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eb4a14ed LC |
1 | /* Extended regular expression matching and search library. |
2 | Copyright (C) 2002-2012 Free Software Foundation, Inc. | |
3 | This file is part of the GNU C Library. | |
4 | Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>. | |
5 | ||
6 | This program is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU Lesser General Public License as published by | |
8 | the Free Software Foundation; either version 2, or (at your option) | |
9 | any later version. | |
10 | ||
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 Lesser General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU Lesser 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. */ | |
19 | ||
20 | static reg_errcode_t match_ctx_init (re_match_context_t *cache, int eflags, | |
21 | Idx 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, Idx node, | |
25 | Idx str_idx, Idx from, Idx to) | |
26 | internal_function; | |
27 | static Idx search_cur_bkref_entry (const re_match_context_t *mctx, Idx str_idx) | |
28 | internal_function; | |
29 | static reg_errcode_t match_ctx_add_subtop (re_match_context_t *mctx, Idx node, | |
30 | Idx str_idx) internal_function; | |
31 | static re_sub_match_last_t * match_ctx_add_sublast (re_sub_match_top_t *subtop, | |
32 | Idx node, Idx str_idx) | |
33 | internal_function; | |
34 | static void sift_ctx_init (re_sift_context_t *sctx, re_dfastate_t **sifted_sts, | |
35 | re_dfastate_t **limited_sts, Idx last_node, | |
36 | Idx last_str_idx) | |
37 | internal_function; | |
38 | static reg_errcode_t re_search_internal (const regex_t *preg, | |
39 | const char *string, Idx length, | |
40 | Idx start, Idx last_start, Idx stop, | |
41 | size_t nmatch, regmatch_t pmatch[], | |
42 | int eflags) internal_function; | |
43 | static regoff_t re_search_2_stub (struct re_pattern_buffer *bufp, | |
44 | const char *string1, Idx length1, | |
45 | const char *string2, Idx length2, | |
46 | Idx start, regoff_t range, | |
47 | struct re_registers *regs, | |
48 | Idx stop, bool ret_len) internal_function; | |
49 | static regoff_t re_search_stub (struct re_pattern_buffer *bufp, | |
50 | const char *string, Idx length, Idx start, | |
51 | regoff_t range, Idx stop, | |
52 | struct re_registers *regs, | |
53 | bool ret_len) internal_function; | |
54 | static unsigned int re_copy_regs (struct re_registers *regs, regmatch_t *pmatch, | |
55 | Idx nregs, int regs_allocated) | |
56 | internal_function; | |
57 | static reg_errcode_t prune_impossible_nodes (re_match_context_t *mctx) | |
58 | internal_function; | |
59 | static Idx check_matching (re_match_context_t *mctx, bool fl_longest_match, | |
60 | Idx *p_match_first) internal_function; | |
61 | static Idx check_halt_state_context (const re_match_context_t *mctx, | |
62 | const re_dfastate_t *state, Idx idx) | |
63 | internal_function; | |
64 | static void update_regs (const re_dfa_t *dfa, regmatch_t *pmatch, | |
65 | regmatch_t *prev_idx_match, Idx cur_node, | |
66 | Idx cur_idx, Idx nmatch) internal_function; | |
67 | static reg_errcode_t push_fail_stack (struct re_fail_stack_t *fs, | |
68 | Idx str_idx, Idx dest_node, Idx nregs, | |
69 | regmatch_t *regs, | |
70 | re_node_set *eps_via_nodes) | |
71 | internal_function; | |
72 | static reg_errcode_t set_regs (const regex_t *preg, | |
73 | const re_match_context_t *mctx, | |
74 | size_t nmatch, regmatch_t *pmatch, | |
75 | bool fl_backtrack) internal_function; | |
76 | static reg_errcode_t free_fail_stack_return (struct re_fail_stack_t *fs) | |
77 | internal_function; | |
78 | ||
79 | #ifdef RE_ENABLE_I18N | |
80 | static int sift_states_iter_mb (const re_match_context_t *mctx, | |
81 | re_sift_context_t *sctx, | |
82 | Idx node_idx, Idx str_idx, Idx max_str_idx) | |
83 | internal_function; | |
84 | #endif /* RE_ENABLE_I18N */ | |
85 | static reg_errcode_t sift_states_backward (const re_match_context_t *mctx, | |
86 | re_sift_context_t *sctx) | |
87 | internal_function; | |
88 | static reg_errcode_t build_sifted_states (const re_match_context_t *mctx, | |
89 | re_sift_context_t *sctx, Idx str_idx, | |
90 | re_node_set *cur_dest) | |
91 | internal_function; | |
92 | static reg_errcode_t update_cur_sifted_state (const re_match_context_t *mctx, | |
93 | re_sift_context_t *sctx, | |
94 | Idx str_idx, | |
95 | re_node_set *dest_nodes) | |
96 | internal_function; | |
97 | static reg_errcode_t add_epsilon_src_nodes (const re_dfa_t *dfa, | |
98 | re_node_set *dest_nodes, | |
99 | const re_node_set *candidates) | |
100 | internal_function; | |
101 | static bool check_dst_limits (const re_match_context_t *mctx, | |
102 | const re_node_set *limits, | |
103 | Idx dst_node, Idx dst_idx, Idx src_node, | |
104 | Idx src_idx) internal_function; | |
105 | static int check_dst_limits_calc_pos_1 (const re_match_context_t *mctx, | |
106 | int boundaries, Idx subexp_idx, | |
107 | Idx from_node, Idx bkref_idx) | |
108 | internal_function; | |
109 | static int check_dst_limits_calc_pos (const re_match_context_t *mctx, | |
110 | Idx limit, Idx subexp_idx, | |
111 | Idx node, Idx str_idx, | |
112 | Idx bkref_idx) internal_function; | |
113 | static reg_errcode_t check_subexp_limits (const re_dfa_t *dfa, | |
114 | re_node_set *dest_nodes, | |
115 | const re_node_set *candidates, | |
116 | re_node_set *limits, | |
117 | struct re_backref_cache_entry *bkref_ents, | |
118 | Idx str_idx) internal_function; | |
119 | static reg_errcode_t sift_states_bkref (const re_match_context_t *mctx, | |
120 | re_sift_context_t *sctx, | |
121 | Idx str_idx, const re_node_set *candidates) | |
122 | internal_function; | |
123 | static reg_errcode_t merge_state_array (const re_dfa_t *dfa, | |
124 | re_dfastate_t **dst, | |
125 | re_dfastate_t **src, Idx num) | |
126 | internal_function; | |
127 | static re_dfastate_t *find_recover_state (reg_errcode_t *err, | |
128 | re_match_context_t *mctx) internal_function; | |
129 | static re_dfastate_t *transit_state (reg_errcode_t *err, | |
130 | re_match_context_t *mctx, | |
131 | re_dfastate_t *state) internal_function; | |
132 | static re_dfastate_t *merge_state_with_log (reg_errcode_t *err, | |
133 | re_match_context_t *mctx, | |
134 | re_dfastate_t *next_state) | |
135 | internal_function; | |
136 | static reg_errcode_t check_subexp_matching_top (re_match_context_t *mctx, | |
137 | re_node_set *cur_nodes, | |
138 | Idx str_idx) internal_function; | |
139 | #if 0 | |
140 | static re_dfastate_t *transit_state_sb (reg_errcode_t *err, | |
141 | re_match_context_t *mctx, | |
142 | re_dfastate_t *pstate) | |
143 | internal_function; | |
144 | #endif | |
145 | #ifdef RE_ENABLE_I18N | |
146 | static reg_errcode_t transit_state_mb (re_match_context_t *mctx, | |
147 | re_dfastate_t *pstate) | |
148 | internal_function; | |
149 | #endif /* RE_ENABLE_I18N */ | |
150 | static reg_errcode_t transit_state_bkref (re_match_context_t *mctx, | |
151 | const re_node_set *nodes) | |
152 | internal_function; | |
153 | static reg_errcode_t get_subexp (re_match_context_t *mctx, | |
154 | Idx bkref_node, Idx bkref_str_idx) | |
155 | internal_function; | |
156 | static reg_errcode_t get_subexp_sub (re_match_context_t *mctx, | |
157 | const re_sub_match_top_t *sub_top, | |
158 | re_sub_match_last_t *sub_last, | |
159 | Idx bkref_node, Idx bkref_str) | |
160 | internal_function; | |
161 | static Idx find_subexp_node (const re_dfa_t *dfa, const re_node_set *nodes, | |
162 | Idx subexp_idx, int type) internal_function; | |
163 | static reg_errcode_t check_arrival (re_match_context_t *mctx, | |
164 | state_array_t *path, Idx top_node, | |
165 | Idx top_str, Idx last_node, Idx last_str, | |
166 | int type) internal_function; | |
167 | static reg_errcode_t check_arrival_add_next_nodes (re_match_context_t *mctx, | |
168 | Idx str_idx, | |
169 | re_node_set *cur_nodes, | |
170 | re_node_set *next_nodes) | |
171 | internal_function; | |
172 | static reg_errcode_t check_arrival_expand_ecl (const re_dfa_t *dfa, | |
173 | re_node_set *cur_nodes, | |
174 | Idx ex_subexp, int type) | |
175 | internal_function; | |
176 | static reg_errcode_t check_arrival_expand_ecl_sub (const re_dfa_t *dfa, | |
177 | re_node_set *dst_nodes, | |
178 | Idx target, Idx ex_subexp, | |
179 | int type) internal_function; | |
180 | static reg_errcode_t expand_bkref_cache (re_match_context_t *mctx, | |
181 | re_node_set *cur_nodes, Idx cur_str, | |
182 | Idx subexp_num, int type) | |
183 | internal_function; | |
184 | static bool build_trtable (const re_dfa_t *dfa, | |
185 | re_dfastate_t *state) internal_function; | |
186 | #ifdef RE_ENABLE_I18N | |
187 | static int check_node_accept_bytes (const re_dfa_t *dfa, Idx node_idx, | |
188 | const re_string_t *input, Idx idx) | |
189 | internal_function; | |
190 | # ifdef _LIBC | |
191 | static unsigned int find_collation_sequence_value (const unsigned char *mbs, | |
192 | size_t name_len) | |
193 | internal_function; | |
194 | # endif /* _LIBC */ | |
195 | #endif /* RE_ENABLE_I18N */ | |
196 | static Idx group_nodes_into_DFAstates (const re_dfa_t *dfa, | |
197 | const re_dfastate_t *state, | |
198 | re_node_set *states_node, | |
199 | bitset_t *states_ch) internal_function; | |
200 | static bool check_node_accept (const re_match_context_t *mctx, | |
201 | const re_token_t *node, Idx idx) | |
202 | internal_function; | |
203 | static reg_errcode_t extend_buffers (re_match_context_t *mctx) | |
204 | internal_function; | |
205 | \f | |
206 | /* Entry point for POSIX code. */ | |
207 | ||
208 | /* regexec searches for a given pattern, specified by PREG, in the | |
209 | string STRING. | |
210 | ||
211 | If NMATCH is zero or REG_NOSUB was set in the cflags argument to | |
212 | 'regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at | |
213 | least NMATCH elements, and we set them to the offsets of the | |
214 | corresponding matched substrings. | |
215 | ||
216 | EFLAGS specifies "execution flags" which affect matching: if | |
217 | REG_NOTBOL is set, then ^ does not match at the beginning of the | |
218 | string; if REG_NOTEOL is set, then $ does not match at the end. | |
219 | ||
220 | We return 0 if we find a match and REG_NOMATCH if not. */ | |
221 | ||
222 | int | |
223 | regexec (preg, string, nmatch, pmatch, eflags) | |
224 | const regex_t *_Restrict_ preg; | |
225 | const char *_Restrict_ string; | |
226 | size_t nmatch; | |
227 | regmatch_t pmatch[_Restrict_arr_]; | |
228 | int eflags; | |
229 | { | |
230 | reg_errcode_t err; | |
231 | Idx start, length; | |
232 | #ifdef _LIBC | |
233 | re_dfa_t *dfa = (re_dfa_t *) preg->buffer; | |
234 | #endif | |
235 | ||
236 | if (eflags & ~(REG_NOTBOL | REG_NOTEOL | REG_STARTEND)) | |
237 | return REG_BADPAT; | |
238 | ||
239 | if (eflags & REG_STARTEND) | |
240 | { | |
241 | start = pmatch[0].rm_so; | |
242 | length = pmatch[0].rm_eo; | |
243 | } | |
244 | else | |
245 | { | |
246 | start = 0; | |
247 | length = strlen (string); | |
248 | } | |
249 | ||
250 | __libc_lock_lock (dfa->lock); | |
251 | if (preg->no_sub) | |
252 | err = re_search_internal (preg, string, length, start, length, | |
253 | length, 0, NULL, eflags); | |
254 | else | |
255 | err = re_search_internal (preg, string, length, start, length, | |
256 | length, nmatch, pmatch, eflags); | |
257 | __libc_lock_unlock (dfa->lock); | |
258 | return err != REG_NOERROR; | |
259 | } | |
260 | ||
261 | #ifdef _LIBC | |
262 | # include <shlib-compat.h> | |
263 | versioned_symbol (libc, __regexec, regexec, GLIBC_2_3_4); | |
264 | ||
265 | # if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_3_4) | |
266 | __typeof__ (__regexec) __compat_regexec; | |
267 | ||
268 | int | |
269 | attribute_compat_text_section | |
270 | __compat_regexec (const regex_t *_Restrict_ preg, | |
271 | const char *_Restrict_ string, size_t nmatch, | |
272 | regmatch_t pmatch[], int eflags) | |
273 | { | |
274 | return regexec (preg, string, nmatch, pmatch, | |
275 | eflags & (REG_NOTBOL | REG_NOTEOL)); | |
276 | } | |
277 | compat_symbol (libc, __compat_regexec, regexec, GLIBC_2_0); | |
278 | # endif | |
279 | #endif | |
280 | ||
281 | /* Entry points for GNU code. */ | |
282 | ||
283 | /* re_match, re_search, re_match_2, re_search_2 | |
284 | ||
285 | The former two functions operate on STRING with length LENGTH, | |
286 | while the later two operate on concatenation of STRING1 and STRING2 | |
287 | with lengths LENGTH1 and LENGTH2, respectively. | |
288 | ||
289 | re_match() matches the compiled pattern in BUFP against the string, | |
290 | starting at index START. | |
291 | ||
292 | re_search() first tries matching at index START, then it tries to match | |
293 | starting from index START + 1, and so on. The last start position tried | |
294 | is START + RANGE. (Thus RANGE = 0 forces re_search to operate the same | |
295 | way as re_match().) | |
296 | ||
297 | The parameter STOP of re_{match,search}_2 specifies that no match exceeding | |
298 | the first STOP characters of the concatenation of the strings should be | |
299 | concerned. | |
300 | ||
301 | If REGS is not NULL, and BUFP->no_sub is not set, the offsets of the match | |
302 | and all groups is stored in REGS. (For the "_2" variants, the offsets are | |
303 | computed relative to the concatenation, not relative to the individual | |
304 | strings.) | |
305 | ||
306 | On success, re_match* functions return the length of the match, re_search* | |
307 | return the position of the start of the match. Return value -1 means no | |
308 | match was found and -2 indicates an internal error. */ | |
309 | ||
310 | regoff_t | |
311 | re_match (bufp, string, length, start, regs) | |
312 | struct re_pattern_buffer *bufp; | |
313 | const char *string; | |
314 | Idx length, start; | |
315 | struct re_registers *regs; | |
316 | { | |
317 | return re_search_stub (bufp, string, length, start, 0, length, regs, true); | |
318 | } | |
319 | #ifdef _LIBC | |
320 | weak_alias (__re_match, re_match) | |
321 | #endif | |
322 | ||
323 | regoff_t | |
324 | re_search (bufp, string, length, start, range, regs) | |
325 | struct re_pattern_buffer *bufp; | |
326 | const char *string; | |
327 | Idx length, start; | |
328 | regoff_t range; | |
329 | struct re_registers *regs; | |
330 | { | |
331 | return re_search_stub (bufp, string, length, start, range, length, regs, | |
332 | false); | |
333 | } | |
334 | #ifdef _LIBC | |
335 | weak_alias (__re_search, re_search) | |
336 | #endif | |
337 | ||
338 | regoff_t | |
339 | re_match_2 (bufp, string1, length1, string2, length2, start, regs, stop) | |
340 | struct re_pattern_buffer *bufp; | |
341 | const char *string1, *string2; | |
342 | Idx length1, length2, start, stop; | |
343 | struct re_registers *regs; | |
344 | { | |
345 | return re_search_2_stub (bufp, string1, length1, string2, length2, | |
346 | start, 0, regs, stop, true); | |
347 | } | |
348 | #ifdef _LIBC | |
349 | weak_alias (__re_match_2, re_match_2) | |
350 | #endif | |
351 | ||
352 | regoff_t | |
353 | re_search_2 (bufp, string1, length1, string2, length2, start, range, regs, stop) | |
354 | struct re_pattern_buffer *bufp; | |
355 | const char *string1, *string2; | |
356 | Idx length1, length2, start, stop; | |
357 | regoff_t range; | |
358 | struct re_registers *regs; | |
359 | { | |
360 | return re_search_2_stub (bufp, string1, length1, string2, length2, | |
361 | start, range, regs, stop, false); | |
362 | } | |
363 | #ifdef _LIBC | |
364 | weak_alias (__re_search_2, re_search_2) | |
365 | #endif | |
366 | ||
367 | static regoff_t | |
368 | internal_function | |
369 | re_search_2_stub (struct re_pattern_buffer *bufp, | |
370 | const char *string1, Idx length1, | |
371 | const char *string2, Idx length2, | |
372 | Idx start, regoff_t range, struct re_registers *regs, | |
373 | Idx stop, bool ret_len) | |
374 | { | |
375 | const char *str; | |
376 | regoff_t rval; | |
377 | Idx len = length1 + length2; | |
378 | char *s = NULL; | |
379 | ||
380 | if (BE (length1 < 0 || length2 < 0 || stop < 0 || len < length1, 0)) | |
381 | return -2; | |
382 | ||
383 | /* Concatenate the strings. */ | |
384 | if (length2 > 0) | |
385 | if (length1 > 0) | |
386 | { | |
387 | s = re_malloc (char, len); | |
388 | ||
389 | if (BE (s == NULL, 0)) | |
390 | return -2; | |
391 | #ifdef _LIBC | |
392 | memcpy (__mempcpy (s, string1, length1), string2, length2); | |
393 | #else | |
394 | memcpy (s, string1, length1); | |
395 | memcpy (s + length1, string2, length2); | |
396 | #endif | |
397 | str = s; | |
398 | } | |
399 | else | |
400 | str = string2; | |
401 | else | |
402 | str = string1; | |
403 | ||
404 | rval = re_search_stub (bufp, str, len, start, range, stop, regs, | |
405 | ret_len); | |
406 | re_free (s); | |
407 | return rval; | |
408 | } | |
409 | ||
410 | /* The parameters have the same meaning as those of re_search. | |
411 | Additional parameters: | |
412 | If RET_LEN is true the length of the match is returned (re_match style); | |
413 | otherwise the position of the match is returned. */ | |
414 | ||
415 | static regoff_t | |
416 | internal_function | |
417 | re_search_stub (struct re_pattern_buffer *bufp, | |
418 | const char *string, Idx length, | |
419 | Idx start, regoff_t range, Idx stop, struct re_registers *regs, | |
420 | bool ret_len) | |
421 | { | |
422 | reg_errcode_t result; | |
423 | regmatch_t *pmatch; | |
424 | Idx nregs; | |
425 | regoff_t rval; | |
426 | int eflags = 0; | |
427 | #ifdef _LIBC | |
428 | re_dfa_t *dfa = (re_dfa_t *) bufp->buffer; | |
429 | #endif | |
430 | Idx last_start = start + range; | |
431 | ||
432 | /* Check for out-of-range. */ | |
433 | if (BE (start < 0 || start > length, 0)) | |
434 | return -1; | |
435 | if (BE (length < last_start || (0 <= range && last_start < start), 0)) | |
436 | last_start = length; | |
437 | else if (BE (last_start < 0 || (range < 0 && start <= last_start), 0)) | |
438 | last_start = 0; | |
439 | ||
440 | __libc_lock_lock (dfa->lock); | |
441 | ||
442 | eflags |= (bufp->not_bol) ? REG_NOTBOL : 0; | |
443 | eflags |= (bufp->not_eol) ? REG_NOTEOL : 0; | |
444 | ||
445 | /* Compile fastmap if we haven't yet. */ | |
446 | if (start < last_start && bufp->fastmap != NULL && !bufp->fastmap_accurate) | |
447 | re_compile_fastmap (bufp); | |
448 | ||
449 | if (BE (bufp->no_sub, 0)) | |
450 | regs = NULL; | |
451 | ||
452 | /* We need at least 1 register. */ | |
453 | if (regs == NULL) | |
454 | nregs = 1; | |
455 | else if (BE (bufp->regs_allocated == REGS_FIXED | |
456 | && regs->num_regs <= bufp->re_nsub, 0)) | |
457 | { | |
458 | nregs = regs->num_regs; | |
459 | if (BE (nregs < 1, 0)) | |
460 | { | |
461 | /* Nothing can be copied to regs. */ | |
462 | regs = NULL; | |
463 | nregs = 1; | |
464 | } | |
465 | } | |
466 | else | |
467 | nregs = bufp->re_nsub + 1; | |
468 | pmatch = re_malloc (regmatch_t, nregs); | |
469 | if (BE (pmatch == NULL, 0)) | |
470 | { | |
471 | rval = -2; | |
472 | goto out; | |
473 | } | |
474 | ||
475 | result = re_search_internal (bufp, string, length, start, last_start, stop, | |
476 | nregs, pmatch, eflags); | |
477 | ||
478 | rval = 0; | |
479 | ||
480 | /* I hope we needn't fill ther regs with -1's when no match was found. */ | |
481 | if (result != REG_NOERROR) | |
482 | rval = -1; | |
483 | else if (regs != NULL) | |
484 | { | |
485 | /* If caller wants register contents data back, copy them. */ | |
486 | bufp->regs_allocated = re_copy_regs (regs, pmatch, nregs, | |
487 | bufp->regs_allocated); | |
488 | if (BE (bufp->regs_allocated == REGS_UNALLOCATED, 0)) | |
489 | rval = -2; | |
490 | } | |
491 | ||
492 | if (BE (rval == 0, 1)) | |
493 | { | |
494 | if (ret_len) | |
495 | { | |
496 | assert (pmatch[0].rm_so == start); | |
497 | rval = pmatch[0].rm_eo - start; | |
498 | } | |
499 | else | |
500 | rval = pmatch[0].rm_so; | |
501 | } | |
502 | re_free (pmatch); | |
503 | out: | |
504 | __libc_lock_unlock (dfa->lock); | |
505 | return rval; | |
506 | } | |
507 | ||
508 | static unsigned int | |
509 | internal_function | |
510 | re_copy_regs (struct re_registers *regs, regmatch_t *pmatch, Idx nregs, | |
511 | int regs_allocated) | |
512 | { | |
513 | int rval = REGS_REALLOCATE; | |
514 | Idx i; | |
515 | Idx need_regs = nregs + 1; | |
516 | /* We need one extra element beyond 'num_regs' for the '-1' marker GNU code | |
517 | uses. */ | |
518 | ||
519 | /* Have the register data arrays been allocated? */ | |
520 | if (regs_allocated == REGS_UNALLOCATED) | |
521 | { /* No. So allocate them with malloc. */ | |
522 | regs->start = re_malloc (regoff_t, need_regs); | |
523 | if (BE (regs->start == NULL, 0)) | |
524 | return REGS_UNALLOCATED; | |
525 | regs->end = re_malloc (regoff_t, need_regs); | |
526 | if (BE (regs->end == NULL, 0)) | |
527 | { | |
528 | re_free (regs->start); | |
529 | return REGS_UNALLOCATED; | |
530 | } | |
531 | regs->num_regs = need_regs; | |
532 | } | |
533 | else if (regs_allocated == REGS_REALLOCATE) | |
534 | { /* Yes. If we need more elements than were already | |
535 | allocated, reallocate them. If we need fewer, just | |
536 | leave it alone. */ | |
537 | if (BE (need_regs > regs->num_regs, 0)) | |
538 | { | |
539 | regoff_t *new_start = re_realloc (regs->start, regoff_t, need_regs); | |
540 | regoff_t *new_end; | |
541 | if (BE (new_start == NULL, 0)) | |
542 | return REGS_UNALLOCATED; | |
543 | new_end = re_realloc (regs->end, regoff_t, need_regs); | |
544 | if (BE (new_end == NULL, 0)) | |
545 | { | |
546 | re_free (new_start); | |
547 | return REGS_UNALLOCATED; | |
548 | } | |
549 | regs->start = new_start; | |
550 | regs->end = new_end; | |
551 | regs->num_regs = need_regs; | |
552 | } | |
553 | } | |
554 | else | |
555 | { | |
556 | assert (regs_allocated == REGS_FIXED); | |
557 | /* This function may not be called with REGS_FIXED and nregs too big. */ | |
558 | assert (regs->num_regs >= nregs); | |
559 | rval = REGS_FIXED; | |
560 | } | |
561 | ||
562 | /* Copy the regs. */ | |
563 | for (i = 0; i < nregs; ++i) | |
564 | { | |
565 | regs->start[i] = pmatch[i].rm_so; | |
566 | regs->end[i] = pmatch[i].rm_eo; | |
567 | } | |
568 | for ( ; i < regs->num_regs; ++i) | |
569 | regs->start[i] = regs->end[i] = -1; | |
570 | ||
571 | return rval; | |
572 | } | |
573 | ||
574 | /* Set REGS to hold NUM_REGS registers, storing them in STARTS and | |
575 | ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use | |
576 | this memory for recording register information. STARTS and ENDS | |
577 | must be allocated using the malloc library routine, and must each | |
578 | be at least NUM_REGS * sizeof (regoff_t) bytes long. | |
579 | ||
580 | If NUM_REGS == 0, then subsequent matches should allocate their own | |
581 | register data. | |
582 | ||
583 | Unless this function is called, the first search or match using | |
584 | PATTERN_BUFFER will allocate its own register data, without | |
585 | freeing the old data. */ | |
586 | ||
587 | void | |
588 | re_set_registers (bufp, regs, num_regs, starts, ends) | |
589 | struct re_pattern_buffer *bufp; | |
590 | struct re_registers *regs; | |
591 | __re_size_t num_regs; | |
592 | regoff_t *starts, *ends; | |
593 | { | |
594 | if (num_regs) | |
595 | { | |
596 | bufp->regs_allocated = REGS_REALLOCATE; | |
597 | regs->num_regs = num_regs; | |
598 | regs->start = starts; | |
599 | regs->end = ends; | |
600 | } | |
601 | else | |
602 | { | |
603 | bufp->regs_allocated = REGS_UNALLOCATED; | |
604 | regs->num_regs = 0; | |
605 | regs->start = regs->end = NULL; | |
606 | } | |
607 | } | |
608 | #ifdef _LIBC | |
609 | weak_alias (__re_set_registers, re_set_registers) | |
610 | #endif | |
611 | \f | |
612 | /* Entry points compatible with 4.2 BSD regex library. We don't define | |
613 | them unless specifically requested. */ | |
614 | ||
615 | #if defined _REGEX_RE_COMP || defined _LIBC | |
616 | int | |
617 | # ifdef _LIBC | |
618 | weak_function | |
619 | # endif | |
620 | re_exec (s) | |
621 | const char *s; | |
622 | { | |
623 | return 0 == regexec (&re_comp_buf, s, 0, NULL, 0); | |
624 | } | |
625 | #endif /* _REGEX_RE_COMP */ | |
626 | \f | |
627 | /* Internal entry point. */ | |
628 | ||
629 | /* Searches for a compiled pattern PREG in the string STRING, whose | |
630 | length is LENGTH. NMATCH, PMATCH, and EFLAGS have the same | |
631 | meaning as with regexec. LAST_START is START + RANGE, where | |
632 | START and RANGE have the same meaning as with re_search. | |
633 | Return REG_NOERROR if we find a match, and REG_NOMATCH if not, | |
634 | otherwise return the error code. | |
635 | Note: We assume front end functions already check ranges. | |
636 | (0 <= LAST_START && LAST_START <= LENGTH) */ | |
637 | ||
638 | static reg_errcode_t | |
639 | internal_function __attribute_warn_unused_result__ | |
640 | re_search_internal (const regex_t *preg, | |
641 | const char *string, Idx length, | |
642 | Idx start, Idx last_start, Idx stop, | |
643 | size_t nmatch, regmatch_t pmatch[], | |
644 | int eflags) | |
645 | { | |
646 | reg_errcode_t err; | |
647 | const re_dfa_t *dfa = (const re_dfa_t *) preg->buffer; | |
648 | Idx left_lim, right_lim; | |
649 | int incr; | |
650 | bool fl_longest_match; | |
651 | int match_kind; | |
652 | Idx match_first; | |
653 | Idx match_last = REG_MISSING; | |
654 | Idx extra_nmatch; | |
655 | bool sb; | |
656 | int ch; | |
657 | #if defined _LIBC || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L) | |
658 | re_match_context_t mctx = { .dfa = dfa }; | |
659 | #else | |
660 | re_match_context_t mctx; | |
661 | #endif | |
662 | char *fastmap = ((preg->fastmap != NULL && preg->fastmap_accurate | |
663 | && start != last_start && !preg->can_be_null) | |
664 | ? preg->fastmap : NULL); | |
665 | RE_TRANSLATE_TYPE t = preg->translate; | |
666 | ||
667 | #if !(defined _LIBC || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)) | |
668 | memset (&mctx, '\0', sizeof (re_match_context_t)); | |
669 | mctx.dfa = dfa; | |
670 | #endif | |
671 | ||
672 | extra_nmatch = (nmatch > preg->re_nsub) ? nmatch - (preg->re_nsub + 1) : 0; | |
673 | nmatch -= extra_nmatch; | |
674 | ||
675 | /* Check if the DFA haven't been compiled. */ | |
676 | if (BE (preg->used == 0 || dfa->init_state == NULL | |
677 | || dfa->init_state_word == NULL || dfa->init_state_nl == NULL | |
678 | || dfa->init_state_begbuf == NULL, 0)) | |
679 | return REG_NOMATCH; | |
680 | ||
681 | #ifdef DEBUG | |
682 | /* We assume front-end functions already check them. */ | |
683 | assert (0 <= last_start && last_start <= length); | |
684 | #endif | |
685 | ||
686 | /* If initial states with non-begbuf contexts have no elements, | |
687 | the regex must be anchored. If preg->newline_anchor is set, | |
688 | we'll never use init_state_nl, so do not check it. */ | |
689 | if (dfa->init_state->nodes.nelem == 0 | |
690 | && dfa->init_state_word->nodes.nelem == 0 | |
691 | && (dfa->init_state_nl->nodes.nelem == 0 | |
692 | || !preg->newline_anchor)) | |
693 | { | |
694 | if (start != 0 && last_start != 0) | |
695 | return REG_NOMATCH; | |
696 | start = last_start = 0; | |
697 | } | |
698 | ||
699 | /* We must check the longest matching, if nmatch > 0. */ | |
700 | fl_longest_match = (nmatch != 0 || dfa->nbackref); | |
701 | ||
702 | err = re_string_allocate (&mctx.input, string, length, dfa->nodes_len + 1, | |
703 | preg->translate, (preg->syntax & RE_ICASE) != 0, | |
704 | dfa); | |
705 | if (BE (err != REG_NOERROR, 0)) | |
706 | goto free_return; | |
707 | mctx.input.stop = stop; | |
708 | mctx.input.raw_stop = stop; | |
709 | mctx.input.newline_anchor = preg->newline_anchor; | |
710 | ||
711 | err = match_ctx_init (&mctx, eflags, dfa->nbackref * 2); | |
712 | if (BE (err != REG_NOERROR, 0)) | |
713 | goto free_return; | |
714 | ||
715 | /* We will log all the DFA states through which the dfa pass, | |
716 | if nmatch > 1, or this dfa has "multibyte node", which is a | |
717 | back-reference or a node which can accept multibyte character or | |
718 | multi character collating element. */ | |
719 | if (nmatch > 1 || dfa->has_mb_node) | |
720 | { | |
721 | /* Avoid overflow. */ | |
722 | if (BE (SIZE_MAX / sizeof (re_dfastate_t *) <= mctx.input.bufs_len, 0)) | |
723 | { | |
724 | err = REG_ESPACE; | |
725 | goto free_return; | |
726 | } | |
727 | ||
728 | mctx.state_log = re_malloc (re_dfastate_t *, mctx.input.bufs_len + 1); | |
729 | if (BE (mctx.state_log == NULL, 0)) | |
730 | { | |
731 | err = REG_ESPACE; | |
732 | goto free_return; | |
733 | } | |
734 | } | |
735 | else | |
736 | mctx.state_log = NULL; | |
737 | ||
738 | match_first = start; | |
739 | mctx.input.tip_context = (eflags & REG_NOTBOL) ? CONTEXT_BEGBUF | |
740 | : CONTEXT_NEWLINE | CONTEXT_BEGBUF; | |
741 | ||
742 | /* Check incrementally whether of not the input string match. */ | |
743 | incr = (last_start < start) ? -1 : 1; | |
744 | left_lim = (last_start < start) ? last_start : start; | |
745 | right_lim = (last_start < start) ? start : last_start; | |
746 | sb = dfa->mb_cur_max == 1; | |
747 | match_kind = | |
748 | (fastmap | |
749 | ? ((sb || !(preg->syntax & RE_ICASE || t) ? 4 : 0) | |
750 | | (start <= last_start ? 2 : 0) | |
751 | | (t != NULL ? 1 : 0)) | |
752 | : 8); | |
753 | ||
754 | for (;; match_first += incr) | |
755 | { | |
756 | err = REG_NOMATCH; | |
757 | if (match_first < left_lim || right_lim < match_first) | |
758 | goto free_return; | |
759 | ||
760 | /* Advance as rapidly as possible through the string, until we | |
761 | find a plausible place to start matching. This may be done | |
762 | with varying efficiency, so there are various possibilities: | |
763 | only the most common of them are specialized, in order to | |
764 | save on code size. We use a switch statement for speed. */ | |
765 | switch (match_kind) | |
766 | { | |
767 | case 8: | |
768 | /* No fastmap. */ | |
769 | break; | |
770 | ||
771 | case 7: | |
772 | /* Fastmap with single-byte translation, match forward. */ | |
773 | while (BE (match_first < right_lim, 1) | |
774 | && !fastmap[t[(unsigned char) string[match_first]]]) | |
775 | ++match_first; | |
776 | goto forward_match_found_start_or_reached_end; | |
777 | ||
778 | case 6: | |
779 | /* Fastmap without translation, match forward. */ | |
780 | while (BE (match_first < right_lim, 1) | |
781 | && !fastmap[(unsigned char) string[match_first]]) | |
782 | ++match_first; | |
783 | ||
784 | forward_match_found_start_or_reached_end: | |
785 | if (BE (match_first == right_lim, 0)) | |
786 | { | |
787 | ch = match_first >= length | |
788 | ? 0 : (unsigned char) string[match_first]; | |
789 | if (!fastmap[t ? t[ch] : ch]) | |
790 | goto free_return; | |
791 | } | |
792 | break; | |
793 | ||
794 | case 4: | |
795 | case 5: | |
796 | /* Fastmap without multi-byte translation, match backwards. */ | |
797 | while (match_first >= left_lim) | |
798 | { | |
799 | ch = match_first >= length | |
800 | ? 0 : (unsigned char) string[match_first]; | |
801 | if (fastmap[t ? t[ch] : ch]) | |
802 | break; | |
803 | --match_first; | |
804 | } | |
805 | if (match_first < left_lim) | |
806 | goto free_return; | |
807 | break; | |
808 | ||
809 | default: | |
810 | /* In this case, we can't determine easily the current byte, | |
811 | since it might be a component byte of a multibyte | |
812 | character. Then we use the constructed buffer instead. */ | |
813 | for (;;) | |
814 | { | |
815 | /* If MATCH_FIRST is out of the valid range, reconstruct the | |
816 | buffers. */ | |
817 | __re_size_t offset = match_first - mctx.input.raw_mbs_idx; | |
818 | if (BE (offset >= (__re_size_t) mctx.input.valid_raw_len, 0)) | |
819 | { | |
820 | err = re_string_reconstruct (&mctx.input, match_first, | |
821 | eflags); | |
822 | if (BE (err != REG_NOERROR, 0)) | |
823 | goto free_return; | |
824 | ||
825 | offset = match_first - mctx.input.raw_mbs_idx; | |
826 | } | |
827 | /* If MATCH_FIRST is out of the buffer, leave it as '\0'. | |
828 | Note that MATCH_FIRST must not be smaller than 0. */ | |
829 | ch = (match_first >= length | |
830 | ? 0 : re_string_byte_at (&mctx.input, offset)); | |
831 | if (fastmap[ch]) | |
832 | break; | |
833 | match_first += incr; | |
834 | if (match_first < left_lim || match_first > right_lim) | |
835 | { | |
836 | err = REG_NOMATCH; | |
837 | goto free_return; | |
838 | } | |
839 | } | |
840 | break; | |
841 | } | |
842 | ||
843 | /* Reconstruct the buffers so that the matcher can assume that | |
844 | the matching starts from the beginning of the buffer. */ | |
845 | err = re_string_reconstruct (&mctx.input, match_first, eflags); | |
846 | if (BE (err != REG_NOERROR, 0)) | |
847 | goto free_return; | |
848 | ||
849 | #ifdef RE_ENABLE_I18N | |
850 | /* Don't consider this char as a possible match start if it part, | |
851 | yet isn't the head, of a multibyte character. */ | |
852 | if (!sb && !re_string_first_byte (&mctx.input, 0)) | |
853 | continue; | |
854 | #endif | |
855 | ||
856 | /* It seems to be appropriate one, then use the matcher. */ | |
857 | /* We assume that the matching starts from 0. */ | |
858 | mctx.state_log_top = mctx.nbkref_ents = mctx.max_mb_elem_len = 0; | |
859 | match_last = check_matching (&mctx, fl_longest_match, | |
860 | start <= last_start ? &match_first : NULL); | |
861 | if (match_last != REG_MISSING) | |
862 | { | |
863 | if (BE (match_last == REG_ERROR, 0)) | |
864 | { | |
865 | err = REG_ESPACE; | |
866 | goto free_return; | |
867 | } | |
868 | else | |
869 | { | |
870 | mctx.match_last = match_last; | |
871 | if ((!preg->no_sub && nmatch > 1) || dfa->nbackref) | |
872 | { | |
873 | re_dfastate_t *pstate = mctx.state_log[match_last]; | |
874 | mctx.last_node = check_halt_state_context (&mctx, pstate, | |
875 | match_last); | |
876 | } | |
877 | if ((!preg->no_sub && nmatch > 1 && dfa->has_plural_match) | |
878 | || dfa->nbackref) | |
879 | { | |
880 | err = prune_impossible_nodes (&mctx); | |
881 | if (err == REG_NOERROR) | |
882 | break; | |
883 | if (BE (err != REG_NOMATCH, 0)) | |
884 | goto free_return; | |
885 | match_last = REG_MISSING; | |
886 | } | |
887 | else | |
888 | break; /* We found a match. */ | |
889 | } | |
890 | } | |
891 | ||
892 | match_ctx_clean (&mctx); | |
893 | } | |
894 | ||
895 | #ifdef DEBUG | |
896 | assert (match_last != REG_MISSING); | |
897 | assert (err == REG_NOERROR); | |
898 | #endif | |
899 | ||
900 | /* Set pmatch[] if we need. */ | |
901 | if (nmatch > 0) | |
902 | { | |
903 | Idx reg_idx; | |
904 | ||
905 | /* Initialize registers. */ | |
906 | for (reg_idx = 1; reg_idx < nmatch; ++reg_idx) | |
907 | pmatch[reg_idx].rm_so = pmatch[reg_idx].rm_eo = -1; | |
908 | ||
909 | /* Set the points where matching start/end. */ | |
910 | pmatch[0].rm_so = 0; | |
911 | pmatch[0].rm_eo = mctx.match_last; | |
912 | /* FIXME: This function should fail if mctx.match_last exceeds | |
913 | the maximum possible regoff_t value. We need a new error | |
914 | code REG_OVERFLOW. */ | |
915 | ||
916 | if (!preg->no_sub && nmatch > 1) | |
917 | { | |
918 | err = set_regs (preg, &mctx, nmatch, pmatch, | |
919 | dfa->has_plural_match && dfa->nbackref > 0); | |
920 | if (BE (err != REG_NOERROR, 0)) | |
921 | goto free_return; | |
922 | } | |
923 | ||
924 | /* At last, add the offset to the each registers, since we slided | |
925 | the buffers so that we could assume that the matching starts | |
926 | from 0. */ | |
927 | for (reg_idx = 0; reg_idx < nmatch; ++reg_idx) | |
928 | if (pmatch[reg_idx].rm_so != -1) | |
929 | { | |
930 | #ifdef RE_ENABLE_I18N | |
931 | if (BE (mctx.input.offsets_needed != 0, 0)) | |
932 | { | |
933 | pmatch[reg_idx].rm_so = | |
934 | (pmatch[reg_idx].rm_so == mctx.input.valid_len | |
935 | ? mctx.input.valid_raw_len | |
936 | : mctx.input.offsets[pmatch[reg_idx].rm_so]); | |
937 | pmatch[reg_idx].rm_eo = | |
938 | (pmatch[reg_idx].rm_eo == mctx.input.valid_len | |
939 | ? mctx.input.valid_raw_len | |
940 | : mctx.input.offsets[pmatch[reg_idx].rm_eo]); | |
941 | } | |
942 | #else | |
943 | assert (mctx.input.offsets_needed == 0); | |
944 | #endif | |
945 | pmatch[reg_idx].rm_so += match_first; | |
946 | pmatch[reg_idx].rm_eo += match_first; | |
947 | } | |
948 | for (reg_idx = 0; reg_idx < extra_nmatch; ++reg_idx) | |
949 | { | |
950 | pmatch[nmatch + reg_idx].rm_so = -1; | |
951 | pmatch[nmatch + reg_idx].rm_eo = -1; | |
952 | } | |
953 | ||
954 | if (dfa->subexp_map) | |
955 | for (reg_idx = 0; reg_idx + 1 < nmatch; reg_idx++) | |
956 | if (dfa->subexp_map[reg_idx] != reg_idx) | |
957 | { | |
958 | pmatch[reg_idx + 1].rm_so | |
959 | = pmatch[dfa->subexp_map[reg_idx] + 1].rm_so; | |
960 | pmatch[reg_idx + 1].rm_eo | |
961 | = pmatch[dfa->subexp_map[reg_idx] + 1].rm_eo; | |
962 | } | |
963 | } | |
964 | ||
965 | free_return: | |
966 | re_free (mctx.state_log); | |
967 | if (dfa->nbackref) | |
968 | match_ctx_free (&mctx); | |
969 | re_string_destruct (&mctx.input); | |
970 | return err; | |
971 | } | |
972 | ||
973 | static reg_errcode_t | |
974 | internal_function __attribute_warn_unused_result__ | |
975 | prune_impossible_nodes (re_match_context_t *mctx) | |
976 | { | |
977 | const re_dfa_t *const dfa = mctx->dfa; | |
978 | Idx halt_node, match_last; | |
979 | reg_errcode_t ret; | |
980 | re_dfastate_t **sifted_states; | |
981 | re_dfastate_t **lim_states = NULL; | |
982 | re_sift_context_t sctx; | |
983 | #ifdef DEBUG | |
984 | assert (mctx->state_log != NULL); | |
985 | #endif | |
986 | match_last = mctx->match_last; | |
987 | halt_node = mctx->last_node; | |
988 | ||
989 | /* Avoid overflow. */ | |
990 | if (BE (SIZE_MAX / sizeof (re_dfastate_t *) <= match_last, 0)) | |
991 | return REG_ESPACE; | |
992 | ||
993 | sifted_states = re_malloc (re_dfastate_t *, match_last + 1); | |
994 | if (BE (sifted_states == NULL, 0)) | |
995 | { | |
996 | ret = REG_ESPACE; | |
997 | goto free_return; | |
998 | } | |
999 | if (dfa->nbackref) | |
1000 | { | |
1001 | lim_states = re_malloc (re_dfastate_t *, match_last + 1); | |
1002 | if (BE (lim_states == NULL, 0)) | |
1003 | { | |
1004 | ret = REG_ESPACE; | |
1005 | goto free_return; | |
1006 | } | |
1007 | while (1) | |
1008 | { | |
1009 | memset (lim_states, '\0', | |
1010 | sizeof (re_dfastate_t *) * (match_last + 1)); | |
1011 | sift_ctx_init (&sctx, sifted_states, lim_states, halt_node, | |
1012 | match_last); | |
1013 | ret = sift_states_backward (mctx, &sctx); | |
1014 | re_node_set_free (&sctx.limits); | |
1015 | if (BE (ret != REG_NOERROR, 0)) | |
1016 | goto free_return; | |
1017 | if (sifted_states[0] != NULL || lim_states[0] != NULL) | |
1018 | break; | |
1019 | do | |
1020 | { | |
1021 | --match_last; | |
1022 | if (! REG_VALID_INDEX (match_last)) | |
1023 | { | |
1024 | ret = REG_NOMATCH; | |
1025 | goto free_return; | |
1026 | } | |
1027 | } while (mctx->state_log[match_last] == NULL | |
1028 | || !mctx->state_log[match_last]->halt); | |
1029 | halt_node = check_halt_state_context (mctx, | |
1030 | mctx->state_log[match_last], | |
1031 | match_last); | |
1032 | } | |
1033 | ret = merge_state_array (dfa, sifted_states, lim_states, | |
1034 | match_last + 1); | |
1035 | re_free (lim_states); | |
1036 | lim_states = NULL; | |
1037 | if (BE (ret != REG_NOERROR, 0)) | |
1038 | goto free_return; | |
1039 | } | |
1040 | else | |
1041 | { | |
1042 | sift_ctx_init (&sctx, sifted_states, lim_states, halt_node, match_last); | |
1043 | ret = sift_states_backward (mctx, &sctx); | |
1044 | re_node_set_free (&sctx.limits); | |
1045 | if (BE (ret != REG_NOERROR, 0)) | |
1046 | goto free_return; | |
1047 | if (sifted_states[0] == NULL) | |
1048 | { | |
1049 | ret = REG_NOMATCH; | |
1050 | goto free_return; | |
1051 | } | |
1052 | } | |
1053 | re_free (mctx->state_log); | |
1054 | mctx->state_log = sifted_states; | |
1055 | sifted_states = NULL; | |
1056 | mctx->last_node = halt_node; | |
1057 | mctx->match_last = match_last; | |
1058 | ret = REG_NOERROR; | |
1059 | free_return: | |
1060 | re_free (sifted_states); | |
1061 | re_free (lim_states); | |
1062 | return ret; | |
1063 | } | |
1064 | ||
1065 | /* Acquire an initial state and return it. | |
1066 | We must select appropriate initial state depending on the context, | |
1067 | since initial states may have constraints like "\<", "^", etc.. */ | |
1068 | ||
1069 | static inline re_dfastate_t * | |
1070 | __attribute ((always_inline)) internal_function | |
1071 | acquire_init_state_context (reg_errcode_t *err, const re_match_context_t *mctx, | |
1072 | Idx idx) | |
1073 | { | |
1074 | const re_dfa_t *const dfa = mctx->dfa; | |
1075 | if (dfa->init_state->has_constraint) | |
1076 | { | |
1077 | unsigned int context; | |
1078 | context = re_string_context_at (&mctx->input, idx - 1, mctx->eflags); | |
1079 | if (IS_WORD_CONTEXT (context)) | |
1080 | return dfa->init_state_word; | |
1081 | else if (IS_ORDINARY_CONTEXT (context)) | |
1082 | return dfa->init_state; | |
1083 | else if (IS_BEGBUF_CONTEXT (context) && IS_NEWLINE_CONTEXT (context)) | |
1084 | return dfa->init_state_begbuf; | |
1085 | else if (IS_NEWLINE_CONTEXT (context)) | |
1086 | return dfa->init_state_nl; | |
1087 | else if (IS_BEGBUF_CONTEXT (context)) | |
1088 | { | |
1089 | /* It is relatively rare case, then calculate on demand. */ | |
1090 | return re_acquire_state_context (err, dfa, | |
1091 | dfa->init_state->entrance_nodes, | |
1092 | context); | |
1093 | } | |
1094 | else | |
1095 | /* Must not happen? */ | |
1096 | return dfa->init_state; | |
1097 | } | |
1098 | else | |
1099 | return dfa->init_state; | |
1100 | } | |
1101 | ||
1102 | /* Check whether the regular expression match input string INPUT or not, | |
1103 | and return the index where the matching end. Return REG_MISSING if | |
1104 | there is no match, and return REG_ERROR in case of an error. | |
1105 | FL_LONGEST_MATCH means we want the POSIX longest matching. | |
1106 | If P_MATCH_FIRST is not NULL, and the match fails, it is set to the | |
1107 | next place where we may want to try matching. | |
1108 | Note that the matcher assume that the maching starts from the current | |
1109 | index of the buffer. */ | |
1110 | ||
1111 | static Idx | |
1112 | internal_function __attribute_warn_unused_result__ | |
1113 | check_matching (re_match_context_t *mctx, bool fl_longest_match, | |
1114 | Idx *p_match_first) | |
1115 | { | |
1116 | const re_dfa_t *const dfa = mctx->dfa; | |
1117 | reg_errcode_t err; | |
1118 | Idx match = 0; | |
1119 | Idx match_last = REG_MISSING; | |
1120 | Idx cur_str_idx = re_string_cur_idx (&mctx->input); | |
1121 | re_dfastate_t *cur_state; | |
1122 | bool at_init_state = p_match_first != NULL; | |
1123 | Idx next_start_idx = cur_str_idx; | |
1124 | ||
1125 | err = REG_NOERROR; | |
1126 | cur_state = acquire_init_state_context (&err, mctx, cur_str_idx); | |
1127 | /* An initial state must not be NULL (invalid). */ | |
1128 | if (BE (cur_state == NULL, 0)) | |
1129 | { | |
1130 | assert (err == REG_ESPACE); | |
1131 | return REG_ERROR; | |
1132 | } | |
1133 | ||
1134 | if (mctx->state_log != NULL) | |
1135 | { | |
1136 | mctx->state_log[cur_str_idx] = cur_state; | |
1137 | ||
1138 | /* Check OP_OPEN_SUBEXP in the initial state in case that we use them | |
1139 | later. E.g. Processing back references. */ | |
1140 | if (BE (dfa->nbackref, 0)) | |
1141 | { | |
1142 | at_init_state = false; | |
1143 | err = check_subexp_matching_top (mctx, &cur_state->nodes, 0); | |
1144 | if (BE (err != REG_NOERROR, 0)) | |
1145 | return err; | |
1146 | ||
1147 | if (cur_state->has_backref) | |
1148 | { | |
1149 | err = transit_state_bkref (mctx, &cur_state->nodes); | |
1150 | if (BE (err != REG_NOERROR, 0)) | |
1151 | return err; | |
1152 | } | |
1153 | } | |
1154 | } | |
1155 | ||
1156 | /* If the RE accepts NULL string. */ | |
1157 | if (BE (cur_state->halt, 0)) | |
1158 | { | |
1159 | if (!cur_state->has_constraint | |
1160 | || check_halt_state_context (mctx, cur_state, cur_str_idx)) | |
1161 | { | |
1162 | if (!fl_longest_match) | |
1163 | return cur_str_idx; | |
1164 | else | |
1165 | { | |
1166 | match_last = cur_str_idx; | |
1167 | match = 1; | |
1168 | } | |
1169 | } | |
1170 | } | |
1171 | ||
1172 | while (!re_string_eoi (&mctx->input)) | |
1173 | { | |
1174 | re_dfastate_t *old_state = cur_state; | |
1175 | Idx next_char_idx = re_string_cur_idx (&mctx->input) + 1; | |
1176 | ||
1177 | if (BE (next_char_idx >= mctx->input.bufs_len, 0) | |
1178 | || (BE (next_char_idx >= mctx->input.valid_len, 0) | |
1179 | && mctx->input.valid_len < mctx->input.len)) | |
1180 | { | |
1181 | err = extend_buffers (mctx); | |
1182 | if (BE (err != REG_NOERROR, 0)) | |
1183 | { | |
1184 | assert (err == REG_ESPACE); | |
1185 | return REG_ERROR; | |
1186 | } | |
1187 | } | |
1188 | ||
1189 | cur_state = transit_state (&err, mctx, cur_state); | |
1190 | if (mctx->state_log != NULL) | |
1191 | cur_state = merge_state_with_log (&err, mctx, cur_state); | |
1192 | ||
1193 | if (cur_state == NULL) | |
1194 | { | |
1195 | /* Reached the invalid state or an error. Try to recover a valid | |
1196 | state using the state log, if available and if we have not | |
1197 | already found a valid (even if not the longest) match. */ | |
1198 | if (BE (err != REG_NOERROR, 0)) | |
1199 | return REG_ERROR; | |
1200 | ||
1201 | if (mctx->state_log == NULL | |
1202 | || (match && !fl_longest_match) | |
1203 | || (cur_state = find_recover_state (&err, mctx)) == NULL) | |
1204 | break; | |
1205 | } | |
1206 | ||
1207 | if (BE (at_init_state, 0)) | |
1208 | { | |
1209 | if (old_state == cur_state) | |
1210 | next_start_idx = next_char_idx; | |
1211 | else | |
1212 | at_init_state = false; | |
1213 | } | |
1214 | ||
1215 | if (cur_state->halt) | |
1216 | { | |
1217 | /* Reached a halt state. | |
1218 | Check the halt state can satisfy the current context. */ | |
1219 | if (!cur_state->has_constraint | |
1220 | || check_halt_state_context (mctx, cur_state, | |
1221 | re_string_cur_idx (&mctx->input))) | |
1222 | { | |
1223 | /* We found an appropriate halt state. */ | |
1224 | match_last = re_string_cur_idx (&mctx->input); | |
1225 | match = 1; | |
1226 | ||
1227 | /* We found a match, do not modify match_first below. */ | |
1228 | p_match_first = NULL; | |
1229 | if (!fl_longest_match) | |
1230 | break; | |
1231 | } | |
1232 | } | |
1233 | } | |
1234 | ||
1235 | if (p_match_first) | |
1236 | *p_match_first += next_start_idx; | |
1237 | ||
1238 | return match_last; | |
1239 | } | |
1240 | ||
1241 | /* Check NODE match the current context. */ | |
1242 | ||
1243 | static bool | |
1244 | internal_function | |
1245 | check_halt_node_context (const re_dfa_t *dfa, Idx node, unsigned int context) | |
1246 | { | |
1247 | re_token_type_t type = dfa->nodes[node].type; | |
1248 | unsigned int constraint = dfa->nodes[node].constraint; | |
1249 | if (type != END_OF_RE) | |
1250 | return false; | |
1251 | if (!constraint) | |
1252 | return true; | |
1253 | if (NOT_SATISFY_NEXT_CONSTRAINT (constraint, context)) | |
1254 | return false; | |
1255 | return true; | |
1256 | } | |
1257 | ||
1258 | /* Check the halt state STATE match the current context. | |
1259 | Return 0 if not match, if the node, STATE has, is a halt node and | |
1260 | match the context, return the node. */ | |
1261 | ||
1262 | static Idx | |
1263 | internal_function | |
1264 | check_halt_state_context (const re_match_context_t *mctx, | |
1265 | const re_dfastate_t *state, Idx idx) | |
1266 | { | |
1267 | Idx i; | |
1268 | unsigned int context; | |
1269 | #ifdef DEBUG | |
1270 | assert (state->halt); | |
1271 | #endif | |
1272 | context = re_string_context_at (&mctx->input, idx, mctx->eflags); | |
1273 | for (i = 0; i < state->nodes.nelem; ++i) | |
1274 | if (check_halt_node_context (mctx->dfa, state->nodes.elems[i], context)) | |
1275 | return state->nodes.elems[i]; | |
1276 | return 0; | |
1277 | } | |
1278 | ||
1279 | /* Compute the next node to which "NFA" transit from NODE("NFA" is a NFA | |
1280 | corresponding to the DFA). | |
1281 | Return the destination node, and update EPS_VIA_NODES; | |
1282 | return REG_MISSING in case of errors. */ | |
1283 | ||
1284 | static Idx | |
1285 | internal_function | |
1286 | proceed_next_node (const re_match_context_t *mctx, Idx nregs, regmatch_t *regs, | |
1287 | Idx *pidx, Idx node, re_node_set *eps_via_nodes, | |
1288 | struct re_fail_stack_t *fs) | |
1289 | { | |
1290 | const re_dfa_t *const dfa = mctx->dfa; | |
1291 | Idx i; | |
1292 | bool ok; | |
1293 | if (IS_EPSILON_NODE (dfa->nodes[node].type)) | |
1294 | { | |
1295 | re_node_set *cur_nodes = &mctx->state_log[*pidx]->nodes; | |
1296 | re_node_set *edests = &dfa->edests[node]; | |
1297 | Idx dest_node; | |
1298 | ok = re_node_set_insert (eps_via_nodes, node); | |
1299 | if (BE (! ok, 0)) | |
1300 | return REG_ERROR; | |
1301 | /* Pick up a valid destination, or return REG_MISSING if none | |
1302 | is found. */ | |
1303 | for (dest_node = REG_MISSING, i = 0; i < edests->nelem; ++i) | |
1304 | { | |
1305 | Idx candidate = edests->elems[i]; | |
1306 | if (!re_node_set_contains (cur_nodes, candidate)) | |
1307 | continue; | |
1308 | if (dest_node == REG_MISSING) | |
1309 | dest_node = candidate; | |
1310 | ||
1311 | else | |
1312 | { | |
1313 | /* In order to avoid infinite loop like "(a*)*", return the second | |
1314 | epsilon-transition if the first was already considered. */ | |
1315 | if (re_node_set_contains (eps_via_nodes, dest_node)) | |
1316 | return candidate; | |
1317 | ||
1318 | /* Otherwise, push the second epsilon-transition on the fail stack. */ | |
1319 | else if (fs != NULL | |
1320 | && push_fail_stack (fs, *pidx, candidate, nregs, regs, | |
1321 | eps_via_nodes)) | |
1322 | return REG_ERROR; | |
1323 | ||
1324 | /* We know we are going to exit. */ | |
1325 | break; | |
1326 | } | |
1327 | } | |
1328 | return dest_node; | |
1329 | } | |
1330 | else | |
1331 | { | |
1332 | Idx naccepted = 0; | |
1333 | re_token_type_t type = dfa->nodes[node].type; | |
1334 | ||
1335 | #ifdef RE_ENABLE_I18N | |
1336 | if (dfa->nodes[node].accept_mb) | |
1337 | naccepted = check_node_accept_bytes (dfa, node, &mctx->input, *pidx); | |
1338 | else | |
1339 | #endif /* RE_ENABLE_I18N */ | |
1340 | if (type == OP_BACK_REF) | |
1341 | { | |
1342 | Idx subexp_idx = dfa->nodes[node].opr.idx + 1; | |
1343 | naccepted = regs[subexp_idx].rm_eo - regs[subexp_idx].rm_so; | |
1344 | if (fs != NULL) | |
1345 | { | |
1346 | if (regs[subexp_idx].rm_so == -1 || regs[subexp_idx].rm_eo == -1) | |
1347 | return REG_MISSING; | |
1348 | else if (naccepted) | |
1349 | { | |
1350 | char *buf = (char *) re_string_get_buffer (&mctx->input); | |
1351 | if (memcmp (buf + regs[subexp_idx].rm_so, buf + *pidx, | |
1352 | naccepted) != 0) | |
1353 | return REG_MISSING; | |
1354 | } | |
1355 | } | |
1356 | ||
1357 | if (naccepted == 0) | |
1358 | { | |
1359 | Idx dest_node; | |
1360 | ok = re_node_set_insert (eps_via_nodes, node); | |
1361 | if (BE (! ok, 0)) | |
1362 | return REG_ERROR; | |
1363 | dest_node = dfa->edests[node].elems[0]; | |
1364 | if (re_node_set_contains (&mctx->state_log[*pidx]->nodes, | |
1365 | dest_node)) | |
1366 | return dest_node; | |
1367 | } | |
1368 | } | |
1369 | ||
1370 | if (naccepted != 0 | |
1371 | || check_node_accept (mctx, dfa->nodes + node, *pidx)) | |
1372 | { | |
1373 | Idx dest_node = dfa->nexts[node]; | |
1374 | *pidx = (naccepted == 0) ? *pidx + 1 : *pidx + naccepted; | |
1375 | if (fs && (*pidx > mctx->match_last || mctx->state_log[*pidx] == NULL | |
1376 | || !re_node_set_contains (&mctx->state_log[*pidx]->nodes, | |
1377 | dest_node))) | |
1378 | return REG_MISSING; | |
1379 | re_node_set_empty (eps_via_nodes); | |
1380 | return dest_node; | |
1381 | } | |
1382 | } | |
1383 | return REG_MISSING; | |
1384 | } | |
1385 | ||
1386 | static reg_errcode_t | |
1387 | internal_function __attribute_warn_unused_result__ | |
1388 | push_fail_stack (struct re_fail_stack_t *fs, Idx str_idx, Idx dest_node, | |
1389 | Idx nregs, regmatch_t *regs, re_node_set *eps_via_nodes) | |
1390 | { | |
1391 | reg_errcode_t err; | |
1392 | Idx num = fs->num++; | |
1393 | if (fs->num == fs->alloc) | |
1394 | { | |
1395 | struct re_fail_stack_ent_t *new_array; | |
1396 | new_array = realloc (fs->stack, (sizeof (struct re_fail_stack_ent_t) | |
1397 | * fs->alloc * 2)); | |
1398 | if (new_array == NULL) | |
1399 | return REG_ESPACE; | |
1400 | fs->alloc *= 2; | |
1401 | fs->stack = new_array; | |
1402 | } | |
1403 | fs->stack[num].idx = str_idx; | |
1404 | fs->stack[num].node = dest_node; | |
1405 | fs->stack[num].regs = re_malloc (regmatch_t, nregs); | |
1406 | if (fs->stack[num].regs == NULL) | |
1407 | return REG_ESPACE; | |
1408 | memcpy (fs->stack[num].regs, regs, sizeof (regmatch_t) * nregs); | |
1409 | err = re_node_set_init_copy (&fs->stack[num].eps_via_nodes, eps_via_nodes); | |
1410 | return err; | |
1411 | } | |
1412 | ||
1413 | static Idx | |
1414 | internal_function | |
1415 | pop_fail_stack (struct re_fail_stack_t *fs, Idx *pidx, Idx nregs, | |
1416 | regmatch_t *regs, re_node_set *eps_via_nodes) | |
1417 | { | |
1418 | Idx num = --fs->num; | |
1419 | assert (REG_VALID_INDEX (num)); | |
1420 | *pidx = fs->stack[num].idx; | |
1421 | memcpy (regs, fs->stack[num].regs, sizeof (regmatch_t) * nregs); | |
1422 | re_node_set_free (eps_via_nodes); | |
1423 | re_free (fs->stack[num].regs); | |
1424 | *eps_via_nodes = fs->stack[num].eps_via_nodes; | |
1425 | return fs->stack[num].node; | |
1426 | } | |
1427 | ||
1428 | /* Set the positions where the subexpressions are starts/ends to registers | |
1429 | PMATCH. | |
1430 | Note: We assume that pmatch[0] is already set, and | |
1431 | pmatch[i].rm_so == pmatch[i].rm_eo == -1 for 0 < i < nmatch. */ | |
1432 | ||
1433 | static reg_errcode_t | |
1434 | internal_function __attribute_warn_unused_result__ | |
1435 | set_regs (const regex_t *preg, const re_match_context_t *mctx, size_t nmatch, | |
1436 | regmatch_t *pmatch, bool fl_backtrack) | |
1437 | { | |
1438 | const re_dfa_t *dfa = (const re_dfa_t *) preg->buffer; | |
1439 | Idx idx, cur_node; | |
1440 | re_node_set eps_via_nodes; | |
1441 | struct re_fail_stack_t *fs; | |
1442 | struct re_fail_stack_t fs_body = { 0, 2, NULL }; | |
1443 | regmatch_t *prev_idx_match; | |
1444 | bool prev_idx_match_malloced = false; | |
1445 | ||
1446 | #ifdef DEBUG | |
1447 | assert (nmatch > 1); | |
1448 | assert (mctx->state_log != NULL); | |
1449 | #endif | |
1450 | if (fl_backtrack) | |
1451 | { | |
1452 | fs = &fs_body; | |
1453 | fs->stack = re_malloc (struct re_fail_stack_ent_t, fs->alloc); | |
1454 | if (fs->stack == NULL) | |
1455 | return REG_ESPACE; | |
1456 | } | |
1457 | else | |
1458 | fs = NULL; | |
1459 | ||
1460 | cur_node = dfa->init_node; | |
1461 | re_node_set_init_empty (&eps_via_nodes); | |
1462 | ||
1463 | if (__libc_use_alloca (nmatch * sizeof (regmatch_t))) | |
1464 | prev_idx_match = (regmatch_t *) alloca (nmatch * sizeof (regmatch_t)); | |
1465 | else | |
1466 | { | |
1467 | prev_idx_match = re_malloc (regmatch_t, nmatch); | |
1468 | if (prev_idx_match == NULL) | |
1469 | { | |
1470 | free_fail_stack_return (fs); | |
1471 | return REG_ESPACE; | |
1472 | } | |
1473 | prev_idx_match_malloced = true; | |
1474 | } | |
1475 | memcpy (prev_idx_match, pmatch, sizeof (regmatch_t) * nmatch); | |
1476 | ||
1477 | for (idx = pmatch[0].rm_so; idx <= pmatch[0].rm_eo ;) | |
1478 | { | |
1479 | update_regs (dfa, pmatch, prev_idx_match, cur_node, idx, nmatch); | |
1480 | ||
1481 | if (idx == pmatch[0].rm_eo && cur_node == mctx->last_node) | |
1482 | { | |
1483 | Idx reg_idx; | |
1484 | if (fs) | |
1485 | { | |
1486 | for (reg_idx = 0; reg_idx < nmatch; ++reg_idx) | |
1487 | if (pmatch[reg_idx].rm_so > -1 && pmatch[reg_idx].rm_eo == -1) | |
1488 | break; | |
1489 | if (reg_idx == nmatch) | |
1490 | { | |
1491 | re_node_set_free (&eps_via_nodes); | |
1492 | if (prev_idx_match_malloced) | |
1493 | re_free (prev_idx_match); | |
1494 | return free_fail_stack_return (fs); | |
1495 | } | |
1496 | cur_node = pop_fail_stack (fs, &idx, nmatch, pmatch, | |
1497 | &eps_via_nodes); | |
1498 | } | |
1499 | else | |
1500 | { | |
1501 | re_node_set_free (&eps_via_nodes); | |
1502 | if (prev_idx_match_malloced) | |
1503 | re_free (prev_idx_match); | |
1504 | return REG_NOERROR; | |
1505 | } | |
1506 | } | |
1507 | ||
1508 | /* Proceed to next node. */ | |
1509 | cur_node = proceed_next_node (mctx, nmatch, pmatch, &idx, cur_node, | |
1510 | &eps_via_nodes, fs); | |
1511 | ||
1512 | if (BE (! REG_VALID_INDEX (cur_node), 0)) | |
1513 | { | |
1514 | if (BE (cur_node == REG_ERROR, 0)) | |
1515 | { | |
1516 | re_node_set_free (&eps_via_nodes); | |
1517 | if (prev_idx_match_malloced) | |
1518 | re_free (prev_idx_match); | |
1519 | free_fail_stack_return (fs); | |
1520 | return REG_ESPACE; | |
1521 | } | |
1522 | if (fs) | |
1523 | cur_node = pop_fail_stack (fs, &idx, nmatch, pmatch, | |
1524 | &eps_via_nodes); | |
1525 | else | |
1526 | { | |
1527 | re_node_set_free (&eps_via_nodes); | |
1528 | if (prev_idx_match_malloced) | |
1529 | re_free (prev_idx_match); | |
1530 | return REG_NOMATCH; | |
1531 | } | |
1532 | } | |
1533 | } | |
1534 | re_node_set_free (&eps_via_nodes); | |
1535 | if (prev_idx_match_malloced) | |
1536 | re_free (prev_idx_match); | |
1537 | return free_fail_stack_return (fs); | |
1538 | } | |
1539 | ||
1540 | static reg_errcode_t | |
1541 | internal_function | |
1542 | free_fail_stack_return (struct re_fail_stack_t *fs) | |
1543 | { | |
1544 | if (fs) | |
1545 | { | |
1546 | Idx fs_idx; | |
1547 | for (fs_idx = 0; fs_idx < fs->num; ++fs_idx) | |
1548 | { | |
1549 | re_node_set_free (&fs->stack[fs_idx].eps_via_nodes); | |
1550 | re_free (fs->stack[fs_idx].regs); | |
1551 | } | |
1552 | re_free (fs->stack); | |
1553 | } | |
1554 | return REG_NOERROR; | |
1555 | } | |
1556 | ||
1557 | static void | |
1558 | internal_function | |
1559 | update_regs (const re_dfa_t *dfa, regmatch_t *pmatch, | |
1560 | regmatch_t *prev_idx_match, Idx cur_node, Idx cur_idx, Idx nmatch) | |
1561 | { | |
1562 | int type = dfa->nodes[cur_node].type; | |
1563 | if (type == OP_OPEN_SUBEXP) | |
1564 | { | |
1565 | Idx reg_num = dfa->nodes[cur_node].opr.idx + 1; | |
1566 | ||
1567 | /* We are at the first node of this sub expression. */ | |
1568 | if (reg_num < nmatch) | |
1569 | { | |
1570 | pmatch[reg_num].rm_so = cur_idx; | |
1571 | pmatch[reg_num].rm_eo = -1; | |
1572 | } | |
1573 | } | |
1574 | else if (type == OP_CLOSE_SUBEXP) | |
1575 | { | |
1576 | Idx reg_num = dfa->nodes[cur_node].opr.idx + 1; | |
1577 | if (reg_num < nmatch) | |
1578 | { | |
1579 | /* We are at the last node of this sub expression. */ | |
1580 | if (pmatch[reg_num].rm_so < cur_idx) | |
1581 | { | |
1582 | pmatch[reg_num].rm_eo = cur_idx; | |
1583 | /* This is a non-empty match or we are not inside an optional | |
1584 | subexpression. Accept this right away. */ | |
1585 | memcpy (prev_idx_match, pmatch, sizeof (regmatch_t) * nmatch); | |
1586 | } | |
1587 | else | |
1588 | { | |
1589 | if (dfa->nodes[cur_node].opt_subexp | |
1590 | && prev_idx_match[reg_num].rm_so != -1) | |
1591 | /* We transited through an empty match for an optional | |
1592 | subexpression, like (a?)*, and this is not the subexp's | |
1593 | first match. Copy back the old content of the registers | |
1594 | so that matches of an inner subexpression are undone as | |
1595 | well, like in ((a?))*. */ | |
1596 | memcpy (pmatch, prev_idx_match, sizeof (regmatch_t) * nmatch); | |
1597 | else | |
1598 | /* We completed a subexpression, but it may be part of | |
1599 | an optional one, so do not update PREV_IDX_MATCH. */ | |
1600 | pmatch[reg_num].rm_eo = cur_idx; | |
1601 | } | |
1602 | } | |
1603 | } | |
1604 | } | |
1605 | ||
1606 | /* This function checks the STATE_LOG from the SCTX->last_str_idx to 0 | |
1607 | and sift the nodes in each states according to the following rules. | |
1608 | Updated state_log will be wrote to STATE_LOG. | |
1609 | ||
1610 | Rules: We throw away the Node 'a' in the STATE_LOG[STR_IDX] if... | |
1611 | 1. When STR_IDX == MATCH_LAST(the last index in the state_log): | |
1612 | If 'a' isn't the LAST_NODE and 'a' can't epsilon transit to | |
1613 | the LAST_NODE, we throw away the node 'a'. | |
1614 | 2. When 0 <= STR_IDX < MATCH_LAST and 'a' accepts | |
1615 | string 's' and transit to 'b': | |
1616 | i. If 'b' isn't in the STATE_LOG[STR_IDX+strlen('s')], we throw | |
1617 | away the node 'a'. | |
1618 | ii. If 'b' is in the STATE_LOG[STR_IDX+strlen('s')] but 'b' is | |
1619 | thrown away, we throw away the node 'a'. | |
1620 | 3. When 0 <= STR_IDX < MATCH_LAST and 'a' epsilon transit to 'b': | |
1621 | i. If 'b' isn't in the STATE_LOG[STR_IDX], we throw away the | |
1622 | node 'a'. | |
1623 | ii. If 'b' is in the STATE_LOG[STR_IDX] but 'b' is thrown away, | |
1624 | we throw away the node 'a'. */ | |
1625 | ||
1626 | #define STATE_NODE_CONTAINS(state,node) \ | |
1627 | ((state) != NULL && re_node_set_contains (&(state)->nodes, node)) | |
1628 | ||
1629 | static reg_errcode_t | |
1630 | internal_function | |
1631 | sift_states_backward (const re_match_context_t *mctx, re_sift_context_t *sctx) | |
1632 | { | |
1633 | reg_errcode_t err; | |
1634 | int null_cnt = 0; | |
1635 | Idx str_idx = sctx->last_str_idx; | |
1636 | re_node_set cur_dest; | |
1637 | ||
1638 | #ifdef DEBUG | |
1639 | assert (mctx->state_log != NULL && mctx->state_log[str_idx] != NULL); | |
1640 | #endif | |
1641 | ||
1642 | /* Build sifted state_log[str_idx]. It has the nodes which can epsilon | |
1643 | transit to the last_node and the last_node itself. */ | |
1644 | err = re_node_set_init_1 (&cur_dest, sctx->last_node); | |
1645 | if (BE (err != REG_NOERROR, 0)) | |
1646 | return err; | |
1647 | err = update_cur_sifted_state (mctx, sctx, str_idx, &cur_dest); | |
1648 | if (BE (err != REG_NOERROR, 0)) | |
1649 | goto free_return; | |
1650 | ||
1651 | /* Then check each states in the state_log. */ | |
1652 | while (str_idx > 0) | |
1653 | { | |
1654 | /* Update counters. */ | |
1655 | null_cnt = (sctx->sifted_states[str_idx] == NULL) ? null_cnt + 1 : 0; | |
1656 | if (null_cnt > mctx->max_mb_elem_len) | |
1657 | { | |
1658 | memset (sctx->sifted_states, '\0', | |
1659 | sizeof (re_dfastate_t *) * str_idx); | |
1660 | re_node_set_free (&cur_dest); | |
1661 | return REG_NOERROR; | |
1662 | } | |
1663 | re_node_set_empty (&cur_dest); | |
1664 | --str_idx; | |
1665 | ||
1666 | if (mctx->state_log[str_idx]) | |
1667 | { | |
1668 | err = build_sifted_states (mctx, sctx, str_idx, &cur_dest); | |
1669 | if (BE (err != REG_NOERROR, 0)) | |
1670 | goto free_return; | |
1671 | } | |
1672 | ||
1673 | /* Add all the nodes which satisfy the following conditions: | |
1674 | - It can epsilon transit to a node in CUR_DEST. | |
1675 | - It is in CUR_SRC. | |
1676 | And update state_log. */ | |
1677 | err = update_cur_sifted_state (mctx, sctx, str_idx, &cur_dest); | |
1678 | if (BE (err != REG_NOERROR, 0)) | |
1679 | goto free_return; | |
1680 | } | |
1681 | err = REG_NOERROR; | |
1682 | free_return: | |
1683 | re_node_set_free (&cur_dest); | |
1684 | return err; | |
1685 | } | |
1686 | ||
1687 | static reg_errcode_t | |
1688 | internal_function __attribute_warn_unused_result__ | |
1689 | build_sifted_states (const re_match_context_t *mctx, re_sift_context_t *sctx, | |
1690 | Idx str_idx, re_node_set *cur_dest) | |
1691 | { | |
1692 | const re_dfa_t *const dfa = mctx->dfa; | |
1693 | const re_node_set *cur_src = &mctx->state_log[str_idx]->non_eps_nodes; | |
1694 | Idx i; | |
1695 | ||
1696 | /* Then build the next sifted state. | |
1697 | We build the next sifted state on 'cur_dest', and update | |
1698 | 'sifted_states[str_idx]' with 'cur_dest'. | |
1699 | Note: | |
1700 | 'cur_dest' is the sifted state from 'state_log[str_idx + 1]'. | |
1701 | 'cur_src' points the node_set of the old 'state_log[str_idx]' | |
1702 | (with the epsilon nodes pre-filtered out). */ | |
1703 | for (i = 0; i < cur_src->nelem; i++) | |
1704 | { | |
1705 | Idx prev_node = cur_src->elems[i]; | |
1706 | int naccepted = 0; | |
1707 | bool ok; | |
1708 | ||
1709 | #ifdef DEBUG | |
1710 | re_token_type_t type = dfa->nodes[prev_node].type; | |
1711 | assert (!IS_EPSILON_NODE (type)); | |
1712 | #endif | |
1713 | #ifdef RE_ENABLE_I18N | |
1714 | /* If the node may accept "multi byte". */ | |
1715 | if (dfa->nodes[prev_node].accept_mb) | |
1716 | naccepted = sift_states_iter_mb (mctx, sctx, prev_node, | |
1717 | str_idx, sctx->last_str_idx); | |
1718 | #endif /* RE_ENABLE_I18N */ | |
1719 | ||
1720 | /* We don't check backreferences here. | |
1721 | See update_cur_sifted_state(). */ | |
1722 | if (!naccepted | |
1723 | && check_node_accept (mctx, dfa->nodes + prev_node, str_idx) | |
1724 | && STATE_NODE_CONTAINS (sctx->sifted_states[str_idx + 1], | |
1725 | dfa->nexts[prev_node])) | |
1726 | naccepted = 1; | |
1727 | ||
1728 | if (naccepted == 0) | |
1729 | continue; | |
1730 | ||
1731 | if (sctx->limits.nelem) | |
1732 | { | |
1733 | Idx to_idx = str_idx + naccepted; | |
1734 | if (check_dst_limits (mctx, &sctx->limits, | |
1735 | dfa->nexts[prev_node], to_idx, | |
1736 | prev_node, str_idx)) | |
1737 | continue; | |
1738 | } | |
1739 | ok = re_node_set_insert (cur_dest, prev_node); | |
1740 | if (BE (! ok, 0)) | |
1741 | return REG_ESPACE; | |
1742 | } | |
1743 | ||
1744 | return REG_NOERROR; | |
1745 | } | |
1746 | ||
1747 | /* Helper functions. */ | |
1748 | ||
1749 | static reg_errcode_t | |
1750 | internal_function | |
1751 | clean_state_log_if_needed (re_match_context_t *mctx, Idx next_state_log_idx) | |
1752 | { | |
1753 | Idx top = mctx->state_log_top; | |
1754 | ||
1755 | if (next_state_log_idx >= mctx->input.bufs_len | |
1756 | || (next_state_log_idx >= mctx->input.valid_len | |
1757 | && mctx->input.valid_len < mctx->input.len)) | |
1758 | { | |
1759 | reg_errcode_t err; | |
1760 | err = extend_buffers (mctx); | |
1761 | if (BE (err != REG_NOERROR, 0)) | |
1762 | return err; | |
1763 | } | |
1764 | ||
1765 | if (top < next_state_log_idx) | |
1766 | { | |
1767 | memset (mctx->state_log + top + 1, '\0', | |
1768 | sizeof (re_dfastate_t *) * (next_state_log_idx - top)); | |
1769 | mctx->state_log_top = next_state_log_idx; | |
1770 | } | |
1771 | return REG_NOERROR; | |
1772 | } | |
1773 | ||
1774 | static reg_errcode_t | |
1775 | internal_function | |
1776 | merge_state_array (const re_dfa_t *dfa, re_dfastate_t **dst, | |
1777 | re_dfastate_t **src, Idx num) | |
1778 | { | |
1779 | Idx st_idx; | |
1780 | reg_errcode_t err; | |
1781 | for (st_idx = 0; st_idx < num; ++st_idx) | |
1782 | { | |
1783 | if (dst[st_idx] == NULL) | |
1784 | dst[st_idx] = src[st_idx]; | |
1785 | else if (src[st_idx] != NULL) | |
1786 | { | |
1787 | re_node_set merged_set; | |
1788 | err = re_node_set_init_union (&merged_set, &dst[st_idx]->nodes, | |
1789 | &src[st_idx]->nodes); | |
1790 | if (BE (err != REG_NOERROR, 0)) | |
1791 | return err; | |
1792 | dst[st_idx] = re_acquire_state (&err, dfa, &merged_set); | |
1793 | re_node_set_free (&merged_set); | |
1794 | if (BE (err != REG_NOERROR, 0)) | |
1795 | return err; | |
1796 | } | |
1797 | } | |
1798 | return REG_NOERROR; | |
1799 | } | |
1800 | ||
1801 | static reg_errcode_t | |
1802 | internal_function | |
1803 | update_cur_sifted_state (const re_match_context_t *mctx, | |
1804 | re_sift_context_t *sctx, Idx str_idx, | |
1805 | re_node_set *dest_nodes) | |
1806 | { | |
1807 | const re_dfa_t *const dfa = mctx->dfa; | |
1808 | reg_errcode_t err = REG_NOERROR; | |
1809 | const re_node_set *candidates; | |
1810 | candidates = ((mctx->state_log[str_idx] == NULL) ? NULL | |
1811 | : &mctx->state_log[str_idx]->nodes); | |
1812 | ||
1813 | if (dest_nodes->nelem == 0) | |
1814 | sctx->sifted_states[str_idx] = NULL; | |
1815 | else | |
1816 | { | |
1817 | if (candidates) | |
1818 | { | |
1819 | /* At first, add the nodes which can epsilon transit to a node in | |
1820 | DEST_NODE. */ | |
1821 | err = add_epsilon_src_nodes (dfa, dest_nodes, candidates); | |
1822 | if (BE (err != REG_NOERROR, 0)) | |
1823 | return err; | |
1824 | ||
1825 | /* Then, check the limitations in the current sift_context. */ | |
1826 | if (sctx->limits.nelem) | |
1827 | { | |
1828 | err = check_subexp_limits (dfa, dest_nodes, candidates, &sctx->limits, | |
1829 | mctx->bkref_ents, str_idx); | |
1830 | if (BE (err != REG_NOERROR, 0)) | |
1831 | return err; | |
1832 | } | |
1833 | } | |
1834 | ||
1835 | sctx->sifted_states[str_idx] = re_acquire_state (&err, dfa, dest_nodes); | |
1836 | if (BE (err != REG_NOERROR, 0)) | |
1837 | return err; | |
1838 | } | |
1839 | ||
1840 | if (candidates && mctx->state_log[str_idx]->has_backref) | |
1841 | { | |
1842 | err = sift_states_bkref (mctx, sctx, str_idx, candidates); | |
1843 | if (BE (err != REG_NOERROR, 0)) | |
1844 | return err; | |
1845 | } | |
1846 | return REG_NOERROR; | |
1847 | } | |
1848 | ||
1849 | static reg_errcode_t | |
1850 | internal_function __attribute_warn_unused_result__ | |
1851 | add_epsilon_src_nodes (const re_dfa_t *dfa, re_node_set *dest_nodes, | |
1852 | const re_node_set *candidates) | |
1853 | { | |
1854 | reg_errcode_t err = REG_NOERROR; | |
1855 | Idx i; | |
1856 | ||
1857 | re_dfastate_t *state = re_acquire_state (&err, dfa, dest_nodes); | |
1858 | if (BE (err != REG_NOERROR, 0)) | |
1859 | return err; | |
1860 | ||
1861 | if (!state->inveclosure.alloc) | |
1862 | { | |
1863 | err = re_node_set_alloc (&state->inveclosure, dest_nodes->nelem); | |
1864 | if (BE (err != REG_NOERROR, 0)) | |
1865 | return REG_ESPACE; | |
1866 | for (i = 0; i < dest_nodes->nelem; i++) | |
1867 | { | |
1868 | err = re_node_set_merge (&state->inveclosure, | |
1869 | dfa->inveclosures + dest_nodes->elems[i]); | |
1870 | if (BE (err != REG_NOERROR, 0)) | |
1871 | return REG_ESPACE; | |
1872 | } | |
1873 | } | |
1874 | return re_node_set_add_intersect (dest_nodes, candidates, | |
1875 | &state->inveclosure); | |
1876 | } | |
1877 | ||
1878 | static reg_errcode_t | |
1879 | internal_function | |
1880 | sub_epsilon_src_nodes (const re_dfa_t *dfa, Idx node, re_node_set *dest_nodes, | |
1881 | const re_node_set *candidates) | |
1882 | { | |
1883 | Idx ecl_idx; | |
1884 | reg_errcode_t err; | |
1885 | re_node_set *inv_eclosure = dfa->inveclosures + node; | |
1886 | re_node_set except_nodes; | |
1887 | re_node_set_init_empty (&except_nodes); | |
1888 | for (ecl_idx = 0; ecl_idx < inv_eclosure->nelem; ++ecl_idx) | |
1889 | { | |
1890 | Idx cur_node = inv_eclosure->elems[ecl_idx]; | |
1891 | if (cur_node == node) | |
1892 | continue; | |
1893 | if (IS_EPSILON_NODE (dfa->nodes[cur_node].type)) | |
1894 | { | |
1895 | Idx edst1 = dfa->edests[cur_node].elems[0]; | |
1896 | Idx edst2 = ((dfa->edests[cur_node].nelem > 1) | |
1897 | ? dfa->edests[cur_node].elems[1] : REG_MISSING); | |
1898 | if ((!re_node_set_contains (inv_eclosure, edst1) | |
1899 | && re_node_set_contains (dest_nodes, edst1)) | |
1900 | || (REG_VALID_NONZERO_INDEX (edst2) | |
1901 | && !re_node_set_contains (inv_eclosure, edst2) | |
1902 | && re_node_set_contains (dest_nodes, edst2))) | |
1903 | { | |
1904 | err = re_node_set_add_intersect (&except_nodes, candidates, | |
1905 | dfa->inveclosures + cur_node); | |
1906 | if (BE (err != REG_NOERROR, 0)) | |
1907 | { | |
1908 | re_node_set_free (&except_nodes); | |
1909 | return err; | |
1910 | } | |
1911 | } | |
1912 | } | |
1913 | } | |
1914 | for (ecl_idx = 0; ecl_idx < inv_eclosure->nelem; ++ecl_idx) | |
1915 | { | |
1916 | Idx cur_node = inv_eclosure->elems[ecl_idx]; | |
1917 | if (!re_node_set_contains (&except_nodes, cur_node)) | |
1918 | { | |
1919 | Idx idx = re_node_set_contains (dest_nodes, cur_node) - 1; | |
1920 | re_node_set_remove_at (dest_nodes, idx); | |
1921 | } | |
1922 | } | |
1923 | re_node_set_free (&except_nodes); | |
1924 | return REG_NOERROR; | |
1925 | } | |
1926 | ||
1927 | static bool | |
1928 | internal_function | |
1929 | check_dst_limits (const re_match_context_t *mctx, const re_node_set *limits, | |
1930 | Idx dst_node, Idx dst_idx, Idx src_node, Idx src_idx) | |
1931 | { | |
1932 | const re_dfa_t *const dfa = mctx->dfa; | |
1933 | Idx lim_idx, src_pos, dst_pos; | |
1934 | ||
1935 | Idx dst_bkref_idx = search_cur_bkref_entry (mctx, dst_idx); | |
1936 | Idx src_bkref_idx = search_cur_bkref_entry (mctx, src_idx); | |
1937 | for (lim_idx = 0; lim_idx < limits->nelem; ++lim_idx) | |
1938 | { | |
1939 | Idx subexp_idx; | |
1940 | struct re_backref_cache_entry *ent; | |
1941 | ent = mctx->bkref_ents + limits->elems[lim_idx]; | |
1942 | subexp_idx = dfa->nodes[ent->node].opr.idx; | |
1943 | ||
1944 | dst_pos = check_dst_limits_calc_pos (mctx, limits->elems[lim_idx], | |
1945 | subexp_idx, dst_node, dst_idx, | |
1946 | dst_bkref_idx); | |
1947 | src_pos = check_dst_limits_calc_pos (mctx, limits->elems[lim_idx], | |
1948 | subexp_idx, src_node, src_idx, | |
1949 | src_bkref_idx); | |
1950 | ||
1951 | /* In case of: | |
1952 | <src> <dst> ( <subexp> ) | |
1953 | ( <subexp> ) <src> <dst> | |
1954 | ( <subexp1> <src> <subexp2> <dst> <subexp3> ) */ | |
1955 | if (src_pos == dst_pos) | |
1956 | continue; /* This is unrelated limitation. */ | |
1957 | else | |
1958 | return true; | |
1959 | } | |
1960 | return false; | |
1961 | } | |
1962 | ||
1963 | static int | |
1964 | internal_function | |
1965 | check_dst_limits_calc_pos_1 (const re_match_context_t *mctx, int boundaries, | |
1966 | Idx subexp_idx, Idx from_node, Idx bkref_idx) | |
1967 | { | |
1968 | const re_dfa_t *const dfa = mctx->dfa; | |
1969 | const re_node_set *eclosures = dfa->eclosures + from_node; | |
1970 | Idx node_idx; | |
1971 | ||
1972 | /* Else, we are on the boundary: examine the nodes on the epsilon | |
1973 | closure. */ | |
1974 | for (node_idx = 0; node_idx < eclosures->nelem; ++node_idx) | |
1975 | { | |
1976 | Idx node = eclosures->elems[node_idx]; | |
1977 | switch (dfa->nodes[node].type) | |
1978 | { | |
1979 | case OP_BACK_REF: | |
1980 | if (bkref_idx != REG_MISSING) | |
1981 | { | |
1982 | struct re_backref_cache_entry *ent = mctx->bkref_ents + bkref_idx; | |
1983 | do | |
1984 | { | |
1985 | Idx dst; | |
1986 | int cpos; | |
1987 | ||
1988 | if (ent->node != node) | |
1989 | continue; | |
1990 | ||
1991 | if (subexp_idx < BITSET_WORD_BITS | |
1992 | && !(ent->eps_reachable_subexps_map | |
1993 | & ((bitset_word_t) 1 << subexp_idx))) | |
1994 | continue; | |
1995 | ||
1996 | /* Recurse trying to reach the OP_OPEN_SUBEXP and | |
1997 | OP_CLOSE_SUBEXP cases below. But, if the | |
1998 | destination node is the same node as the source | |
1999 | node, don't recurse because it would cause an | |
2000 | infinite loop: a regex that exhibits this behavior | |
2001 | is ()\1*\1* */ | |
2002 | dst = dfa->edests[node].elems[0]; | |
2003 | if (dst == from_node) | |
2004 | { | |
2005 | if (boundaries & 1) | |
2006 | return -1; | |
2007 | else /* if (boundaries & 2) */ | |
2008 | return 0; | |
2009 | } | |
2010 | ||
2011 | cpos = | |
2012 | check_dst_limits_calc_pos_1 (mctx, boundaries, subexp_idx, | |
2013 | dst, bkref_idx); | |
2014 | if (cpos == -1 /* && (boundaries & 1) */) | |
2015 | return -1; | |
2016 | if (cpos == 0 && (boundaries & 2)) | |
2017 | return 0; | |
2018 | ||
2019 | if (subexp_idx < BITSET_WORD_BITS) | |
2020 | ent->eps_reachable_subexps_map | |
2021 | &= ~((bitset_word_t) 1 << subexp_idx); | |
2022 | } | |
2023 | while (ent++->more); | |
2024 | } | |
2025 | break; | |
2026 | ||
2027 | case OP_OPEN_SUBEXP: | |
2028 | if ((boundaries & 1) && subexp_idx == dfa->nodes[node].opr.idx) | |
2029 | return -1; | |
2030 | break; | |
2031 | ||
2032 | case OP_CLOSE_SUBEXP: | |
2033 | if ((boundaries & 2) && subexp_idx == dfa->nodes[node].opr.idx) | |
2034 | return 0; | |
2035 | break; | |
2036 | ||
2037 | default: | |
2038 | break; | |
2039 | } | |
2040 | } | |
2041 | ||
2042 | return (boundaries & 2) ? 1 : 0; | |
2043 | } | |
2044 | ||
2045 | static int | |
2046 | internal_function | |
2047 | check_dst_limits_calc_pos (const re_match_context_t *mctx, Idx limit, | |
2048 | Idx subexp_idx, Idx from_node, Idx str_idx, | |
2049 | Idx bkref_idx) | |
2050 | { | |
2051 | struct re_backref_cache_entry *lim = mctx->bkref_ents + limit; | |
2052 | int boundaries; | |
2053 | ||
2054 | /* If we are outside the range of the subexpression, return -1 or 1. */ | |
2055 | if (str_idx < lim->subexp_from) | |
2056 | return -1; | |
2057 | ||
2058 | if (lim->subexp_to < str_idx) | |
2059 | return 1; | |
2060 | ||
2061 | /* If we are within the subexpression, return 0. */ | |
2062 | boundaries = (str_idx == lim->subexp_from); | |
2063 | boundaries |= (str_idx == lim->subexp_to) << 1; | |
2064 | if (boundaries == 0) | |
2065 | return 0; | |
2066 | ||
2067 | /* Else, examine epsilon closure. */ | |
2068 | return check_dst_limits_calc_pos_1 (mctx, boundaries, subexp_idx, | |
2069 | from_node, bkref_idx); | |
2070 | } | |
2071 | ||
2072 | /* Check the limitations of sub expressions LIMITS, and remove the nodes | |
2073 | which are against limitations from DEST_NODES. */ | |
2074 | ||
2075 | static reg_errcode_t | |
2076 | internal_function | |
2077 | check_subexp_limits (const re_dfa_t *dfa, re_node_set *dest_nodes, | |
2078 | const re_node_set *candidates, re_node_set *limits, | |
2079 | struct re_backref_cache_entry *bkref_ents, Idx str_idx) | |
2080 | { | |
2081 | reg_errcode_t err; | |
2082 | Idx node_idx, lim_idx; | |
2083 | ||
2084 | for (lim_idx = 0; lim_idx < limits->nelem; ++lim_idx) | |
2085 | { | |
2086 | Idx subexp_idx; | |
2087 | struct re_backref_cache_entry *ent; | |
2088 | ent = bkref_ents + limits->elems[lim_idx]; | |
2089 | ||
2090 | if (str_idx <= ent->subexp_from || ent->str_idx < str_idx) | |
2091 | continue; /* This is unrelated limitation. */ | |
2092 | ||
2093 | subexp_idx = dfa->nodes[ent->node].opr.idx; | |
2094 | if (ent->subexp_to == str_idx) | |
2095 | { | |
2096 | Idx ops_node = REG_MISSING; | |
2097 | Idx cls_node = REG_MISSING; | |
2098 | for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx) | |
2099 | { | |
2100 | Idx node = dest_nodes->elems[node_idx]; | |
2101 | re_token_type_t type = dfa->nodes[node].type; | |
2102 | if (type == OP_OPEN_SUBEXP | |
2103 | && subexp_idx == dfa->nodes[node].opr.idx) | |
2104 | ops_node = node; | |
2105 | else if (type == OP_CLOSE_SUBEXP | |
2106 | && subexp_idx == dfa->nodes[node].opr.idx) | |
2107 | cls_node = node; | |
2108 | } | |
2109 | ||
2110 | /* Check the limitation of the open subexpression. */ | |
2111 | /* Note that (ent->subexp_to = str_idx != ent->subexp_from). */ | |
2112 | if (REG_VALID_INDEX (ops_node)) | |
2113 | { | |
2114 | err = sub_epsilon_src_nodes (dfa, ops_node, dest_nodes, | |
2115 | candidates); | |
2116 | if (BE (err != REG_NOERROR, 0)) | |
2117 | return err; | |
2118 | } | |
2119 | ||
2120 | /* Check the limitation of the close subexpression. */ | |
2121 | if (REG_VALID_INDEX (cls_node)) | |
2122 | for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx) | |
2123 | { | |
2124 | Idx node = dest_nodes->elems[node_idx]; | |
2125 | if (!re_node_set_contains (dfa->inveclosures + node, | |
2126 | cls_node) | |
2127 | && !re_node_set_contains (dfa->eclosures + node, | |
2128 | cls_node)) | |
2129 | { | |
2130 | /* It is against this limitation. | |
2131 | Remove it form the current sifted state. */ | |
2132 | err = sub_epsilon_src_nodes (dfa, node, dest_nodes, | |
2133 | candidates); | |
2134 | if (BE (err != REG_NOERROR, 0)) | |
2135 | return err; | |
2136 | --node_idx; | |
2137 | } | |
2138 | } | |
2139 | } | |
2140 | else /* (ent->subexp_to != str_idx) */ | |
2141 | { | |
2142 | for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx) | |
2143 | { | |
2144 | Idx node = dest_nodes->elems[node_idx]; | |
2145 | re_token_type_t type = dfa->nodes[node].type; | |
2146 | if (type == OP_CLOSE_SUBEXP || type == OP_OPEN_SUBEXP) | |
2147 | { | |
2148 | if (subexp_idx != dfa->nodes[node].opr.idx) | |
2149 | continue; | |
2150 | /* It is against this limitation. | |
2151 | Remove it form the current sifted state. */ | |
2152 | err = sub_epsilon_src_nodes (dfa, node, dest_nodes, | |
2153 | candidates); | |
2154 | if (BE (err != REG_NOERROR, 0)) | |
2155 | return err; | |
2156 | } | |
2157 | } | |
2158 | } | |
2159 | } | |
2160 | return REG_NOERROR; | |
2161 | } | |
2162 | ||
2163 | static reg_errcode_t | |
2164 | internal_function __attribute_warn_unused_result__ | |
2165 | sift_states_bkref (const re_match_context_t *mctx, re_sift_context_t *sctx, | |
2166 | Idx str_idx, const re_node_set *candidates) | |
2167 | { | |
2168 | const re_dfa_t *const dfa = mctx->dfa; | |
2169 | reg_errcode_t err; | |
2170 | Idx node_idx, node; | |
2171 | re_sift_context_t local_sctx; | |
2172 | Idx first_idx = search_cur_bkref_entry (mctx, str_idx); | |
2173 | ||
2174 | if (first_idx == REG_MISSING) | |
2175 | return REG_NOERROR; | |
2176 | ||
2177 | local_sctx.sifted_states = NULL; /* Mark that it hasn't been initialized. */ | |
2178 | ||
2179 | for (node_idx = 0; node_idx < candidates->nelem; ++node_idx) | |
2180 | { | |
2181 | Idx enabled_idx; | |
2182 | re_token_type_t type; | |
2183 | struct re_backref_cache_entry *entry; | |
2184 | node = candidates->elems[node_idx]; | |
2185 | type = dfa->nodes[node].type; | |
2186 | /* Avoid infinite loop for the REs like "()\1+". */ | |
2187 | if (node == sctx->last_node && str_idx == sctx->last_str_idx) | |
2188 | continue; | |
2189 | if (type != OP_BACK_REF) | |
2190 | continue; | |
2191 | ||
2192 | entry = mctx->bkref_ents + first_idx; | |
2193 | enabled_idx = first_idx; | |
2194 | do | |
2195 | { | |
2196 | Idx subexp_len; | |
2197 | Idx to_idx; | |
2198 | Idx dst_node; | |
2199 | bool ok; | |
2200 | re_dfastate_t *cur_state; | |
2201 | ||
2202 | if (entry->node != node) | |
2203 | continue; | |
2204 | subexp_len = entry->subexp_to - entry->subexp_from; | |
2205 | to_idx = str_idx + subexp_len; | |
2206 | dst_node = (subexp_len ? dfa->nexts[node] | |
2207 | : dfa->edests[node].elems[0]); | |
2208 | ||
2209 | if (to_idx > sctx->last_str_idx | |
2210 | || sctx->sifted_states[to_idx] == NULL | |
2211 | || !STATE_NODE_CONTAINS (sctx->sifted_states[to_idx], dst_node) | |
2212 | || check_dst_limits (mctx, &sctx->limits, node, | |
2213 | str_idx, dst_node, to_idx)) | |
2214 | continue; | |
2215 | ||
2216 | if (local_sctx.sifted_states == NULL) | |
2217 | { | |
2218 | local_sctx = *sctx; | |
2219 | err = re_node_set_init_copy (&local_sctx.limits, &sctx->limits); | |
2220 | if (BE (err != REG_NOERROR, 0)) | |
2221 | goto free_return; | |
2222 | } | |
2223 | local_sctx.last_node = node; | |
2224 | local_sctx.last_str_idx = str_idx; | |
2225 | ok = re_node_set_insert (&local_sctx.limits, enabled_idx); | |
2226 | if (BE (! ok, 0)) | |
2227 | { | |
2228 | err = REG_ESPACE; | |
2229 | goto free_return; | |
2230 | } | |
2231 | cur_state = local_sctx.sifted_states[str_idx]; | |
2232 | err = sift_states_backward (mctx, &local_sctx); | |
2233 | if (BE (err != REG_NOERROR, 0)) | |
2234 | goto free_return; | |
2235 | if (sctx->limited_states != NULL) | |
2236 | { | |
2237 | err = merge_state_array (dfa, sctx->limited_states, | |
2238 | local_sctx.sifted_states, | |
2239 | str_idx + 1); | |
2240 | if (BE (err != REG_NOERROR, 0)) | |
2241 | goto free_return; | |
2242 | } | |
2243 | local_sctx.sifted_states[str_idx] = cur_state; | |
2244 | re_node_set_remove (&local_sctx.limits, enabled_idx); | |
2245 | ||
2246 | /* mctx->bkref_ents may have changed, reload the pointer. */ | |
2247 | entry = mctx->bkref_ents + enabled_idx; | |
2248 | } | |
2249 | while (enabled_idx++, entry++->more); | |
2250 | } | |
2251 | err = REG_NOERROR; | |
2252 | free_return: | |
2253 | if (local_sctx.sifted_states != NULL) | |
2254 | { | |
2255 | re_node_set_free (&local_sctx.limits); | |
2256 | } | |
2257 | ||
2258 | return err; | |
2259 | } | |
2260 | ||
2261 | ||
2262 | #ifdef RE_ENABLE_I18N | |
2263 | static int | |
2264 | internal_function | |
2265 | sift_states_iter_mb (const re_match_context_t *mctx, re_sift_context_t *sctx, | |
2266 | Idx node_idx, Idx str_idx, Idx max_str_idx) | |
2267 | { | |
2268 | const re_dfa_t *const dfa = mctx->dfa; | |
2269 | int naccepted; | |
2270 | /* Check the node can accept "multi byte". */ | |
2271 | naccepted = check_node_accept_bytes (dfa, node_idx, &mctx->input, str_idx); | |
2272 | if (naccepted > 0 && str_idx + naccepted <= max_str_idx && | |
2273 | !STATE_NODE_CONTAINS (sctx->sifted_states[str_idx + naccepted], | |
2274 | dfa->nexts[node_idx])) | |
2275 | /* The node can't accept the "multi byte", or the | |
2276 | destination was already thrown away, then the node | |
2277 | could't accept the current input "multi byte". */ | |
2278 | naccepted = 0; | |
2279 | /* Otherwise, it is sure that the node could accept | |
2280 | 'naccepted' bytes input. */ | |
2281 | return naccepted; | |
2282 | } | |
2283 | #endif /* RE_ENABLE_I18N */ | |
2284 | ||
2285 | \f | |
2286 | /* Functions for state transition. */ | |
2287 | ||
2288 | /* Return the next state to which the current state STATE will transit by | |
2289 | accepting the current input byte, and update STATE_LOG if necessary. | |
2290 | If STATE can accept a multibyte char/collating element/back reference | |
2291 | update the destination of STATE_LOG. */ | |
2292 | ||
2293 | static re_dfastate_t * | |
2294 | internal_function __attribute_warn_unused_result__ | |
2295 | transit_state (reg_errcode_t *err, re_match_context_t *mctx, | |
2296 | re_dfastate_t *state) | |
2297 | { | |
2298 | re_dfastate_t **trtable; | |
2299 | unsigned char ch; | |
2300 | ||
2301 | #ifdef RE_ENABLE_I18N | |
2302 | /* If the current state can accept multibyte. */ | |
2303 | if (BE (state->accept_mb, 0)) | |
2304 | { | |
2305 | *err = transit_state_mb (mctx, state); | |
2306 | if (BE (*err != REG_NOERROR, 0)) | |
2307 | return NULL; | |
2308 | } | |
2309 | #endif /* RE_ENABLE_I18N */ | |
2310 | ||
2311 | /* Then decide the next state with the single byte. */ | |
2312 | #if 0 | |
2313 | if (0) | |
2314 | /* don't use transition table */ | |
2315 | return transit_state_sb (err, mctx, state); | |
2316 | #endif | |
2317 | ||
2318 | /* Use transition table */ | |
2319 | ch = re_string_fetch_byte (&mctx->input); | |
2320 | for (;;) | |
2321 | { | |
2322 | trtable = state->trtable; | |
2323 | if (BE (trtable != NULL, 1)) | |
2324 | return trtable[ch]; | |
2325 | ||
2326 | trtable = state->word_trtable; | |
2327 | if (BE (trtable != NULL, 1)) | |
2328 | { | |
2329 | unsigned int context; | |
2330 | context | |
2331 | = re_string_context_at (&mctx->input, | |
2332 | re_string_cur_idx (&mctx->input) - 1, | |
2333 | mctx->eflags); | |
2334 | if (IS_WORD_CONTEXT (context)) | |
2335 | return trtable[ch + SBC_MAX]; | |
2336 | else | |
2337 | return trtable[ch]; | |
2338 | } | |
2339 | ||
2340 | if (!build_trtable (mctx->dfa, state)) | |
2341 | { | |
2342 | *err = REG_ESPACE; | |
2343 | return NULL; | |
2344 | } | |
2345 | ||
2346 | /* Retry, we now have a transition table. */ | |
2347 | } | |
2348 | } | |
2349 | ||
2350 | /* Update the state_log if we need */ | |
2351 | static re_dfastate_t * | |
2352 | internal_function | |
2353 | merge_state_with_log (reg_errcode_t *err, re_match_context_t *mctx, | |
2354 | re_dfastate_t *next_state) | |
2355 | { | |
2356 | const re_dfa_t *const dfa = mctx->dfa; | |
2357 | Idx cur_idx = re_string_cur_idx (&mctx->input); | |
2358 | ||
2359 | if (cur_idx > mctx->state_log_top) | |
2360 | { | |
2361 | mctx->state_log[cur_idx] = next_state; | |
2362 | mctx->state_log_top = cur_idx; | |
2363 | } | |
2364 | else if (mctx->state_log[cur_idx] == 0) | |
2365 | { | |
2366 | mctx->state_log[cur_idx] = next_state; | |
2367 | } | |
2368 | else | |
2369 | { | |
2370 | re_dfastate_t *pstate; | |
2371 | unsigned int context; | |
2372 | re_node_set next_nodes, *log_nodes, *table_nodes = NULL; | |
2373 | /* If (state_log[cur_idx] != 0), it implies that cur_idx is | |
2374 | the destination of a multibyte char/collating element/ | |
2375 | back reference. Then the next state is the union set of | |
2376 | these destinations and the results of the transition table. */ | |
2377 | pstate = mctx->state_log[cur_idx]; | |
2378 | log_nodes = pstate->entrance_nodes; | |
2379 | if (next_state != NULL) | |
2380 | { | |
2381 | table_nodes = next_state->entrance_nodes; | |
2382 | *err = re_node_set_init_union (&next_nodes, table_nodes, | |
2383 | log_nodes); | |
2384 | if (BE (*err != REG_NOERROR, 0)) | |
2385 | return NULL; | |
2386 | } | |
2387 | else | |
2388 | next_nodes = *log_nodes; | |
2389 | /* Note: We already add the nodes of the initial state, | |
2390 | then we don't need to add them here. */ | |
2391 | ||
2392 | context = re_string_context_at (&mctx->input, | |
2393 | re_string_cur_idx (&mctx->input) - 1, | |
2394 | mctx->eflags); | |
2395 | next_state = mctx->state_log[cur_idx] | |
2396 | = re_acquire_state_context (err, dfa, &next_nodes, context); | |
2397 | /* We don't need to check errors here, since the return value of | |
2398 | this function is next_state and ERR is already set. */ | |
2399 | ||
2400 | if (table_nodes != NULL) | |
2401 | re_node_set_free (&next_nodes); | |
2402 | } | |
2403 | ||
2404 | if (BE (dfa->nbackref, 0) && next_state != NULL) | |
2405 | { | |
2406 | /* Check OP_OPEN_SUBEXP in the current state in case that we use them | |
2407 | later. We must check them here, since the back references in the | |
2408 | next state might use them. */ | |
2409 | *err = check_subexp_matching_top (mctx, &next_state->nodes, | |
2410 | cur_idx); | |
2411 | if (BE (*err != REG_NOERROR, 0)) | |
2412 | return NULL; | |
2413 | ||
2414 | /* If the next state has back references. */ | |
2415 | if (next_state->has_backref) | |
2416 | { | |
2417 | *err = transit_state_bkref (mctx, &next_state->nodes); | |
2418 | if (BE (*err != REG_NOERROR, 0)) | |
2419 | return NULL; | |
2420 | next_state = mctx->state_log[cur_idx]; | |
2421 | } | |
2422 | } | |
2423 | ||
2424 | return next_state; | |
2425 | } | |
2426 | ||
2427 | /* Skip bytes in the input that correspond to part of a | |
2428 | multi-byte match, then look in the log for a state | |
2429 | from which to restart matching. */ | |
2430 | static re_dfastate_t * | |
2431 | internal_function | |
2432 | find_recover_state (reg_errcode_t *err, re_match_context_t *mctx) | |
2433 | { | |
2434 | re_dfastate_t *cur_state; | |
2435 | do | |
2436 | { | |
2437 | Idx max = mctx->state_log_top; | |
2438 | Idx cur_str_idx = re_string_cur_idx (&mctx->input); | |
2439 | ||
2440 | do | |
2441 | { | |
2442 | if (++cur_str_idx > max) | |
2443 | return NULL; | |
2444 | re_string_skip_bytes (&mctx->input, 1); | |
2445 | } | |
2446 | while (mctx->state_log[cur_str_idx] == NULL); | |
2447 | ||
2448 | cur_state = merge_state_with_log (err, mctx, NULL); | |
2449 | } | |
2450 | while (*err == REG_NOERROR && cur_state == NULL); | |
2451 | return cur_state; | |
2452 | } | |
2453 | ||
2454 | /* Helper functions for transit_state. */ | |
2455 | ||
2456 | /* From the node set CUR_NODES, pick up the nodes whose types are | |
2457 | OP_OPEN_SUBEXP and which have corresponding back references in the regular | |
2458 | expression. And register them to use them later for evaluating the | |
2459 | correspoding back references. */ | |
2460 | ||
2461 | static reg_errcode_t | |
2462 | internal_function | |
2463 | check_subexp_matching_top (re_match_context_t *mctx, re_node_set *cur_nodes, | |
2464 | Idx str_idx) | |
2465 | { | |
2466 | const re_dfa_t *const dfa = mctx->dfa; | |
2467 | Idx node_idx; | |
2468 | reg_errcode_t err; | |
2469 | ||
2470 | /* TODO: This isn't efficient. | |
2471 | Because there might be more than one nodes whose types are | |
2472 | OP_OPEN_SUBEXP and whose index is SUBEXP_IDX, we must check all | |
2473 | nodes. | |
2474 | E.g. RE: (a){2} */ | |
2475 | for (node_idx = 0; node_idx < cur_nodes->nelem; ++node_idx) | |
2476 | { | |
2477 | Idx node = cur_nodes->elems[node_idx]; | |
2478 | if (dfa->nodes[node].type == OP_OPEN_SUBEXP | |
2479 | && dfa->nodes[node].opr.idx < BITSET_WORD_BITS | |
2480 | && (dfa->used_bkref_map | |
2481 | & ((bitset_word_t) 1 << dfa->nodes[node].opr.idx))) | |
2482 | { | |
2483 | err = match_ctx_add_subtop (mctx, node, str_idx); | |
2484 | if (BE (err != REG_NOERROR, 0)) | |
2485 | return err; | |
2486 | } | |
2487 | } | |
2488 | return REG_NOERROR; | |
2489 | } | |
2490 | ||
2491 | #if 0 | |
2492 | /* Return the next state to which the current state STATE will transit by | |
2493 | accepting the current input byte. */ | |
2494 | ||
2495 | static re_dfastate_t * | |
2496 | transit_state_sb (reg_errcode_t *err, re_match_context_t *mctx, | |
2497 | re_dfastate_t *state) | |
2498 | { | |
2499 | const re_dfa_t *const dfa = mctx->dfa; | |
2500 | re_node_set next_nodes; | |
2501 | re_dfastate_t *next_state; | |
2502 | Idx node_cnt, cur_str_idx = re_string_cur_idx (&mctx->input); | |
2503 | unsigned int context; | |
2504 | ||
2505 | *err = re_node_set_alloc (&next_nodes, state->nodes.nelem + 1); | |
2506 | if (BE (*err != REG_NOERROR, 0)) | |
2507 | return NULL; | |
2508 | for (node_cnt = 0; node_cnt < state->nodes.nelem; ++node_cnt) | |
2509 | { | |
2510 | Idx cur_node = state->nodes.elems[node_cnt]; | |
2511 | if (check_node_accept (mctx, dfa->nodes + cur_node, cur_str_idx)) | |
2512 | { | |
2513 | *err = re_node_set_merge (&next_nodes, | |
2514 | dfa->eclosures + dfa->nexts[cur_node]); | |
2515 | if (BE (*err != REG_NOERROR, 0)) | |
2516 | { | |
2517 | re_node_set_free (&next_nodes); | |
2518 | return NULL; | |
2519 | } | |
2520 | } | |
2521 | } | |
2522 | context = re_string_context_at (&mctx->input, cur_str_idx, mctx->eflags); | |
2523 | next_state = re_acquire_state_context (err, dfa, &next_nodes, context); | |
2524 | /* We don't need to check errors here, since the return value of | |
2525 | this function is next_state and ERR is already set. */ | |
2526 | ||
2527 | re_node_set_free (&next_nodes); | |
2528 | re_string_skip_bytes (&mctx->input, 1); | |
2529 | return next_state; | |
2530 | } | |
2531 | #endif | |
2532 | ||
2533 | #ifdef RE_ENABLE_I18N | |
2534 | static reg_errcode_t | |
2535 | internal_function | |
2536 | transit_state_mb (re_match_context_t *mctx, re_dfastate_t *pstate) | |
2537 | { | |
2538 | const re_dfa_t *const dfa = mctx->dfa; | |
2539 | reg_errcode_t err; | |
2540 | Idx i; | |
2541 | ||
2542 | for (i = 0; i < pstate->nodes.nelem; ++i) | |
2543 | { | |
2544 | re_node_set dest_nodes, *new_nodes; | |
2545 | Idx cur_node_idx = pstate->nodes.elems[i]; | |
2546 | int naccepted; | |
2547 | Idx dest_idx; | |
2548 | unsigned int context; | |
2549 | re_dfastate_t *dest_state; | |
2550 | ||
2551 | if (!dfa->nodes[cur_node_idx].accept_mb) | |
2552 | continue; | |
2553 | ||
2554 | if (dfa->nodes[cur_node_idx].constraint) | |
2555 | { | |
2556 | context = re_string_context_at (&mctx->input, | |
2557 | re_string_cur_idx (&mctx->input), | |
2558 | mctx->eflags); | |
2559 | if (NOT_SATISFY_NEXT_CONSTRAINT (dfa->nodes[cur_node_idx].constraint, | |
2560 | context)) | |
2561 | continue; | |
2562 | } | |
2563 | ||
2564 | /* How many bytes the node can accept? */ | |
2565 | naccepted = check_node_accept_bytes (dfa, cur_node_idx, &mctx->input, | |
2566 | re_string_cur_idx (&mctx->input)); | |
2567 | if (naccepted == 0) | |
2568 | continue; | |
2569 | ||
2570 | /* The node can accepts 'naccepted' bytes. */ | |
2571 | dest_idx = re_string_cur_idx (&mctx->input) + naccepted; | |
2572 | mctx->max_mb_elem_len = ((mctx->max_mb_elem_len < naccepted) ? naccepted | |
2573 | : mctx->max_mb_elem_len); | |
2574 | err = clean_state_log_if_needed (mctx, dest_idx); | |
2575 | if (BE (err != REG_NOERROR, 0)) | |
2576 | return err; | |
2577 | #ifdef DEBUG | |
2578 | assert (dfa->nexts[cur_node_idx] != REG_MISSING); | |
2579 | #endif | |
2580 | new_nodes = dfa->eclosures + dfa->nexts[cur_node_idx]; | |
2581 | ||
2582 | dest_state = mctx->state_log[dest_idx]; | |
2583 | if (dest_state == NULL) | |
2584 | dest_nodes = *new_nodes; | |
2585 | else | |
2586 | { | |
2587 | err = re_node_set_init_union (&dest_nodes, | |
2588 | dest_state->entrance_nodes, new_nodes); | |
2589 | if (BE (err != REG_NOERROR, 0)) | |
2590 | return err; | |
2591 | } | |
2592 | context = re_string_context_at (&mctx->input, dest_idx - 1, | |
2593 | mctx->eflags); | |
2594 | mctx->state_log[dest_idx] | |
2595 | = re_acquire_state_context (&err, dfa, &dest_nodes, context); | |
2596 | if (dest_state != NULL) | |
2597 | re_node_set_free (&dest_nodes); | |
2598 | if (BE (mctx->state_log[dest_idx] == NULL && err != REG_NOERROR, 0)) | |
2599 | return err; | |
2600 | } | |
2601 | return REG_NOERROR; | |
2602 | } | |
2603 | #endif /* RE_ENABLE_I18N */ | |
2604 | ||
2605 | static reg_errcode_t | |
2606 | internal_function | |
2607 | transit_state_bkref (re_match_context_t *mctx, const re_node_set *nodes) | |
2608 | { | |
2609 | const re_dfa_t *const dfa = mctx->dfa; | |
2610 | reg_errcode_t err; | |
2611 | Idx i; | |
2612 | Idx cur_str_idx = re_string_cur_idx (&mctx->input); | |
2613 | ||
2614 | for (i = 0; i < nodes->nelem; ++i) | |
2615 | { | |
2616 | Idx dest_str_idx, prev_nelem, bkc_idx; | |
2617 | Idx node_idx = nodes->elems[i]; | |
2618 | unsigned int context; | |
2619 | const re_token_t *node = dfa->nodes + node_idx; | |
2620 | re_node_set *new_dest_nodes; | |
2621 | ||
2622 | /* Check whether 'node' is a backreference or not. */ | |
2623 | if (node->type != OP_BACK_REF) | |
2624 | continue; | |
2625 | ||
2626 | if (node->constraint) | |
2627 | { | |
2628 | context = re_string_context_at (&mctx->input, cur_str_idx, | |
2629 | mctx->eflags); | |
2630 | if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context)) | |
2631 | continue; | |
2632 | } | |
2633 | ||
2634 | /* 'node' is a backreference. | |
2635 | Check the substring which the substring matched. */ | |
2636 | bkc_idx = mctx->nbkref_ents; | |
2637 | err = get_subexp (mctx, node_idx, cur_str_idx); | |
2638 | if (BE (err != REG_NOERROR, 0)) | |
2639 | goto free_return; | |
2640 | ||
2641 | /* And add the epsilon closures (which is 'new_dest_nodes') of | |
2642 | the backreference to appropriate state_log. */ | |
2643 | #ifdef DEBUG | |
2644 | assert (dfa->nexts[node_idx] != REG_MISSING); | |
2645 | #endif | |
2646 | for (; bkc_idx < mctx->nbkref_ents; ++bkc_idx) | |
2647 | { | |
2648 | Idx subexp_len; | |
2649 | re_dfastate_t *dest_state; | |
2650 | struct re_backref_cache_entry *bkref_ent; | |
2651 | bkref_ent = mctx->bkref_ents + bkc_idx; | |
2652 | if (bkref_ent->node != node_idx || bkref_ent->str_idx != cur_str_idx) | |
2653 | continue; | |
2654 | subexp_len = bkref_ent->subexp_to - bkref_ent->subexp_from; | |
2655 | new_dest_nodes = (subexp_len == 0 | |
2656 | ? dfa->eclosures + dfa->edests[node_idx].elems[0] | |
2657 | : dfa->eclosures + dfa->nexts[node_idx]); | |
2658 | dest_str_idx = (cur_str_idx + bkref_ent->subexp_to | |
2659 | - bkref_ent->subexp_from); | |
2660 | context = re_string_context_at (&mctx->input, dest_str_idx - 1, | |
2661 | mctx->eflags); | |
2662 | dest_state = mctx->state_log[dest_str_idx]; | |
2663 | prev_nelem = ((mctx->state_log[cur_str_idx] == NULL) ? 0 | |
2664 | : mctx->state_log[cur_str_idx]->nodes.nelem); | |
2665 | /* Add 'new_dest_node' to state_log. */ | |
2666 | if (dest_state == NULL) | |
2667 | { | |
2668 | mctx->state_log[dest_str_idx] | |
2669 | = re_acquire_state_context (&err, dfa, new_dest_nodes, | |
2670 | context); | |
2671 | if (BE (mctx->state_log[dest_str_idx] == NULL | |
2672 | && err != REG_NOERROR, 0)) | |
2673 | goto free_return; | |
2674 | } | |
2675 | else | |
2676 | { | |
2677 | re_node_set dest_nodes; | |
2678 | err = re_node_set_init_union (&dest_nodes, | |
2679 | dest_state->entrance_nodes, | |
2680 | new_dest_nodes); | |
2681 | if (BE (err != REG_NOERROR, 0)) | |
2682 | { | |
2683 | re_node_set_free (&dest_nodes); | |
2684 | goto free_return; | |
2685 | } | |
2686 | mctx->state_log[dest_str_idx] | |
2687 | = re_acquire_state_context (&err, dfa, &dest_nodes, context); | |
2688 | re_node_set_free (&dest_nodes); | |
2689 | if (BE (mctx->state_log[dest_str_idx] == NULL | |
2690 | && err != REG_NOERROR, 0)) | |
2691 | goto free_return; | |
2692 | } | |
2693 | /* We need to check recursively if the backreference can epsilon | |
2694 | transit. */ | |
2695 | if (subexp_len == 0 | |
2696 | && mctx->state_log[cur_str_idx]->nodes.nelem > prev_nelem) | |
2697 | { | |
2698 | err = check_subexp_matching_top (mctx, new_dest_nodes, | |
2699 | cur_str_idx); | |
2700 | if (BE (err != REG_NOERROR, 0)) | |
2701 | goto free_return; | |
2702 | err = transit_state_bkref (mctx, new_dest_nodes); | |
2703 | if (BE (err != REG_NOERROR, 0)) | |
2704 | goto free_return; | |
2705 | } | |
2706 | } | |
2707 | } | |
2708 | err = REG_NOERROR; | |
2709 | free_return: | |
2710 | return err; | |
2711 | } | |
2712 | ||
2713 | /* Enumerate all the candidates which the backreference BKREF_NODE can match | |
2714 | at BKREF_STR_IDX, and register them by match_ctx_add_entry(). | |
2715 | Note that we might collect inappropriate candidates here. | |
2716 | However, the cost of checking them strictly here is too high, then we | |
2717 | delay these checking for prune_impossible_nodes(). */ | |
2718 | ||
2719 | static reg_errcode_t | |
2720 | internal_function __attribute_warn_unused_result__ | |
2721 | get_subexp (re_match_context_t *mctx, Idx bkref_node, Idx bkref_str_idx) | |
2722 | { | |
2723 | const re_dfa_t *const dfa = mctx->dfa; | |
2724 | Idx subexp_num, sub_top_idx; | |
2725 | const char *buf = (const char *) re_string_get_buffer (&mctx->input); | |
2726 | /* Return if we have already checked BKREF_NODE at BKREF_STR_IDX. */ | |
2727 | Idx cache_idx = search_cur_bkref_entry (mctx, bkref_str_idx); | |
2728 | if (cache_idx != REG_MISSING) | |
2729 | { | |
2730 | const struct re_backref_cache_entry *entry | |
2731 | = mctx->bkref_ents + cache_idx; | |
2732 | do | |
2733 | if (entry->node == bkref_node) | |
2734 | return REG_NOERROR; /* We already checked it. */ | |
2735 | while (entry++->more); | |
2736 | } | |
2737 | ||
2738 | subexp_num = dfa->nodes[bkref_node].opr.idx; | |
2739 | ||
2740 | /* For each sub expression */ | |
2741 | for (sub_top_idx = 0; sub_top_idx < mctx->nsub_tops; ++sub_top_idx) | |
2742 | { | |
2743 | reg_errcode_t err; | |
2744 | re_sub_match_top_t *sub_top = mctx->sub_tops[sub_top_idx]; | |
2745 | re_sub_match_last_t *sub_last; | |
2746 | Idx sub_last_idx, sl_str, bkref_str_off; | |
2747 | ||
2748 | if (dfa->nodes[sub_top->node].opr.idx != subexp_num) | |
2749 | continue; /* It isn't related. */ | |
2750 | ||
2751 | sl_str = sub_top->str_idx; | |
2752 | bkref_str_off = bkref_str_idx; | |
2753 | /* At first, check the last node of sub expressions we already | |
2754 | evaluated. */ | |
2755 | for (sub_last_idx = 0; sub_last_idx < sub_top->nlasts; ++sub_last_idx) | |
2756 | { | |
2757 | regoff_t sl_str_diff; | |
2758 | sub_last = sub_top->lasts[sub_last_idx]; | |
2759 | sl_str_diff = sub_last->str_idx - sl_str; | |
2760 | /* The matched string by the sub expression match with the substring | |
2761 | at the back reference? */ | |
2762 | if (sl_str_diff > 0) | |
2763 | { | |
2764 | if (BE (bkref_str_off + sl_str_diff > mctx->input.valid_len, 0)) | |
2765 | { | |
2766 | /* Not enough chars for a successful match. */ | |
2767 | if (bkref_str_off + sl_str_diff > mctx->input.len) | |
2768 | break; | |
2769 | ||
2770 | err = clean_state_log_if_needed (mctx, | |
2771 | bkref_str_off | |
2772 | + sl_str_diff); | |
2773 | if (BE (err != REG_NOERROR, 0)) | |
2774 | return err; | |
2775 | buf = (const char *) re_string_get_buffer (&mctx->input); | |
2776 | } | |
2777 | if (memcmp (buf + bkref_str_off, buf + sl_str, sl_str_diff) != 0) | |
2778 | /* We don't need to search this sub expression any more. */ | |
2779 | break; | |
2780 | } | |
2781 | bkref_str_off += sl_str_diff; | |
2782 | sl_str += sl_str_diff; | |
2783 | err = get_subexp_sub (mctx, sub_top, sub_last, bkref_node, | |
2784 | bkref_str_idx); | |
2785 | ||
2786 | /* Reload buf, since the preceding call might have reallocated | |
2787 | the buffer. */ | |
2788 | buf = (const char *) re_string_get_buffer (&mctx->input); | |
2789 | ||
2790 | if (err == REG_NOMATCH) | |
2791 | continue; | |
2792 | if (BE (err != REG_NOERROR, 0)) | |
2793 | return err; | |
2794 | } | |
2795 | ||
2796 | if (sub_last_idx < sub_top->nlasts) | |
2797 | continue; | |
2798 | if (sub_last_idx > 0) | |
2799 | ++sl_str; | |
2800 | /* Then, search for the other last nodes of the sub expression. */ | |
2801 | for (; sl_str <= bkref_str_idx; ++sl_str) | |
2802 | { | |
2803 | Idx cls_node; | |
2804 | regoff_t sl_str_off; | |
2805 | const re_node_set *nodes; | |
2806 | sl_str_off = sl_str - sub_top->str_idx; | |
2807 | /* The matched string by the sub expression match with the substring | |
2808 | at the back reference? */ | |
2809 | if (sl_str_off > 0) | |
2810 | { | |
2811 | if (BE (bkref_str_off >= mctx->input.valid_len, 0)) | |
2812 | { | |
2813 | /* If we are at the end of the input, we cannot match. */ | |
2814 | if (bkref_str_off >= mctx->input.len) | |
2815 | break; | |
2816 | ||
2817 | err = extend_buffers (mctx); | |
2818 | if (BE (err != REG_NOERROR, 0)) | |
2819 | return err; | |
2820 | ||
2821 | buf = (const char *) re_string_get_buffer (&mctx->input); | |
2822 | } | |
2823 | if (buf [bkref_str_off++] != buf[sl_str - 1]) | |
2824 | break; /* We don't need to search this sub expression | |
2825 | any more. */ | |
2826 | } | |
2827 | if (mctx->state_log[sl_str] == NULL) | |
2828 | continue; | |
2829 | /* Does this state have a ')' of the sub expression? */ | |
2830 | nodes = &mctx->state_log[sl_str]->nodes; | |
2831 | cls_node = find_subexp_node (dfa, nodes, subexp_num, | |
2832 | OP_CLOSE_SUBEXP); | |
2833 | if (cls_node == REG_MISSING) | |
2834 | continue; /* No. */ | |
2835 | if (sub_top->path == NULL) | |
2836 | { | |
2837 | sub_top->path = calloc (sizeof (state_array_t), | |
2838 | sl_str - sub_top->str_idx + 1); | |
2839 | if (sub_top->path == NULL) | |
2840 | return REG_ESPACE; | |
2841 | } | |
2842 | /* Can the OP_OPEN_SUBEXP node arrive the OP_CLOSE_SUBEXP node | |
2843 | in the current context? */ | |
2844 | err = check_arrival (mctx, sub_top->path, sub_top->node, | |
2845 | sub_top->str_idx, cls_node, sl_str, | |
2846 | OP_CLOSE_SUBEXP); | |
2847 | if (err == REG_NOMATCH) | |
2848 | continue; | |
2849 | if (BE (err != REG_NOERROR, 0)) | |
2850 | return err; | |
2851 | sub_last = match_ctx_add_sublast (sub_top, cls_node, sl_str); | |
2852 | if (BE (sub_last == NULL, 0)) | |
2853 | return REG_ESPACE; | |
2854 | err = get_subexp_sub (mctx, sub_top, sub_last, bkref_node, | |
2855 | bkref_str_idx); | |
2856 | if (err == REG_NOMATCH) | |
2857 | continue; | |
2858 | } | |
2859 | } | |
2860 | return REG_NOERROR; | |
2861 | } | |
2862 | ||
2863 | /* Helper functions for get_subexp(). */ | |
2864 | ||
2865 | /* Check SUB_LAST can arrive to the back reference BKREF_NODE at BKREF_STR. | |
2866 | If it can arrive, register the sub expression expressed with SUB_TOP | |
2867 | and SUB_LAST. */ | |
2868 | ||
2869 | static reg_errcode_t | |
2870 | internal_function | |
2871 | get_subexp_sub (re_match_context_t *mctx, const re_sub_match_top_t *sub_top, | |
2872 | re_sub_match_last_t *sub_last, Idx bkref_node, Idx bkref_str) | |
2873 | { | |
2874 | reg_errcode_t err; | |
2875 | Idx to_idx; | |
2876 | /* Can the subexpression arrive the back reference? */ | |
2877 | err = check_arrival (mctx, &sub_last->path, sub_last->node, | |
2878 | sub_last->str_idx, bkref_node, bkref_str, | |
2879 | OP_OPEN_SUBEXP); | |
2880 | if (err != REG_NOERROR) | |
2881 | return err; | |
2882 | err = match_ctx_add_entry (mctx, bkref_node, bkref_str, sub_top->str_idx, | |
2883 | sub_last->str_idx); | |
2884 | if (BE (err != REG_NOERROR, 0)) | |
2885 | return err; | |
2886 | to_idx = bkref_str + sub_last->str_idx - sub_top->str_idx; | |
2887 | return clean_state_log_if_needed (mctx, to_idx); | |
2888 | } | |
2889 | ||
2890 | /* Find the first node which is '(' or ')' and whose index is SUBEXP_IDX. | |
2891 | Search '(' if FL_OPEN, or search ')' otherwise. | |
2892 | TODO: This function isn't efficient... | |
2893 | Because there might be more than one nodes whose types are | |
2894 | OP_OPEN_SUBEXP and whose index is SUBEXP_IDX, we must check all | |
2895 | nodes. | |
2896 | E.g. RE: (a){2} */ | |
2897 | ||
2898 | static Idx | |
2899 | internal_function | |
2900 | find_subexp_node (const re_dfa_t *dfa, const re_node_set *nodes, | |
2901 | Idx subexp_idx, int type) | |
2902 | { | |
2903 | Idx cls_idx; | |
2904 | for (cls_idx = 0; cls_idx < nodes->nelem; ++cls_idx) | |
2905 | { | |
2906 | Idx cls_node = nodes->elems[cls_idx]; | |
2907 | const re_token_t *node = dfa->nodes + cls_node; | |
2908 | if (node->type == type | |
2909 | && node->opr.idx == subexp_idx) | |
2910 | return cls_node; | |
2911 | } | |
2912 | return REG_MISSING; | |
2913 | } | |
2914 | ||
2915 | /* Check whether the node TOP_NODE at TOP_STR can arrive to the node | |
2916 | LAST_NODE at LAST_STR. We record the path onto PATH since it will be | |
2917 | heavily reused. | |
2918 | Return REG_NOERROR if it can arrive, or REG_NOMATCH otherwise. */ | |
2919 | ||
2920 | static reg_errcode_t | |
2921 | internal_function __attribute_warn_unused_result__ | |
2922 | check_arrival (re_match_context_t *mctx, state_array_t *path, Idx top_node, | |
2923 | Idx top_str, Idx last_node, Idx last_str, int type) | |
2924 | { | |
2925 | const re_dfa_t *const dfa = mctx->dfa; | |
2926 | reg_errcode_t err = REG_NOERROR; | |
2927 | Idx subexp_num, backup_cur_idx, str_idx, null_cnt; | |
2928 | re_dfastate_t *cur_state = NULL; | |
2929 | re_node_set *cur_nodes, next_nodes; | |
2930 | re_dfastate_t **backup_state_log; | |
2931 | unsigned int context; | |
2932 | ||
2933 | subexp_num = dfa->nodes[top_node].opr.idx; | |
2934 | /* Extend the buffer if we need. */ | |
2935 | if (BE (path->alloc < last_str + mctx->max_mb_elem_len + 1, 0)) | |
2936 | { | |
2937 | re_dfastate_t **new_array; | |
2938 | Idx old_alloc = path->alloc; | |
2939 | Idx new_alloc = old_alloc + last_str + mctx->max_mb_elem_len + 1; | |
2940 | if (BE (new_alloc < old_alloc, 0) | |
2941 | || BE (SIZE_MAX / sizeof (re_dfastate_t *) < new_alloc, 0)) | |
2942 | return REG_ESPACE; | |
2943 | new_array = re_realloc (path->array, re_dfastate_t *, new_alloc); | |
2944 | if (BE (new_array == NULL, 0)) | |
2945 | return REG_ESPACE; | |
2946 | path->array = new_array; | |
2947 | path->alloc = new_alloc; | |
2948 | memset (new_array + old_alloc, '\0', | |
2949 | sizeof (re_dfastate_t *) * (path->alloc - old_alloc)); | |
2950 | } | |
2951 | ||
2952 | str_idx = path->next_idx ? path->next_idx : top_str; | |
2953 | ||
2954 | /* Temporary modify MCTX. */ | |
2955 | backup_state_log = mctx->state_log; | |
2956 | backup_cur_idx = mctx->input.cur_idx; | |
2957 | mctx->state_log = path->array; | |
2958 | mctx->input.cur_idx = str_idx; | |
2959 | ||
2960 | /* Setup initial node set. */ | |
2961 | context = re_string_context_at (&mctx->input, str_idx - 1, mctx->eflags); | |
2962 | if (str_idx == top_str) | |
2963 | { | |
2964 | err = re_node_set_init_1 (&next_nodes, top_node); | |
2965 | if (BE (err != REG_NOERROR, 0)) | |
2966 | return err; | |
2967 | err = check_arrival_expand_ecl (dfa, &next_nodes, subexp_num, type); | |
2968 | if (BE (err != REG_NOERROR, 0)) | |
2969 | { | |
2970 | re_node_set_free (&next_nodes); | |
2971 | return err; | |
2972 | } | |
2973 | } | |
2974 | else | |
2975 | { | |
2976 | cur_state = mctx->state_log[str_idx]; | |
2977 | if (cur_state && cur_state->has_backref) | |
2978 | { | |
2979 | err = re_node_set_init_copy (&next_nodes, &cur_state->nodes); | |
2980 | if (BE (err != REG_NOERROR, 0)) | |
2981 | return err; | |
2982 | } | |
2983 | else | |
2984 | re_node_set_init_empty (&next_nodes); | |
2985 | } | |
2986 | if (str_idx == top_str || (cur_state && cur_state->has_backref)) | |
2987 | { | |
2988 | if (next_nodes.nelem) | |
2989 | { | |
2990 | err = expand_bkref_cache (mctx, &next_nodes, str_idx, | |
2991 | subexp_num, type); | |
2992 | if (BE (err != REG_NOERROR, 0)) | |
2993 | { | |
2994 | re_node_set_free (&next_nodes); | |
2995 | return err; | |
2996 | } | |
2997 | } | |
2998 | cur_state = re_acquire_state_context (&err, dfa, &next_nodes, context); | |
2999 | if (BE (cur_state == NULL && err != REG_NOERROR, 0)) | |
3000 | { | |
3001 | re_node_set_free (&next_nodes); | |
3002 | return err; | |
3003 | } | |
3004 | mctx->state_log[str_idx] = cur_state; | |
3005 | } | |
3006 | ||
3007 | for (null_cnt = 0; str_idx < last_str && null_cnt <= mctx->max_mb_elem_len;) | |
3008 | { | |
3009 | re_node_set_empty (&next_nodes); | |
3010 | if (mctx->state_log[str_idx + 1]) | |
3011 | { | |
3012 | err = re_node_set_merge (&next_nodes, | |
3013 | &mctx->state_log[str_idx + 1]->nodes); | |
3014 | if (BE (err != REG_NOERROR, 0)) | |
3015 | { | |
3016 | re_node_set_free (&next_nodes); | |
3017 | return err; | |
3018 | } | |
3019 | } | |
3020 | if (cur_state) | |
3021 | { | |
3022 | err = check_arrival_add_next_nodes (mctx, str_idx, | |
3023 | &cur_state->non_eps_nodes, | |
3024 | &next_nodes); | |
3025 | if (BE (err != REG_NOERROR, 0)) | |
3026 | { | |
3027 | re_node_set_free (&next_nodes); | |
3028 | return err; | |
3029 | } | |
3030 | } | |
3031 | ++str_idx; | |
3032 | if (next_nodes.nelem) | |
3033 | { | |
3034 | err = check_arrival_expand_ecl (dfa, &next_nodes, subexp_num, type); | |
3035 | if (BE (err != REG_NOERROR, 0)) | |
3036 | { | |
3037 | re_node_set_free (&next_nodes); | |
3038 | return err; | |
3039 | } | |
3040 | err = expand_bkref_cache (mctx, &next_nodes, str_idx, | |
3041 | subexp_num, type); | |
3042 | if (BE (err != REG_NOERROR, 0)) | |
3043 | { | |
3044 | re_node_set_free (&next_nodes); | |
3045 | return err; | |
3046 | } | |
3047 | } | |
3048 | context = re_string_context_at (&mctx->input, str_idx - 1, mctx->eflags); | |
3049 | cur_state = re_acquire_state_context (&err, dfa, &next_nodes, context); | |
3050 | if (BE (cur_state == NULL && err != REG_NOERROR, 0)) | |
3051 | { | |
3052 | re_node_set_free (&next_nodes); | |
3053 | return err; | |
3054 | } | |
3055 | mctx->state_log[str_idx] = cur_state; | |
3056 | null_cnt = cur_state == NULL ? null_cnt + 1 : 0; | |
3057 | } | |
3058 | re_node_set_free (&next_nodes); | |
3059 | cur_nodes = (mctx->state_log[last_str] == NULL ? NULL | |
3060 | : &mctx->state_log[last_str]->nodes); | |
3061 | path->next_idx = str_idx; | |
3062 | ||
3063 | /* Fix MCTX. */ | |
3064 | mctx->state_log = backup_state_log; | |
3065 | mctx->input.cur_idx = backup_cur_idx; | |
3066 | ||
3067 | /* Then check the current node set has the node LAST_NODE. */ | |
3068 | if (cur_nodes != NULL && re_node_set_contains (cur_nodes, last_node)) | |
3069 | return REG_NOERROR; | |
3070 | ||
3071 | return REG_NOMATCH; | |
3072 | } | |
3073 | ||
3074 | /* Helper functions for check_arrival. */ | |
3075 | ||
3076 | /* Calculate the destination nodes of CUR_NODES at STR_IDX, and append them | |
3077 | to NEXT_NODES. | |
3078 | TODO: This function is similar to the functions transit_state*(), | |
3079 | however this function has many additional works. | |
3080 | Can't we unify them? */ | |
3081 | ||
3082 | static reg_errcode_t | |
3083 | internal_function __attribute_warn_unused_result__ | |
3084 | check_arrival_add_next_nodes (re_match_context_t *mctx, Idx str_idx, | |
3085 | re_node_set *cur_nodes, re_node_set *next_nodes) | |
3086 | { | |
3087 | const re_dfa_t *const dfa = mctx->dfa; | |
3088 | bool ok; | |
3089 | Idx cur_idx; | |
3090 | #ifdef RE_ENABLE_I18N | |
3091 | reg_errcode_t err = REG_NOERROR; | |
3092 | #endif | |
3093 | re_node_set union_set; | |
3094 | re_node_set_init_empty (&union_set); | |
3095 | for (cur_idx = 0; cur_idx < cur_nodes->nelem; ++cur_idx) | |
3096 | { | |
3097 | int naccepted = 0; | |
3098 | Idx cur_node = cur_nodes->elems[cur_idx]; | |
3099 | #ifdef DEBUG | |
3100 | re_token_type_t type = dfa->nodes[cur_node].type; | |
3101 | assert (!IS_EPSILON_NODE (type)); | |
3102 | #endif | |
3103 | #ifdef RE_ENABLE_I18N | |
3104 | /* If the node may accept "multi byte". */ | |
3105 | if (dfa->nodes[cur_node].accept_mb) | |
3106 | { | |
3107 | naccepted = check_node_accept_bytes (dfa, cur_node, &mctx->input, | |
3108 | str_idx); | |
3109 | if (naccepted > 1) | |
3110 | { | |
3111 | re_dfastate_t *dest_state; | |
3112 | Idx next_node = dfa->nexts[cur_node]; | |
3113 | Idx next_idx = str_idx + naccepted; | |
3114 | dest_state = mctx->state_log[next_idx]; | |
3115 | re_node_set_empty (&union_set); | |
3116 | if (dest_state) | |
3117 | { | |
3118 | err = re_node_set_merge (&union_set, &dest_state->nodes); | |
3119 | if (BE (err != REG_NOERROR, 0)) | |
3120 | { | |
3121 | re_node_set_free (&union_set); | |
3122 | return err; | |
3123 | } | |
3124 | } | |
3125 | ok = re_node_set_insert (&union_set, next_node); | |
3126 | if (BE (! ok, 0)) | |
3127 | { | |
3128 | re_node_set_free (&union_set); | |
3129 | return REG_ESPACE; | |
3130 | } | |
3131 | mctx->state_log[next_idx] = re_acquire_state (&err, dfa, | |
3132 | &union_set); | |
3133 | if (BE (mctx->state_log[next_idx] == NULL | |
3134 | && err != REG_NOERROR, 0)) | |
3135 | { | |
3136 | re_node_set_free (&union_set); | |
3137 | return err; | |
3138 | } | |
3139 | } | |
3140 | } | |
3141 | #endif /* RE_ENABLE_I18N */ | |
3142 | if (naccepted | |
3143 | || check_node_accept (mctx, dfa->nodes + cur_node, str_idx)) | |
3144 | { | |
3145 | ok = re_node_set_insert (next_nodes, dfa->nexts[cur_node]); | |
3146 | if (BE (! ok, 0)) | |
3147 | { | |
3148 | re_node_set_free (&union_set); | |
3149 | return REG_ESPACE; | |
3150 | } | |
3151 | } | |
3152 | } | |
3153 | re_node_set_free (&union_set); | |
3154 | return REG_NOERROR; | |
3155 | } | |
3156 | ||
3157 | /* For all the nodes in CUR_NODES, add the epsilon closures of them to | |
3158 | CUR_NODES, however exclude the nodes which are: | |
3159 | - inside the sub expression whose number is EX_SUBEXP, if FL_OPEN. | |
3160 | - out of the sub expression whose number is EX_SUBEXP, if !FL_OPEN. | |
3161 | */ | |
3162 | ||
3163 | static reg_errcode_t | |
3164 | internal_function | |
3165 | check_arrival_expand_ecl (const re_dfa_t *dfa, re_node_set *cur_nodes, | |
3166 | Idx ex_subexp, int type) | |
3167 | { | |
3168 | reg_errcode_t err; | |
3169 | Idx idx, outside_node; | |
3170 | re_node_set new_nodes; | |
3171 | #ifdef DEBUG | |
3172 | assert (cur_nodes->nelem); | |
3173 | #endif | |
3174 | err = re_node_set_alloc (&new_nodes, cur_nodes->nelem); | |
3175 | if (BE (err != REG_NOERROR, 0)) | |
3176 | return err; | |
3177 | /* Create a new node set NEW_NODES with the nodes which are epsilon | |
3178 | closures of the node in CUR_NODES. */ | |
3179 | ||
3180 | for (idx = 0; idx < cur_nodes->nelem; ++idx) | |
3181 | { | |
3182 | Idx cur_node = cur_nodes->elems[idx]; | |
3183 | const re_node_set *eclosure = dfa->eclosures + cur_node; | |
3184 | outside_node = find_subexp_node (dfa, eclosure, ex_subexp, type); | |
3185 | if (outside_node == REG_MISSING) | |
3186 | { | |
3187 | /* There are no problematic nodes, just merge them. */ | |
3188 | err = re_node_set_merge (&new_nodes, eclosure); | |
3189 | if (BE (err != REG_NOERROR, 0)) | |
3190 | { | |
3191 | re_node_set_free (&new_nodes); | |
3192 | return err; | |
3193 | } | |
3194 | } | |
3195 | else | |
3196 | { | |
3197 | /* There are problematic nodes, re-calculate incrementally. */ | |
3198 | err = check_arrival_expand_ecl_sub (dfa, &new_nodes, cur_node, | |
3199 | ex_subexp, type); | |
3200 | if (BE (err != REG_NOERROR, 0)) | |
3201 | { | |
3202 | re_node_set_free (&new_nodes); | |
3203 | return err; | |
3204 | } | |
3205 | } | |
3206 | } | |
3207 | re_node_set_free (cur_nodes); | |
3208 | *cur_nodes = new_nodes; | |
3209 | return REG_NOERROR; | |
3210 | } | |
3211 | ||
3212 | /* Helper function for check_arrival_expand_ecl. | |
3213 | Check incrementally the epsilon closure of TARGET, and if it isn't | |
3214 | problematic append it to DST_NODES. */ | |
3215 | ||
3216 | static reg_errcode_t | |
3217 | internal_function __attribute_warn_unused_result__ | |
3218 | check_arrival_expand_ecl_sub (const re_dfa_t *dfa, re_node_set *dst_nodes, | |
3219 | Idx target, Idx ex_subexp, int type) | |
3220 | { | |
3221 | Idx cur_node; | |
3222 | for (cur_node = target; !re_node_set_contains (dst_nodes, cur_node);) | |
3223 | { | |
3224 | bool ok; | |
3225 | ||
3226 | if (dfa->nodes[cur_node].type == type | |
3227 | && dfa->nodes[cur_node].opr.idx == ex_subexp) | |
3228 | { | |
3229 | if (type == OP_CLOSE_SUBEXP) | |
3230 | { | |
3231 | ok = re_node_set_insert (dst_nodes, cur_node); | |
3232 | if (BE (! ok, 0)) | |
3233 | return REG_ESPACE; | |
3234 | } | |
3235 | break; | |
3236 | } | |
3237 | ok = re_node_set_insert (dst_nodes, cur_node); | |
3238 | if (BE (! ok, 0)) | |
3239 | return REG_ESPACE; | |
3240 | if (dfa->edests[cur_node].nelem == 0) | |
3241 | break; | |
3242 | if (dfa->edests[cur_node].nelem == 2) | |
3243 | { | |
3244 | reg_errcode_t err; | |
3245 | err = check_arrival_expand_ecl_sub (dfa, dst_nodes, | |
3246 | dfa->edests[cur_node].elems[1], | |
3247 | ex_subexp, type); | |
3248 | if (BE (err != REG_NOERROR, 0)) | |
3249 | return err; | |
3250 | } | |
3251 | cur_node = dfa->edests[cur_node].elems[0]; | |
3252 | } | |
3253 | return REG_NOERROR; | |
3254 | } | |
3255 | ||
3256 | ||
3257 | /* For all the back references in the current state, calculate the | |
3258 | destination of the back references by the appropriate entry | |
3259 | in MCTX->BKREF_ENTS. */ | |
3260 | ||
3261 | static reg_errcode_t | |
3262 | internal_function __attribute_warn_unused_result__ | |
3263 | expand_bkref_cache (re_match_context_t *mctx, re_node_set *cur_nodes, | |
3264 | Idx cur_str, Idx subexp_num, int type) | |
3265 | { | |
3266 | const re_dfa_t *const dfa = mctx->dfa; | |
3267 | reg_errcode_t err; | |
3268 | Idx cache_idx_start = search_cur_bkref_entry (mctx, cur_str); | |
3269 | struct re_backref_cache_entry *ent; | |
3270 | ||
3271 | if (cache_idx_start == REG_MISSING) | |
3272 | return REG_NOERROR; | |
3273 | ||
3274 | restart: | |
3275 | ent = mctx->bkref_ents + cache_idx_start; | |
3276 | do | |
3277 | { | |
3278 | Idx to_idx, next_node; | |
3279 | ||
3280 | /* Is this entry ENT is appropriate? */ | |
3281 | if (!re_node_set_contains (cur_nodes, ent->node)) | |
3282 | continue; /* No. */ | |
3283 | ||
3284 | to_idx = cur_str + ent->subexp_to - ent->subexp_from; | |
3285 | /* Calculate the destination of the back reference, and append it | |
3286 | to MCTX->STATE_LOG. */ | |
3287 | if (to_idx == cur_str) | |
3288 | { | |
3289 | /* The backreference did epsilon transit, we must re-check all the | |
3290 | node in the current state. */ | |
3291 | re_node_set new_dests; | |
3292 | reg_errcode_t err2, err3; | |
3293 | next_node = dfa->edests[ent->node].elems[0]; | |
3294 | if (re_node_set_contains (cur_nodes, next_node)) | |
3295 | continue; | |
3296 | err = re_node_set_init_1 (&new_dests, next_node); | |
3297 | err2 = check_arrival_expand_ecl (dfa, &new_dests, subexp_num, type); | |
3298 | err3 = re_node_set_merge (cur_nodes, &new_dests); | |
3299 | re_node_set_free (&new_dests); | |
3300 | if (BE (err != REG_NOERROR || err2 != REG_NOERROR | |
3301 | || err3 != REG_NOERROR, 0)) | |
3302 | { | |
3303 | err = (err != REG_NOERROR ? err | |
3304 | : (err2 != REG_NOERROR ? err2 : err3)); | |
3305 | return err; | |
3306 | } | |
3307 | /* TODO: It is still inefficient... */ | |
3308 | goto restart; | |
3309 | } | |
3310 | else | |
3311 | { | |
3312 | re_node_set union_set; | |
3313 | next_node = dfa->nexts[ent->node]; | |
3314 | if (mctx->state_log[to_idx]) | |
3315 | { | |
3316 | bool ok; | |
3317 | if (re_node_set_contains (&mctx->state_log[to_idx]->nodes, | |
3318 | next_node)) | |
3319 | continue; | |
3320 | err = re_node_set_init_copy (&union_set, | |
3321 | &mctx->state_log[to_idx]->nodes); | |
3322 | ok = re_node_set_insert (&union_set, next_node); | |
3323 | if (BE (err != REG_NOERROR || ! ok, 0)) | |
3324 | { | |
3325 | re_node_set_free (&union_set); | |
3326 | err = err != REG_NOERROR ? err : REG_ESPACE; | |
3327 | return err; | |
3328 | } | |
3329 | } | |
3330 | else | |
3331 | { | |
3332 | err = re_node_set_init_1 (&union_set, next_node); | |
3333 | if (BE (err != REG_NOERROR, 0)) | |
3334 | return err; | |
3335 | } | |
3336 | mctx->state_log[to_idx] = re_acquire_state (&err, dfa, &union_set); | |
3337 | re_node_set_free (&union_set); | |
3338 | if (BE (mctx->state_log[to_idx] == NULL | |
3339 | && err != REG_NOERROR, 0)) | |
3340 | return err; | |
3341 | } | |
3342 | } | |
3343 | while (ent++->more); | |
3344 | return REG_NOERROR; | |
3345 | } | |
3346 | ||
3347 | /* Build transition table for the state. | |
3348 | Return true if successful. */ | |
3349 | ||
3350 | static bool | |
3351 | internal_function | |
3352 | build_trtable (const re_dfa_t *dfa, re_dfastate_t *state) | |
3353 | { | |
3354 | reg_errcode_t err; | |
3355 | Idx i, j; | |
3356 | int ch; | |
3357 | bool need_word_trtable = false; | |
3358 | bitset_word_t elem, mask; | |
3359 | bool dests_node_malloced = false; | |
3360 | bool dest_states_malloced = false; | |
3361 | Idx ndests; /* Number of the destination states from 'state'. */ | |
3362 | re_dfastate_t **trtable; | |
3363 | re_dfastate_t **dest_states = NULL, **dest_states_word, **dest_states_nl; | |
3364 | re_node_set follows, *dests_node; | |
3365 | bitset_t *dests_ch; | |
3366 | bitset_t acceptable; | |
3367 | ||
3368 | struct dests_alloc | |
3369 | { | |
3370 | re_node_set dests_node[SBC_MAX]; | |
3371 | bitset_t dests_ch[SBC_MAX]; | |
3372 | } *dests_alloc; | |
3373 | ||
3374 | /* We build DFA states which corresponds to the destination nodes | |
3375 | from 'state'. 'dests_node[i]' represents the nodes which i-th | |
3376 | destination state contains, and 'dests_ch[i]' represents the | |
3377 | characters which i-th destination state accepts. */ | |
3378 | if (__libc_use_alloca (sizeof (struct dests_alloc))) | |
3379 | dests_alloc = (struct dests_alloc *) alloca (sizeof (struct dests_alloc)); | |
3380 | else | |
3381 | { | |
3382 | dests_alloc = re_malloc (struct dests_alloc, 1); | |
3383 | if (BE (dests_alloc == NULL, 0)) | |
3384 | return false; | |
3385 | dests_node_malloced = true; | |
3386 | } | |
3387 | dests_node = dests_alloc->dests_node; | |
3388 | dests_ch = dests_alloc->dests_ch; | |
3389 | ||
3390 | /* Initialize transiton table. */ | |
3391 | state->word_trtable = state->trtable = NULL; | |
3392 | ||
3393 | /* At first, group all nodes belonging to 'state' into several | |
3394 | destinations. */ | |
3395 | ndests = group_nodes_into_DFAstates (dfa, state, dests_node, dests_ch); | |
3396 | if (BE (! REG_VALID_NONZERO_INDEX (ndests), 0)) | |
3397 | { | |
3398 | if (dests_node_malloced) | |
3399 | free (dests_alloc); | |
3400 | if (ndests == 0) | |
3401 | { | |
3402 | state->trtable = (re_dfastate_t **) | |
3403 | calloc (sizeof (re_dfastate_t *), SBC_MAX); | |
3404 | if (BE (state->trtable == NULL, 0)) | |
3405 | return false; | |
3406 | return true; | |
3407 | } | |
3408 | return false; | |
3409 | } | |
3410 | ||
3411 | err = re_node_set_alloc (&follows, ndests + 1); | |
3412 | if (BE (err != REG_NOERROR, 0)) | |
3413 | goto out_free; | |
3414 | ||
3415 | /* Avoid arithmetic overflow in size calculation. */ | |
3416 | if (BE ((((SIZE_MAX - (sizeof (re_node_set) + sizeof (bitset_t)) * SBC_MAX) | |
3417 | / (3 * sizeof (re_dfastate_t *))) | |
3418 | < ndests), | |
3419 | 0)) | |
3420 | goto out_free; | |
3421 | ||
3422 | if (__libc_use_alloca ((sizeof (re_node_set) + sizeof (bitset_t)) * SBC_MAX | |
3423 | + ndests * 3 * sizeof (re_dfastate_t *))) | |
3424 | dest_states = (re_dfastate_t **) | |
3425 | alloca (ndests * 3 * sizeof (re_dfastate_t *)); | |
3426 | else | |
3427 | { | |
3428 | dest_states = (re_dfastate_t **) | |
3429 | malloc (ndests * 3 * sizeof (re_dfastate_t *)); | |
3430 | if (BE (dest_states == NULL, 0)) | |
3431 | { | |
3432 | out_free: | |
3433 | if (dest_states_malloced) | |
3434 | free (dest_states); | |
3435 | re_node_set_free (&follows); | |
3436 | for (i = 0; i < ndests; ++i) | |
3437 | re_node_set_free (dests_node + i); | |
3438 | if (dests_node_malloced) | |
3439 | free (dests_alloc); | |
3440 | return false; | |
3441 | } | |
3442 | dest_states_malloced = true; | |
3443 | } | |
3444 | dest_states_word = dest_states + ndests; | |
3445 | dest_states_nl = dest_states_word + ndests; | |
3446 | bitset_empty (acceptable); | |
3447 | ||
3448 | /* Then build the states for all destinations. */ | |
3449 | for (i = 0; i < ndests; ++i) | |
3450 | { | |
3451 | Idx next_node; | |
3452 | re_node_set_empty (&follows); | |
3453 | /* Merge the follows of this destination states. */ | |
3454 | for (j = 0; j < dests_node[i].nelem; ++j) | |
3455 | { | |
3456 | next_node = dfa->nexts[dests_node[i].elems[j]]; | |
3457 | if (next_node != REG_MISSING) | |
3458 | { | |
3459 | err = re_node_set_merge (&follows, dfa->eclosures + next_node); | |
3460 | if (BE (err != REG_NOERROR, 0)) | |
3461 | goto out_free; | |
3462 | } | |
3463 | } | |
3464 | dest_states[i] = re_acquire_state_context (&err, dfa, &follows, 0); | |
3465 | if (BE (dest_states[i] == NULL && err != REG_NOERROR, 0)) | |
3466 | goto out_free; | |
3467 | /* If the new state has context constraint, | |
3468 | build appropriate states for these contexts. */ | |
3469 | if (dest_states[i]->has_constraint) | |
3470 | { | |
3471 | dest_states_word[i] = re_acquire_state_context (&err, dfa, &follows, | |
3472 | CONTEXT_WORD); | |
3473 | if (BE (dest_states_word[i] == NULL && err != REG_NOERROR, 0)) | |
3474 | goto out_free; | |
3475 | ||
3476 | if (dest_states[i] != dest_states_word[i] && dfa->mb_cur_max > 1) | |
3477 | need_word_trtable = true; | |
3478 | ||
3479 | dest_states_nl[i] = re_acquire_state_context (&err, dfa, &follows, | |
3480 | CONTEXT_NEWLINE); | |
3481 | if (BE (dest_states_nl[i] == NULL && err != REG_NOERROR, 0)) | |
3482 | goto out_free; | |
3483 | } | |
3484 | else | |
3485 | { | |
3486 | dest_states_word[i] = dest_states[i]; | |
3487 | dest_states_nl[i] = dest_states[i]; | |
3488 | } | |
3489 | bitset_merge (acceptable, dests_ch[i]); | |
3490 | } | |
3491 | ||
3492 | if (!BE (need_word_trtable, 0)) | |
3493 | { | |
3494 | /* We don't care about whether the following character is a word | |
3495 | character, or we are in a single-byte character set so we can | |
3496 | discern by looking at the character code: allocate a | |
3497 | 256-entry transition table. */ | |
3498 | trtable = state->trtable = | |
3499 | (re_dfastate_t **) calloc (sizeof (re_dfastate_t *), SBC_MAX); | |
3500 | if (BE (trtable == NULL, 0)) | |
3501 | goto out_free; | |
3502 | ||
3503 | /* For all characters ch...: */ | |
3504 | for (i = 0; i < BITSET_WORDS; ++i) | |
3505 | for (ch = i * BITSET_WORD_BITS, elem = acceptable[i], mask = 1; | |
3506 | elem; | |
3507 | mask <<= 1, elem >>= 1, ++ch) | |
3508 | if (BE (elem & 1, 0)) | |
3509 | { | |
3510 | /* There must be exactly one destination which accepts | |
3511 | character ch. See group_nodes_into_DFAstates. */ | |
3512 | for (j = 0; (dests_ch[j][i] & mask) == 0; ++j) | |
3513 | ; | |
3514 | ||
3515 | /* j-th destination accepts the word character ch. */ | |
3516 | if (dfa->word_char[i] & mask) | |
3517 | trtable[ch] = dest_states_word[j]; | |
3518 | else | |
3519 | trtable[ch] = dest_states[j]; | |
3520 | } | |
3521 | } | |
3522 | else | |
3523 | { | |
3524 | /* We care about whether the following character is a word | |
3525 | character, and we are in a multi-byte character set: discern | |
3526 | by looking at the character code: build two 256-entry | |
3527 | transition tables, one starting at trtable[0] and one | |
3528 | starting at trtable[SBC_MAX]. */ | |
3529 | trtable = state->word_trtable = | |
3530 | (re_dfastate_t **) calloc (sizeof (re_dfastate_t *), 2 * SBC_MAX); | |
3531 | if (BE (trtable == NULL, 0)) | |
3532 | goto out_free; | |
3533 | ||
3534 | /* For all characters ch...: */ | |
3535 | for (i = 0; i < BITSET_WORDS; ++i) | |
3536 | for (ch = i * BITSET_WORD_BITS, elem = acceptable[i], mask = 1; | |
3537 | elem; | |
3538 | mask <<= 1, elem >>= 1, ++ch) | |
3539 | if (BE (elem & 1, 0)) | |
3540 | { | |
3541 | /* There must be exactly one destination which accepts | |
3542 | character ch. See group_nodes_into_DFAstates. */ | |
3543 | for (j = 0; (dests_ch[j][i] & mask) == 0; ++j) | |
3544 | ; | |
3545 | ||
3546 | /* j-th destination accepts the word character ch. */ | |
3547 | trtable[ch] = dest_states[j]; | |
3548 | trtable[ch + SBC_MAX] = dest_states_word[j]; | |
3549 | } | |
3550 | } | |
3551 | ||
3552 | /* new line */ | |
3553 | if (bitset_contain (acceptable, NEWLINE_CHAR)) | |
3554 | { | |
3555 | /* The current state accepts newline character. */ | |
3556 | for (j = 0; j < ndests; ++j) | |
3557 | if (bitset_contain (dests_ch[j], NEWLINE_CHAR)) | |
3558 | { | |
3559 | /* k-th destination accepts newline character. */ | |
3560 | trtable[NEWLINE_CHAR] = dest_states_nl[j]; | |
3561 | if (need_word_trtable) | |
3562 | trtable[NEWLINE_CHAR + SBC_MAX] = dest_states_nl[j]; | |
3563 | /* There must be only one destination which accepts | |
3564 | newline. See group_nodes_into_DFAstates. */ | |
3565 | break; | |
3566 | } | |
3567 | } | |
3568 | ||
3569 | if (dest_states_malloced) | |
3570 | free (dest_states); | |
3571 | ||
3572 | re_node_set_free (&follows); | |
3573 | for (i = 0; i < ndests; ++i) | |
3574 | re_node_set_free (dests_node + i); | |
3575 | ||
3576 | if (dests_node_malloced) | |
3577 | free (dests_alloc); | |
3578 | ||
3579 | return true; | |
3580 | } | |
3581 | ||
3582 | /* Group all nodes belonging to STATE into several destinations. | |
3583 | Then for all destinations, set the nodes belonging to the destination | |
3584 | to DESTS_NODE[i] and set the characters accepted by the destination | |
3585 | to DEST_CH[i]. This function return the number of destinations. */ | |
3586 | ||
3587 | static Idx | |
3588 | internal_function | |
3589 | group_nodes_into_DFAstates (const re_dfa_t *dfa, const re_dfastate_t *state, | |
3590 | re_node_set *dests_node, bitset_t *dests_ch) | |
3591 | { | |
3592 | reg_errcode_t err; | |
3593 | bool ok; | |
3594 | Idx i, j, k; | |
3595 | Idx ndests; /* Number of the destinations from 'state'. */ | |
3596 | bitset_t accepts; /* Characters a node can accept. */ | |
3597 | const re_node_set *cur_nodes = &state->nodes; | |
3598 | bitset_empty (accepts); | |
3599 | ndests = 0; | |
3600 | ||
3601 | /* For all the nodes belonging to 'state', */ | |
3602 | for (i = 0; i < cur_nodes->nelem; ++i) | |
3603 | { | |
3604 | re_token_t *node = &dfa->nodes[cur_nodes->elems[i]]; | |
3605 | re_token_type_t type = node->type; | |
3606 | unsigned int constraint = node->constraint; | |
3607 | ||
3608 | /* Enumerate all single byte character this node can accept. */ | |
3609 | if (type == CHARACTER) | |
3610 | bitset_set (accepts, node->opr.c); | |
3611 | else if (type == SIMPLE_BRACKET) | |
3612 | { | |
3613 | bitset_merge (accepts, node->opr.sbcset); | |
3614 | } | |
3615 | else if (type == OP_PERIOD) | |
3616 | { | |
3617 | #ifdef RE_ENABLE_I18N | |
3618 | if (dfa->mb_cur_max > 1) | |
3619 | bitset_merge (accepts, dfa->sb_char); | |
3620 | else | |
3621 | #endif | |
3622 | bitset_set_all (accepts); | |
3623 | if (!(dfa->syntax & RE_DOT_NEWLINE)) | |
3624 | bitset_clear (accepts, '\n'); | |
3625 | if (dfa->syntax & RE_DOT_NOT_NULL) | |
3626 | bitset_clear (accepts, '\0'); | |
3627 | } | |
3628 | #ifdef RE_ENABLE_I18N | |
3629 | else if (type == OP_UTF8_PERIOD) | |
3630 | { | |
3631 | if (ASCII_CHARS % BITSET_WORD_BITS == 0) | |
3632 | memset (accepts, -1, ASCII_CHARS / CHAR_BIT); | |
3633 | else | |
3634 | bitset_merge (accepts, utf8_sb_map); | |
3635 | if (!(dfa->syntax & RE_DOT_NEWLINE)) | |
3636 | bitset_clear (accepts, '\n'); | |
3637 | if (dfa->syntax & RE_DOT_NOT_NULL) | |
3638 | bitset_clear (accepts, '\0'); | |
3639 | } | |
3640 | #endif | |
3641 | else | |
3642 | continue; | |
3643 | ||
3644 | /* Check the 'accepts' and sift the characters which are not | |
3645 | match it the context. */ | |
3646 | if (constraint) | |
3647 | { | |
3648 | if (constraint & NEXT_NEWLINE_CONSTRAINT) | |
3649 | { | |
3650 | bool accepts_newline = bitset_contain (accepts, NEWLINE_CHAR); | |
3651 | bitset_empty (accepts); | |
3652 | if (accepts_newline) | |
3653 | bitset_set (accepts, NEWLINE_CHAR); | |
3654 | else | |
3655 | continue; | |
3656 | } | |
3657 | if (constraint & NEXT_ENDBUF_CONSTRAINT) | |
3658 | { | |
3659 | bitset_empty (accepts); | |
3660 | continue; | |
3661 | } | |
3662 | ||
3663 | if (constraint & NEXT_WORD_CONSTRAINT) | |
3664 | { | |
3665 | bitset_word_t any_set = 0; | |
3666 | if (type == CHARACTER && !node->word_char) | |
3667 | { | |
3668 | bitset_empty (accepts); | |
3669 | continue; | |
3670 | } | |
3671 | #ifdef RE_ENABLE_I18N | |
3672 | if (dfa->mb_cur_max > 1) | |
3673 | for (j = 0; j < BITSET_WORDS; ++j) | |
3674 | any_set |= (accepts[j] &= (dfa->word_char[j] | ~dfa->sb_char[j])); | |
3675 | else | |
3676 | #endif | |
3677 | for (j = 0; j < BITSET_WORDS; ++j) | |
3678 | any_set |= (accepts[j] &= dfa->word_char[j]); | |
3679 | if (!any_set) | |
3680 | continue; | |
3681 | } | |
3682 | if (constraint & NEXT_NOTWORD_CONSTRAINT) | |
3683 | { | |
3684 | bitset_word_t any_set = 0; | |
3685 | if (type == CHARACTER && node->word_char) | |
3686 | { | |
3687 | bitset_empty (accepts); | |
3688 | continue; | |
3689 | } | |
3690 | #ifdef RE_ENABLE_I18N | |
3691 | if (dfa->mb_cur_max > 1) | |
3692 | for (j = 0; j < BITSET_WORDS; ++j) | |
3693 | any_set |= (accepts[j] &= ~(dfa->word_char[j] & dfa->sb_char[j])); | |
3694 | else | |
3695 | #endif | |
3696 | for (j = 0; j < BITSET_WORDS; ++j) | |
3697 | any_set |= (accepts[j] &= ~dfa->word_char[j]); | |
3698 | if (!any_set) | |
3699 | continue; | |
3700 | } | |
3701 | } | |
3702 | ||
3703 | /* Then divide 'accepts' into DFA states, or create a new | |
3704 | state. Above, we make sure that accepts is not empty. */ | |
3705 | for (j = 0; j < ndests; ++j) | |
3706 | { | |
3707 | bitset_t intersec; /* Intersection sets, see below. */ | |
3708 | bitset_t remains; | |
3709 | /* Flags, see below. */ | |
3710 | bitset_word_t has_intersec, not_subset, not_consumed; | |
3711 | ||
3712 | /* Optimization, skip if this state doesn't accept the character. */ | |
3713 | if (type == CHARACTER && !bitset_contain (dests_ch[j], node->opr.c)) | |
3714 | continue; | |
3715 | ||
3716 | /* Enumerate the intersection set of this state and 'accepts'. */ | |
3717 | has_intersec = 0; | |
3718 | for (k = 0; k < BITSET_WORDS; ++k) | |
3719 | has_intersec |= intersec[k] = accepts[k] & dests_ch[j][k]; | |
3720 | /* And skip if the intersection set is empty. */ | |
3721 | if (!has_intersec) | |
3722 | continue; | |
3723 | ||
3724 | /* Then check if this state is a subset of 'accepts'. */ | |
3725 | not_subset = not_consumed = 0; | |
3726 | for (k = 0; k < BITSET_WORDS; ++k) | |
3727 | { | |
3728 | not_subset |= remains[k] = ~accepts[k] & dests_ch[j][k]; | |
3729 | not_consumed |= accepts[k] = accepts[k] & ~dests_ch[j][k]; | |
3730 | } | |
3731 | ||
3732 | /* If this state isn't a subset of 'accepts', create a | |
3733 | new group state, which has the 'remains'. */ | |
3734 | if (not_subset) | |
3735 | { | |
3736 | bitset_copy (dests_ch[ndests], remains); | |
3737 | bitset_copy (dests_ch[j], intersec); | |
3738 | err = re_node_set_init_copy (dests_node + ndests, &dests_node[j]); | |
3739 | if (BE (err != REG_NOERROR, 0)) | |
3740 | goto error_return; | |
3741 | ++ndests; | |
3742 | } | |
3743 | ||
3744 | /* Put the position in the current group. */ | |
3745 | ok = re_node_set_insert (&dests_node[j], cur_nodes->elems[i]); | |
3746 | if (BE (! ok, 0)) | |
3747 | goto error_return; | |
3748 | ||
3749 | /* If all characters are consumed, go to next node. */ | |
3750 | if (!not_consumed) | |
3751 | break; | |
3752 | } | |
3753 | /* Some characters remain, create a new group. */ | |
3754 | if (j == ndests) | |
3755 | { | |
3756 | bitset_copy (dests_ch[ndests], accepts); | |
3757 | err = re_node_set_init_1 (dests_node + ndests, cur_nodes->elems[i]); | |
3758 | if (BE (err != REG_NOERROR, 0)) | |
3759 | goto error_return; | |
3760 | ++ndests; | |
3761 | bitset_empty (accepts); | |
3762 | } | |
3763 | } | |
3764 | return ndests; | |
3765 | error_return: | |
3766 | for (j = 0; j < ndests; ++j) | |
3767 | re_node_set_free (dests_node + j); | |
3768 | return REG_MISSING; | |
3769 | } | |
3770 | ||
3771 | #ifdef RE_ENABLE_I18N | |
3772 | /* Check how many bytes the node 'dfa->nodes[node_idx]' accepts. | |
3773 | Return the number of the bytes the node accepts. | |
3774 | STR_IDX is the current index of the input string. | |
3775 | ||
3776 | This function handles the nodes which can accept one character, or | |
3777 | one collating element like '.', '[a-z]', opposite to the other nodes | |
3778 | can only accept one byte. */ | |
3779 | ||
3780 | static int | |
3781 | internal_function | |
3782 | check_node_accept_bytes (const re_dfa_t *dfa, Idx node_idx, | |
3783 | const re_string_t *input, Idx str_idx) | |
3784 | { | |
3785 | const re_token_t *node = dfa->nodes + node_idx; | |
3786 | int char_len, elem_len; | |
3787 | Idx i; | |
3788 | ||
3789 | if (BE (node->type == OP_UTF8_PERIOD, 0)) | |
3790 | { | |
3791 | unsigned char c = re_string_byte_at (input, str_idx), d; | |
3792 | if (BE (c < 0xc2, 1)) | |
3793 | return 0; | |
3794 | ||
3795 | if (str_idx + 2 > input->len) | |
3796 | return 0; | |
3797 | ||
3798 | d = re_string_byte_at (input, str_idx + 1); | |
3799 | if (c < 0xe0) | |
3800 | return (d < 0x80 || d > 0xbf) ? 0 : 2; | |
3801 | else if (c < 0xf0) | |
3802 | { | |
3803 | char_len = 3; | |
3804 | if (c == 0xe0 && d < 0xa0) | |
3805 | return 0; | |
3806 | } | |
3807 | else if (c < 0xf8) | |
3808 | { | |
3809 | char_len = 4; | |
3810 | if (c == 0xf0 && d < 0x90) | |
3811 | return 0; | |
3812 | } | |
3813 | else if (c < 0xfc) | |
3814 | { | |
3815 | char_len = 5; | |
3816 | if (c == 0xf8 && d < 0x88) | |
3817 | return 0; | |
3818 | } | |
3819 | else if (c < 0xfe) | |
3820 | { | |
3821 | char_len = 6; | |
3822 | if (c == 0xfc && d < 0x84) | |
3823 | return 0; | |
3824 | } | |
3825 | else | |
3826 | return 0; | |
3827 | ||
3828 | if (str_idx + char_len > input->len) | |
3829 | return 0; | |
3830 | ||
3831 | for (i = 1; i < char_len; ++i) | |
3832 | { | |
3833 | d = re_string_byte_at (input, str_idx + i); | |
3834 | if (d < 0x80 || d > 0xbf) | |
3835 | return 0; | |
3836 | } | |
3837 | return char_len; | |
3838 | } | |
3839 | ||
3840 | char_len = re_string_char_size_at (input, str_idx); | |
3841 | if (node->type == OP_PERIOD) | |
3842 | { | |
3843 | if (char_len <= 1) | |
3844 | return 0; | |
3845 | /* FIXME: I don't think this if is needed, as both '\n' | |
3846 | and '\0' are char_len == 1. */ | |
3847 | /* '.' accepts any one character except the following two cases. */ | |
3848 | if ((!(dfa->syntax & RE_DOT_NEWLINE) && | |
3849 | re_string_byte_at (input, str_idx) == '\n') || | |
3850 | ((dfa->syntax & RE_DOT_NOT_NULL) && | |
3851 | re_string_byte_at (input, str_idx) == '\0')) | |
3852 | return 0; | |
3853 | return char_len; | |
3854 | } | |
3855 | ||
3856 | elem_len = re_string_elem_size_at (input, str_idx); | |
3857 | if ((elem_len <= 1 && char_len <= 1) || char_len == 0) | |
3858 | return 0; | |
3859 | ||
3860 | if (node->type == COMPLEX_BRACKET) | |
3861 | { | |
3862 | const re_charset_t *cset = node->opr.mbcset; | |
3863 | # ifdef _LIBC | |
3864 | const unsigned char *pin | |
3865 | = ((const unsigned char *) re_string_get_buffer (input) + str_idx); | |
3866 | Idx j; | |
3867 | uint32_t nrules; | |
3868 | # endif /* _LIBC */ | |
3869 | int match_len = 0; | |
3870 | wchar_t wc = ((cset->nranges || cset->nchar_classes || cset->nmbchars) | |
3871 | ? re_string_wchar_at (input, str_idx) : 0); | |
3872 | ||
3873 | /* match with multibyte character? */ | |
3874 | for (i = 0; i < cset->nmbchars; ++i) | |
3875 | if (wc == cset->mbchars[i]) | |
3876 | { | |
3877 | match_len = char_len; | |
3878 | goto check_node_accept_bytes_match; | |
3879 | } | |
3880 | /* match with character_class? */ | |
3881 | for (i = 0; i < cset->nchar_classes; ++i) | |
3882 | { | |
3883 | wctype_t wt = cset->char_classes[i]; | |
3884 | if (__iswctype (wc, wt)) | |
3885 | { | |
3886 | match_len = char_len; | |
3887 | goto check_node_accept_bytes_match; | |
3888 | } | |
3889 | } | |
3890 | ||
3891 | # ifdef _LIBC | |
3892 | nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES); | |
3893 | if (nrules != 0) | |
3894 | { | |
3895 | unsigned int in_collseq = 0; | |
3896 | const int32_t *table, *indirect; | |
3897 | const unsigned char *weights, *extra; | |
3898 | const char *collseqwc; | |
3899 | int32_t idx; | |
3900 | /* This #include defines a local function! */ | |
3901 | # include <locale/weight.h> | |
3902 | ||
3903 | /* match with collating_symbol? */ | |
3904 | if (cset->ncoll_syms) | |
3905 | extra = (const unsigned char *) | |
3906 | _NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB); | |
3907 | for (i = 0; i < cset->ncoll_syms; ++i) | |
3908 | { | |
3909 | const unsigned char *coll_sym = extra + cset->coll_syms[i]; | |
3910 | /* Compare the length of input collating element and | |
3911 | the length of current collating element. */ | |
3912 | if (*coll_sym != elem_len) | |
3913 | continue; | |
3914 | /* Compare each bytes. */ | |
3915 | for (j = 0; j < *coll_sym; j++) | |
3916 | if (pin[j] != coll_sym[1 + j]) | |
3917 | break; | |
3918 | if (j == *coll_sym) | |
3919 | { | |
3920 | /* Match if every bytes is equal. */ | |
3921 | match_len = j; | |
3922 | goto check_node_accept_bytes_match; | |
3923 | } | |
3924 | } | |
3925 | ||
3926 | if (cset->nranges) | |
3927 | { | |
3928 | if (elem_len <= char_len) | |
3929 | { | |
3930 | collseqwc = _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQWC); | |
3931 | in_collseq = __collseq_table_lookup (collseqwc, wc); | |
3932 | } | |
3933 | else | |
3934 | in_collseq = find_collation_sequence_value (pin, elem_len); | |
3935 | } | |
3936 | /* match with range expression? */ | |
3937 | for (i = 0; i < cset->nranges; ++i) | |
3938 | if (cset->range_starts[i] <= in_collseq | |
3939 | && in_collseq <= cset->range_ends[i]) | |
3940 | { | |
3941 | match_len = elem_len; | |
3942 | goto check_node_accept_bytes_match; | |
3943 | } | |
3944 | ||
3945 | /* match with equivalence_class? */ | |
3946 | if (cset->nequiv_classes) | |
3947 | { | |
3948 | const unsigned char *cp = pin; | |
3949 | table = (const int32_t *) | |
3950 | _NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB); | |
3951 | weights = (const unsigned char *) | |
3952 | _NL_CURRENT (LC_COLLATE, _NL_COLLATE_WEIGHTMB); | |
3953 | extra = (const unsigned char *) | |
3954 | _NL_CURRENT (LC_COLLATE, _NL_COLLATE_EXTRAMB); | |
3955 | indirect = (const int32_t *) | |
3956 | _NL_CURRENT (LC_COLLATE, _NL_COLLATE_INDIRECTMB); | |
3957 | int32_t idx = findidx (&cp); | |
3958 | if (idx > 0) | |
3959 | for (i = 0; i < cset->nequiv_classes; ++i) | |
3960 | { | |
3961 | int32_t equiv_class_idx = cset->equiv_classes[i]; | |
3962 | size_t weight_len = weights[idx & 0xffffff]; | |
3963 | if (weight_len == weights[equiv_class_idx & 0xffffff] | |
3964 | && (idx >> 24) == (equiv_class_idx >> 24)) | |
3965 | { | |
3966 | Idx cnt = 0; | |
3967 | ||
3968 | idx &= 0xffffff; | |
3969 | equiv_class_idx &= 0xffffff; | |
3970 | ||
3971 | while (cnt <= weight_len | |
3972 | && (weights[equiv_class_idx + 1 + cnt] | |
3973 | == weights[idx + 1 + cnt])) | |
3974 | ++cnt; | |
3975 | if (cnt > weight_len) | |
3976 | { | |
3977 | match_len = elem_len; | |
3978 | goto check_node_accept_bytes_match; | |
3979 | } | |
3980 | } | |
3981 | } | |
3982 | } | |
3983 | } | |
3984 | else | |
3985 | # endif /* _LIBC */ | |
3986 | { | |
3987 | /* match with range expression? */ | |
3988 | #if __GNUC__ >= 2 && ! (__STDC_VERSION__ < 199901L && defined __STRICT_ANSI__) | |
3989 | wchar_t cmp_buf[] = {L'\0', L'\0', wc, L'\0', L'\0', L'\0'}; | |
3990 | #else | |
3991 | wchar_t cmp_buf[] = {L'\0', L'\0', L'\0', L'\0', L'\0', L'\0'}; | |
3992 | cmp_buf[2] = wc; | |
3993 | #endif | |
3994 | for (i = 0; i < cset->nranges; ++i) | |
3995 | { | |
3996 | cmp_buf[0] = cset->range_starts[i]; | |
3997 | cmp_buf[4] = cset->range_ends[i]; | |
3998 | if (wcscoll (cmp_buf, cmp_buf + 2) <= 0 | |
3999 | && wcscoll (cmp_buf + 2, cmp_buf + 4) <= 0) | |
4000 | { | |
4001 | match_len = char_len; | |
4002 | goto check_node_accept_bytes_match; | |
4003 | } | |
4004 | } | |
4005 | } | |
4006 | check_node_accept_bytes_match: | |
4007 | if (!cset->non_match) | |
4008 | return match_len; | |
4009 | else | |
4010 | { | |
4011 | if (match_len > 0) | |
4012 | return 0; | |
4013 | else | |
4014 | return (elem_len > char_len) ? elem_len : char_len; | |
4015 | } | |
4016 | } | |
4017 | return 0; | |
4018 | } | |
4019 | ||
4020 | # ifdef _LIBC | |
4021 | static unsigned int | |
4022 | internal_function | |
4023 | find_collation_sequence_value (const unsigned char *mbs, size_t mbs_len) | |
4024 | { | |
4025 | uint32_t nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES); | |
4026 | if (nrules == 0) | |
4027 | { | |
4028 | if (mbs_len == 1) | |
4029 | { | |
4030 | /* No valid character. Match it as a single byte character. */ | |
4031 | const unsigned char *collseq = (const unsigned char *) | |
4032 | _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQMB); | |
4033 | return collseq[mbs[0]]; | |
4034 | } | |
4035 | return UINT_MAX; | |
4036 | } | |
4037 | else | |
4038 | { | |
4039 | int32_t idx; | |
4040 | const unsigned char *extra = (const unsigned char *) | |
4041 | _NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB); | |
4042 | int32_t extrasize = (const unsigned char *) | |
4043 | _NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB + 1) - extra; | |
4044 | ||
4045 | for (idx = 0; idx < extrasize;) | |
4046 | { | |
4047 | int mbs_cnt; | |
4048 | bool found = false; | |
4049 | int32_t elem_mbs_len; | |
4050 | /* Skip the name of collating element name. */ | |
4051 | idx = idx + extra[idx] + 1; | |
4052 | elem_mbs_len = extra[idx++]; | |
4053 | if (mbs_len == elem_mbs_len) | |
4054 | { | |
4055 | for (mbs_cnt = 0; mbs_cnt < elem_mbs_len; ++mbs_cnt) | |
4056 | if (extra[idx + mbs_cnt] != mbs[mbs_cnt]) | |
4057 | break; | |
4058 | if (mbs_cnt == elem_mbs_len) | |
4059 | /* Found the entry. */ | |
4060 | found = true; | |
4061 | } | |
4062 | /* Skip the byte sequence of the collating element. */ | |
4063 | idx += elem_mbs_len; | |
4064 | /* Adjust for the alignment. */ | |
4065 | idx = (idx + 3) & ~3; | |
4066 | /* Skip the collation sequence value. */ | |
4067 | idx += sizeof (uint32_t); | |
4068 | /* Skip the wide char sequence of the collating element. */ | |
4069 | idx = idx + sizeof (uint32_t) * (extra[idx] + 1); | |
4070 | /* If we found the entry, return the sequence value. */ | |
4071 | if (found) | |
4072 | return *(uint32_t *) (extra + idx); | |
4073 | /* Skip the collation sequence value. */ | |
4074 | idx += sizeof (uint32_t); | |
4075 | } | |
4076 | return UINT_MAX; | |
4077 | } | |
4078 | } | |
4079 | # endif /* _LIBC */ | |
4080 | #endif /* RE_ENABLE_I18N */ | |
4081 | ||
4082 | /* Check whether the node accepts the byte which is IDX-th | |
4083 | byte of the INPUT. */ | |
4084 | ||
4085 | static bool | |
4086 | internal_function | |
4087 | check_node_accept (const re_match_context_t *mctx, const re_token_t *node, | |
4088 | Idx idx) | |
4089 | { | |
4090 | unsigned char ch; | |
4091 | ch = re_string_byte_at (&mctx->input, idx); | |
4092 | switch (node->type) | |
4093 | { | |
4094 | case CHARACTER: | |
4095 | if (node->opr.c != ch) | |
4096 | return false; | |
4097 | break; | |
4098 | ||
4099 | case SIMPLE_BRACKET: | |
4100 | if (!bitset_contain (node->opr.sbcset, ch)) | |
4101 | return false; | |
4102 | break; | |
4103 | ||
4104 | #ifdef RE_ENABLE_I18N | |
4105 | case OP_UTF8_PERIOD: | |
4106 | if (ch >= ASCII_CHARS) | |
4107 | return false; | |
4108 | /* FALLTHROUGH */ | |
4109 | #endif | |
4110 | case OP_PERIOD: | |
4111 | if ((ch == '\n' && !(mctx->dfa->syntax & RE_DOT_NEWLINE)) | |
4112 | || (ch == '\0' && (mctx->dfa->syntax & RE_DOT_NOT_NULL))) | |
4113 | return false; | |
4114 | break; | |
4115 | ||
4116 | default: | |
4117 | return false; | |
4118 | } | |
4119 | ||
4120 | if (node->constraint) | |
4121 | { | |
4122 | /* The node has constraints. Check whether the current context | |
4123 | satisfies the constraints. */ | |
4124 | unsigned int context = re_string_context_at (&mctx->input, idx, | |
4125 | mctx->eflags); | |
4126 | if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context)) | |
4127 | return false; | |
4128 | } | |
4129 | ||
4130 | return true; | |
4131 | } | |
4132 | ||
4133 | /* Extend the buffers, if the buffers have run out. */ | |
4134 | ||
4135 | static reg_errcode_t | |
4136 | internal_function __attribute_warn_unused_result__ | |
4137 | extend_buffers (re_match_context_t *mctx) | |
4138 | { | |
4139 | reg_errcode_t ret; | |
4140 | re_string_t *pstr = &mctx->input; | |
4141 | ||
4142 | /* Avoid overflow. */ | |
4143 | if (BE (SIZE_MAX / 2 / sizeof (re_dfastate_t *) <= pstr->bufs_len, 0)) | |
4144 | return REG_ESPACE; | |
4145 | ||
4146 | /* Double the lengthes of the buffers. */ | |
4147 | ret = re_string_realloc_buffers (pstr, pstr->bufs_len * 2); | |
4148 | if (BE (ret != REG_NOERROR, 0)) | |
4149 | return ret; | |
4150 | ||
4151 | if (mctx->state_log != NULL) | |
4152 | { | |
4153 | /* And double the length of state_log. */ | |
4154 | /* XXX We have no indication of the size of this buffer. If this | |
4155 | allocation fail we have no indication that the state_log array | |
4156 | does not have the right size. */ | |
4157 | re_dfastate_t **new_array = re_realloc (mctx->state_log, re_dfastate_t *, | |
4158 | pstr->bufs_len + 1); | |
4159 | if (BE (new_array == NULL, 0)) | |
4160 | return REG_ESPACE; | |
4161 | mctx->state_log = new_array; | |
4162 | } | |
4163 | ||
4164 | /* Then reconstruct the buffers. */ | |
4165 | if (pstr->icase) | |
4166 | { | |
4167 | #ifdef RE_ENABLE_I18N | |
4168 | if (pstr->mb_cur_max > 1) | |
4169 | { | |
4170 | ret = build_wcs_upper_buffer (pstr); | |
4171 | if (BE (ret != REG_NOERROR, 0)) | |
4172 | return ret; | |
4173 | } | |
4174 | else | |
4175 | #endif /* RE_ENABLE_I18N */ | |
4176 | build_upper_buffer (pstr); | |
4177 | } | |
4178 | else | |
4179 | { | |
4180 | #ifdef RE_ENABLE_I18N | |
4181 | if (pstr->mb_cur_max > 1) | |
4182 | build_wcs_buffer (pstr); | |
4183 | else | |
4184 | #endif /* RE_ENABLE_I18N */ | |
4185 | { | |
4186 | if (pstr->trans != NULL) | |
4187 | re_string_translate_buffer (pstr); | |
4188 | } | |
4189 | } | |
4190 | return REG_NOERROR; | |
4191 | } | |
4192 | ||
4193 | \f | |
4194 | /* Functions for matching context. */ | |
4195 | ||
4196 | /* Initialize MCTX. */ | |
4197 | ||
4198 | static reg_errcode_t | |
4199 | internal_function __attribute_warn_unused_result__ | |
4200 | match_ctx_init (re_match_context_t *mctx, int eflags, Idx n) | |
4201 | { | |
4202 | mctx->eflags = eflags; | |
4203 | mctx->match_last = REG_MISSING; | |
4204 | if (n > 0) | |
4205 | { | |
4206 | /* Avoid overflow. */ | |
4207 | size_t max_object_size = | |
4208 | MAX (sizeof (struct re_backref_cache_entry), | |
4209 | sizeof (re_sub_match_top_t *)); | |
4210 | if (BE (SIZE_MAX / max_object_size < n, 0)) | |
4211 | return REG_ESPACE; | |
4212 | ||
4213 | mctx->bkref_ents = re_malloc (struct re_backref_cache_entry, n); | |
4214 | mctx->sub_tops = re_malloc (re_sub_match_top_t *, n); | |
4215 | if (BE (mctx->bkref_ents == NULL || mctx->sub_tops == NULL, 0)) | |
4216 | return REG_ESPACE; | |
4217 | } | |
4218 | /* Already zero-ed by the caller. | |
4219 | else | |
4220 | mctx->bkref_ents = NULL; | |
4221 | mctx->nbkref_ents = 0; | |
4222 | mctx->nsub_tops = 0; */ | |
4223 | mctx->abkref_ents = n; | |
4224 | mctx->max_mb_elem_len = 1; | |
4225 | mctx->asub_tops = n; | |
4226 | return REG_NOERROR; | |
4227 | } | |
4228 | ||
4229 | /* Clean the entries which depend on the current input in MCTX. | |
4230 | This function must be invoked when the matcher changes the start index | |
4231 | of the input, or changes the input string. */ | |
4232 | ||
4233 | static void | |
4234 | internal_function | |
4235 | match_ctx_clean (re_match_context_t *mctx) | |
4236 | { | |
4237 | Idx st_idx; | |
4238 | for (st_idx = 0; st_idx < mctx->nsub_tops; ++st_idx) | |
4239 | { | |
4240 | Idx sl_idx; | |
4241 | re_sub_match_top_t *top = mctx->sub_tops[st_idx]; | |
4242 | for (sl_idx = 0; sl_idx < top->nlasts; ++sl_idx) | |
4243 | { | |
4244 | re_sub_match_last_t *last = top->lasts[sl_idx]; | |
4245 | re_free (last->path.array); | |
4246 | re_free (last); | |
4247 | } | |
4248 | re_free (top->lasts); | |
4249 | if (top->path) | |
4250 | { | |
4251 | re_free (top->path->array); | |
4252 | re_free (top->path); | |
4253 | } | |
4254 | free (top); | |
4255 | } | |
4256 | ||
4257 | mctx->nsub_tops = 0; | |
4258 | mctx->nbkref_ents = 0; | |
4259 | } | |
4260 | ||
4261 | /* Free all the memory associated with MCTX. */ | |
4262 | ||
4263 | static void | |
4264 | internal_function | |
4265 | match_ctx_free (re_match_context_t *mctx) | |
4266 | { | |
4267 | /* First, free all the memory associated with MCTX->SUB_TOPS. */ | |
4268 | match_ctx_clean (mctx); | |
4269 | re_free (mctx->sub_tops); | |
4270 | re_free (mctx->bkref_ents); | |
4271 | } | |
4272 | ||
4273 | /* Add a new backreference entry to MCTX. | |
4274 | Note that we assume that caller never call this function with duplicate | |
4275 | entry, and call with STR_IDX which isn't smaller than any existing entry. | |
4276 | */ | |
4277 | ||
4278 | static reg_errcode_t | |
4279 | internal_function __attribute_warn_unused_result__ | |
4280 | match_ctx_add_entry (re_match_context_t *mctx, Idx node, Idx str_idx, Idx from, | |
4281 | Idx to) | |
4282 | { | |
4283 | if (mctx->nbkref_ents >= mctx->abkref_ents) | |
4284 | { | |
4285 | struct re_backref_cache_entry* new_entry; | |
4286 | new_entry = re_realloc (mctx->bkref_ents, struct re_backref_cache_entry, | |
4287 | mctx->abkref_ents * 2); | |
4288 | if (BE (new_entry == NULL, 0)) | |
4289 | { | |
4290 | re_free (mctx->bkref_ents); | |
4291 | return REG_ESPACE; | |
4292 | } | |
4293 | mctx->bkref_ents = new_entry; | |
4294 | memset (mctx->bkref_ents + mctx->nbkref_ents, '\0', | |
4295 | sizeof (struct re_backref_cache_entry) * mctx->abkref_ents); | |
4296 | mctx->abkref_ents *= 2; | |
4297 | } | |
4298 | if (mctx->nbkref_ents > 0 | |
4299 | && mctx->bkref_ents[mctx->nbkref_ents - 1].str_idx == str_idx) | |
4300 | mctx->bkref_ents[mctx->nbkref_ents - 1].more = 1; | |
4301 | ||
4302 | mctx->bkref_ents[mctx->nbkref_ents].node = node; | |
4303 | mctx->bkref_ents[mctx->nbkref_ents].str_idx = str_idx; | |
4304 | mctx->bkref_ents[mctx->nbkref_ents].subexp_from = from; | |
4305 | mctx->bkref_ents[mctx->nbkref_ents].subexp_to = to; | |
4306 | ||
4307 | /* This is a cache that saves negative results of check_dst_limits_calc_pos. | |
4308 | If bit N is clear, means that this entry won't epsilon-transition to | |
4309 | an OP_OPEN_SUBEXP or OP_CLOSE_SUBEXP for the N+1-th subexpression. If | |
4310 | it is set, check_dst_limits_calc_pos_1 will recurse and try to find one | |
4311 | such node. | |
4312 | ||
4313 | A backreference does not epsilon-transition unless it is empty, so set | |
4314 | to all zeros if FROM != TO. */ | |
4315 | mctx->bkref_ents[mctx->nbkref_ents].eps_reachable_subexps_map | |
4316 | = (from == to ? -1 : 0); | |
4317 | ||
4318 | mctx->bkref_ents[mctx->nbkref_ents++].more = 0; | |
4319 | if (mctx->max_mb_elem_len < to - from) | |
4320 | mctx->max_mb_elem_len = to - from; | |
4321 | return REG_NOERROR; | |
4322 | } | |
4323 | ||
4324 | /* Return the first entry with the same str_idx, or REG_MISSING if none is | |
4325 | found. Note that MCTX->BKREF_ENTS is already sorted by MCTX->STR_IDX. */ | |
4326 | ||
4327 | static Idx | |
4328 | internal_function | |
4329 | search_cur_bkref_entry (const re_match_context_t *mctx, Idx str_idx) | |
4330 | { | |
4331 | Idx left, right, mid, last; | |
4332 | last = right = mctx->nbkref_ents; | |
4333 | for (left = 0; left < right;) | |
4334 | { | |
4335 | mid = (left + right) / 2; | |
4336 | if (mctx->bkref_ents[mid].str_idx < str_idx) | |
4337 | left = mid + 1; | |
4338 | else | |
4339 | right = mid; | |
4340 | } | |
4341 | if (left < last && mctx->bkref_ents[left].str_idx == str_idx) | |
4342 | return left; | |
4343 | else | |
4344 | return REG_MISSING; | |
4345 | } | |
4346 | ||
4347 | /* Register the node NODE, whose type is OP_OPEN_SUBEXP, and which matches | |
4348 | at STR_IDX. */ | |
4349 | ||
4350 | static reg_errcode_t | |
4351 | internal_function __attribute_warn_unused_result__ | |
4352 | match_ctx_add_subtop (re_match_context_t *mctx, Idx node, Idx str_idx) | |
4353 | { | |
4354 | #ifdef DEBUG | |
4355 | assert (mctx->sub_tops != NULL); | |
4356 | assert (mctx->asub_tops > 0); | |
4357 | #endif | |
4358 | if (BE (mctx->nsub_tops == mctx->asub_tops, 0)) | |
4359 | { | |
4360 | Idx new_asub_tops = mctx->asub_tops * 2; | |
4361 | re_sub_match_top_t **new_array = re_realloc (mctx->sub_tops, | |
4362 | re_sub_match_top_t *, | |
4363 | new_asub_tops); | |
4364 | if (BE (new_array == NULL, 0)) | |
4365 | return REG_ESPACE; | |
4366 | mctx->sub_tops = new_array; | |
4367 | mctx->asub_tops = new_asub_tops; | |
4368 | } | |
4369 | mctx->sub_tops[mctx->nsub_tops] = calloc (1, sizeof (re_sub_match_top_t)); | |
4370 | if (BE (mctx->sub_tops[mctx->nsub_tops] == NULL, 0)) | |
4371 | return REG_ESPACE; | |
4372 | mctx->sub_tops[mctx->nsub_tops]->node = node; | |
4373 | mctx->sub_tops[mctx->nsub_tops++]->str_idx = str_idx; | |
4374 | return REG_NOERROR; | |
4375 | } | |
4376 | ||
4377 | /* Register the node NODE, whose type is OP_CLOSE_SUBEXP, and which matches | |
4378 | at STR_IDX, whose corresponding OP_OPEN_SUBEXP is SUB_TOP. */ | |
4379 | ||
4380 | static re_sub_match_last_t * | |
4381 | internal_function | |
4382 | match_ctx_add_sublast (re_sub_match_top_t *subtop, Idx node, Idx str_idx) | |
4383 | { | |
4384 | re_sub_match_last_t *new_entry; | |
4385 | if (BE (subtop->nlasts == subtop->alasts, 0)) | |
4386 | { | |
4387 | Idx new_alasts = 2 * subtop->alasts + 1; | |
4388 | re_sub_match_last_t **new_array = re_realloc (subtop->lasts, | |
4389 | re_sub_match_last_t *, | |
4390 | new_alasts); | |
4391 | if (BE (new_array == NULL, 0)) | |
4392 | return NULL; | |
4393 | subtop->lasts = new_array; | |
4394 | subtop->alasts = new_alasts; | |
4395 | } | |
4396 | new_entry = calloc (1, sizeof (re_sub_match_last_t)); | |
4397 | if (BE (new_entry != NULL, 1)) | |
4398 | { | |
4399 | subtop->lasts[subtop->nlasts] = new_entry; | |
4400 | new_entry->node = node; | |
4401 | new_entry->str_idx = str_idx; | |
4402 | ++subtop->nlasts; | |
4403 | } | |
4404 | return new_entry; | |
4405 | } | |
4406 | ||
4407 | static void | |
4408 | internal_function | |
4409 | sift_ctx_init (re_sift_context_t *sctx, re_dfastate_t **sifted_sts, | |
4410 | re_dfastate_t **limited_sts, Idx last_node, Idx last_str_idx) | |
4411 | { | |
4412 | sctx->sifted_states = sifted_sts; | |
4413 | sctx->limited_states = limited_sts; | |
4414 | sctx->last_node = last_node; | |
4415 | sctx->last_str_idx = last_str_idx; | |
4416 | re_node_set_init_empty (&sctx->limits); | |
4417 | } |