `dests_node[i]' represents the nodes which i-th + destination state contains, and `dests_ch[i]' represents the + characters which i-th destination state accepts. */ +#ifdef _LIBC + if (__libc_use_alloca ((sizeof (re_node_set) + sizeof (bitset)) * SBC_MAX)) + dests_node = (re_node_set *) + alloca ((sizeof (re_node_set) + sizeof (bitset)) * SBC_MAX); + else +#endif + { + dests_node = (re_node_set *) + malloc ((sizeof (re_node_set) + sizeof (bitset)) * SBC_MAX); + if (BE (dests_node == NULL, 0)) + return NULL; + dests_node_malloced = 1; + } + dests_ch = (bitset *) (dests_node + SBC_MAX); + + /* Initialize transiton table. */ + trtable = (re_dfastate_t **) calloc (sizeof (re_dfastate_t *), SBC_MAX); + if (BE (trtable == NULL, 0)) + { + if (dests_node_malloced) + free (dests_node); + return NULL; + } + + /* At first, group all nodes belonging to `state' into several + destinations. */ + ndests = group_nodes_into_DFAstates (preg, state, dests_node, dests_ch); + if (BE (ndests <= 0, 0)) + { + if (dests_node_malloced) + free (dests_node); + /* Return NULL in case of an error, trtable otherwise. */ + if (ndests == 0) + return trtable; + free (trtable); + return NULL; + } + + err = re_node_set_alloc (&follows, ndests + 1); + if (BE (err != REG_NOERROR, 0)) + goto out_free; + +#ifdef _LIBC + if (__libc_use_alloca ((sizeof (re_node_set) + sizeof (bitset)) * SBC_MAX + + ndests * 3 * sizeof (re_dfastate_t *))) + dest_states = (re_dfastate_t **) + alloca (ndests * 3 * sizeof (re_dfastate_t *)); + else +#endif + { + dest_states = (re_dfastate_t **) + malloc (ndests * 3 * sizeof (re_dfastate_t *)); + if (BE (dest_states == NULL, 0)) + { +out_free: + if (dest_states_malloced) + free (dest_states); + re_node_set_free (&follows); + for (i = 0; i < ndests; ++i) + re_node_set_free (dests_node + i); + free (trtable); + if (dests_node_malloced) + free (dests_node); + return NULL; + } + dest_states_malloced = 1; + } + dest_states_word = dest_states + ndests; + dest_states_nl = dest_states_word + ndests; + bitset_empty (acceptable); + + /* Then build the states for all destinations. */ + for (i = 0; i < ndests; ++i) + { + int next_node; + re_node_set_empty (&follows); + /* Merge the follows of this destination states. */ + for (j = 0; j < dests_node[i].nelem; ++j) + { + next_node = dfa->nexts[dests_node[i].elems[j]]; + if (next_node != -1) + { + err = re_node_set_merge (&follows, dfa->eclosures + next_node); + if (BE (err != REG_NOERROR, 0)) + goto out_free; + } + } + /* If search flag is set, merge the initial state. */ + if (fl_search) + { +#ifdef RE_ENABLE_I18N + int not_initial = 0; + for (j = 0; j < follows.nelem; ++j) + if (dfa->nodes[follows.elems[j]].type == CHARACTER) + { + not_initial = dfa->nodes[follows.elems[j]].mb_partial; + break; + } + if (!not_initial) +#endif + { + err = re_node_set_merge (&follows, + dfa->init_state->entrance_nodes); + if (BE (err != REG_NOERROR, 0)) + goto out_free; + } + } + dest_states[i] = re_acquire_state_context (&err, dfa, &follows, 0); + if (BE (dest_states[i] == NULL && err != REG_NOERROR, 0)) + goto out_free; + /* If the new state has context constraint, + build appropriate states for these contexts. */ + if (dest_states[i]->has_constraint) + { + dest_states_word[i] = re_acquire_state_context (&err, dfa, &follows, + CONTEXT_WORD); + if (BE (dest_states_word[i] == NULL && err != REG_NOERROR, 0)) + goto out_free; + dest_states_nl[i] = re_acquire_state_context (&err, dfa, &follows, + CONTEXT_NEWLINE); + if (BE (dest_states_nl[i] == NULL && err != REG_NOERROR, 0)) + goto out_free; + } + else + { + dest_states_word[i] = dest_states[i]; + dest_states_nl[i] = dest_states[i]; + } + bitset_merge (acceptable, dests_ch[i]); + } + + /* Update the transition table. */ + /* For all characters ch...: */ + for (i = 0, ch = 0; i < BITSET_UINTS; ++i) + for (j = 0; j < UINT_BITS; ++j, ++ch) + if ((acceptable[i] >> j) & 1) + { + /* The current state accepts the character ch. */ + if (IS_WORD_CHAR (ch)) + { + for (k = 0; k < ndests; ++k) + if ((dests_ch[k][i] >> j) & 1) + { + /* k-th destination accepts the word character ch. */ + trtable[ch] = dest_states_word[k]; + /* There must be only one destination which accepts + character ch. See group_nodes_into_DFAstates. */ + break; + } + } + else /* not WORD_CHAR */ + { + for (k = 0; k < ndests; ++k) + if ((dests_ch[k][i] >> j) & 1) + { + /* k-th destination accepts the non-word character ch. */ + trtable[ch] = dest_states[k]; + /* There must be only one destination which accepts + character ch. See group_nodes_into_DFAstates. */ + break; + } + } + } + /* new line */ + if (bitset_contain (acceptable, NEWLINE_CHAR)) + { + /* The current state accepts newline character. */ + for (k = 0; k < ndests; ++k) + if (bitset_contain (dests_ch[k], NEWLINE_CHAR)) + { + /* k-th destination accepts newline character. */ + trtable[NEWLINE_CHAR] = dest_states_nl[k]; + /* There must be only one destination which accepts + newline. See group_nodes_into_DFAstates. */ + break; + } + } + + if (dest_states_malloced) + free (dest_states); + + re_node_set_free (&follows); + for (i = 0; i < ndests; ++i) + re_node_set_free (dests_node + i); + + if (dests_node_malloced) + free (dests_node); + + return trtable; +} + +/* Group all nodes belonging to STATE into several destinations. + Then for all destinations, set the nodes belonging to the destination + to DESTS_NODE[i] and set the characters accepted by the destination + to DEST_CH[i]. This function return the number of destinations. */ + +static int +group_nodes_into_DFAstates (preg, state, dests_node, dests_ch) + const regex_t *preg; + const re_dfastate_t *state; + re_node_set *dests_node; + bitset *dests_ch; +{ + reg_errcode_t err; + const re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + int i, j, k; + int ndests; /* Number of the destinations from `state'. */ + bitset accepts; /* Characters a node can accept. */ + const re_node_set *cur_nodes = &state->nodes; + bitset_empty (accepts); + ndests = 0; + + /* For all the nodes belonging to `state', */ + for (i = 0; i < cur_nodes->nelem; ++i) + { + re_token_t *node = &dfa->nodes[cur_nodes->elems[i]]; + re_token_type_t type = node->type; + unsigned int constraint = node->constraint; + + /* Enumerate all single byte character this node can accept. */ + if (type == CHARACTER) + bitset_set (accepts, node->opr.c); + else if (type == SIMPLE_BRACKET) + { + bitset_merge (accepts, node->opr.sbcset); + } + else if (type == OP_PERIOD) + { + bitset_set_all (accepts); + if (!(preg->syntax & RE_DOT_NEWLINE)) + bitset_clear (accepts, '\n'); + if (preg->syntax & RE_DOT_NOT_NULL) + bitset_clear (accepts, '\0'); + } + else + continue; + + /* Check the `accepts' and sift the characters which are not + match it the context. */ + if (constraint) + { + if (constraint & NEXT_WORD_CONSTRAINT) + for (j = 0; j < BITSET_UINTS; ++j) + accepts[j] &= dfa->word_char[j]; + if (constraint & NEXT_NOTWORD_CONSTRAINT) + for (j = 0; j < BITSET_UINTS; ++j) + accepts[j] &= ~dfa->word_char[j]; + if (constraint & NEXT_NEWLINE_CONSTRAINT) + { + int accepts_newline = bitset_contain (accepts, NEWLINE_CHAR); + bitset_empty (accepts); + if (accepts_newline) + bitset_set (accepts, NEWLINE_CHAR); + else + continue; + } + } + + /* Then divide `accepts' into DFA states, or create a new + state. */ + for (j = 0; j < ndests; ++j) + { + bitset intersec; /* Intersection sets, see below. */ + bitset remains; + /* Flags, see below. */ + int has_intersec, not_subset, not_consumed; + + /* Optimization, skip if this state doesn't accept the character. */ + if (type == CHARACTER && !bitset_contain (dests_ch[j], node->opr.c)) + continue; + + /* Enumerate the intersection set of this state and `accepts'. */ + has_intersec = 0; + for (k = 0; k < BITSET_UINTS; ++k) + has_intersec |= intersec[k] = accepts[k] & dests_ch[j][k]; + /* And skip if the intersection set is empty. */ + if (!has_intersec) + continue; + + /* Then check if this state is a subset of `accepts'. */ + not_subset = not_consumed = 0; + for (k = 0; k < BITSET_UINTS; ++k) + { + not_subset |= remains[k] = ~accepts[k] & dests_ch[j][k]; + not_consumed |= accepts[k] = accepts[k] & ~dests_ch[j][k]; + } + + /* If this state isn't a subset of `accepts', create a + new group state, which has the `remains'. */ + if (not_subset) + { + bitset_copy (dests_ch[ndests], remains); + bitset_copy (dests_ch[j], intersec); + err = re_node_set_init_copy (dests_node + ndests, &dests_node[j]); + if (BE (err != REG_NOERROR, 0)) + goto error_return; + ++ndests; + } + + /* Put the position in the current group. */ + err = re_node_set_insert (&dests_node[j], cur_nodes->elems[i]); + if (BE (err < 0, 0)) + goto error_return; + + /* If all characters are consumed, go to next node. */ + if (!not_consumed) + break; + } + /* Some characters remain, create a new group. */ + if (j == ndests) + { + bitset_copy (dests_ch[ndests], accepts); + err = re_node_set_init_1 (dests_node + ndests, cur_nodes->elems[i]); + if (BE (err != REG_NOERROR, 0)) + goto error_return; + ++ndests; + bitset_empty (accepts); + } + } + return ndests; + error_return: + for (j = 0; j < ndests; ++j) + re_node_set_free (dests_node + j); + return -1; +} + +#ifdef RE_ENABLE_I18N +/* Check how many bytes the node `dfa->nodes[node_idx]' accepts. + Return the number of the bytes the node accepts. + STR_IDX is the current index of the input string. + + This function handles the nodes which can accept one character, or + one collating element like '.', '[a-z]', opposite to the other nodes + can only accept one byte. */ + +static int +check_node_accept_bytes (preg, node_idx, input, str_idx) + const regex_t *preg; + int node_idx, str_idx; + const re_string_t *input; +{ + const re_dfa_t *dfa = (re_dfa_t *) preg->buffer; + const re_token_t *node = dfa->nodes + node_idx; + int elem_len = re_string_elem_size_at (input, str_idx); + int char_len = re_string_char_size_at (input, str_idx); + int i; +# ifdef _LIBC + int j; + uint32_t nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES); +# endif /* _LIBC */ + if (elem_len <= 1 && char_len <= 1) + return 0; + if (node->type == OP_PERIOD) + { + /* '.' accepts any one character except the following two cases. */ + if ((!(preg->syntax & RE_DOT_NEWLINE) && + re_string_byte_at (input, str_idx) == '\n') || + ((preg->syntax & RE_DOT_NOT_NULL) && + re_string_byte_at (input, str_idx) == '\0')) + return 0; + return char_len; + } + else if (node->type == COMPLEX_BRACKET) + { + const re_charset_t *cset = node->opr.mbcset; +# ifdef _LIBC + const unsigned char *pin = re_string_get_buffer (input) + str_idx; +# endif /* _LIBC */ + int match_len = 0; + wchar_t wc = ((cset->nranges || cset->nchar_classes || cset->nmbchars) + ? re_string_wchar_at (input, str_idx) : 0); + + /* match with multibyte character? */ + for (i = 0; i < cset->nmbchars; ++i) + if (wc == cset->mbchars[i]) + { + match_len = char_len; + goto check_node_accept_bytes_match; + } + /* match with character_class? */ + for (i = 0; i < cset->nchar_classes; ++i) + { + wctype_t wt = cset->char_classes[i]; + if (__iswctype (wc, wt)) + { + match_len = char_len; + goto check_node_accept_bytes_match; + } + } + +# ifdef _LIBC + if (nrules != 0) + { + unsigned int in_collseq = 0; + const int32_t *table, *indirect; + const unsigned char *weights, *extra; + const char *collseqwc; + int32_t idx; + /* This #include defines a local function! */ +# include <locale/weight.h> + + /* match with collating_symbol? */ + if (cset->ncoll_syms) + extra = (const unsigned char *) + _NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB); + for (i = 0; i < cset->ncoll_syms; ++i) + { + const unsigned char *coll_sym = extra + cset->coll_syms[i]; + /* Compare the length of input collating element and + the length of current collating element. */ + if (*coll_sym != elem_len) + continue; + /* Compare each bytes. */ + for (j = 0; j < *coll_sym; j++) + if (pin[j] != coll_sym[1 + j]) + break; + if (j == *coll_sym) + { + /* Match if every bytes is equal. */ + match_len = j; + goto check_node_accept_bytes_match; + } + } + + if (cset->nranges) + { + if (elem_len <= char_len) + { + collseqwc = _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQWC); + in_collseq = collseq_table_lookup (collseqwc, wc); + } + else + in_collseq = find_collation_sequence_value (pin, elem_len); + } + /* match with range expression? */ + for (i = 0; i < cset->nranges; ++i) + if (cset->range_starts[i] <= in_collseq + && in_collseq <= cset->range_ends[i]) + { + match_len = elem_len; + goto check_node_accept_bytes_match; + } + + /* match with equivalence_class? */ + if (cset->nequiv_classes) + { + const unsigned char *cp = pin; + table = (const int32_t *) + _NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB); + weights = (const unsigned char *) + _NL_CURRENT (LC_COLLATE, _NL_COLLATE_WEIGHTMB); + extra = (const unsigned char *) + _NL_CURRENT (LC_COLLATE, _NL_COLLATE_EXTRAMB); + indirect = (const int32_t *) + _NL_CURRENT (LC_COLLATE, _NL_COLLATE_INDIRECTMB); + idx = findidx (&cp); + if (idx > 0) + for (i = 0; i < cset->nequiv_classes; ++i) + { + int32_t equiv_class_idx = cset->equiv_classes[i]; + size_t weight_len = weights[idx]; + if (weight_len == weights[equiv_class_idx]) + { + int cnt = 0; + while (cnt <= weight_len + && (weights[equiv_class_idx + 1 + cnt] + == weights[idx + 1 + cnt])) + ++cnt; + if (cnt > weight_len) + { + match_len = elem_len; + goto check_node_accept_bytes_match; + } + } + } + } + } + else +# endif /* _LIBC */ + { + /* match with range expression? */ +#if __GNUC__ >= 2 + wchar_t cmp_buf[] = {L'\0', L'\0', wc, L'\0', L'\0', L'\0'}; +#else + wchar_t cmp_buf[] = {L'\0', L'\0', L'\0', L'\0', L'\0', L'\0'}; + cmp_buf[2] = wc; +#endif + for (i = 0; i < cset->nranges; ++i) + { + cmp_buf[0] = cset->range_starts[i]; + cmp_buf[4] = cset->range_ends[i]; + if (wcscoll (cmp_buf, cmp_buf + 2) <= 0 + && wcscoll (cmp_buf + 2, cmp_buf + 4) <= 0) + { + match_len = char_len; + goto check_node_accept_bytes_match; + } + } + } + check_node_accept_bytes_match: + if (!cset->non_match) + return match_len; + else + { + if (match_len > 0) + return 0; + else + return (elem_len > char_len) ? elem_len : char_len; + } + } + return 0; +} + +# ifdef _LIBC +static unsigned int +find_collation_sequence_value (mbs, mbs_len) + const unsigned char *mbs; + size_t mbs_len; +{ + uint32_t nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES); + if (nrules == 0) + { + if (mbs_len == 1) + { + /* No valid character. Match it as a single byte character. */ + const unsigned char *collseq = (const unsigned char *) + _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQMB); + return collseq[mbs[0]]; + } + return UINT_MAX; + } + else + { + int32_t idx; + const unsigned char *extra = (const unsigned char *) + _NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB); + + for (idx = 0; ;) + { + int mbs_cnt, found = 0; + int32_t elem_mbs_len; + /* Skip the name of collating element name. */ + idx = idx + extra[idx] + 1; + elem_mbs_len = extra[idx++]; + if (mbs_len == elem_mbs_len) + { + for (mbs_cnt = 0; mbs_cnt < elem_mbs_len; ++mbs_cnt) + if (extra[idx + mbs_cnt] != mbs[mbs_cnt]) + break; + if (mbs_cnt == elem_mbs_len) + /* Found the entry. */ + found = 1; + } + /* Skip the byte sequence of the collating element. */ + idx += elem_mbs_len; + /* Adjust for the alignment. */ + idx = (idx + 3) & ~3; + /* Skip the collation sequence value. */ + idx += sizeof (uint32_t); + /* Skip the wide char sequence of the collating element. */ + idx = idx + sizeof (uint32_t) * (extra[idx] + 1); + /* If we found the entry, return the sequence value. */ + if (found) + return *(uint32_t *) (extra + idx); + /* Skip the collation sequence value. */ + idx += sizeof (uint32_t); + } + } +} +# endif /* _LIBC */ +#endif /* RE_ENABLE_I18N */ + +/* Check whether the node accepts the byte which is IDX-th + byte of the INPUT. */ + +static int +check_node_accept (preg, node, mctx, idx) + const regex_t *preg; + const re_token_t *node; + const re_match_context_t *mctx; + int idx; +{ + unsigned char ch; + if (node->constraint) + { + /* The node has constraints. Check whether the current context + satisfies the constraints. */ + unsigned int context = re_string_context_at (mctx->input, idx, + mctx->eflags, + preg->newline_anchor); + if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context)) + return 0; + } + ch = re_string_byte_at (mctx->input, idx); + if (node->type == CHARACTER) + return node->opr.c == ch; + else if (node->type == SIMPLE_BRACKET) + return bitset_contain (node->opr.sbcset, ch); + else if (node->type == OP_PERIOD) + return !((ch == '\n' && !(preg->syntax & RE_DOT_NEWLINE)) + || (ch == '\0' && (preg->syntax & RE_DOT_NOT_NULL))); + else + return 0; +} + +/* Extend the buffers, if the buffers have run out. */ + +static reg_errcode_t +extend_buffers (mctx) + re_match_context_t *mctx; +{ + reg_errcode_t ret; + re_string_t *pstr = mctx->input; + + /* Double the lengthes of the buffers. */ + ret = re_string_realloc_buffers (pstr, pstr->bufs_len * 2); + if (BE (ret != REG_NOERROR, 0)) + return ret; + + if (mctx->state_log != NULL) + { + /* And double the length of state_log. */ + re_dfastate_t **new_array; + new_array = re_realloc (mctx->state_log, re_dfastate_t *, + pstr->bufs_len * 2); + if (BE (new_array == NULL, 0)) + return REG_ESPACE; + mctx->state_log = new_array; + } + + /* Then reconstruct the buffers. */ + if (pstr->icase) + { +#ifdef RE_ENABLE_I18N + if (re_mb_cur_max > 1) + build_wcs_upper_buffer (pstr); + else +#endif /* RE_ENABLE_I18N */ + build_upper_buffer (pstr); + } + else + { +#ifdef RE_ENABLE_I18N + if (re_mb_cur_max > 1) + build_wcs_buffer (pstr); + else +#endif /* RE_ENABLE_I18N */ + { + if (pstr->trans != NULL) + re_string_translate_buffer (pstr); + else + pstr->valid_len = pstr->bufs_len; + } + } + return REG_NOERROR; +} + + +/* Functions for matching context. */ + +/* Initialize MCTX. */ + +static reg_errcode_t +match_ctx_init (mctx, eflags, input, n) + re_match_context_t *mctx; + int eflags, n; + re_string_t *input; +{ + mctx->eflags = eflags; + mctx->input = input; + mctx->match_last = -1; + if (n > 0) + { + mctx->bkref_ents = re_malloc (struct re_backref_cache_entry, n); + mctx->sub_tops = re_malloc (re_sub_match_top_t *, n); + if (BE (mctx->bkref_ents == NULL || mctx->sub_tops == NULL, 0)) + return REG_ESPACE; + } + else + mctx->bkref_ents = NULL; + mctx->nbkref_ents = 0; + mctx->abkref_ents = n; + mctx->max_mb_elem_len = 1; + mctx->nsub_tops = 0; + mctx->asub_tops = n; + return REG_NOERROR; +} + +/* Clean the entries which depend on the current input in MCTX. + This function must be invoked when the matcher changes the start index + of the input, or changes the input string. */ + +static void +match_ctx_clean (mctx) + re_match_context_t *mctx; +{ + match_ctx_free_subtops (mctx); + mctx->nsub_tops = 0; + mctx->nbkref_ents = 0; +} + +/* Free all the memory associated with MCTX. */ + +static void +match_ctx_free (mctx) + re_match_context_t *mctx; +{ + match_ctx_free_subtops (mctx); + re_free (mctx->sub_tops); + re_free (mctx->bkref_ents); +} + +/* Free all the memory associated with MCTX->SUB_TOPS. */ + +static void +match_ctx_free_subtops (mctx) + re_match_context_t *mctx; +{ + int st_idx; + for (st_idx = 0; st_idx < mctx->nsub_tops; ++st_idx) + { + int sl_idx; + re_sub_match_top_t *top = mctx->sub_tops[st_idx]; + for (sl_idx = 0; sl_idx < top->nlasts; ++sl_idx) + { + re_sub_match_last_t *last = top->lasts[sl_idx]; + re_free (last->path.array); + re_free (last); + } + re_free (top->lasts); + if (top->path) + { + re_free (top->path->array); + re_free (top->path); + } + free (top); + } +} + +/* Add a new backreference entry to MCTX. + Note that we assume that caller never call this function with duplicate + entry, and call with STR_IDX which isn't smaller than any existing entry. +*/ + +static reg_errcode_t +match_ctx_add_entry (mctx, node, str_idx, from, to) + re_match_context_t *mctx; + int node, str_idx, from, to; +{ + if (mctx->nbkref_ents >= mctx->abkref_ents) + { + struct re_backref_cache_entry* new_entry; + new_entry = re_realloc (mctx->bkref_ents, struct re_backref_cache_entry, + mctx->abkref_ents * 2); + if (BE (new_entry == NULL, 0)) + { + re_free (mctx->bkref_ents); + return REG_ESPACE; + } + mctx->bkref_ents = new_entry; + memset (mctx->bkref_ents + mctx->nbkref_ents, '\0', + sizeof (struct re_backref_cache_entry) * mctx->abkref_ents); + mctx->abkref_ents *= 2; + } + mctx->bkref_ents[mctx->nbkref_ents].node = node; + mctx->bkref_ents[mctx->nbkref_ents].str_idx = str_idx; + mctx->bkref_ents[mctx->nbkref_ents].subexp_from = from; + mctx->bkref_ents[mctx->nbkref_ents].subexp_to = to; + mctx->bkref_ents[mctx->nbkref_ents++].flag = 0; + if (mctx->max_mb_elem_len < to - from) + mctx->max_mb_elem_len = to - from; + return REG_NOERROR; +} + +/* Search for the first entry which has the same str_idx. + Note that MCTX->BKREF_ENTS is already sorted by MCTX->STR_IDX. */ + +static int +search_cur_bkref_entry (mctx, str_idx) + re_match_context_t *mctx; + int str_idx; +{ + int left, right, mid; + right = mctx->nbkref_ents; + for (left = 0; left < right;) + { + mid = (left + right) / 2; + if (mctx->bkref_ents[mid].str_idx < str_idx) + left = mid + 1; + else + right = mid; + } + return left; +} + +static void +match_ctx_clear_flag (mctx) + re_match_context_t *mctx; +{ + int i; + for (i = 0; i < mctx->nbkref_ents; ++i) + { + mctx->bkref_ents[i].flag = 0; + } +} + +/* Register the node NODE, whose type is OP_OPEN_SUBEXP, and which matches + at STR_IDX. */ + +static reg_errcode_t +match_ctx_add_subtop (mctx, node, str_idx) + re_match_context_t *mctx; + int node, str_idx; +{ +#ifdef DEBUG + assert (mctx->sub_tops != NULL); + assert (mctx->asub_tops > 0); +#endif + if (mctx->nsub_tops == mctx->asub_tops) + { + re_sub_match_top_t **new_array; + mctx->asub_tops *= 2; + new_array = re_realloc (mctx->sub_tops, re_sub_match_top_t *, + mctx->asub_tops); + if (BE (new_array == NULL, 0)) + return REG_ESPACE; + mctx->sub_tops = new_array; + } + mctx->sub_tops[mctx->nsub_tops] = calloc (1, sizeof (re_sub_match_top_t)); + if (mctx->sub_tops[mctx->nsub_tops] == NULL) + return REG_ESPACE; + mctx->sub_tops[mctx->nsub_tops]->node = node; + mctx->sub_tops[mctx->nsub_tops++]->str_idx = str_idx; + return REG_NOERROR; +} + +/* Register the node NODE, whose type is OP_CLOSE_SUBEXP, and which matches + at STR_IDX, whose corresponding OP_OPEN_SUBEXP is SUB_TOP. */ + +static re_sub_match_last_t * +match_ctx_add_sublast (subtop, node, str_idx) + re_sub_match_top_t *subtop; + int node, str_idx; +{ + re_sub_match_last_t *new_entry; + if (subtop->nlasts == subtop->alasts) + { + re_sub_match_last_t **new_array; + subtop->alasts = 2 * subtop->alasts + 1; + new_array = re_realloc (subtop->lasts, re_sub_match_last_t *, + subtop->alasts); + if (BE (new_array == NULL, 0)) + return NULL; + subtop->lasts = new_array; + } + new_entry = calloc (1, sizeof (re_sub_match_last_t)); + if (BE (new_entry == NULL, 0)) + return NULL; + subtop->lasts[subtop->nlasts] = new_entry; + new_entry->node = node; + new_entry->str_idx = str_idx; + ++subtop->nlasts; + return new_entry; +} + +static void +sift_ctx_init (sctx, sifted_sts, limited_sts, last_node, last_str_idx, + check_subexp) + re_sift_context_t *sctx; + re_dfastate_t **sifted_sts, **limited_sts; + int last_node, last_str_idx, check_subexp; +{ + sctx->sifted_states = sifted_sts; + sctx->limited_states = limited_sts; + sctx->last_node = last_node; + sctx->last_str_idx = last_str_idx; + sctx->check_subexp = check_subexp; + sctx->cur_bkref = -1; + sctx->cls_subexp_idx = -1; + re_node_set_init_empty (&sctx->limits); +} |