1 /* Extended regular expression matching and search library.
2 Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License along
17 with this program; if not, write to the Free Software Foundation,
18 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
20 static reg_errcode_t match_ctx_init (re_match_context_t *cache, int eflags,
21 int n) internal_function;
22 static void match_ctx_clean (re_match_context_t *mctx) internal_function;
23 static void match_ctx_free (re_match_context_t *cache) internal_function;
24 static reg_errcode_t match_ctx_add_entry (re_match_context_t *cache, int node,
25 int str_idx, int from, int to)
27 static int search_cur_bkref_entry (re_match_context_t *mctx, int str_idx)
29 static reg_errcode_t match_ctx_add_subtop (re_match_context_t *mctx, int node,
30 int str_idx) internal_function;
31 static re_sub_match_last_t * match_ctx_add_sublast (re_sub_match_top_t *subtop,
32 int node, int str_idx)
34 static void sift_ctx_init (re_sift_context_t *sctx, re_dfastate_t **sifted_sts,
35 re_dfastate_t **limited_sts, int last_node,
38 static reg_errcode_t re_search_internal (const regex_t *preg,
39 const char *string, int length,
40 int start, int range, int stop,
41 size_t nmatch, regmatch_t pmatch[],
42 int eflags) internal_function;
43 static int re_search_2_stub (struct re_pattern_buffer *bufp,
44 const char *string1, int length1,
45 const char *string2, int length2,
46 int start, int range, struct re_registers *regs,
47 int stop, int ret_len) internal_function;
48 static int re_search_stub (struct re_pattern_buffer *bufp,
49 const char *string, int length, int start,
50 int range, int stop, struct re_registers *regs,
51 int ret_len) internal_function;
52 static unsigned re_copy_regs (struct re_registers *regs, regmatch_t *pmatch,
53 int nregs, int regs_allocated) internal_function;
54 static reg_errcode_t prune_impossible_nodes (re_match_context_t *mctx)
56 static int check_matching (re_match_context_t *mctx, int fl_longest_match,
59 static int check_halt_state_context (const re_match_context_t *mctx,
60 const re_dfastate_t *state, int idx)
62 static void update_regs (re_dfa_t *dfa, regmatch_t *pmatch,
63 regmatch_t *prev_idx_match, int cur_node,
64 int cur_idx, int nmatch) internal_function;
65 static reg_errcode_t push_fail_stack (struct re_fail_stack_t *fs,
66 int str_idx, int dest_node, int nregs,
68 re_node_set *eps_via_nodes) internal_function;
69 static reg_errcode_t set_regs (const regex_t *preg,
70 const re_match_context_t *mctx,
71 size_t nmatch, regmatch_t *pmatch,
72 int fl_backtrack) internal_function;
73 static reg_errcode_t free_fail_stack_return (struct re_fail_stack_t *fs) internal_function;
76 static int sift_states_iter_mb (const re_match_context_t *mctx,
77 re_sift_context_t *sctx,
78 int node_idx, int str_idx, int max_str_idx) internal_function;
79 #endif /* RE_ENABLE_I18N */
80 static reg_errcode_t sift_states_backward (re_match_context_t *mctx,
81 re_sift_context_t *sctx) internal_function;
82 static reg_errcode_t build_sifted_states (re_match_context_t *mctx,
83 re_sift_context_t *sctx, int str_idx,
84 re_node_set *cur_dest) internal_function;
85 static reg_errcode_t update_cur_sifted_state (re_match_context_t *mctx,
86 re_sift_context_t *sctx,
88 re_node_set *dest_nodes) internal_function;
89 static reg_errcode_t add_epsilon_src_nodes (re_dfa_t *dfa,
90 re_node_set *dest_nodes,
91 const re_node_set *candidates) internal_function;
92 static int check_dst_limits (re_match_context_t *mctx, re_node_set *limits,
93 int dst_node, int dst_idx, int src_node,
94 int src_idx) internal_function;
95 static int check_dst_limits_calc_pos_1 (re_match_context_t *mctx,
96 int boundaries, int subexp_idx,
97 int from_node, int bkref_idx) internal_function;
98 static int check_dst_limits_calc_pos (re_match_context_t *mctx,
99 int limit, int subexp_idx,
100 int node, int str_idx,
101 int bkref_idx) internal_function;
102 static reg_errcode_t check_subexp_limits (re_dfa_t *dfa,
103 re_node_set *dest_nodes,
104 const re_node_set *candidates,
106 struct re_backref_cache_entry *bkref_ents,
107 int str_idx) internal_function;
108 static reg_errcode_t sift_states_bkref (re_match_context_t *mctx,
109 re_sift_context_t *sctx,
110 int str_idx, const re_node_set *candidates) internal_function;
111 static reg_errcode_t merge_state_array (re_dfa_t *dfa, re_dfastate_t **dst,
112 re_dfastate_t **src, int num) internal_function;
113 static re_dfastate_t *find_recover_state (reg_errcode_t *err,
114 re_match_context_t *mctx) internal_function;
115 static re_dfastate_t *transit_state (reg_errcode_t *err,
116 re_match_context_t *mctx,
117 re_dfastate_t *state) internal_function;
118 static re_dfastate_t *merge_state_with_log (reg_errcode_t *err,
119 re_match_context_t *mctx,
120 re_dfastate_t *next_state) internal_function;
121 static reg_errcode_t check_subexp_matching_top (re_match_context_t *mctx,
122 re_node_set *cur_nodes,
123 int str_idx) internal_function;
125 static re_dfastate_t *transit_state_sb (reg_errcode_t *err,
126 re_match_context_t *mctx,
127 re_dfastate_t *pstate) internal_function;
129 #ifdef RE_ENABLE_I18N
130 static reg_errcode_t transit_state_mb (re_match_context_t *mctx,
131 re_dfastate_t *pstate) internal_function;
132 #endif /* RE_ENABLE_I18N */
133 static reg_errcode_t transit_state_bkref (re_match_context_t *mctx,
134 const re_node_set *nodes) internal_function;
135 static reg_errcode_t get_subexp (re_match_context_t *mctx,
136 int bkref_node, int bkref_str_idx) internal_function;
137 static reg_errcode_t get_subexp_sub (re_match_context_t *mctx,
138 const re_sub_match_top_t *sub_top,
139 re_sub_match_last_t *sub_last,
140 int bkref_node, int bkref_str) internal_function;
141 static int find_subexp_node (const re_dfa_t *dfa, const re_node_set *nodes,
142 int subexp_idx, int type) internal_function;
143 static reg_errcode_t check_arrival (re_match_context_t *mctx,
144 state_array_t *path, int top_node,
145 int top_str, int last_node, int last_str,
146 int type) internal_function;
147 static reg_errcode_t check_arrival_add_next_nodes (re_match_context_t *mctx,
149 re_node_set *cur_nodes,
150 re_node_set *next_nodes) internal_function;
151 static reg_errcode_t check_arrival_expand_ecl (re_dfa_t *dfa,
152 re_node_set *cur_nodes,
153 int ex_subexp, int type) internal_function;
154 static reg_errcode_t check_arrival_expand_ecl_sub (re_dfa_t *dfa,
155 re_node_set *dst_nodes,
156 int target, int ex_subexp,
157 int type) internal_function;
158 static reg_errcode_t expand_bkref_cache (re_match_context_t *mctx,
159 re_node_set *cur_nodes, int cur_str,
160 int subexp_num, int type) internal_function;
161 static int build_trtable (re_dfa_t *dfa,
162 re_dfastate_t *state) internal_function;
163 #ifdef RE_ENABLE_I18N
164 static int check_node_accept_bytes (re_dfa_t *dfa, int node_idx,
165 const re_string_t *input, int idx) internal_function;
167 static unsigned int find_collation_sequence_value (const unsigned char *mbs,
168 size_t name_len) internal_function;
170 #endif /* RE_ENABLE_I18N */
171 static int group_nodes_into_DFAstates (re_dfa_t *dfa,
172 const re_dfastate_t *state,
173 re_node_set *states_node,
174 bitset *states_ch) internal_function;
175 static int check_node_accept (const re_match_context_t *mctx,
176 const re_token_t *node, int idx) internal_function;
177 static reg_errcode_t extend_buffers (re_match_context_t *mctx) internal_function;
179 /* Entry point for POSIX code. */
181 /* regexec searches for a given pattern, specified by PREG, in the
184 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
185 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
186 least NMATCH elements, and we set them to the offsets of the
187 corresponding matched substrings.
189 EFLAGS specifies `execution flags' which affect matching: if
190 REG_NOTBOL is set, then ^ does not match at the beginning of the
191 string; if REG_NOTEOL is set, then $ does not match at the end.
193 We return 0 if we find a match and REG_NOMATCH if not. */
196 regexec (const regex_t *__restrict preg, const char *__restrict string,
197 size_t nmatch, regmatch_t pmatch[], int eflags)
202 re_dfa_t *dfa = (re_dfa_t *) preg->re_buffer;
205 if (eflags & ~(REG_NOTBOL | REG_NOTEOL | REG_STARTEND))
208 if (eflags & REG_STARTEND)
210 start = pmatch[0].rm_so;
211 length = pmatch[0].rm_eo;
216 length = strlen (string);
219 __libc_lock_lock (dfa->lock);
221 err = re_search_internal (preg, string, length, start, length - start,
222 length, 0, NULL, eflags);
224 err = re_search_internal (preg, string, length, start, length - start,
225 length, nmatch, pmatch, eflags);
226 __libc_lock_unlock (dfa->lock);
227 return err != REG_NOERROR;
231 # include <shlib-compat.h>
232 versioned_symbol (libc, __regexec, regexec, GLIBC_2_3_4);
234 # if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_3_4)
235 __typeof__ (__regexec) __compat_regexec;
238 attribute_compat_text_section
239 __compat_regexec (const regex_t *__restrict preg,
240 const char *__restrict string, size_t nmatch,
241 regmatch_t pmatch[], int eflags)
243 return regexec (preg, string, nmatch, pmatch,
244 eflags & (REG_NOTBOL | REG_NOTEOL));
246 compat_symbol (libc, __compat_regexec, regexec, GLIBC_2_0);
250 /* Entry points for GNU code. */
252 /* re_match, re_search, re_match_2, re_search_2
254 The former two functions operate on STRING with length LENGTH,
255 while the later two operate on concatenation of STRING1 and STRING2
256 with lengths LENGTH1 and LENGTH2, respectively.
258 re_match() matches the compiled pattern in BUFP against the string,
259 starting at index START.
261 re_search() first tries matching at index START, then it tries to match
262 starting from index START + 1, and so on. The last start position tried
263 is START + RANGE. (Thus RANGE = 0 forces re_search to operate the same
266 The parameter STOP of re_{match,search}_2 specifies that no match exceeding
267 the first STOP characters of the concatenation of the strings should be
270 If REGS is not NULL, and BUFP->re_no_sub is not set, the offsets of the match
271 and all groups is stroed in REGS. (For the "_2" variants, the offsets are
272 computed relative to the concatenation, not relative to the individual
275 On success, re_match* functions return the length of the match, re_search*
276 return the position of the start of the match. Return value -1 means no
277 match was found and -2 indicates an internal error. */
280 re_match (struct re_pattern_buffer *bufp, const char *string,
281 int length, int start, struct re_registers *regs)
283 return re_search_stub (bufp, string, length, start, 0, length, regs, 1);
286 weak_alias (__re_match, re_match)
290 re_search (struct re_pattern_buffer *bufp, const char *string,
291 int length, int start, int range, struct re_registers *regs)
293 return re_search_stub (bufp, string, length, start, range, length, regs, 0);
296 weak_alias (__re_search, re_search)
300 re_match_2 (struct re_pattern_buffer *bufp,
301 const char *string1, int length1,
302 const char *string2, int length2,
303 int start, struct re_registers *regs, int stop)
305 return re_search_2_stub (bufp, string1, length1, string2, length2,
306 start, 0, regs, stop, 1);
309 weak_alias (__re_match_2, re_match_2)
313 re_search_2 (struct re_pattern_buffer *bufp,
314 const char *string1, int length1,
315 const char *string2, int length2,
316 int start, int range, struct re_registers *regs, int stop)
318 return re_search_2_stub (bufp, string1, length1, string2, length2,
319 start, range, regs, stop, 0);
322 weak_alias (__re_search_2, re_search_2)
327 re_search_2_stub (struct re_pattern_buffer *bufp,
328 const char *string1, int length1,
329 const char *string2, int length2,
330 int start, int range, struct re_registers *regs, int stop,
335 int len = length1 + length2;
338 if (BE (length1 < 0 || length2 < 0 || stop < 0, 0))
341 /* Concatenate the strings. */
345 char *s = re_malloc (char, len);
347 if (BE (s == NULL, 0))
349 memcpy (s, string1, length1);
350 memcpy (s + length1, string2, length2);
359 rval = re_search_stub (bufp, str, len, start, range, stop, regs,
362 re_free ((char *) str);
366 /* The parameters have the same meaning as those of re_search.
367 Additional parameters:
368 If RET_LEN is nonzero the length of the match is returned (re_match style);
369 otherwise the position of the match is returned. */
373 re_search_stub (struct re_pattern_buffer *bufp,
374 const char *string, int length,
375 int start, int range, int stop, struct re_registers *regs,
378 reg_errcode_t result;
383 re_dfa_t *dfa = (re_dfa_t *) bufp->re_buffer;
386 /* Check for out-of-range. */
387 if (BE (start < 0 || start > length, 0))
389 if (BE (start + range > length, 0))
390 range = length - start;
391 else if (BE (start + range < 0, 0))
394 __libc_lock_lock (dfa->lock);
396 eflags |= (bufp->re_not_bol) ? REG_NOTBOL : 0;
397 eflags |= (bufp->re_not_eol) ? REG_NOTEOL : 0;
399 /* Compile fastmap if we haven't yet. */
400 if (range > 0 && bufp->re_fastmap != NULL && !bufp->re_fastmap_accurate)
401 re_compile_fastmap (bufp);
403 if (BE (bufp->re_no_sub, 0))
406 /* We need at least 1 register. */
409 else if (BE (bufp->re_regs_allocated == REG_FIXED
410 && regs->rm_num_regs < bufp->re_nsub + 1, 0))
412 nregs = regs->rm_num_regs;
413 if (BE (nregs < 1, 0))
415 /* Nothing can be copied to regs. */
421 nregs = bufp->re_nsub + 1;
422 pmatch = re_malloc (regmatch_t, nregs);
423 if (BE (pmatch == NULL, 0))
429 result = re_search_internal (bufp, string, length, start, range, stop,
430 nregs, pmatch, eflags);
434 /* I hope we needn't fill ther regs with -1's when no match was found. */
435 if (result != REG_NOERROR)
437 else if (regs != NULL)
439 /* If caller wants register contents data back, copy them. */
440 bufp->re_regs_allocated = re_copy_regs (regs, pmatch, nregs,
441 bufp->re_regs_allocated);
442 if (BE (bufp->re_regs_allocated == REG_UNALLOCATED, 0))
446 if (BE (rval == 0, 1))
450 assert (pmatch[0].rm_so == start);
451 rval = pmatch[0].rm_eo - start;
454 rval = pmatch[0].rm_so;
458 __libc_lock_unlock (dfa->lock);
464 re_copy_regs (struct re_registers *regs, regmatch_t *pmatch, int nregs,
467 int rval = REG_REALLOCATE;
469 int need_regs = nregs + 1;
470 /* We need one extra element beyond `rm_num_regs' for the `-1' marker GNU code
473 /* Have the register data arrays been allocated? */
474 if (regs_allocated == REG_UNALLOCATED)
475 { /* No. So allocate them with malloc. */
476 regs->rm_start = re_malloc (regoff_t, need_regs);
477 regs->rm_end = re_malloc (regoff_t, need_regs);
478 if (BE (regs->rm_start == NULL, 0) || BE (regs->rm_end == NULL, 0))
479 return REG_UNALLOCATED;
480 regs->rm_num_regs = need_regs;
482 else if (regs_allocated == REG_REALLOCATE)
483 { /* Yes. If we need more elements than were already
484 allocated, reallocate them. If we need fewer, just
486 if (BE (need_regs > regs->rm_num_regs, 0))
488 regoff_t *new_start =
489 re_realloc (regs->rm_start, regoff_t, need_regs);
490 regoff_t *new_end = re_realloc (regs->rm_end, regoff_t, need_regs);
491 if (BE (new_start == NULL, 0) || BE (new_end == NULL, 0))
492 return REG_UNALLOCATED;
493 regs->rm_start = new_start;
494 regs->rm_end = new_end;
495 regs->rm_num_regs = need_regs;
500 assert (regs_allocated == REG_FIXED);
501 /* This function may not be called with REG_FIXED and nregs too big. */
502 assert (regs->rm_num_regs >= nregs);
507 for (i = 0; i < nregs; ++i)
509 regs->rm_start[i] = pmatch[i].rm_so;
510 regs->rm_end[i] = pmatch[i].rm_eo;
512 for ( ; i < regs->rm_num_regs; ++i)
513 regs->rm_start[i] = regs->rm_end[i] = -1;
518 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
519 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
520 this memory for recording register information. STARTS and ENDS
521 must be allocated using the malloc library routine, and must each
522 be at least NUM_REGS * sizeof (regoff_t) bytes long.
524 If NUM_REGS == 0, then subsequent matches should allocate their own
527 Unless this function is called, the first search or match using
528 PATTERN_BUFFER will allocate its own register data, without
529 freeing the old data. */
532 re_set_registers (struct re_pattern_buffer *bufp, struct re_registers *regs,
533 unsigned int num_regs, regoff_t *starts, regoff_t *ends)
537 bufp->re_regs_allocated = REG_REALLOCATE;
538 regs->rm_num_regs = num_regs;
539 regs->rm_start = starts;
544 bufp->re_regs_allocated = REG_UNALLOCATED;
545 regs->rm_num_regs = 0;
546 regs->rm_start = regs->rm_end = NULL;
550 weak_alias (__re_set_registers, re_set_registers)
553 /* Entry points compatible with 4.2 BSD regex library. We don't define
554 them unless specifically requested. */
556 #if defined _REGEX_RE_COMP || defined _LIBC
564 return 0 == regexec (&re_comp_buf, s, 0, NULL, 0);
566 #endif /* _REGEX_RE_COMP */
568 /* Internal entry point. */
570 /* Searches for a compiled pattern PREG in the string STRING, whose
571 length is LENGTH. NMATCH, PMATCH, and EFLAGS have the same
572 mingings with regexec. START, and RANGE have the same meanings
574 Return REG_NOERROR if we find a match, and REG_NOMATCH if not,
575 otherwise return the error code.
576 Note: We assume front end functions already check ranges.
577 (START + RANGE >= 0 && START + RANGE <= LENGTH) */
581 re_search_internal (const regex_t *preg,
582 const char *string, int length,
583 int start, int range, int stop,
584 size_t nmatch, regmatch_t pmatch[],
588 re_dfa_t *dfa = (re_dfa_t *) preg->re_buffer;
589 int left_lim, right_lim, incr;
590 int fl_longest_match, match_first, match_kind, match_last = -1;
593 #if defined _LIBC || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)
594 re_match_context_t mctx = { .dfa = dfa };
596 re_match_context_t mctx;
598 char *fastmap = (preg->re_fastmap != NULL && preg->re_fastmap_accurate
599 && range && !preg->re_can_be_null) ? preg->re_fastmap : NULL;
600 unsigned REG_TRANSLATE_TYPE t =
601 (unsigned REG_TRANSLATE_TYPE) preg->re_translate;
603 #if !(defined _LIBC || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L))
604 memset (&mctx, '\0', sizeof (re_match_context_t));
608 extra_nmatch = (nmatch > preg->re_nsub) ? nmatch - (preg->re_nsub + 1) : 0;
609 nmatch -= extra_nmatch;
611 /* Check if the DFA haven't been compiled. */
612 if (BE (preg->re_used == 0 || dfa->init_state == NULL
613 || dfa->init_state_word == NULL || dfa->init_state_nl == NULL
614 || dfa->init_state_begbuf == NULL, 0))
618 /* We assume front-end functions already check them. */
619 assert (start + range >= 0 && start + range <= length);
622 /* If initial states with non-begbuf contexts have no elements,
623 the regex must be anchored. If preg->re_newline_anchor is set,
624 we'll never use init_state_nl, so do not check it. */
625 if (dfa->init_state->nodes.nelem == 0
626 && dfa->init_state_word->nodes.nelem == 0
627 && (dfa->init_state_nl->nodes.nelem == 0
628 || !preg->re_newline_anchor))
630 if (start != 0 && start + range != 0)
635 /* We must check the longest matching, if nmatch > 0. */
636 fl_longest_match = (nmatch != 0 || dfa->nbackref);
638 err = re_string_allocate (&mctx.input, string, length, dfa->nodes_len + 1,
640 preg->re_syntax & REG_IGNORE_CASE, dfa);
641 if (BE (err != REG_NOERROR, 0))
643 mctx.input.stop = stop;
644 mctx.input.raw_stop = stop;
645 mctx.input.newline_anchor = preg->re_newline_anchor;
647 err = match_ctx_init (&mctx, eflags, dfa->nbackref * 2);
648 if (BE (err != REG_NOERROR, 0))
651 /* We will log all the DFA states through which the dfa pass,
652 if nmatch > 1, or this dfa has "multibyte node", which is a
653 back-reference or a node which can accept multibyte character or
654 multi character collating element. */
655 if (nmatch > 1 || dfa->has_mb_node)
657 mctx.state_log = re_malloc (re_dfastate_t *, mctx.input.bufs_len + 1);
658 if (BE (mctx.state_log == NULL, 0))
665 mctx.state_log = NULL;
668 mctx.input.tip_context = (eflags & REG_NOTBOL) ? CONTEXT_BEGBUF
669 : CONTEXT_NEWLINE | CONTEXT_BEGBUF;
671 /* Check incrementally whether of not the input string match. */
672 incr = (range < 0) ? -1 : 1;
673 left_lim = (range < 0) ? start + range : start;
674 right_lim = (range < 0) ? start : start + range;
675 sb = dfa->mb_cur_max == 1;
678 ? ((sb || !(preg->re_syntax & REG_IGNORE_CASE || t) ? 4 : 0)
679 | (range >= 0 ? 2 : 0)
680 | (t != NULL ? 1 : 0))
683 for (;; match_first += incr)
686 if (match_first < left_lim || right_lim < match_first)
689 /* Advance as rapidly as possible through the string, until we
690 find a plausible place to start matching. This may be done
691 with varying efficiency, so there are various possibilities:
692 only the most common of them are specialized, in order to
693 save on code size. We use a switch statement for speed. */
701 /* Fastmap with single-byte translation, match forward. */
702 while (BE (match_first < right_lim, 1)
703 && !fastmap[t[(unsigned char) string[match_first]]])
705 goto forward_match_found_start_or_reached_end;
708 /* Fastmap without translation, match forward. */
709 while (BE (match_first < right_lim, 1)
710 && !fastmap[(unsigned char) string[match_first]])
713 forward_match_found_start_or_reached_end:
714 if (BE (match_first == right_lim, 0))
716 ch = match_first >= length
717 ? 0 : (unsigned char) string[match_first];
718 if (!fastmap[t ? t[ch] : ch])
725 /* Fastmap without multi-byte translation, match backwards. */
726 while (match_first >= left_lim)
728 ch = match_first >= length
729 ? 0 : (unsigned char) string[match_first];
730 if (fastmap[t ? t[ch] : ch])
734 if (match_first < left_lim)
739 /* In this case, we can't determine easily the current byte,
740 since it might be a component byte of a multibyte
741 character. Then we use the constructed buffer instead. */
744 /* If MATCH_FIRST is out of the valid range, reconstruct the
746 unsigned int offset = match_first - mctx.input.raw_mbs_idx;
747 if (BE (offset >= (unsigned int) mctx.input.valid_raw_len, 0))
749 err = re_string_reconstruct (&mctx.input, match_first,
751 if (BE (err != REG_NOERROR, 0))
754 offset = match_first - mctx.input.raw_mbs_idx;
756 /* If MATCH_FIRST is out of the buffer, leave it as '\0'.
757 Note that MATCH_FIRST must not be smaller than 0. */
758 ch = (match_first >= length
759 ? 0 : re_string_byte_at (&mctx.input, offset));
763 if (match_first < left_lim || match_first > right_lim)
772 /* Reconstruct the buffers so that the matcher can assume that
773 the matching starts from the beginning of the buffer. */
774 err = re_string_reconstruct (&mctx.input, match_first, eflags);
775 if (BE (err != REG_NOERROR, 0))
778 #ifdef RE_ENABLE_I18N
779 /* Don't consider this char as a possible match start if it part,
780 yet isn't the head, of a multibyte character. */
781 if (!sb && !re_string_first_byte (&mctx.input, 0))
785 /* It seems to be appropriate one, then use the matcher. */
786 /* We assume that the matching starts from 0. */
787 mctx.state_log_top = mctx.nbkref_ents = mctx.max_mb_elem_len = 0;
788 match_last = check_matching (&mctx, fl_longest_match,
789 range >= 0 ? &match_first : NULL);
790 if (match_last != -1)
792 if (BE (match_last == -2, 0))
799 mctx.match_last = match_last;
800 if ((!preg->re_no_sub && nmatch > 1) || dfa->nbackref)
802 re_dfastate_t *pstate = mctx.state_log[match_last];
803 mctx.last_node = check_halt_state_context (&mctx, pstate,
806 if ((!preg->re_no_sub && nmatch > 1 && dfa->has_plural_match)
809 err = prune_impossible_nodes (&mctx);
810 if (err == REG_NOERROR)
812 if (BE (err != REG_NOMATCH, 0))
817 break; /* We found a match. */
821 match_ctx_clean (&mctx);
825 assert (match_last != -1);
826 assert (err == REG_NOERROR);
829 /* Set pmatch[] if we need. */
834 /* Initialize registers. */
835 for (reg_idx = 1; reg_idx < nmatch; ++reg_idx)
836 pmatch[reg_idx].rm_so = pmatch[reg_idx].rm_eo = -1;
838 /* Set the points where matching start/end. */
840 pmatch[0].rm_eo = mctx.match_last;
842 if (!preg->re_no_sub && nmatch > 1)
844 err = set_regs (preg, &mctx, nmatch, pmatch,
845 dfa->has_plural_match && dfa->nbackref > 0);
846 if (BE (err != REG_NOERROR, 0))
850 /* At last, add the offset to the each registers, since we slided
851 the buffers so that we could assume that the matching starts
853 for (reg_idx = 0; reg_idx < nmatch; ++reg_idx)
854 if (pmatch[reg_idx].rm_so != -1)
856 #ifdef RE_ENABLE_I18N
857 if (BE (mctx.input.offsets_needed != 0, 0))
859 if (pmatch[reg_idx].rm_so == mctx.input.valid_len)
860 pmatch[reg_idx].rm_so += mctx.input.valid_raw_len - mctx.input.valid_len;
862 pmatch[reg_idx].rm_so = mctx.input.offsets[pmatch[reg_idx].rm_so];
863 if (pmatch[reg_idx].rm_eo == mctx.input.valid_len)
864 pmatch[reg_idx].rm_eo += mctx.input.valid_raw_len - mctx.input.valid_len;
866 pmatch[reg_idx].rm_eo = mctx.input.offsets[pmatch[reg_idx].rm_eo];
869 assert (mctx.input.offsets_needed == 0);
871 pmatch[reg_idx].rm_so += match_first;
872 pmatch[reg_idx].rm_eo += match_first;
874 for (reg_idx = 0; reg_idx < extra_nmatch; ++reg_idx)
876 pmatch[nmatch + reg_idx].rm_so = -1;
877 pmatch[nmatch + reg_idx].rm_eo = -1;
881 for (reg_idx = 0; reg_idx + 1 < nmatch; reg_idx++)
882 if (dfa->subexp_map[reg_idx] != reg_idx)
884 pmatch[reg_idx + 1].rm_so
885 = pmatch[dfa->subexp_map[reg_idx] + 1].rm_so;
886 pmatch[reg_idx + 1].rm_eo
887 = pmatch[dfa->subexp_map[reg_idx] + 1].rm_eo;
892 re_free (mctx.state_log);
894 match_ctx_free (&mctx);
895 re_string_destruct (&mctx.input);
901 prune_impossible_nodes (re_match_context_t *mctx)
903 re_dfa_t *const dfa = mctx->dfa;
904 int halt_node, match_last;
906 re_dfastate_t **sifted_states;
907 re_dfastate_t **lim_states = NULL;
908 re_sift_context_t sctx;
910 assert (mctx->state_log != NULL);
912 match_last = mctx->match_last;
913 halt_node = mctx->last_node;
914 sifted_states = re_malloc (re_dfastate_t *, match_last + 1);
915 if (BE (sifted_states == NULL, 0))
922 lim_states = re_malloc (re_dfastate_t *, match_last + 1);
923 if (BE (lim_states == NULL, 0))
930 memset (lim_states, '\0',
931 sizeof (re_dfastate_t *) * (match_last + 1));
932 sift_ctx_init (&sctx, sifted_states, lim_states, halt_node,
934 ret = sift_states_backward (mctx, &sctx);
935 re_node_set_free (&sctx.limits);
936 if (BE (ret != REG_NOERROR, 0))
938 if (sifted_states[0] != NULL || lim_states[0] != NULL)
948 } while (mctx->state_log[match_last] == NULL
949 || !mctx->state_log[match_last]->halt);
950 halt_node = check_halt_state_context (mctx,
951 mctx->state_log[match_last],
954 ret = merge_state_array (dfa, sifted_states, lim_states,
956 re_free (lim_states);
958 if (BE (ret != REG_NOERROR, 0))
963 sift_ctx_init (&sctx, sifted_states, lim_states, halt_node, match_last);
964 ret = sift_states_backward (mctx, &sctx);
965 re_node_set_free (&sctx.limits);
966 if (BE (ret != REG_NOERROR, 0))
969 re_free (mctx->state_log);
970 mctx->state_log = sifted_states;
971 sifted_states = NULL;
972 mctx->last_node = halt_node;
973 mctx->match_last = match_last;
976 re_free (sifted_states);
977 re_free (lim_states);
981 /* Acquire an initial state and return it.
982 We must select appropriate initial state depending on the context,
983 since initial states may have constraints like "\<", "^", etc.. */
985 static inline re_dfastate_t *
986 __attribute ((always_inline)) internal_function
987 acquire_init_state_context (reg_errcode_t *err, const re_match_context_t *mctx,
990 re_dfa_t *const dfa = mctx->dfa;
991 if (dfa->init_state->has_constraint)
993 unsigned int context;
994 context = re_string_context_at (&mctx->input, idx - 1, mctx->eflags);
995 if (IS_WORD_CONTEXT (context))
996 return dfa->init_state_word;
997 else if (IS_ORDINARY_CONTEXT (context))
998 return dfa->init_state;
999 else if (IS_BEGBUF_CONTEXT (context) && IS_NEWLINE_CONTEXT (context))
1000 return dfa->init_state_begbuf;
1001 else if (IS_NEWLINE_CONTEXT (context))
1002 return dfa->init_state_nl;
1003 else if (IS_BEGBUF_CONTEXT (context))
1005 /* It is relatively rare case, then calculate on demand. */
1006 return re_acquire_state_context (err, dfa,
1007 dfa->init_state->entrance_nodes,
1011 /* Must not happen? */
1012 return dfa->init_state;
1015 return dfa->init_state;
1018 /* Check whether the regular expression match input string INPUT or not,
1019 and return the index where the matching end, return -1 if not match,
1020 or return -2 in case of an error.
1021 FL_LONGEST_MATCH means we want the POSIX longest matching.
1022 If P_MATCH_FIRST is not NULL, and the match fails, it is set to the
1023 next place where we may want to try matching.
1024 Note that the matcher assume that the maching starts from the current
1025 index of the buffer. */
1029 check_matching (re_match_context_t *mctx, int fl_longest_match,
1032 re_dfa_t *const dfa = mctx->dfa;
1035 int match_last = -1;
1036 int cur_str_idx = re_string_cur_idx (&mctx->input);
1037 re_dfastate_t *cur_state;
1038 int at_init_state = p_match_first != NULL;
1039 int next_start_idx = cur_str_idx;
1042 cur_state = acquire_init_state_context (&err, mctx, cur_str_idx);
1043 /* An initial state must not be NULL (invalid). */
1044 if (BE (cur_state == NULL, 0))
1046 assert (err == REG_ESPACE);
1050 if (mctx->state_log != NULL)
1052 mctx->state_log[cur_str_idx] = cur_state;
1054 /* Check OP_OPEN_SUBEXP in the initial state in case that we use them
1055 later. E.g. Processing back references. */
1056 if (BE (dfa->nbackref, 0))
1059 err = check_subexp_matching_top (mctx, &cur_state->nodes, 0);
1060 if (BE (err != REG_NOERROR, 0))
1063 if (cur_state->has_backref)
1065 err = transit_state_bkref (mctx, &cur_state->nodes);
1066 if (BE (err != REG_NOERROR, 0))
1072 /* If the RE accepts NULL string. */
1073 if (BE (cur_state->halt, 0))
1075 if (!cur_state->has_constraint
1076 || check_halt_state_context (mctx, cur_state, cur_str_idx))
1078 if (!fl_longest_match)
1082 match_last = cur_str_idx;
1088 while (!re_string_eoi (&mctx->input))
1090 re_dfastate_t *old_state = cur_state;
1091 int next_char_idx = re_string_cur_idx (&mctx->input) + 1;
1093 if (BE (next_char_idx >= mctx->input.bufs_len, 0)
1094 || (BE (next_char_idx >= mctx->input.valid_len, 0)
1095 && mctx->input.valid_len < mctx->input.len))
1097 err = extend_buffers (mctx);
1098 if (BE (err != REG_NOERROR, 0))
1100 assert (err == REG_ESPACE);
1105 cur_state = transit_state (&err, mctx, cur_state);
1106 if (mctx->state_log != NULL)
1107 cur_state = merge_state_with_log (&err, mctx, cur_state);
1109 if (cur_state == NULL)
1111 /* Reached the invalid state or an error. Try to recover a valid
1112 state using the state log, if available and if we have not
1113 already found a valid (even if not the longest) match. */
1114 if (BE (err != REG_NOERROR, 0))
1117 if (mctx->state_log == NULL
1118 || (match && !fl_longest_match)
1119 || (cur_state = find_recover_state (&err, mctx)) == NULL)
1123 if (BE (at_init_state, 0))
1125 if (old_state == cur_state)
1126 next_start_idx = next_char_idx;
1131 if (cur_state->halt)
1133 /* Reached a halt state.
1134 Check the halt state can satisfy the current context. */
1135 if (!cur_state->has_constraint
1136 || check_halt_state_context (mctx, cur_state,
1137 re_string_cur_idx (&mctx->input)))
1139 /* We found an appropriate halt state. */
1140 match_last = re_string_cur_idx (&mctx->input);
1143 /* We found a match, do not modify match_first below. */
1144 p_match_first = NULL;
1145 if (!fl_longest_match)
1152 *p_match_first += next_start_idx;
1157 /* Check NODE match the current context. */
1161 check_halt_node_context (const re_dfa_t *dfa, int node, unsigned int context)
1163 re_token_type_t type = dfa->nodes[node].type;
1164 unsigned int constraint = dfa->nodes[node].constraint;
1165 if (type != END_OF_RE)
1169 if (NOT_SATISFY_NEXT_CONSTRAINT (constraint, context))
1174 /* Check the halt state STATE match the current context.
1175 Return 0 if not match, if the node, STATE has, is a halt node and
1176 match the context, return the node. */
1180 check_halt_state_context (const re_match_context_t *mctx,
1181 const re_dfastate_t *state, int idx)
1184 unsigned int context;
1186 assert (state->halt);
1188 context = re_string_context_at (&mctx->input, idx, mctx->eflags);
1189 for (i = 0; i < state->nodes.nelem; ++i)
1190 if (check_halt_node_context (mctx->dfa, state->nodes.elems[i], context))
1191 return state->nodes.elems[i];
1195 /* Compute the next node to which "NFA" transit from NODE("NFA" is a NFA
1196 corresponding to the DFA).
1197 Return the destination node, and update EPS_VIA_NODES, return -1 in case
1202 proceed_next_node (const re_match_context_t *mctx,
1203 int nregs, regmatch_t *regs, int *pidx, int node,
1204 re_node_set *eps_via_nodes, struct re_fail_stack_t *fs)
1206 re_dfa_t *const dfa = mctx->dfa;
1208 if (IS_EPSILON_NODE (dfa->nodes[node].type))
1210 re_node_set *cur_nodes = &mctx->state_log[*pidx]->nodes;
1211 re_node_set *edests = &dfa->edests[node];
1213 err = re_node_set_insert (eps_via_nodes, node);
1214 if (BE (err < 0, 0))
1216 /* Pick up a valid destination, or return -1 if none is found. */
1217 for (dest_node = -1, i = 0; i < edests->nelem; ++i)
1219 int candidate = edests->elems[i];
1220 if (!re_node_set_contains (cur_nodes, candidate))
1222 if (dest_node == -1)
1223 dest_node = candidate;
1227 /* In order to avoid infinite loop like "(a*)*", return the second
1228 epsilon-transition if the first was already considered. */
1229 if (re_node_set_contains (eps_via_nodes, dest_node))
1232 /* Otherwise, push the second epsilon-transition on the fail stack. */
1234 && push_fail_stack (fs, *pidx, candidate, nregs, regs,
1238 /* We know we are going to exit. */
1247 re_token_type_t type = dfa->nodes[node].type;
1249 #ifdef RE_ENABLE_I18N
1250 if (dfa->nodes[node].accept_mb)
1251 naccepted = check_node_accept_bytes (dfa, node, &mctx->input, *pidx);
1253 #endif /* RE_ENABLE_I18N */
1254 if (type == OP_BACK_REF)
1256 int subexp_idx = dfa->nodes[node].opr.idx + 1;
1257 naccepted = regs[subexp_idx].rm_eo - regs[subexp_idx].rm_so;
1260 if (regs[subexp_idx].rm_so == -1 || regs[subexp_idx].rm_eo == -1)
1264 char *buf = (char *) re_string_get_buffer (&mctx->input);
1265 if (memcmp (buf + regs[subexp_idx].rm_so, buf + *pidx,
1274 err = re_node_set_insert (eps_via_nodes, node);
1275 if (BE (err < 0, 0))
1277 dest_node = dfa->edests[node].elems[0];
1278 if (re_node_set_contains (&mctx->state_log[*pidx]->nodes,
1285 || check_node_accept (mctx, dfa->nodes + node, *pidx))
1287 int dest_node = dfa->nexts[node];
1288 *pidx = (naccepted == 0) ? *pidx + 1 : *pidx + naccepted;
1289 if (fs && (*pidx > mctx->match_last || mctx->state_log[*pidx] == NULL
1290 || !re_node_set_contains (&mctx->state_log[*pidx]->nodes,
1293 re_node_set_empty (eps_via_nodes);
1300 static reg_errcode_t
1302 push_fail_stack (struct re_fail_stack_t *fs, int str_idx, int dest_node,
1303 int nregs, regmatch_t *regs, re_node_set *eps_via_nodes)
1306 int num = fs->num++;
1307 if (fs->num == fs->alloc)
1309 struct re_fail_stack_ent_t *new_array =
1310 re_realloc (fs->stack, struct re_fail_stack_ent_t, fs->alloc * 2);
1311 if (new_array == NULL)
1314 fs->stack = new_array;
1316 fs->stack[num].idx = str_idx;
1317 fs->stack[num].node = dest_node;
1318 fs->stack[num].regs = re_malloc (regmatch_t, nregs);
1319 if (fs->stack[num].regs == NULL)
1321 memcpy (fs->stack[num].regs, regs, sizeof (regmatch_t) * nregs);
1322 err = re_node_set_init_copy (&fs->stack[num].eps_via_nodes, eps_via_nodes);
1328 pop_fail_stack (struct re_fail_stack_t *fs, int *pidx,
1329 int nregs, regmatch_t *regs, re_node_set *eps_via_nodes)
1331 int num = --fs->num;
1333 *pidx = fs->stack[num].idx;
1334 memcpy (regs, fs->stack[num].regs, sizeof (regmatch_t) * nregs);
1335 re_node_set_free (eps_via_nodes);
1336 re_free (fs->stack[num].regs);
1337 *eps_via_nodes = fs->stack[num].eps_via_nodes;
1338 return fs->stack[num].node;
1341 /* Set the positions where the subexpressions are starts/ends to registers
1343 Note: We assume that pmatch[0] is already set, and
1344 pmatch[i].rm_so == pmatch[i].rm_eo == -1 for 0 < i < nmatch. */
1346 static reg_errcode_t
1348 set_regs (const regex_t *preg, const re_match_context_t *mctx,
1349 size_t nmatch, regmatch_t *pmatch, int fl_backtrack)
1351 re_dfa_t *dfa = (re_dfa_t *) preg->re_buffer;
1353 re_node_set eps_via_nodes;
1354 struct re_fail_stack_t *fs;
1355 struct re_fail_stack_t fs_body = { 0, 2, NULL };
1356 regmatch_t *prev_idx_match;
1357 int prev_idx_match_malloced = 0;
1360 assert (nmatch > 1);
1361 assert (mctx->state_log != NULL);
1366 fs->stack = re_malloc (struct re_fail_stack_ent_t, fs->alloc);
1367 if (fs->stack == NULL)
1373 cur_node = dfa->init_node;
1374 re_node_set_init_empty (&eps_via_nodes);
1376 if (__libc_use_alloca (nmatch * sizeof (regmatch_t)))
1377 prev_idx_match = (regmatch_t *) alloca (nmatch * sizeof (regmatch_t));
1380 prev_idx_match = re_malloc (regmatch_t, nmatch);
1381 if (prev_idx_match == NULL)
1383 free_fail_stack_return (fs);
1386 prev_idx_match_malloced = 1;
1388 memcpy (prev_idx_match, pmatch, sizeof (regmatch_t) * nmatch);
1390 for (idx = pmatch[0].rm_so; idx <= pmatch[0].rm_eo ;)
1392 update_regs (dfa, pmatch, prev_idx_match, cur_node, idx, nmatch);
1394 if (idx == pmatch[0].rm_eo && cur_node == mctx->last_node)
1399 for (reg_idx = 0; reg_idx < nmatch; ++reg_idx)
1400 if (pmatch[reg_idx].rm_so > -1 && pmatch[reg_idx].rm_eo == -1)
1402 if (reg_idx == nmatch)
1404 re_node_set_free (&eps_via_nodes);
1405 if (prev_idx_match_malloced)
1406 re_free (prev_idx_match);
1407 return free_fail_stack_return (fs);
1409 cur_node = pop_fail_stack (fs, &idx, nmatch, pmatch,
1414 re_node_set_free (&eps_via_nodes);
1415 if (prev_idx_match_malloced)
1416 re_free (prev_idx_match);
1421 /* Proceed to next node. */
1422 cur_node = proceed_next_node (mctx, nmatch, pmatch, &idx, cur_node,
1423 &eps_via_nodes, fs);
1425 if (BE (cur_node < 0, 0))
1427 if (BE (cur_node == -2, 0))
1429 re_node_set_free (&eps_via_nodes);
1430 if (prev_idx_match_malloced)
1431 re_free (prev_idx_match);
1432 free_fail_stack_return (fs);
1436 cur_node = pop_fail_stack (fs, &idx, nmatch, pmatch,
1440 re_node_set_free (&eps_via_nodes);
1441 if (prev_idx_match_malloced)
1442 re_free (prev_idx_match);
1447 re_node_set_free (&eps_via_nodes);
1448 if (prev_idx_match_malloced)
1449 re_free (prev_idx_match);
1450 return free_fail_stack_return (fs);
1453 static reg_errcode_t
1455 free_fail_stack_return (struct re_fail_stack_t *fs)
1460 for (fs_idx = 0; fs_idx < fs->num; ++fs_idx)
1462 re_node_set_free (&fs->stack[fs_idx].eps_via_nodes);
1463 re_free (fs->stack[fs_idx].regs);
1465 re_free (fs->stack);
1472 update_regs (re_dfa_t *dfa, regmatch_t *pmatch, regmatch_t *prev_idx_match,
1473 int cur_node, int cur_idx, int nmatch)
1475 int type = dfa->nodes[cur_node].type;
1476 if (type == OP_OPEN_SUBEXP)
1478 int reg_num = dfa->nodes[cur_node].opr.idx + 1;
1480 /* We are at the first node of this sub expression. */
1481 if (reg_num < nmatch)
1483 pmatch[reg_num].rm_so = cur_idx;
1484 pmatch[reg_num].rm_eo = -1;
1487 else if (type == OP_CLOSE_SUBEXP)
1489 int reg_num = dfa->nodes[cur_node].opr.idx + 1;
1490 if (reg_num < nmatch)
1492 /* We are at the last node of this sub expression. */
1493 if (pmatch[reg_num].rm_so < cur_idx)
1495 pmatch[reg_num].rm_eo = cur_idx;
1496 /* This is a non-empty match or we are not inside an optional
1497 subexpression. Accept this right away. */
1498 memcpy (prev_idx_match, pmatch, sizeof (regmatch_t) * nmatch);
1502 if (dfa->nodes[cur_node].opt_subexp
1503 && prev_idx_match[reg_num].rm_so != -1)
1504 /* We transited through an empty match for an optional
1505 subexpression, like (a?)*, and this is not the subexp's
1506 first match. Copy back the old content of the registers
1507 so that matches of an inner subexpression are undone as
1508 well, like in ((a?))*. */
1509 memcpy (pmatch, prev_idx_match, sizeof (regmatch_t) * nmatch);
1511 /* We completed a subexpression, but it may be part of
1512 an optional one, so do not update PREV_IDX_MATCH. */
1513 pmatch[reg_num].rm_eo = cur_idx;
1519 /* This function checks the STATE_LOG from the SCTX->last_str_idx to 0
1520 and sift the nodes in each states according to the following rules.
1521 Updated state_log will be wrote to STATE_LOG.
1523 Rules: We throw away the Node `a' in the STATE_LOG[STR_IDX] if...
1524 1. When STR_IDX == MATCH_LAST(the last index in the state_log):
1525 If `a' isn't the LAST_NODE and `a' can't epsilon transit to
1526 the LAST_NODE, we throw away the node `a'.
1527 2. When 0 <= STR_IDX < MATCH_LAST and `a' accepts
1528 string `s' and transit to `b':
1529 i. If 'b' isn't in the STATE_LOG[STR_IDX+strlen('s')], we throw
1531 ii. If 'b' is in the STATE_LOG[STR_IDX+strlen('s')] but 'b' is
1532 thrown away, we throw away the node `a'.
1533 3. When 0 <= STR_IDX < MATCH_LAST and 'a' epsilon transit to 'b':
1534 i. If 'b' isn't in the STATE_LOG[STR_IDX], we throw away the
1536 ii. If 'b' is in the STATE_LOG[STR_IDX] but 'b' is thrown away,
1537 we throw away the node `a'. */
1539 #define STATE_NODE_CONTAINS(state,node) \
1540 ((state) != NULL && re_node_set_contains (&(state)->nodes, node))
1542 static reg_errcode_t
1544 sift_states_backward (re_match_context_t *mctx, re_sift_context_t *sctx)
1548 int str_idx = sctx->last_str_idx;
1549 re_node_set cur_dest;
1552 assert (mctx->state_log != NULL && mctx->state_log[str_idx] != NULL);
1555 /* Build sifted state_log[str_idx]. It has the nodes which can epsilon
1556 transit to the last_node and the last_node itself. */
1557 err = re_node_set_init_1 (&cur_dest, sctx->last_node);
1558 if (BE (err != REG_NOERROR, 0))
1560 err = update_cur_sifted_state (mctx, sctx, str_idx, &cur_dest);
1561 if (BE (err != REG_NOERROR, 0))
1564 /* Then check each states in the state_log. */
1567 /* Update counters. */
1568 null_cnt = (sctx->sifted_states[str_idx] == NULL) ? null_cnt + 1 : 0;
1569 if (null_cnt > mctx->max_mb_elem_len)
1571 memset (sctx->sifted_states, '\0',
1572 sizeof (re_dfastate_t *) * str_idx);
1573 re_node_set_free (&cur_dest);
1576 re_node_set_empty (&cur_dest);
1579 if (mctx->state_log[str_idx])
1581 err = build_sifted_states (mctx, sctx, str_idx, &cur_dest);
1582 if (BE (err != REG_NOERROR, 0))
1586 /* Add all the nodes which satisfy the following conditions:
1587 - It can epsilon transit to a node in CUR_DEST.
1589 And update state_log. */
1590 err = update_cur_sifted_state (mctx, sctx, str_idx, &cur_dest);
1591 if (BE (err != REG_NOERROR, 0))
1596 re_node_set_free (&cur_dest);
1600 static reg_errcode_t
1602 build_sifted_states (re_match_context_t *mctx, re_sift_context_t *sctx,
1603 int str_idx, re_node_set *cur_dest)
1605 re_dfa_t *const dfa = mctx->dfa;
1606 re_node_set *cur_src = &mctx->state_log[str_idx]->non_eps_nodes;
1609 /* Then build the next sifted state.
1610 We build the next sifted state on `cur_dest', and update
1611 `sifted_states[str_idx]' with `cur_dest'.
1613 `cur_dest' is the sifted state from `state_log[str_idx + 1]'.
1614 `cur_src' points the node_set of the old `state_log[str_idx]'
1615 (with the epsilon nodes pre-filtered out). */
1616 for (i = 0; i < cur_src->nelem; i++)
1618 int prev_node = cur_src->elems[i];
1623 re_token_type_t type = dfa->nodes[prev_node].type;
1624 assert (!IS_EPSILON_NODE (type));
1626 #ifdef RE_ENABLE_I18N
1627 /* If the node may accept `multi byte'. */
1628 if (dfa->nodes[prev_node].accept_mb)
1629 naccepted = sift_states_iter_mb (mctx, sctx, prev_node,
1630 str_idx, sctx->last_str_idx);
1631 #endif /* RE_ENABLE_I18N */
1633 /* We don't check backreferences here.
1634 See update_cur_sifted_state(). */
1636 && check_node_accept (mctx, dfa->nodes + prev_node, str_idx)
1637 && STATE_NODE_CONTAINS (sctx->sifted_states[str_idx + 1],
1638 dfa->nexts[prev_node]))
1644 if (sctx->limits.nelem)
1646 int to_idx = str_idx + naccepted;
1647 if (check_dst_limits (mctx, &sctx->limits,
1648 dfa->nexts[prev_node], to_idx,
1649 prev_node, str_idx))
1652 ret = re_node_set_insert (cur_dest, prev_node);
1653 if (BE (ret == -1, 0))
1660 /* Helper functions. */
1662 static reg_errcode_t
1664 clean_state_log_if_needed (re_match_context_t *mctx, int next_state_log_idx)
1666 int top = mctx->state_log_top;
1668 if (next_state_log_idx >= mctx->input.bufs_len
1669 || (next_state_log_idx >= mctx->input.valid_len
1670 && mctx->input.valid_len < mctx->input.len))
1673 err = extend_buffers (mctx);
1674 if (BE (err != REG_NOERROR, 0))
1678 if (top < next_state_log_idx)
1680 memset (mctx->state_log + top + 1, '\0',
1681 sizeof (re_dfastate_t *) * (next_state_log_idx - top));
1682 mctx->state_log_top = next_state_log_idx;
1687 static reg_errcode_t
1689 merge_state_array (re_dfa_t *dfa, re_dfastate_t **dst, re_dfastate_t **src,
1694 for (st_idx = 0; st_idx < num; ++st_idx)
1696 if (dst[st_idx] == NULL)
1697 dst[st_idx] = src[st_idx];
1698 else if (src[st_idx] != NULL)
1700 re_node_set merged_set;
1701 err = re_node_set_init_union (&merged_set, &dst[st_idx]->nodes,
1702 &src[st_idx]->nodes);
1703 if (BE (err != REG_NOERROR, 0))
1705 dst[st_idx] = re_acquire_state (&err, dfa, &merged_set);
1706 re_node_set_free (&merged_set);
1707 if (BE (err != REG_NOERROR, 0))
1714 static reg_errcode_t
1716 update_cur_sifted_state (re_match_context_t *mctx, re_sift_context_t *sctx,
1717 int str_idx, re_node_set *dest_nodes)
1719 re_dfa_t *const dfa = mctx->dfa;
1721 const re_node_set *candidates;
1722 candidates = ((mctx->state_log[str_idx] == NULL) ? NULL
1723 : &mctx->state_log[str_idx]->nodes);
1725 if (dest_nodes->nelem == 0)
1726 sctx->sifted_states[str_idx] = NULL;
1731 /* At first, add the nodes which can epsilon transit to a node in
1733 err = add_epsilon_src_nodes (dfa, dest_nodes, candidates);
1734 if (BE (err != REG_NOERROR, 0))
1737 /* Then, check the limitations in the current sift_context. */
1738 if (sctx->limits.nelem)
1740 err = check_subexp_limits (dfa, dest_nodes, candidates, &sctx->limits,
1741 mctx->bkref_ents, str_idx);
1742 if (BE (err != REG_NOERROR, 0))
1747 sctx->sifted_states[str_idx] = re_acquire_state (&err, dfa, dest_nodes);
1748 if (BE (err != REG_NOERROR, 0))
1752 if (candidates && mctx->state_log[str_idx]->has_backref)
1754 err = sift_states_bkref (mctx, sctx, str_idx, candidates);
1755 if (BE (err != REG_NOERROR, 0))
1761 static reg_errcode_t
1763 add_epsilon_src_nodes (re_dfa_t *dfa, re_node_set *dest_nodes,
1764 const re_node_set *candidates)
1766 reg_errcode_t err = REG_NOERROR;
1769 re_dfastate_t *state = re_acquire_state (&err, dfa, dest_nodes);
1770 if (BE (err != REG_NOERROR, 0))
1773 if (!state->inveclosure.alloc)
1775 err = re_node_set_alloc (&state->inveclosure, dest_nodes->nelem);
1776 if (BE (err != REG_NOERROR, 0))
1778 for (i = 0; i < dest_nodes->nelem; i++)
1779 re_node_set_merge (&state->inveclosure,
1780 dfa->inveclosures + dest_nodes->elems[i]);
1782 return re_node_set_add_intersect (dest_nodes, candidates,
1783 &state->inveclosure);
1786 static reg_errcode_t
1788 sub_epsilon_src_nodes (re_dfa_t *dfa, int node, re_node_set *dest_nodes,
1789 const re_node_set *candidates)
1793 re_node_set *inv_eclosure = dfa->inveclosures + node;
1794 re_node_set except_nodes;
1795 re_node_set_init_empty (&except_nodes);
1796 for (ecl_idx = 0; ecl_idx < inv_eclosure->nelem; ++ecl_idx)
1798 int cur_node = inv_eclosure->elems[ecl_idx];
1799 if (cur_node == node)
1801 if (IS_EPSILON_NODE (dfa->nodes[cur_node].type))
1803 int edst1 = dfa->edests[cur_node].elems[0];
1804 int edst2 = ((dfa->edests[cur_node].nelem > 1)
1805 ? dfa->edests[cur_node].elems[1] : -1);
1806 if ((!re_node_set_contains (inv_eclosure, edst1)
1807 && re_node_set_contains (dest_nodes, edst1))
1809 && !re_node_set_contains (inv_eclosure, edst2)
1810 && re_node_set_contains (dest_nodes, edst2)))
1812 err = re_node_set_add_intersect (&except_nodes, candidates,
1813 dfa->inveclosures + cur_node);
1814 if (BE (err != REG_NOERROR, 0))
1816 re_node_set_free (&except_nodes);
1822 for (ecl_idx = 0; ecl_idx < inv_eclosure->nelem; ++ecl_idx)
1824 int cur_node = inv_eclosure->elems[ecl_idx];
1825 if (!re_node_set_contains (&except_nodes, cur_node))
1827 int idx = re_node_set_contains (dest_nodes, cur_node) - 1;
1828 re_node_set_remove_at (dest_nodes, idx);
1831 re_node_set_free (&except_nodes);
1837 check_dst_limits (re_match_context_t *mctx, re_node_set *limits,
1838 int dst_node, int dst_idx, int src_node, int src_idx)
1840 re_dfa_t *const dfa = mctx->dfa;
1841 int lim_idx, src_pos, dst_pos;
1843 int dst_bkref_idx = search_cur_bkref_entry (mctx, dst_idx);
1844 int src_bkref_idx = search_cur_bkref_entry (mctx, src_idx);
1845 for (lim_idx = 0; lim_idx < limits->nelem; ++lim_idx)
1848 struct re_backref_cache_entry *ent;
1849 ent = mctx->bkref_ents + limits->elems[lim_idx];
1850 subexp_idx = dfa->nodes[ent->node].opr.idx;
1852 dst_pos = check_dst_limits_calc_pos (mctx, limits->elems[lim_idx],
1853 subexp_idx, dst_node, dst_idx,
1855 src_pos = check_dst_limits_calc_pos (mctx, limits->elems[lim_idx],
1856 subexp_idx, src_node, src_idx,
1860 <src> <dst> ( <subexp> )
1861 ( <subexp> ) <src> <dst>
1862 ( <subexp1> <src> <subexp2> <dst> <subexp3> ) */
1863 if (src_pos == dst_pos)
1864 continue; /* This is unrelated limitation. */
1873 check_dst_limits_calc_pos_1 (re_match_context_t *mctx, int boundaries,
1874 int subexp_idx, int from_node, int bkref_idx)
1876 re_dfa_t *const dfa = mctx->dfa;
1877 re_node_set *eclosures = dfa->eclosures + from_node;
1880 /* Else, we are on the boundary: examine the nodes on the epsilon
1882 for (node_idx = 0; node_idx < eclosures->nelem; ++node_idx)
1884 int node = eclosures->elems[node_idx];
1885 switch (dfa->nodes[node].type)
1888 if (bkref_idx != -1)
1890 struct re_backref_cache_entry *ent = mctx->bkref_ents + bkref_idx;
1895 if (ent->node != node)
1898 if (subexp_idx <= 8 * sizeof (ent->eps_reachable_subexps_map)
1899 && !(ent->eps_reachable_subexps_map & (1 << subexp_idx)))
1902 /* Recurse trying to reach the OP_OPEN_SUBEXP and
1903 OP_CLOSE_SUBEXP cases below. But, if the
1904 destination node is the same node as the source
1905 node, don't recurse because it would cause an
1906 infinite loop: a regex that exhibits this behavior
1908 dst = dfa->edests[node].elems[0];
1909 if (dst == from_node)
1913 else /* if (boundaries & 2) */
1918 check_dst_limits_calc_pos_1 (mctx, boundaries, subexp_idx,
1920 if (cpos == -1 /* && (boundaries & 1) */)
1922 if (cpos == 0 && (boundaries & 2))
1925 ent->eps_reachable_subexps_map &= ~(1 << subexp_idx);
1927 while (ent++->more);
1931 case OP_OPEN_SUBEXP:
1932 if ((boundaries & 1) && subexp_idx == dfa->nodes[node].opr.idx)
1936 case OP_CLOSE_SUBEXP:
1937 if ((boundaries & 2) && subexp_idx == dfa->nodes[node].opr.idx)
1946 return (boundaries & 2) ? 1 : 0;
1951 check_dst_limits_calc_pos (re_match_context_t *mctx, int limit, int subexp_idx,
1952 int from_node, int str_idx, int bkref_idx)
1954 struct re_backref_cache_entry *lim = mctx->bkref_ents + limit;
1957 /* If we are outside the range of the subexpression, return -1 or 1. */
1958 if (str_idx < lim->subexp_from)
1961 if (lim->subexp_to < str_idx)
1964 /* If we are within the subexpression, return 0. */
1965 boundaries = (str_idx == lim->subexp_from);
1966 boundaries |= (str_idx == lim->subexp_to) << 1;
1967 if (boundaries == 0)
1970 /* Else, examine epsilon closure. */
1971 return check_dst_limits_calc_pos_1 (mctx, boundaries, subexp_idx,
1972 from_node, bkref_idx);
1975 /* Check the limitations of sub expressions LIMITS, and remove the nodes
1976 which are against limitations from DEST_NODES. */
1978 static reg_errcode_t
1980 check_subexp_limits (re_dfa_t *dfa, re_node_set *dest_nodes,
1981 const re_node_set *candidates, re_node_set *limits,
1982 struct re_backref_cache_entry *bkref_ents, int str_idx)
1985 int node_idx, lim_idx;
1987 for (lim_idx = 0; lim_idx < limits->nelem; ++lim_idx)
1990 struct re_backref_cache_entry *ent;
1991 ent = bkref_ents + limits->elems[lim_idx];
1993 if (str_idx <= ent->subexp_from || ent->str_idx < str_idx)
1994 continue; /* This is unrelated limitation. */
1996 subexp_idx = dfa->nodes[ent->node].opr.idx;
1997 if (ent->subexp_to == str_idx)
2001 for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx)
2003 int node = dest_nodes->elems[node_idx];
2004 re_token_type_t type = dfa->nodes[node].type;
2005 if (type == OP_OPEN_SUBEXP
2006 && subexp_idx == dfa->nodes[node].opr.idx)
2008 else if (type == OP_CLOSE_SUBEXP
2009 && subexp_idx == dfa->nodes[node].opr.idx)
2013 /* Check the limitation of the open subexpression. */
2014 /* Note that (ent->subexp_to = str_idx != ent->subexp_from). */
2017 err = sub_epsilon_src_nodes (dfa, ops_node, dest_nodes,
2019 if (BE (err != REG_NOERROR, 0))
2023 /* Check the limitation of the close subexpression. */
2025 for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx)
2027 int node = dest_nodes->elems[node_idx];
2028 if (!re_node_set_contains (dfa->inveclosures + node,
2030 && !re_node_set_contains (dfa->eclosures + node,
2033 /* It is against this limitation.
2034 Remove it form the current sifted state. */
2035 err = sub_epsilon_src_nodes (dfa, node, dest_nodes,
2037 if (BE (err != REG_NOERROR, 0))
2043 else /* (ent->subexp_to != str_idx) */
2045 for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx)
2047 int node = dest_nodes->elems[node_idx];
2048 re_token_type_t type = dfa->nodes[node].type;
2049 if (type == OP_CLOSE_SUBEXP || type == OP_OPEN_SUBEXP)
2051 if (subexp_idx != dfa->nodes[node].opr.idx)
2053 /* It is against this limitation.
2054 Remove it form the current sifted state. */
2055 err = sub_epsilon_src_nodes (dfa, node, dest_nodes,
2057 if (BE (err != REG_NOERROR, 0))
2066 static reg_errcode_t
2068 sift_states_bkref (re_match_context_t *mctx, re_sift_context_t *sctx,
2069 int str_idx, const re_node_set *candidates)
2071 re_dfa_t *const dfa = mctx->dfa;
2074 re_sift_context_t local_sctx;
2075 int first_idx = search_cur_bkref_entry (mctx, str_idx);
2077 if (first_idx == -1)
2080 local_sctx.sifted_states = NULL; /* Mark that it hasn't been initialized. */
2082 for (node_idx = 0; node_idx < candidates->nelem; ++node_idx)
2085 re_token_type_t type;
2086 struct re_backref_cache_entry *entry;
2087 node = candidates->elems[node_idx];
2088 type = dfa->nodes[node].type;
2089 /* Avoid infinite loop for the REs like "()\1+". */
2090 if (node == sctx->last_node && str_idx == sctx->last_str_idx)
2092 if (type != OP_BACK_REF)
2095 entry = mctx->bkref_ents + first_idx;
2096 enabled_idx = first_idx;
2099 int subexp_len, to_idx, dst_node, ret;
2100 re_dfastate_t *cur_state;
2102 if (entry->node != node)
2104 subexp_len = entry->subexp_to - entry->subexp_from;
2105 to_idx = str_idx + subexp_len;
2106 dst_node = (subexp_len ? dfa->nexts[node]
2107 : dfa->edests[node].elems[0]);
2109 if (to_idx > sctx->last_str_idx
2110 || sctx->sifted_states[to_idx] == NULL
2111 || !STATE_NODE_CONTAINS (sctx->sifted_states[to_idx], dst_node)
2112 || check_dst_limits (mctx, &sctx->limits, node,
2113 str_idx, dst_node, to_idx))
2116 if (local_sctx.sifted_states == NULL)
2119 err = re_node_set_init_copy (&local_sctx.limits, &sctx->limits);
2120 if (BE (err != REG_NOERROR, 0))
2123 local_sctx.last_node = node;
2124 local_sctx.last_str_idx = str_idx;
2125 ret = re_node_set_insert (&local_sctx.limits, enabled_idx);
2126 if (BE (ret < 0, 0))
2131 cur_state = local_sctx.sifted_states[str_idx];
2132 err = sift_states_backward (mctx, &local_sctx);
2133 if (BE (err != REG_NOERROR, 0))
2135 if (sctx->limited_states != NULL)
2137 err = merge_state_array (dfa, sctx->limited_states,
2138 local_sctx.sifted_states,
2140 if (BE (err != REG_NOERROR, 0))
2143 local_sctx.sifted_states[str_idx] = cur_state;
2144 re_node_set_remove (&local_sctx.limits, enabled_idx);
2146 /* mctx->bkref_ents may have changed, reload the pointer. */
2147 entry = mctx->bkref_ents + enabled_idx;
2149 while (enabled_idx++, entry++->more);
2153 if (local_sctx.sifted_states != NULL)
2155 re_node_set_free (&local_sctx.limits);
2162 #ifdef RE_ENABLE_I18N
2165 sift_states_iter_mb (const re_match_context_t *mctx, re_sift_context_t *sctx,
2166 int node_idx, int str_idx, int max_str_idx)
2168 re_dfa_t *const dfa = mctx->dfa;
2170 /* Check the node can accept `multi byte'. */
2171 naccepted = check_node_accept_bytes (dfa, node_idx, &mctx->input, str_idx);
2172 if (naccepted > 0 && str_idx + naccepted <= max_str_idx &&
2173 !STATE_NODE_CONTAINS (sctx->sifted_states[str_idx + naccepted],
2174 dfa->nexts[node_idx]))
2175 /* The node can't accept the `multi byte', or the
2176 destination was already thrown away, then the node
2177 could't accept the current input `multi byte'. */
2179 /* Otherwise, it is sure that the node could accept
2180 `naccepted' bytes input. */
2183 #endif /* RE_ENABLE_I18N */
2186 /* Functions for state transition. */
2188 /* Return the next state to which the current state STATE will transit by
2189 accepting the current input byte, and update STATE_LOG if necessary.
2190 If STATE can accept a multibyte char/collating element/back reference
2191 update the destination of STATE_LOG. */
2193 static re_dfastate_t *
2195 transit_state (reg_errcode_t *err, re_match_context_t *mctx,
2196 re_dfastate_t *state)
2198 re_dfastate_t **trtable;
2201 #ifdef RE_ENABLE_I18N
2202 /* If the current state can accept multibyte. */
2203 if (BE (state->accept_mb, 0))
2205 *err = transit_state_mb (mctx, state);
2206 if (BE (*err != REG_NOERROR, 0))
2209 #endif /* RE_ENABLE_I18N */
2211 /* Then decide the next state with the single byte. */
2214 /* don't use transition table */
2215 return transit_state_sb (err, mctx, state);
2218 /* Use transition table */
2219 ch = re_string_fetch_byte (&mctx->input);
2222 trtable = state->trtable;
2223 if (BE (trtable != NULL, 1))
2226 trtable = state->word_trtable;
2227 if (BE (trtable != NULL, 1))
2229 unsigned int context;
2231 = re_string_context_at (&mctx->input,
2232 re_string_cur_idx (&mctx->input) - 1,
2234 if (IS_WORD_CONTEXT (context))
2235 return trtable[ch + SBC_MAX];
2240 if (!build_trtable (mctx->dfa, state))
2246 /* Retry, we now have a transition table. */
2250 /* Update the state_log if we need */
2253 merge_state_with_log (reg_errcode_t *err, re_match_context_t *mctx,
2254 re_dfastate_t *next_state)
2256 re_dfa_t *const dfa = mctx->dfa;
2257 int cur_idx = re_string_cur_idx (&mctx->input);
2259 if (cur_idx > mctx->state_log_top)
2261 mctx->state_log[cur_idx] = next_state;
2262 mctx->state_log_top = cur_idx;
2264 else if (mctx->state_log[cur_idx] == 0)
2266 mctx->state_log[cur_idx] = next_state;
2270 re_dfastate_t *pstate;
2271 unsigned int context;
2272 re_node_set next_nodes, *log_nodes, *table_nodes = NULL;
2273 /* If (state_log[cur_idx] != 0), it implies that cur_idx is
2274 the destination of a multibyte char/collating element/
2275 back reference. Then the next state is the union set of
2276 these destinations and the results of the transition table. */
2277 pstate = mctx->state_log[cur_idx];
2278 log_nodes = pstate->entrance_nodes;
2279 if (next_state != NULL)
2281 table_nodes = next_state->entrance_nodes;
2282 *err = re_node_set_init_union (&next_nodes, table_nodes,
2284 if (BE (*err != REG_NOERROR, 0))
2288 next_nodes = *log_nodes;
2289 /* Note: We already add the nodes of the initial state,
2290 then we don't need to add them here. */
2292 context = re_string_context_at (&mctx->input,
2293 re_string_cur_idx (&mctx->input) - 1,
2295 next_state = mctx->state_log[cur_idx]
2296 = re_acquire_state_context (err, dfa, &next_nodes, context);
2297 /* We don't need to check errors here, since the return value of
2298 this function is next_state and ERR is already set. */
2300 if (table_nodes != NULL)
2301 re_node_set_free (&next_nodes);
2304 if (BE (dfa->nbackref, 0) && next_state != NULL)
2306 /* Check OP_OPEN_SUBEXP in the current state in case that we use them
2307 later. We must check them here, since the back references in the
2308 next state might use them. */
2309 *err = check_subexp_matching_top (mctx, &next_state->nodes,
2311 if (BE (*err != REG_NOERROR, 0))
2314 /* If the next state has back references. */
2315 if (next_state->has_backref)
2317 *err = transit_state_bkref (mctx, &next_state->nodes);
2318 if (BE (*err != REG_NOERROR, 0))
2320 next_state = mctx->state_log[cur_idx];
2327 /* Skip bytes in the input that correspond to part of a
2328 multi-byte match, then look in the log for a state
2329 from which to restart matching. */
2330 static re_dfastate_t *
2332 find_recover_state (reg_errcode_t *err, re_match_context_t *mctx)
2334 re_dfastate_t *cur_state = NULL;
2337 int max = mctx->state_log_top;
2338 int cur_str_idx = re_string_cur_idx (&mctx->input);
2342 if (++cur_str_idx > max)
2344 re_string_skip_bytes (&mctx->input, 1);
2346 while (mctx->state_log[cur_str_idx] == NULL);
2348 cur_state = merge_state_with_log (err, mctx, NULL);
2350 while (*err == REG_NOERROR && cur_state == NULL);
2354 /* Helper functions for transit_state. */
2356 /* From the node set CUR_NODES, pick up the nodes whose types are
2357 OP_OPEN_SUBEXP and which have corresponding back references in the regular
2358 expression. And register them to use them later for evaluating the
2359 correspoding back references. */
2361 static reg_errcode_t
2363 check_subexp_matching_top (re_match_context_t *mctx, re_node_set *cur_nodes,
2366 re_dfa_t *const dfa = mctx->dfa;
2370 /* TODO: This isn't efficient.
2371 Because there might be more than one nodes whose types are
2372 OP_OPEN_SUBEXP and whose index is SUBEXP_IDX, we must check all
2375 for (node_idx = 0; node_idx < cur_nodes->nelem; ++node_idx)
2377 int node = cur_nodes->elems[node_idx];
2378 if (dfa->nodes[node].type == OP_OPEN_SUBEXP
2379 && dfa->nodes[node].opr.idx < (8 * sizeof (dfa->used_bkref_map))
2380 && dfa->used_bkref_map & (1 << dfa->nodes[node].opr.idx))
2382 err = match_ctx_add_subtop (mctx, node, str_idx);
2383 if (BE (err != REG_NOERROR, 0))
2391 /* Return the next state to which the current state STATE will transit by
2392 accepting the current input byte. */
2394 static re_dfastate_t *
2395 transit_state_sb (err, mctx, state)
2397 re_match_context_t *mctx;
2398 re_dfastate_t *state;
2400 re_dfa_t *const dfa = mctx->dfa;
2401 re_node_set next_nodes;
2402 re_dfastate_t *next_state;
2403 int node_cnt, cur_str_idx = re_string_cur_idx (&mctx->input);
2404 unsigned int context;
2406 *err = re_node_set_alloc (&next_nodes, state->nodes.nelem + 1);
2407 if (BE (*err != REG_NOERROR, 0))
2409 for (node_cnt = 0; node_cnt < state->nodes.nelem; ++node_cnt)
2411 int cur_node = state->nodes.elems[node_cnt];
2412 if (check_node_accept (mctx, dfa->nodes + cur_node, cur_str_idx))
2414 *err = re_node_set_merge (&next_nodes,
2415 dfa->eclosures + dfa->nexts[cur_node]);
2416 if (BE (*err != REG_NOERROR, 0))
2418 re_node_set_free (&next_nodes);
2423 context = re_string_context_at (&mctx->input, cur_str_idx, mctx->eflags);
2424 next_state = re_acquire_state_context (err, dfa, &next_nodes, context);
2425 /* We don't need to check errors here, since the return value of
2426 this function is next_state and ERR is already set. */
2428 re_node_set_free (&next_nodes);
2429 re_string_skip_bytes (&mctx->input, 1);
2434 #ifdef RE_ENABLE_I18N
2435 static reg_errcode_t
2437 transit_state_mb (re_match_context_t *mctx, re_dfastate_t *pstate)
2439 re_dfa_t *const dfa = mctx->dfa;
2443 for (i = 0; i < pstate->nodes.nelem; ++i)
2445 re_node_set dest_nodes, *new_nodes;
2446 int cur_node_idx = pstate->nodes.elems[i];
2447 int naccepted, dest_idx;
2448 unsigned int context;
2449 re_dfastate_t *dest_state;
2451 if (!dfa->nodes[cur_node_idx].accept_mb)
2454 if (dfa->nodes[cur_node_idx].constraint)
2456 context = re_string_context_at (&mctx->input,
2457 re_string_cur_idx (&mctx->input),
2459 if (NOT_SATISFY_NEXT_CONSTRAINT (dfa->nodes[cur_node_idx].constraint,
2464 /* How many bytes the node can accept? */
2465 naccepted = check_node_accept_bytes (dfa, cur_node_idx, &mctx->input,
2466 re_string_cur_idx (&mctx->input));
2470 /* The node can accepts `naccepted' bytes. */
2471 dest_idx = re_string_cur_idx (&mctx->input) + naccepted;
2472 mctx->max_mb_elem_len = ((mctx->max_mb_elem_len < naccepted) ? naccepted
2473 : mctx->max_mb_elem_len);
2474 err = clean_state_log_if_needed (mctx, dest_idx);
2475 if (BE (err != REG_NOERROR, 0))
2478 assert (dfa->nexts[cur_node_idx] != -1);
2480 new_nodes = dfa->eclosures + dfa->nexts[cur_node_idx];
2482 dest_state = mctx->state_log[dest_idx];
2483 if (dest_state == NULL)
2484 dest_nodes = *new_nodes;
2487 err = re_node_set_init_union (&dest_nodes,
2488 dest_state->entrance_nodes, new_nodes);
2489 if (BE (err != REG_NOERROR, 0))
2492 context = re_string_context_at (&mctx->input, dest_idx - 1, mctx->eflags);
2493 mctx->state_log[dest_idx]
2494 = re_acquire_state_context (&err, dfa, &dest_nodes, context);
2495 if (dest_state != NULL)
2496 re_node_set_free (&dest_nodes);
2497 if (BE (mctx->state_log[dest_idx] == NULL && err != REG_NOERROR, 0))
2502 #endif /* RE_ENABLE_I18N */
2504 static reg_errcode_t
2506 transit_state_bkref (re_match_context_t *mctx, const re_node_set *nodes)
2508 re_dfa_t *const dfa = mctx->dfa;
2511 int cur_str_idx = re_string_cur_idx (&mctx->input);
2513 for (i = 0; i < nodes->nelem; ++i)
2515 int dest_str_idx, prev_nelem, bkc_idx;
2516 int node_idx = nodes->elems[i];
2517 unsigned int context;
2518 const re_token_t *node = dfa->nodes + node_idx;
2519 re_node_set *new_dest_nodes;
2521 /* Check whether `node' is a backreference or not. */
2522 if (node->type != OP_BACK_REF)
2525 if (node->constraint)
2527 context = re_string_context_at (&mctx->input, cur_str_idx,
2529 if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context))
2533 /* `node' is a backreference.
2534 Check the substring which the substring matched. */
2535 bkc_idx = mctx->nbkref_ents;
2536 err = get_subexp (mctx, node_idx, cur_str_idx);
2537 if (BE (err != REG_NOERROR, 0))
2540 /* And add the epsilon closures (which is `new_dest_nodes') of
2541 the backreference to appropriate state_log. */
2543 assert (dfa->nexts[node_idx] != -1);
2545 for (; bkc_idx < mctx->nbkref_ents; ++bkc_idx)
2548 re_dfastate_t *dest_state;
2549 struct re_backref_cache_entry *bkref_ent;
2550 bkref_ent = mctx->bkref_ents + bkc_idx;
2551 if (bkref_ent->node != node_idx || bkref_ent->str_idx != cur_str_idx)
2553 subexp_len = bkref_ent->subexp_to - bkref_ent->subexp_from;
2554 new_dest_nodes = (subexp_len == 0
2555 ? dfa->eclosures + dfa->edests[node_idx].elems[0]
2556 : dfa->eclosures + dfa->nexts[node_idx]);
2557 dest_str_idx = (cur_str_idx + bkref_ent->subexp_to
2558 - bkref_ent->subexp_from);
2559 context = re_string_context_at (&mctx->input, dest_str_idx - 1,
2561 dest_state = mctx->state_log[dest_str_idx];
2562 prev_nelem = ((mctx->state_log[cur_str_idx] == NULL) ? 0
2563 : mctx->state_log[cur_str_idx]->nodes.nelem);
2564 /* Add `new_dest_node' to state_log. */
2565 if (dest_state == NULL)
2567 mctx->state_log[dest_str_idx]
2568 = re_acquire_state_context (&err, dfa, new_dest_nodes,
2570 if (BE (mctx->state_log[dest_str_idx] == NULL
2571 && err != REG_NOERROR, 0))
2576 re_node_set dest_nodes;
2577 err = re_node_set_init_union (&dest_nodes,
2578 dest_state->entrance_nodes,
2580 if (BE (err != REG_NOERROR, 0))
2582 re_node_set_free (&dest_nodes);
2585 mctx->state_log[dest_str_idx]
2586 = re_acquire_state_context (&err, dfa, &dest_nodes, context);
2587 re_node_set_free (&dest_nodes);
2588 if (BE (mctx->state_log[dest_str_idx] == NULL
2589 && err != REG_NOERROR, 0))
2592 /* We need to check recursively if the backreference can epsilon
2595 && mctx->state_log[cur_str_idx]->nodes.nelem > prev_nelem)
2597 err = check_subexp_matching_top (mctx, new_dest_nodes,
2599 if (BE (err != REG_NOERROR, 0))
2601 err = transit_state_bkref (mctx, new_dest_nodes);
2602 if (BE (err != REG_NOERROR, 0))
2612 /* Enumerate all the candidates which the backreference BKREF_NODE can match
2613 at BKREF_STR_IDX, and register them by match_ctx_add_entry().
2614 Note that we might collect inappropriate candidates here.
2615 However, the cost of checking them strictly here is too high, then we
2616 delay these checking for prune_impossible_nodes(). */
2618 static reg_errcode_t
2620 get_subexp (re_match_context_t *mctx, int bkref_node, int bkref_str_idx)
2622 re_dfa_t *const dfa = mctx->dfa;
2623 int subexp_num, sub_top_idx;
2624 const char *buf = (const char *) re_string_get_buffer (&mctx->input);
2625 /* Return if we have already checked BKREF_NODE at BKREF_STR_IDX. */
2626 int cache_idx = search_cur_bkref_entry (mctx, bkref_str_idx);
2627 if (cache_idx != -1)
2629 const struct re_backref_cache_entry *entry = mctx->bkref_ents + cache_idx;
2631 if (entry->node == bkref_node)
2632 return REG_NOERROR; /* We already checked it. */
2633 while (entry++->more);
2636 subexp_num = dfa->nodes[bkref_node].opr.idx;
2638 /* For each sub expression */
2639 for (sub_top_idx = 0; sub_top_idx < mctx->nsub_tops; ++sub_top_idx)
2642 re_sub_match_top_t *sub_top = mctx->sub_tops[sub_top_idx];
2643 re_sub_match_last_t *sub_last;
2644 int sub_last_idx, sl_str, bkref_str_off;
2646 if (dfa->nodes[sub_top->node].opr.idx != subexp_num)
2647 continue; /* It isn't related. */
2649 sl_str = sub_top->str_idx;
2650 bkref_str_off = bkref_str_idx;
2651 /* At first, check the last node of sub expressions we already
2653 for (sub_last_idx = 0; sub_last_idx < sub_top->nlasts; ++sub_last_idx)
2656 sub_last = sub_top->lasts[sub_last_idx];
2657 sl_str_diff = sub_last->str_idx - sl_str;
2658 /* The matched string by the sub expression match with the substring
2659 at the back reference? */
2660 if (sl_str_diff > 0)
2662 if (BE (bkref_str_off + sl_str_diff > mctx->input.valid_len, 0))
2664 /* Not enough chars for a successful match. */
2665 if (bkref_str_off + sl_str_diff > mctx->input.len)
2668 err = clean_state_log_if_needed (mctx,
2671 if (BE (err != REG_NOERROR, 0))
2673 buf = (const char *) re_string_get_buffer (&mctx->input);
2675 if (memcmp (buf + bkref_str_off, buf + sl_str, sl_str_diff) != 0)
2676 break; /* We don't need to search this sub expression any more. */
2678 bkref_str_off += sl_str_diff;
2679 sl_str += sl_str_diff;
2680 err = get_subexp_sub (mctx, sub_top, sub_last, bkref_node,
2683 /* Reload buf, since the preceding call might have reallocated
2685 buf = (const char *) re_string_get_buffer (&mctx->input);
2687 if (err == REG_NOMATCH)
2689 if (BE (err != REG_NOERROR, 0))
2693 if (sub_last_idx < sub_top->nlasts)
2695 if (sub_last_idx > 0)
2697 /* Then, search for the other last nodes of the sub expression. */
2698 for (; sl_str <= bkref_str_idx; ++sl_str)
2700 int cls_node, sl_str_off;
2701 const re_node_set *nodes;
2702 sl_str_off = sl_str - sub_top->str_idx;
2703 /* The matched string by the sub expression match with the substring
2704 at the back reference? */
2707 if (BE (bkref_str_off >= mctx->input.valid_len, 0))
2709 /* If we are at the end of the input, we cannot match. */
2710 if (bkref_str_off >= mctx->input.len)
2713 err = extend_buffers (mctx);
2714 if (BE (err != REG_NOERROR, 0))
2717 buf = (const char *) re_string_get_buffer (&mctx->input);
2719 if (buf [bkref_str_off++] != buf[sl_str - 1])
2720 break; /* We don't need to search this sub expression
2723 if (mctx->state_log[sl_str] == NULL)
2725 /* Does this state have a ')' of the sub expression? */
2726 nodes = &mctx->state_log[sl_str]->nodes;
2727 cls_node = find_subexp_node (dfa, nodes, subexp_num, OP_CLOSE_SUBEXP);
2730 if (sub_top->path == NULL)
2732 sub_top->path = re_calloc (state_array_t,
2733 sl_str - sub_top->str_idx + 1);
2734 if (sub_top->path == NULL)
2737 /* Can the OP_OPEN_SUBEXP node arrive the OP_CLOSE_SUBEXP node
2738 in the current context? */
2739 err = check_arrival (mctx, sub_top->path, sub_top->node,
2740 sub_top->str_idx, cls_node, sl_str, OP_CLOSE_SUBEXP);
2741 if (err == REG_NOMATCH)
2743 if (BE (err != REG_NOERROR, 0))
2745 sub_last = match_ctx_add_sublast (sub_top, cls_node, sl_str);
2746 if (BE (sub_last == NULL, 0))
2748 err = get_subexp_sub (mctx, sub_top, sub_last, bkref_node,
2750 if (err == REG_NOMATCH)
2757 /* Helper functions for get_subexp(). */
2759 /* Check SUB_LAST can arrive to the back reference BKREF_NODE at BKREF_STR.
2760 If it can arrive, register the sub expression expressed with SUB_TOP
2763 static reg_errcode_t
2765 get_subexp_sub (re_match_context_t *mctx, const re_sub_match_top_t *sub_top,
2766 re_sub_match_last_t *sub_last, int bkref_node, int bkref_str)
2770 /* Can the subexpression arrive the back reference? */
2771 err = check_arrival (mctx, &sub_last->path, sub_last->node,
2772 sub_last->str_idx, bkref_node, bkref_str, OP_OPEN_SUBEXP);
2773 if (err != REG_NOERROR)
2775 err = match_ctx_add_entry (mctx, bkref_node, bkref_str, sub_top->str_idx,
2777 if (BE (err != REG_NOERROR, 0))
2779 to_idx = bkref_str + sub_last->str_idx - sub_top->str_idx;
2780 return clean_state_log_if_needed (mctx, to_idx);
2783 /* Find the first node which is '(' or ')' and whose index is SUBEXP_IDX.
2784 Search '(' if FL_OPEN, or search ')' otherwise.
2785 TODO: This function isn't efficient...
2786 Because there might be more than one nodes whose types are
2787 OP_OPEN_SUBEXP and whose index is SUBEXP_IDX, we must check all
2793 find_subexp_node (const re_dfa_t *dfa, const re_node_set *nodes,
2794 int subexp_idx, int type)
2797 for (cls_idx = 0; cls_idx < nodes->nelem; ++cls_idx)
2799 int cls_node = nodes->elems[cls_idx];
2800 const re_token_t *node = dfa->nodes + cls_node;
2801 if (node->type == type
2802 && node->opr.idx == subexp_idx)
2808 /* Check whether the node TOP_NODE at TOP_STR can arrive to the node
2809 LAST_NODE at LAST_STR. We record the path onto PATH since it will be
2811 Return REG_NOERROR if it can arrive, or REG_NOMATCH otherwise. */
2813 static reg_errcode_t
2815 check_arrival (re_match_context_t *mctx, state_array_t *path,
2816 int top_node, int top_str, int last_node, int last_str,
2819 re_dfa_t *const dfa = mctx->dfa;
2821 int subexp_num, backup_cur_idx, str_idx, null_cnt;
2822 re_dfastate_t *cur_state = NULL;
2823 re_node_set *cur_nodes, next_nodes;
2824 re_dfastate_t **backup_state_log;
2825 unsigned int context;
2827 subexp_num = dfa->nodes[top_node].opr.idx;
2828 /* Extend the buffer if we need. */
2829 if (BE (path->alloc < last_str + mctx->max_mb_elem_len + 1, 0))
2831 re_dfastate_t **new_array;
2832 int old_alloc = path->alloc;
2833 path->alloc += last_str + mctx->max_mb_elem_len + 1;
2834 new_array = re_realloc (path->array, re_dfastate_t *, path->alloc);
2835 if (new_array == NULL)
2837 path->alloc = old_alloc;
2840 path->array = new_array;
2841 memset (new_array + old_alloc, '\0',
2842 sizeof (re_dfastate_t *) * (path->alloc - old_alloc));
2845 str_idx = path->next_idx == 0 ? top_str : path->next_idx;
2847 /* Temporary modify MCTX. */
2848 backup_state_log = mctx->state_log;
2849 backup_cur_idx = mctx->input.cur_idx;
2850 mctx->state_log = path->array;
2851 mctx->input.cur_idx = str_idx;
2853 /* Setup initial node set. */
2854 context = re_string_context_at (&mctx->input, str_idx - 1, mctx->eflags);
2855 if (str_idx == top_str)
2857 err = re_node_set_init_1 (&next_nodes, top_node);
2858 if (BE (err != REG_NOERROR, 0))
2860 err = check_arrival_expand_ecl (dfa, &next_nodes, subexp_num, type);
2861 if (BE (err != REG_NOERROR, 0))
2863 re_node_set_free (&next_nodes);
2869 cur_state = mctx->state_log[str_idx];
2870 if (cur_state && cur_state->has_backref)
2872 err = re_node_set_init_copy (&next_nodes, &cur_state->nodes);
2873 if (BE ( err != REG_NOERROR, 0))
2877 re_node_set_init_empty (&next_nodes);
2879 if (str_idx == top_str || (cur_state && cur_state->has_backref))
2881 if (next_nodes.nelem)
2883 err = expand_bkref_cache (mctx, &next_nodes, str_idx,
2885 if (BE ( err != REG_NOERROR, 0))
2887 re_node_set_free (&next_nodes);
2891 cur_state = re_acquire_state_context (&err, dfa, &next_nodes, context);
2892 if (BE (cur_state == NULL && err != REG_NOERROR, 0))
2894 re_node_set_free (&next_nodes);
2897 mctx->state_log[str_idx] = cur_state;
2900 for (null_cnt = 0; str_idx < last_str && null_cnt <= mctx->max_mb_elem_len;)
2902 re_node_set_empty (&next_nodes);
2903 if (mctx->state_log[str_idx + 1])
2905 err = re_node_set_merge (&next_nodes,
2906 &mctx->state_log[str_idx + 1]->nodes);
2907 if (BE (err != REG_NOERROR, 0))
2909 re_node_set_free (&next_nodes);
2915 err = check_arrival_add_next_nodes (mctx, str_idx,
2916 &cur_state->non_eps_nodes, &next_nodes);
2917 if (BE (err != REG_NOERROR, 0))
2919 re_node_set_free (&next_nodes);
2924 if (next_nodes.nelem)
2926 err = check_arrival_expand_ecl (dfa, &next_nodes, subexp_num, type);
2927 if (BE (err != REG_NOERROR, 0))
2929 re_node_set_free (&next_nodes);
2932 err = expand_bkref_cache (mctx, &next_nodes, str_idx,
2934 if (BE ( err != REG_NOERROR, 0))
2936 re_node_set_free (&next_nodes);
2940 context = re_string_context_at (&mctx->input, str_idx - 1, mctx->eflags);
2941 cur_state = re_acquire_state_context (&err, dfa, &next_nodes, context);
2942 if (BE (cur_state == NULL && err != REG_NOERROR, 0))
2944 re_node_set_free (&next_nodes);
2947 mctx->state_log[str_idx] = cur_state;
2948 null_cnt = cur_state == NULL ? null_cnt + 1 : 0;
2950 re_node_set_free (&next_nodes);
2951 cur_nodes = (mctx->state_log[last_str] == NULL ? NULL
2952 : &mctx->state_log[last_str]->nodes);
2953 path->next_idx = str_idx;
2956 mctx->state_log = backup_state_log;
2957 mctx->input.cur_idx = backup_cur_idx;
2959 /* Then check the current node set has the node LAST_NODE. */
2960 if (cur_nodes != NULL && re_node_set_contains (cur_nodes, last_node))
2966 /* Helper functions for check_arrival. */
2968 /* Calculate the destination nodes of CUR_NODES at STR_IDX, and append them
2970 TODO: This function is similar to the functions transit_state*(),
2971 however this function has many additional works.
2972 Can't we unify them? */
2974 static reg_errcode_t
2976 check_arrival_add_next_nodes (re_match_context_t *mctx, int str_idx,
2977 re_node_set *cur_nodes,
2978 re_node_set *next_nodes)
2980 re_dfa_t *const dfa = mctx->dfa;
2984 re_node_set union_set;
2985 re_node_set_init_empty (&union_set);
2986 for (cur_idx = 0; cur_idx < cur_nodes->nelem; ++cur_idx)
2989 int cur_node = cur_nodes->elems[cur_idx];
2991 re_token_type_t type = dfa->nodes[cur_node].type;
2992 assert (!IS_EPSILON_NODE (type));
2994 #ifdef RE_ENABLE_I18N
2995 /* If the node may accept `multi byte'. */
2996 if (dfa->nodes[cur_node].accept_mb)
2998 naccepted = check_node_accept_bytes (dfa, cur_node, &mctx->input,
3002 re_dfastate_t *dest_state;
3003 int next_node = dfa->nexts[cur_node];
3004 int next_idx = str_idx + naccepted;
3005 dest_state = mctx->state_log[next_idx];
3006 re_node_set_empty (&union_set);
3009 err = re_node_set_merge (&union_set, &dest_state->nodes);
3010 if (BE (err != REG_NOERROR, 0))
3012 re_node_set_free (&union_set);
3016 result = re_node_set_insert (&union_set, next_node);
3017 if (BE (result < 0, 0))
3019 re_node_set_free (&union_set);
3022 mctx->state_log[next_idx] = re_acquire_state (&err, dfa,
3024 if (BE (mctx->state_log[next_idx] == NULL
3025 && err != REG_NOERROR, 0))
3027 re_node_set_free (&union_set);
3032 #endif /* RE_ENABLE_I18N */
3034 || check_node_accept (mctx, dfa->nodes + cur_node, str_idx))
3036 result = re_node_set_insert (next_nodes, dfa->nexts[cur_node]);
3037 if (BE (result < 0, 0))
3039 re_node_set_free (&union_set);
3044 re_node_set_free (&union_set);
3048 /* For all the nodes in CUR_NODES, add the epsilon closures of them to
3049 CUR_NODES, however exclude the nodes which are:
3050 - inside the sub expression whose number is EX_SUBEXP, if FL_OPEN.
3051 - out of the sub expression whose number is EX_SUBEXP, if !FL_OPEN.
3054 static reg_errcode_t
3056 check_arrival_expand_ecl (re_dfa_t *dfa, re_node_set *cur_nodes,
3057 int ex_subexp, int type)
3060 int idx, outside_node;
3061 re_node_set new_nodes;
3063 assert (cur_nodes->nelem);
3065 err = re_node_set_alloc (&new_nodes, cur_nodes->nelem);
3066 if (BE (err != REG_NOERROR, 0))
3068 /* Create a new node set NEW_NODES with the nodes which are epsilon
3069 closures of the node in CUR_NODES. */
3071 for (idx = 0; idx < cur_nodes->nelem; ++idx)
3073 int cur_node = cur_nodes->elems[idx];
3074 re_node_set *eclosure = dfa->eclosures + cur_node;
3075 outside_node = find_subexp_node (dfa, eclosure, ex_subexp, type);
3076 if (outside_node == -1)
3078 /* There are no problematic nodes, just merge them. */
3079 err = re_node_set_merge (&new_nodes, eclosure);
3080 if (BE (err != REG_NOERROR, 0))
3082 re_node_set_free (&new_nodes);
3088 /* There are problematic nodes, re-calculate incrementally. */
3089 err = check_arrival_expand_ecl_sub (dfa, &new_nodes, cur_node,
3091 if (BE (err != REG_NOERROR, 0))
3093 re_node_set_free (&new_nodes);
3098 re_node_set_free (cur_nodes);
3099 *cur_nodes = new_nodes;
3103 /* Helper function for check_arrival_expand_ecl.
3104 Check incrementally the epsilon closure of TARGET, and if it isn't
3105 problematic append it to DST_NODES. */
3107 static reg_errcode_t
3109 check_arrival_expand_ecl_sub (re_dfa_t *dfa, re_node_set *dst_nodes,
3110 int target, int ex_subexp, int type)
3113 for (cur_node = target; !re_node_set_contains (dst_nodes, cur_node);)
3117 if (dfa->nodes[cur_node].type == type
3118 && dfa->nodes[cur_node].opr.idx == ex_subexp)
3120 if (type == OP_CLOSE_SUBEXP)
3122 err = re_node_set_insert (dst_nodes, cur_node);
3123 if (BE (err == -1, 0))
3128 err = re_node_set_insert (dst_nodes, cur_node);
3129 if (BE (err == -1, 0))
3131 if (dfa->edests[cur_node].nelem == 0)
3133 if (dfa->edests[cur_node].nelem == 2)
3136 check_arrival_expand_ecl_sub (dfa, dst_nodes,
3137 dfa->edests[cur_node].elems[1],
3139 if (BE (ret != REG_NOERROR, 0))
3142 cur_node = dfa->edests[cur_node].elems[0];
3148 /* For all the back references in the current state, calculate the
3149 destination of the back references by the appropriate entry
3150 in MCTX->BKREF_ENTS. */
3152 static reg_errcode_t
3154 expand_bkref_cache (re_match_context_t *mctx, re_node_set *cur_nodes,
3155 int cur_str, int subexp_num, int type)
3157 re_dfa_t *const dfa = mctx->dfa;
3159 int cache_idx_start = search_cur_bkref_entry (mctx, cur_str);
3160 struct re_backref_cache_entry *ent;
3162 if (cache_idx_start == -1)
3166 ent = mctx->bkref_ents + cache_idx_start;
3169 int to_idx, next_node;
3171 /* Is this entry ENT is appropriate? */
3172 if (!re_node_set_contains (cur_nodes, ent->node))
3175 to_idx = cur_str + ent->subexp_to - ent->subexp_from;
3176 /* Calculate the destination of the back reference, and append it
3177 to MCTX->STATE_LOG. */
3178 if (to_idx == cur_str)
3180 /* The backreference did epsilon transit, we must re-check all the
3181 node in the current state. */
3182 re_node_set new_dests;
3183 reg_errcode_t err2, err3;
3184 next_node = dfa->edests[ent->node].elems[0];
3185 if (re_node_set_contains (cur_nodes, next_node))
3187 err = re_node_set_init_1 (&new_dests, next_node);
3188 err2 = check_arrival_expand_ecl (dfa, &new_dests, subexp_num, type);
3189 err3 = re_node_set_merge (cur_nodes, &new_dests);
3190 re_node_set_free (&new_dests);
3191 if (BE (err != REG_NOERROR || err2 != REG_NOERROR
3192 || err3 != REG_NOERROR, 0))
3194 err = (err != REG_NOERROR ? err
3195 : (err2 != REG_NOERROR ? err2 : err3));
3198 /* TODO: It is still inefficient... */
3203 re_node_set union_set;
3204 next_node = dfa->nexts[ent->node];
3205 if (mctx->state_log[to_idx])
3208 if (re_node_set_contains (&mctx->state_log[to_idx]->nodes,
3211 err = re_node_set_init_copy (&union_set,
3212 &mctx->state_log[to_idx]->nodes);
3213 ret = re_node_set_insert (&union_set, next_node);
3214 if (BE (err != REG_NOERROR || ret < 0, 0))
3216 re_node_set_free (&union_set);
3217 err = err != REG_NOERROR ? err : REG_ESPACE;
3223 err = re_node_set_init_1 (&union_set, next_node);
3224 if (BE (err != REG_NOERROR, 0))
3227 mctx->state_log[to_idx] = re_acquire_state (&err, dfa, &union_set);
3228 re_node_set_free (&union_set);
3229 if (BE (mctx->state_log[to_idx] == NULL
3230 && err != REG_NOERROR, 0))
3234 while (ent++->more);
3238 /* Build transition table for the state.
3239 Return 1 if succeeded, otherwise return NULL. */
3243 build_trtable (re_dfa_t *dfa, re_dfastate_t *state)
3246 int i, j, ch, need_word_trtable = 0;
3247 unsigned int elem, mask;
3248 int dests_node_malloced = 0, dest_states_malloced = 0;
3249 int ndests; /* Number of the destination states from `state'. */
3250 re_dfastate_t **trtable;
3251 re_dfastate_t **dest_states = NULL, **dest_states_word, **dest_states_nl;
3252 re_node_set follows, *dests_node;
3256 /* We build DFA states which corresponds to the destination nodes
3257 from `state'. `dests_node[i]' represents the nodes which i-th
3258 destination state contains, and `dests_ch[i]' represents the
3259 characters which i-th destination state accepts. */
3260 if (__libc_use_alloca ((sizeof (re_node_set) + sizeof (bitset)) * SBC_MAX))
3261 dests_node = (re_node_set *)
3262 alloca ((sizeof (re_node_set) + sizeof (bitset)) * SBC_MAX);
3265 dests_node = (re_node_set *)
3266 malloc ((sizeof (re_node_set) + sizeof (bitset)) * SBC_MAX);
3267 if (BE (dests_node == NULL, 0))
3269 dests_node_malloced = 1;
3271 dests_ch = (bitset *) (dests_node + SBC_MAX);
3273 /* Initialize transiton table. */
3274 state->word_trtable = state->trtable = NULL;
3276 /* At first, group all nodes belonging to `state' into several
3278 ndests = group_nodes_into_DFAstates (dfa, state, dests_node, dests_ch);
3279 if (BE (ndests <= 0, 0))
3281 if (dests_node_malloced)
3283 /* Return 0 in case of an error, 1 otherwise. */
3286 state->trtable = re_calloc (re_dfastate_t *, SBC_MAX);
3292 err = re_node_set_alloc (&follows, ndests + 1);
3293 if (BE (err != REG_NOERROR, 0))
3296 if (__libc_use_alloca ((sizeof (re_node_set) + sizeof (bitset)) * SBC_MAX
3297 + ndests * 3 * sizeof (re_dfastate_t *)))
3298 dest_states = (re_dfastate_t **)
3299 alloca (ndests * 3 * sizeof (re_dfastate_t *));
3302 dest_states = (re_dfastate_t **)
3303 malloc (ndests * 3 * sizeof (re_dfastate_t *));
3304 if (BE (dest_states == NULL, 0))
3307 if (dest_states_malloced)
3309 re_node_set_free (&follows);
3310 for (i = 0; i < ndests; ++i)
3311 re_node_set_free (dests_node + i);
3312 if (dests_node_malloced)
3316 dest_states_malloced = 1;
3318 dest_states_word = dest_states + ndests;
3319 dest_states_nl = dest_states_word + ndests;
3320 bitset_empty (acceptable);
3322 /* Then build the states for all destinations. */
3323 for (i = 0; i < ndests; ++i)
3326 re_node_set_empty (&follows);
3327 /* Merge the follows of this destination states. */
3328 for (j = 0; j < dests_node[i].nelem; ++j)
3330 next_node = dfa->nexts[dests_node[i].elems[j]];
3331 if (next_node != -1)
3333 err = re_node_set_merge (&follows, dfa->eclosures + next_node);
3334 if (BE (err != REG_NOERROR, 0))
3338 dest_states[i] = re_acquire_state_context (&err, dfa, &follows, 0);
3339 if (BE (dest_states[i] == NULL && err != REG_NOERROR, 0))
3341 /* If the new state has context constraint,
3342 build appropriate states for these contexts. */
3343 if (dest_states[i]->has_constraint)
3345 dest_states_word[i] = re_acquire_state_context (&err, dfa, &follows,
3347 if (BE (dest_states_word[i] == NULL && err != REG_NOERROR, 0))
3350 if (dest_states[i] != dest_states_word[i] && dfa->mb_cur_max > 1)
3351 need_word_trtable = 1;
3353 dest_states_nl[i] = re_acquire_state_context (&err, dfa, &follows,
3355 if (BE (dest_states_nl[i] == NULL && err != REG_NOERROR, 0))
3360 dest_states_word[i] = dest_states[i];
3361 dest_states_nl[i] = dest_states[i];
3363 bitset_merge (acceptable, dests_ch[i]);
3366 if (!BE (need_word_trtable, 0))
3368 /* We don't care about whether the following character is a word
3369 character, or we are in a single-byte character set so we can
3370 discern by looking at the character code: allocate a
3371 256-entry transition table. */
3372 trtable = state->trtable = re_calloc (re_dfastate_t *, SBC_MAX);
3373 if (BE (trtable == NULL, 0))
3376 /* For all characters ch...: */
3377 for (i = 0; i < BITSET_UINTS; ++i)
3378 for (ch = i * UINT_BITS, elem = acceptable[i], mask = 1;
3380 mask <<= 1, elem >>= 1, ++ch)
3381 if (BE (elem & 1, 0))
3383 /* There must be exactly one destination which accepts
3384 character ch. See group_nodes_into_DFAstates. */
3385 for (j = 0; (dests_ch[j][i] & mask) == 0; ++j)
3388 /* j-th destination accepts the word character ch. */
3389 if (dfa->word_char[i] & mask)
3390 trtable[ch] = dest_states_word[j];
3392 trtable[ch] = dest_states[j];
3397 /* We care about whether the following character is a word
3398 character, and we are in a multi-byte character set: discern
3399 by looking at the character code: build two 256-entry
3400 transition tables, one starting at trtable[0] and one
3401 starting at trtable[SBC_MAX]. */
3402 trtable = state->word_trtable = re_calloc (re_dfastate_t *, 2 * SBC_MAX);
3403 if (BE (trtable == NULL, 0))
3406 /* For all characters ch...: */
3407 for (i = 0; i < BITSET_UINTS; ++i)
3408 for (ch = i * UINT_BITS, elem = acceptable[i], mask = 1;
3410 mask <<= 1, elem >>= 1, ++ch)
3411 if (BE (elem & 1, 0))
3413 /* There must be exactly one destination which accepts
3414 character ch. See group_nodes_into_DFAstates. */
3415 for (j = 0; (dests_ch[j][i] & mask) == 0; ++j)
3418 /* j-th destination accepts the word character ch. */
3419 trtable[ch] = dest_states[j];
3420 trtable[ch + SBC_MAX] = dest_states_word[j];
3425 if (bitset_contain (acceptable, NEWLINE_CHAR))
3427 /* The current state accepts newline character. */
3428 for (j = 0; j < ndests; ++j)
3429 if (bitset_contain (dests_ch[j], NEWLINE_CHAR))
3431 /* k-th destination accepts newline character. */
3432 trtable[NEWLINE_CHAR] = dest_states_nl[j];
3433 if (need_word_trtable)
3434 trtable[NEWLINE_CHAR + SBC_MAX] = dest_states_nl[j];
3435 /* There must be only one destination which accepts
3436 newline. See group_nodes_into_DFAstates. */
3441 if (dest_states_malloced)
3444 re_node_set_free (&follows);
3445 for (i = 0; i < ndests; ++i)
3446 re_node_set_free (dests_node + i);
3448 if (dests_node_malloced)
3454 /* Group all nodes belonging to STATE into several destinations.
3455 Then for all destinations, set the nodes belonging to the destination
3456 to DESTS_NODE[i] and set the characters accepted by the destination
3457 to DEST_CH[i]. This function return the number of destinations. */
3461 group_nodes_into_DFAstates (re_dfa_t *dfa, const re_dfastate_t *state,
3462 re_node_set *dests_node, bitset *dests_ch)
3467 int ndests; /* Number of the destinations from `state'. */
3468 bitset accepts; /* Characters a node can accept. */
3469 const re_node_set *cur_nodes = &state->nodes;
3470 bitset_empty (accepts);
3473 /* For all the nodes belonging to `state', */
3474 for (i = 0; i < cur_nodes->nelem; ++i)
3476 re_token_t *node = &dfa->nodes[cur_nodes->elems[i]];
3477 re_token_type_t type = node->type;
3478 unsigned int constraint = node->constraint;
3480 /* Enumerate all single byte character this node can accept. */
3481 if (type == CHARACTER)
3482 bitset_set (accepts, node->opr.c);
3483 else if (type == SIMPLE_BRACKET)
3485 bitset_merge (accepts, node->opr.sbcset);
3487 else if (type == OP_PERIOD)
3489 #ifdef RE_ENABLE_I18N
3490 if (dfa->mb_cur_max > 1)
3491 bitset_merge (accepts, dfa->sb_char);
3494 bitset_set_all (accepts);
3495 if (!(dfa->syntax & REG_DOT_NEWLINE))
3496 bitset_clear (accepts, '\n');
3497 if (dfa->syntax & REG_DOT_NOT_NULL)
3498 bitset_clear (accepts, '\0');
3500 #ifdef RE_ENABLE_I18N
3501 else if (type == OP_UTF8_PERIOD)
3503 memset (accepts, 255, sizeof (unsigned int) * BITSET_UINTS / 2);
3504 if (!(dfa->syntax & REG_DOT_NEWLINE))
3505 bitset_clear (accepts, '\n');
3506 if (dfa->syntax & REG_DOT_NOT_NULL)
3507 bitset_clear (accepts, '\0');
3513 /* Check the `accepts' and sift the characters which are not
3514 match it the context. */
3517 if (constraint & NEXT_NEWLINE_CONSTRAINT)
3519 int accepts_newline = bitset_contain (accepts, NEWLINE_CHAR);
3520 bitset_empty (accepts);
3521 if (accepts_newline)
3522 bitset_set (accepts, NEWLINE_CHAR);
3526 if (constraint & NEXT_ENDBUF_CONSTRAINT)
3528 bitset_empty (accepts);
3532 if (constraint & NEXT_WORD_CONSTRAINT)
3534 unsigned int any_set = 0;
3535 if (type == CHARACTER && !node->word_char)
3537 bitset_empty (accepts);
3540 #ifdef RE_ENABLE_I18N
3541 if (dfa->mb_cur_max > 1)
3542 for (j = 0; j < BITSET_UINTS; ++j)
3543 any_set |= (accepts[j] &= (dfa->word_char[j] | ~dfa->sb_char[j]));
3546 for (j = 0; j < BITSET_UINTS; ++j)
3547 any_set |= (accepts[j] &= dfa->word_char[j]);
3551 if (constraint & NEXT_NOTWORD_CONSTRAINT)
3553 unsigned int any_set = 0;
3554 if (type == CHARACTER && node->word_char)
3556 bitset_empty (accepts);
3559 #ifdef RE_ENABLE_I18N
3560 if (dfa->mb_cur_max > 1)
3561 for (j = 0; j < BITSET_UINTS; ++j)
3562 any_set |= (accepts[j] &= ~(dfa->word_char[j] & dfa->sb_char[j]));
3565 for (j = 0; j < BITSET_UINTS; ++j)
3566 any_set |= (accepts[j] &= ~dfa->word_char[j]);
3572 /* Then divide `accepts' into DFA states, or create a new
3573 state. Above, we make sure that accepts is not empty. */
3574 for (j = 0; j < ndests; ++j)
3576 bitset intersec; /* Intersection sets, see below. */
3578 /* Flags, see below. */
3579 int has_intersec, not_subset, not_consumed;
3581 /* Optimization, skip if this state doesn't accept the character. */
3582 if (type == CHARACTER && !bitset_contain (dests_ch[j], node->opr.c))
3585 /* Enumerate the intersection set of this state and `accepts'. */
3587 for (k = 0; k < BITSET_UINTS; ++k)
3588 has_intersec |= intersec[k] = accepts[k] & dests_ch[j][k];
3589 /* And skip if the intersection set is empty. */
3593 /* Then check if this state is a subset of `accepts'. */
3594 not_subset = not_consumed = 0;
3595 for (k = 0; k < BITSET_UINTS; ++k)
3597 not_subset |= remains[k] = ~accepts[k] & dests_ch[j][k];
3598 not_consumed |= accepts[k] = accepts[k] & ~dests_ch[j][k];
3601 /* If this state isn't a subset of `accepts', create a
3602 new group state, which has the `remains'. */
3605 bitset_copy (dests_ch[ndests], remains);
3606 bitset_copy (dests_ch[j], intersec);
3607 err = re_node_set_init_copy (dests_node + ndests, &dests_node[j]);
3608 if (BE (err != REG_NOERROR, 0))
3613 /* Put the position in the current group. */
3614 result = re_node_set_insert (&dests_node[j], cur_nodes->elems[i]);
3615 if (BE (result < 0, 0))
3618 /* If all characters are consumed, go to next node. */
3622 /* Some characters remain, create a new group. */
3625 bitset_copy (dests_ch[ndests], accepts);
3626 err = re_node_set_init_1 (dests_node + ndests, cur_nodes->elems[i]);
3627 if (BE (err != REG_NOERROR, 0))
3630 bitset_empty (accepts);
3635 for (j = 0; j < ndests; ++j)
3636 re_node_set_free (dests_node + j);
3640 #ifdef RE_ENABLE_I18N
3641 /* Check how many bytes the node `dfa->nodes[node_idx]' accepts.
3642 Return the number of the bytes the node accepts.
3643 STR_IDX is the current index of the input string.
3645 This function handles the nodes which can accept one character, or
3646 one collating element like '.', '[a-z]', opposite to the other nodes
3647 can only accept one byte. */
3651 check_node_accept_bytes (re_dfa_t *dfa, int node_idx,
3652 const re_string_t *input, int str_idx)
3654 const re_token_t *node = dfa->nodes + node_idx;
3655 int char_len, elem_len;
3658 if (BE (node->type == OP_UTF8_PERIOD, 0))
3660 unsigned char c = re_string_byte_at (input, str_idx), d;
3661 if (BE (c < 0xc2, 1))
3664 if (str_idx + 2 > input->len)
3667 d = re_string_byte_at (input, str_idx + 1);
3669 return (d < 0x80 || d > 0xbf) ? 0 : 2;
3673 if (c == 0xe0 && d < 0xa0)
3679 if (c == 0xf0 && d < 0x90)
3685 if (c == 0xf8 && d < 0x88)
3691 if (c == 0xfc && d < 0x84)
3697 if (str_idx + char_len > input->len)
3700 for (i = 1; i < char_len; ++i)
3702 d = re_string_byte_at (input, str_idx + i);
3703 if (d < 0x80 || d > 0xbf)
3709 char_len = re_string_char_size_at (input, str_idx);
3710 if (node->type == OP_PERIOD)
3714 /* FIXME: I don't think this if is needed, as both '\n'
3715 and '\0' are char_len == 1. */
3716 /* '.' accepts any one character except the following two cases. */
3717 if ((!(dfa->syntax & REG_DOT_NEWLINE) &&
3718 re_string_byte_at (input, str_idx) == '\n') ||
3719 ((dfa->syntax & REG_DOT_NOT_NULL) &&
3720 re_string_byte_at (input, str_idx) == '\0'))
3725 elem_len = re_string_elem_size_at (input, str_idx);
3726 if ((elem_len <= 1 && char_len <= 1) || char_len == 0)
3729 if (node->type == COMPLEX_BRACKET)
3731 const re_charset_t *cset = node->opr.mbcset;
3733 const unsigned char *pin
3734 = ((const unsigned char *) re_string_get_buffer (input) + str_idx);
3739 wchar_t wc = ((cset->nranges || cset->nchar_classes || cset->nmbchars)
3740 ? re_string_wchar_at (input, str_idx) : 0);
3742 /* match with multibyte character? */
3743 for (i = 0; i < cset->nmbchars; ++i)
3744 if (wc == cset->mbchars[i])
3746 match_len = char_len;
3747 goto check_node_accept_bytes_match;
3749 /* match with character_class? */
3750 for (i = 0; i < cset->nchar_classes; ++i)
3752 wctype_t wt = cset->char_classes[i];
3753 if (__iswctype (wc, wt))
3755 match_len = char_len;
3756 goto check_node_accept_bytes_match;
3761 nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
3764 unsigned int in_collseq = 0;
3765 const int32_t *table, *indirect;
3766 const unsigned char *weights, *extra;
3767 const char *collseqwc;
3769 /* This #include defines a local function! */
3770 # include <locale/weight.h>
3772 /* match with collating_symbol? */
3773 if (cset->ncoll_syms)
3774 extra = (const unsigned char *)
3775 _NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB);
3776 for (i = 0; i < cset->ncoll_syms; ++i)
3778 const unsigned char *coll_sym = extra + cset->coll_syms[i];
3779 /* Compare the length of input collating element and
3780 the length of current collating element. */
3781 if (*coll_sym != elem_len)
3783 /* Compare each bytes. */
3784 for (j = 0; j < *coll_sym; j++)
3785 if (pin[j] != coll_sym[1 + j])
3789 /* Match if every bytes is equal. */
3791 goto check_node_accept_bytes_match;
3797 if (elem_len <= char_len)
3799 collseqwc = _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQWC);
3800 in_collseq = __collseq_table_lookup (collseqwc, wc);
3803 in_collseq = find_collation_sequence_value (pin, elem_len);
3805 /* match with range expression? */
3806 for (i = 0; i < cset->nranges; ++i)
3807 if (cset->range_starts[i] <= in_collseq
3808 && in_collseq <= cset->range_ends[i])
3810 match_len = elem_len;
3811 goto check_node_accept_bytes_match;
3814 /* match with equivalence_class? */
3815 if (cset->nequiv_classes)
3817 const unsigned char *cp = pin;
3818 table = (const int32_t *)
3819 _NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB);
3820 weights = (const unsigned char *)
3821 _NL_CURRENT (LC_COLLATE, _NL_COLLATE_WEIGHTMB);
3822 extra = (const unsigned char *)
3823 _NL_CURRENT (LC_COLLATE, _NL_COLLATE_EXTRAMB);
3824 indirect = (const int32_t *)
3825 _NL_CURRENT (LC_COLLATE, _NL_COLLATE_INDIRECTMB);
3826 idx = findidx (&cp);
3828 for (i = 0; i < cset->nequiv_classes; ++i)
3830 int32_t equiv_class_idx = cset->equiv_classes[i];
3831 size_t weight_len = weights[idx];
3832 if (weight_len == weights[equiv_class_idx])
3835 while (cnt <= weight_len
3836 && (weights[equiv_class_idx + 1 + cnt]
3837 == weights[idx + 1 + cnt]))
3839 if (cnt > weight_len)
3841 match_len = elem_len;
3842 goto check_node_accept_bytes_match;
3851 /* match with range expression? */
3853 wchar_t cmp_buf[] = {L'\0', L'\0', wc, L'\0', L'\0', L'\0'};
3855 wchar_t cmp_buf[] = {L'\0', L'\0', L'\0', L'\0', L'\0', L'\0'};
3858 for (i = 0; i < cset->nranges; ++i)
3860 cmp_buf[0] = cset->range_starts[i];
3861 cmp_buf[4] = cset->range_ends[i];
3862 if (wcscoll (cmp_buf, cmp_buf + 2) <= 0
3863 && wcscoll (cmp_buf + 2, cmp_buf + 4) <= 0)
3865 match_len = char_len;
3866 goto check_node_accept_bytes_match;
3870 check_node_accept_bytes_match:
3871 if (!cset->non_match)
3878 return (elem_len > char_len) ? elem_len : char_len;
3886 find_collation_sequence_value (mbs, mbs_len)
3887 const unsigned char *mbs;
3890 uint32_t nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
3895 /* No valid character. Match it as a single byte character. */
3896 const unsigned char *collseq = (const unsigned char *)
3897 _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQMB);
3898 return collseq[mbs[0]];
3905 const unsigned char *extra = (const unsigned char *)
3906 _NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB);
3907 int32_t extrasize = (const unsigned char *)
3908 _NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB + 1) - extra;
3910 for (idx = 0; idx < extrasize;)
3912 int mbs_cnt, found = 0;
3913 int32_t elem_mbs_len;
3914 /* Skip the name of collating element name. */
3915 idx = idx + extra[idx] + 1;
3916 elem_mbs_len = extra[idx++];
3917 if (mbs_len == elem_mbs_len)
3919 for (mbs_cnt = 0; mbs_cnt < elem_mbs_len; ++mbs_cnt)
3920 if (extra[idx + mbs_cnt] != mbs[mbs_cnt])
3922 if (mbs_cnt == elem_mbs_len)
3923 /* Found the entry. */
3926 /* Skip the byte sequence of the collating element. */
3927 idx += elem_mbs_len;
3928 /* Adjust for the alignment. */
3929 idx = (idx + 3) & ~3;
3930 /* Skip the collation sequence value. */
3931 idx += sizeof (uint32_t);
3932 /* Skip the wide char sequence of the collating element. */
3933 idx = idx + sizeof (uint32_t) * (extra[idx] + 1);
3934 /* If we found the entry, return the sequence value. */
3936 return *(uint32_t *) (extra + idx);
3937 /* Skip the collation sequence value. */
3938 idx += sizeof (uint32_t);
3944 #endif /* RE_ENABLE_I18N */
3946 /* Check whether the node accepts the byte which is IDX-th
3947 byte of the INPUT. */
3951 check_node_accept (const re_match_context_t *mctx, const re_token_t *node,
3955 ch = re_string_byte_at (&mctx->input, idx);
3959 if (node->opr.c != ch)
3963 case SIMPLE_BRACKET:
3964 if (!bitset_contain (node->opr.sbcset, ch))
3968 #ifdef RE_ENABLE_I18N
3969 case OP_UTF8_PERIOD:
3975 if ((ch == '\n' && !(mctx->dfa->syntax & REG_DOT_NEWLINE))
3976 || (ch == '\0' && (mctx->dfa->syntax & REG_DOT_NOT_NULL)))
3984 if (node->constraint)
3986 /* The node has constraints. Check whether the current context
3987 satisfies the constraints. */
3988 unsigned int context = re_string_context_at (&mctx->input, idx,
3990 if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context))
3997 /* Extend the buffers, if the buffers have run out. */
3999 static reg_errcode_t
4001 extend_buffers (re_match_context_t *mctx)
4004 re_string_t *pstr = &mctx->input;
4006 /* Double the lengthes of the buffers. */
4007 ret = re_string_realloc_buffers (pstr, pstr->bufs_len * 2);
4008 if (BE (ret != REG_NOERROR, 0))
4011 if (mctx->state_log != NULL)
4013 /* And double the length of state_log. */
4014 /* XXX We have no indication of the size of this buffer. If this
4015 allocation fail we have no indication that the state_log array
4016 does not have the right size. */
4017 re_dfastate_t **new_array = re_realloc (mctx->state_log, re_dfastate_t *,
4018 pstr->bufs_len + 1);
4019 if (BE (new_array == NULL, 0))
4021 mctx->state_log = new_array;
4024 /* Then reconstruct the buffers. */
4027 #ifdef RE_ENABLE_I18N
4028 if (pstr->mb_cur_max > 1)
4030 ret = build_wcs_upper_buffer (pstr);
4031 if (BE (ret != REG_NOERROR, 0))
4035 #endif /* RE_ENABLE_I18N */
4036 build_upper_buffer (pstr);
4040 #ifdef RE_ENABLE_I18N
4041 if (pstr->mb_cur_max > 1)
4042 build_wcs_buffer (pstr);
4044 #endif /* RE_ENABLE_I18N */
4046 if (pstr->trans != NULL)
4047 re_string_translate_buffer (pstr);
4054 /* Functions for matching context. */
4056 /* Initialize MCTX. */
4058 static reg_errcode_t
4060 match_ctx_init (re_match_context_t *mctx, int eflags, int n)
4062 mctx->eflags = eflags;
4063 mctx->match_last = -1;
4066 mctx->bkref_ents = re_malloc (struct re_backref_cache_entry, n);
4067 mctx->sub_tops = re_malloc (re_sub_match_top_t *, n);
4068 if (BE (mctx->bkref_ents == NULL || mctx->sub_tops == NULL, 0))
4071 /* Already zero-ed by the caller.
4073 mctx->bkref_ents = NULL;
4074 mctx->nbkref_ents = 0;
4075 mctx->nsub_tops = 0; */
4076 mctx->abkref_ents = n;
4077 mctx->max_mb_elem_len = 1;
4078 mctx->asub_tops = n;
4082 /* Clean the entries which depend on the current input in MCTX.
4083 This function must be invoked when the matcher changes the start index
4084 of the input, or changes the input string. */
4088 match_ctx_clean (re_match_context_t *mctx)
4091 for (st_idx = 0; st_idx < mctx->nsub_tops; ++st_idx)
4094 re_sub_match_top_t *top = mctx->sub_tops[st_idx];
4095 for (sl_idx = 0; sl_idx < top->nlasts; ++sl_idx)
4097 re_sub_match_last_t *last = top->lasts[sl_idx];
4098 re_free (last->path.array);
4101 re_free (top->lasts);
4104 re_free (top->path->array);
4105 re_free (top->path);
4110 mctx->nsub_tops = 0;
4111 mctx->nbkref_ents = 0;
4114 /* Free all the memory associated with MCTX. */
4118 match_ctx_free (re_match_context_t *mctx)
4120 /* First, free all the memory associated with MCTX->SUB_TOPS. */
4121 match_ctx_clean (mctx);
4122 re_free (mctx->sub_tops);
4123 re_free (mctx->bkref_ents);
4126 /* Add a new backreference entry to MCTX.
4127 Note that we assume that caller never call this function with duplicate
4128 entry, and call with STR_IDX which isn't smaller than any existing entry.
4131 static reg_errcode_t
4133 match_ctx_add_entry (re_match_context_t *mctx, int node, int str_idx,
4136 if (mctx->nbkref_ents >= mctx->abkref_ents)
4138 struct re_backref_cache_entry* new_entry;
4139 new_entry = re_realloc (mctx->bkref_ents, struct re_backref_cache_entry,
4140 mctx->abkref_ents * 2);
4141 if (BE (new_entry == NULL, 0))
4143 re_free (mctx->bkref_ents);
4146 mctx->bkref_ents = new_entry;
4147 memset (mctx->bkref_ents + mctx->nbkref_ents, '\0',
4148 sizeof (struct re_backref_cache_entry) * mctx->abkref_ents);
4149 mctx->abkref_ents *= 2;
4151 if (mctx->nbkref_ents > 0
4152 && mctx->bkref_ents[mctx->nbkref_ents - 1].str_idx == str_idx)
4153 mctx->bkref_ents[mctx->nbkref_ents - 1].more = 1;
4155 mctx->bkref_ents[mctx->nbkref_ents].node = node;
4156 mctx->bkref_ents[mctx->nbkref_ents].str_idx = str_idx;
4157 mctx->bkref_ents[mctx->nbkref_ents].subexp_from = from;
4158 mctx->bkref_ents[mctx->nbkref_ents].subexp_to = to;
4160 /* This is a cache that saves negative results of check_dst_limits_calc_pos.
4161 If bit N is clear, means that this entry won't epsilon-transition to
4162 an OP_OPEN_SUBEXP or OP_CLOSE_SUBEXP for the N+1-th subexpression. If
4163 it is set, check_dst_limits_calc_pos_1 will recurse and try to find one
4166 A backreference does not epsilon-transition unless it is empty, so set
4167 to all zeros if FROM != TO. */
4168 mctx->bkref_ents[mctx->nbkref_ents].eps_reachable_subexps_map
4169 = (from == to ? ~0 : 0);
4171 mctx->bkref_ents[mctx->nbkref_ents++].more = 0;
4172 if (mctx->max_mb_elem_len < to - from)
4173 mctx->max_mb_elem_len = to - from;
4177 /* Search for the first entry which has the same str_idx, or -1 if none is
4178 found. Note that MCTX->BKREF_ENTS is already sorted by MCTX->STR_IDX. */
4182 search_cur_bkref_entry (re_match_context_t *mctx, int str_idx)
4184 int left, right, mid, last;
4185 last = right = mctx->nbkref_ents;
4186 for (left = 0; left < right;)
4188 mid = (left + right) / 2;
4189 if (mctx->bkref_ents[mid].str_idx < str_idx)
4194 if (left < last && mctx->bkref_ents[left].str_idx == str_idx)
4200 /* Register the node NODE, whose type is OP_OPEN_SUBEXP, and which matches
4203 static reg_errcode_t
4205 match_ctx_add_subtop (re_match_context_t *mctx, int node, int str_idx)
4208 assert (mctx->sub_tops != NULL);
4209 assert (mctx->asub_tops > 0);
4211 if (BE (mctx->nsub_tops == mctx->asub_tops, 0))
4213 int new_asub_tops = mctx->asub_tops * 2;
4214 re_sub_match_top_t **new_array = re_realloc (mctx->sub_tops,
4215 re_sub_match_top_t *,
4217 if (BE (new_array == NULL, 0))
4219 mctx->sub_tops = new_array;
4220 mctx->asub_tops = new_asub_tops;
4222 mctx->sub_tops[mctx->nsub_tops] = re_calloc (re_sub_match_top_t, 1);
4223 if (BE (mctx->sub_tops[mctx->nsub_tops] == NULL, 0))
4225 mctx->sub_tops[mctx->nsub_tops]->node = node;
4226 mctx->sub_tops[mctx->nsub_tops++]->str_idx = str_idx;
4230 /* Register the node NODE, whose type is OP_CLOSE_SUBEXP, and which matches
4231 at STR_IDX, whose corresponding OP_OPEN_SUBEXP is SUB_TOP. */
4233 static re_sub_match_last_t *
4235 match_ctx_add_sublast (re_sub_match_top_t *subtop, int node, int str_idx)
4237 re_sub_match_last_t *new_entry;
4238 if (BE (subtop->nlasts == subtop->alasts, 0))
4240 int new_alasts = 2 * subtop->alasts + 1;
4241 re_sub_match_last_t **new_array = re_realloc (subtop->lasts,
4242 re_sub_match_last_t *,
4244 if (BE (new_array == NULL, 0))
4246 subtop->lasts = new_array;
4247 subtop->alasts = new_alasts;
4249 new_entry = re_calloc (re_sub_match_last_t, 1);
4250 if (BE (new_entry != NULL, 1))
4252 subtop->lasts[subtop->nlasts] = new_entry;
4253 new_entry->node = node;
4254 new_entry->str_idx = str_idx;
4262 sift_ctx_init (re_sift_context_t *sctx,
4263 re_dfastate_t **sifted_sts,
4264 re_dfastate_t **limited_sts,
4265 int last_node, int last_str_idx)
4267 sctx->sifted_states = sifted_sts;
4268 sctx->limited_states = limited_sts;
4269 sctx->last_node = last_node;
4270 sctx->last_str_idx = last_str_idx;
4271 re_node_set_init_empty (&sctx->limits);