-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathregexec.c
3983 lines (3711 loc) · 118 KB
/
regexec.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/* Extended regular expression matching and search library.
Copyright (C) 2002, 2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
static reg_errcode_t match_ctx_init _RE_ARGS((re_match_context_t *cache, int eflags,
re_string_t *input, int n));
static void match_ctx_clean _RE_ARGS((re_match_context_t *mctx));
static void match_ctx_free _RE_ARGS((re_match_context_t *cache));
static void match_ctx_free_subtops _RE_ARGS((re_match_context_t *mctx));
static reg_errcode_t match_ctx_add_entry _RE_ARGS((re_match_context_t *cache, int node,
int str_idx, int from, int to));
static int search_cur_bkref_entry _RE_ARGS((re_match_context_t *mctx, int str_idx));
static void match_ctx_clear_flag _RE_ARGS((re_match_context_t *mctx));
static reg_errcode_t match_ctx_add_subtop _RE_ARGS((re_match_context_t *mctx, int node,
int str_idx));
static re_sub_match_last_t * match_ctx_add_sublast _RE_ARGS((re_sub_match_top_t *subtop,
int node, int str_idx));
static void sift_ctx_init _RE_ARGS((re_sift_context_t *sctx, re_dfastate_t **sifted_sts,
re_dfastate_t **limited_sts, int last_node,
int last_str_idx, int check_subexp));
static reg_errcode_t re_search_internal _RE_ARGS((const regex_t *preg,
const char *string, int length,
int start, int range, int stop,
size_t nmatch, regmatch_t pmatch[],
int eflags));
static int re_search_2_stub _RE_ARGS((struct re_pattern_buffer *bufp,
const char *string1, int length1,
const char *string2, int length2,
int start, int range, struct re_registers *regs,
int stop, int ret_len));
static int re_search_stub _RE_ARGS((struct re_pattern_buffer *bufp,
const char *string, int length, int start,
int range, int stop, struct re_registers *regs,
int ret_len));
static unsigned re_copy_regs _RE_ARGS((struct re_registers *regs, regmatch_t *pmatch,
int nregs, int regs_allocated));
static inline re_dfastate_t *acquire_init_state_context _RE_ARGS((reg_errcode_t *err,
const regex_t *preg,
const re_match_context_t *mctx,
int idx));
static reg_errcode_t prune_impossible_nodes _RE_ARGS((const regex_t *preg,
re_match_context_t *mctx));
static int check_matching _RE_ARGS((const regex_t *preg, re_match_context_t *mctx,
int fl_search, int fl_longest_match));
static int check_halt_node_context _RE_ARGS((const re_dfa_t *dfa, int node,
unsigned int context));
static int check_halt_state_context _RE_ARGS((const regex_t *preg,
const re_dfastate_t *state,
const re_match_context_t *mctx, int idx));
static void update_regs _RE_ARGS((re_dfa_t *dfa, regmatch_t *pmatch, int cur_node,
int cur_idx, int nmatch));
static int proceed_next_node _RE_ARGS((const regex_t *preg, int nregs, regmatch_t *regs,
const re_match_context_t *mctx,
int *pidx, int node, re_node_set *eps_via_nodes,
struct re_fail_stack_t *fs));
static reg_errcode_t push_fail_stack _RE_ARGS((struct re_fail_stack_t *fs,
int str_idx, int *dests, int nregs,
regmatch_t *regs,
re_node_set *eps_via_nodes));
static int pop_fail_stack _RE_ARGS((struct re_fail_stack_t *fs, int *pidx, int nregs,
regmatch_t *regs, re_node_set *eps_via_nodes));
static reg_errcode_t set_regs _RE_ARGS((const regex_t *preg,
const re_match_context_t *mctx,
size_t nmatch, regmatch_t *pmatch,
int fl_backtrack));
static reg_errcode_t free_fail_stack_return _RE_ARGS((struct re_fail_stack_t *fs));
#ifdef RE_ENABLE_I18N
static int sift_states_iter_mb _RE_ARGS((const regex_t *preg,
const re_match_context_t *mctx,
re_sift_context_t *sctx,
int node_idx, int str_idx, int max_str_idx));
#endif /* RE_ENABLE_I18N */
static reg_errcode_t sift_states_backward _RE_ARGS((const regex_t *preg,
re_match_context_t *mctx,
re_sift_context_t *sctx));
static reg_errcode_t update_cur_sifted_state _RE_ARGS((const regex_t *preg,
re_match_context_t *mctx,
re_sift_context_t *sctx,
int str_idx,
re_node_set *dest_nodes));
static reg_errcode_t add_epsilon_src_nodes _RE_ARGS((re_dfa_t *dfa,
re_node_set *dest_nodes,
const re_node_set *candidates));
static reg_errcode_t sub_epsilon_src_nodes _RE_ARGS((re_dfa_t *dfa, int node,
re_node_set *dest_nodes,
const re_node_set *and_nodes));
static int check_dst_limits _RE_ARGS((re_dfa_t *dfa, re_node_set *limits,
re_match_context_t *mctx, int dst_node,
int dst_idx, int src_node, int src_idx));
static int check_dst_limits_calc_pos _RE_ARGS((re_dfa_t *dfa, re_match_context_t *mctx,
int limit, re_node_set *eclosures,
int subexp_idx, int node, int str_idx));
static reg_errcode_t check_subexp_limits _RE_ARGS((re_dfa_t *dfa,
re_node_set *dest_nodes,
const re_node_set *candidates,
re_node_set *limits,
struct re_backref_cache_entry *bkref_ents,
int str_idx));
static reg_errcode_t sift_states_bkref _RE_ARGS((const regex_t *preg,
re_match_context_t *mctx,
re_sift_context_t *sctx,
int str_idx, re_node_set *dest_nodes));
static reg_errcode_t clean_state_log_if_need _RE_ARGS((re_match_context_t *mctx,
int next_state_log_idx));
static reg_errcode_t merge_state_array _RE_ARGS((re_dfa_t *dfa, re_dfastate_t **dst,
re_dfastate_t **src, int num));
static re_dfastate_t *transit_state _RE_ARGS((reg_errcode_t *err, const regex_t *preg,
re_match_context_t *mctx,
re_dfastate_t *state, int fl_search));
static reg_errcode_t check_subexp_matching_top _RE_ARGS((re_dfa_t *dfa,
re_match_context_t *mctx,
re_node_set *cur_nodes,
int str_idx));
static re_dfastate_t *transit_state_sb _RE_ARGS((reg_errcode_t *err, const regex_t *preg,
re_dfastate_t *pstate,
int fl_search,
re_match_context_t *mctx));
#ifdef RE_ENABLE_I18N
static reg_errcode_t transit_state_mb _RE_ARGS((const regex_t *preg,
re_dfastate_t *pstate,
re_match_context_t *mctx));
#endif /* RE_ENABLE_I18N */
static reg_errcode_t transit_state_bkref _RE_ARGS((const regex_t *preg,
re_node_set *nodes,
re_match_context_t *mctx));
static reg_errcode_t get_subexp _RE_ARGS((const regex_t *preg, re_match_context_t *mctx,
int bkref_node, int bkref_str_idx));
static reg_errcode_t get_subexp_sub _RE_ARGS((const regex_t *preg,
re_match_context_t *mctx,
re_sub_match_top_t *sub_top,
re_sub_match_last_t *sub_last,
int bkref_node, int bkref_str));
static int find_subexp_node _RE_ARGS((re_dfa_t *dfa, re_node_set *nodes,
int subexp_idx, int fl_open));
static reg_errcode_t check_arrival _RE_ARGS((const regex_t *preg,
re_match_context_t *mctx,
state_array_t *path, int top_node,
int top_str, int last_node, int last_str,
int fl_open));
static reg_errcode_t check_arrival_add_next_nodes _RE_ARGS((const regex_t *preg,
re_dfa_t *dfa,
re_match_context_t *mctx,
int str_idx,
re_node_set *cur_nodes,
re_node_set *next_nodes));
static reg_errcode_t check_arrival_expand_ecl _RE_ARGS((re_dfa_t *dfa,
re_node_set *cur_nodes,
int ex_subexp, int fl_open));
static reg_errcode_t check_arrival_expand_ecl_sub _RE_ARGS((re_dfa_t *dfa,
re_node_set *dst_nodes,
int target, int ex_subexp,
int fl_open));
static reg_errcode_t expand_bkref_cache _RE_ARGS((const regex_t *preg,
re_match_context_t *mctx,
re_node_set *cur_nodes, int cur_str,
int last_str, int subexp_num,
int fl_open));
static re_dfastate_t **build_trtable _RE_ARGS((const regex_t *dfa,
const re_dfastate_t *state,
int fl_search));
#ifdef RE_ENABLE_I18N
static int check_node_accept_bytes _RE_ARGS((const regex_t *preg, int node_idx,
const re_string_t *input, int idx));
# ifdef _LIBC
static unsigned int find_collation_sequence_value _RE_ARGS((const unsigned char *mbs,
size_t name_len));
# endif /* _LIBC */
#endif /* RE_ENABLE_I18N */
static int group_nodes_into_DFAstates _RE_ARGS((const regex_t *dfa,
const re_dfastate_t *state,
re_node_set *states_node,
bitset *states_ch));
static int check_node_accept _RE_ARGS((const regex_t *preg, const re_token_t *node,
const re_match_context_t *mctx, int idx));
static reg_errcode_t extend_buffers _RE_ARGS((re_match_context_t *mctx));
/* Entry point for POSIX code. */
/* regexec searches for a given pattern, specified by PREG, in the
string STRING.
If NMATCH is zero or REG_NOSUB was set in the cflags argument to
`regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
least NMATCH elements, and we set them to the offsets of the
corresponding matched substrings.
EFLAGS specifies `execution flags' which affect matching: if
REG_NOTBOL is set, then ^ does not match at the beginning of the
string; if REG_NOTEOL is set, then $ does not match at the end.
We return 0 if we find a match and REG_NOMATCH if not. */
int
regexec (preg, string, nmatch, pmatch, eflags)
const regex_t *__restrict preg;
const char *__restrict string;
size_t nmatch;
regmatch_t pmatch[];
int eflags;
{
reg_errcode_t err;
int length = strlen (string);
if (preg->no_sub)
err = re_search_internal (preg, string, length, 0, length, length, 0,
NULL, eflags);
else
err = re_search_internal (preg, string, length, 0, length, length, nmatch,
pmatch, eflags);
return err != REG_NOERROR;
}
#ifdef _LIBC
weak_alias (__regexec, regexec)
#endif
/* Entry points for GNU code. */
/* re_match, re_search, re_match_2, re_search_2
The former two functions operate on STRING with length LENGTH,
while the later two operate on concatenation of STRING1 and STRING2
with lengths LENGTH1 and LENGTH2, respectively.
re_match() matches the compiled pattern in BUFP against the string,
starting at index START.
re_search() first tries matching at index START, then it tries to match
starting from index START + 1, and so on. The last start position tried
is START + RANGE. (Thus RANGE = 0 forces re_search to operate the same
way as re_match().)
The parameter STOP of re_{match,search}_2 specifies that no match exceeding
the first STOP characters of the concatenation of the strings should be
concerned.
If REGS is not NULL, and BUFP->no_sub is not set, the offsets of the match
and all groups is stroed in REGS. (For the "_2" variants, the offsets are
computed relative to the concatenation, not relative to the individual
strings.)
On success, re_match* functions return the length of the match, re_search*
return the position of the start of the match. Return value -1 means no
match was found and -2 indicates an internal error. */
int
re_match (bufp, string, length, start, regs)
struct re_pattern_buffer *bufp;
const char *string;
int length, start;
struct re_registers *regs;
{
return re_search_stub (bufp, string, length, start, 0, length, regs, 1);
}
#ifdef _LIBC
weak_alias (__re_match, re_match)
#endif
int
re_search (bufp, string, length, start, range, regs)
struct re_pattern_buffer *bufp;
const char *string;
int length, start, range;
struct re_registers *regs;
{
return re_search_stub (bufp, string, length, start, range, length, regs, 0);
}
#ifdef _LIBC
weak_alias (__re_search, re_search)
#endif
int
re_match_2 (bufp, string1, length1, string2, length2, start, regs, stop)
struct re_pattern_buffer *bufp;
const char *string1, *string2;
int length1, length2, start, stop;
struct re_registers *regs;
{
return re_search_2_stub (bufp, string1, length1, string2, length2,
start, 0, regs, stop, 1);
}
#ifdef _LIBC
weak_alias (__re_match_2, re_match_2)
#endif
int
re_search_2 (bufp, string1, length1, string2, length2, start, range, regs, stop)
struct re_pattern_buffer *bufp;
const char *string1, *string2;
int length1, length2, start, range, stop;
struct re_registers *regs;
{
return re_search_2_stub (bufp, string1, length1, string2, length2,
start, range, regs, stop, 0);
}
#ifdef _LIBC
weak_alias (__re_search_2, re_search_2)
#endif
static int
re_search_2_stub (bufp, string1, length1, string2, length2, start, range, regs,
stop, ret_len)
struct re_pattern_buffer *bufp;
const char *string1, *string2;
int length1, length2, start, range, stop, ret_len;
struct re_registers *regs;
{
const char *str;
int rval;
int len = length1 + length2;
int free_str = 0;
if (BE (length1 < 0 || length2 < 0 || stop < 0, 0))
return -2;
/* Concatenate the strings. */
if (length2 > 0)
if (length1 > 0)
{
char *s = re_malloc (char, len);
if (BE (s == NULL, 0))
return -2;
memcpy (s, string1, length1);
memcpy (s + length1, string2, length2);
str = s;
free_str = 1;
}
else
str = string2;
else
str = string1;
rval = re_search_stub (bufp, str, len, start, range, stop, regs,
ret_len);
if (free_str)
re_free ((char *) str);
return rval;
}
/* The parameters have the same meaning as those of re_search.
Additional parameters:
If RET_LEN is nonzero the length of the match is returned (re_match style);
otherwise the position of the match is returned. */
static int
re_search_stub (bufp, string, length, start, range, stop, regs, ret_len)
struct re_pattern_buffer *bufp;
const char *string;
int length, start, range, stop, ret_len;
struct re_registers *regs;
{
reg_errcode_t result;
regmatch_t *pmatch;
int nregs, rval;
int eflags = 0;
/* Check for out-of-range. */
if (BE (start < 0 || start > length, 0))
return -1;
if (BE (start + range > length, 0))
range = length - start;
else if (BE (start + range < 0, 0))
range = -start;
eflags |= (bufp->not_bol) ? REG_NOTBOL : 0;
eflags |= (bufp->not_eol) ? REG_NOTEOL : 0;
/* Compile fastmap if we haven't yet. */
if (range > 0 && bufp->fastmap != NULL && !bufp->fastmap_accurate)
re_compile_fastmap (bufp);
if (BE (bufp->no_sub, 0))
regs = NULL;
/* We need at least 1 register. */
if (regs == NULL)
nregs = 1;
else if (BE (bufp->regs_allocated == REGS_FIXED &&
regs->num_regs < bufp->re_nsub + 1, 0))
{
nregs = regs->num_regs;
if (BE (nregs < 1, 0))
{
/* Nothing can be copied to regs. */
regs = NULL;
nregs = 1;
}
}
else
nregs = bufp->re_nsub + 1;
pmatch = re_malloc (regmatch_t, nregs);
if (BE (pmatch == NULL, 0))
return -2;
result = re_search_internal (bufp, string, length, start, range, stop,
nregs, pmatch, eflags);
rval = 0;
/* I hope we needn't fill ther regs with -1's when no match was found. */
if (result != REG_NOERROR)
rval = -1;
else if (regs != NULL)
{
/* If caller wants register contents data back, copy them. */
bufp->regs_allocated = re_copy_regs (regs, pmatch, nregs,
bufp->regs_allocated);
if (BE (bufp->regs_allocated == REGS_UNALLOCATED, 0))
rval = -2;
}
if (BE (rval == 0, 1))
{
if (ret_len)
{
assert (pmatch[0].rm_so == start);
rval = pmatch[0].rm_eo - start;
}
else
rval = pmatch[0].rm_so;
}
re_free (pmatch);
return rval;
}
static unsigned
re_copy_regs (regs, pmatch, nregs, regs_allocated)
struct re_registers *regs;
regmatch_t *pmatch;
int nregs, regs_allocated;
{
int rval = REGS_REALLOCATE;
int i;
int need_regs = nregs + 1;
/* We need one extra element beyond `num_regs' for the `-1' marker GNU code
uses. */
/* Have the register data arrays been allocated? */
if (regs_allocated == REGS_UNALLOCATED)
{ /* No. So allocate them with malloc. */
regs->start = re_malloc (regoff_t, need_regs);
if (BE (regs->start == NULL, 0))
return REGS_UNALLOCATED;
regs->end = re_malloc (regoff_t, need_regs);
if (BE (regs->end == NULL, 0))
{
re_free (regs->start);
return REGS_UNALLOCATED;
}
regs->num_regs = need_regs;
}
else if (regs_allocated == REGS_REALLOCATE)
{ /* Yes. If we need more elements than were already
allocated, reallocate them. If we need fewer, just
leave it alone. */
if (need_regs > regs->num_regs)
{
regs->start = re_realloc (regs->start, regoff_t, need_regs);
if (BE (regs->start == NULL, 0))
{
if (regs->end != NULL)
re_free (regs->end);
return REGS_UNALLOCATED;
}
regs->end = re_realloc (regs->end, regoff_t, need_regs);
if (BE (regs->end == NULL, 0))
{
re_free (regs->start);
return REGS_UNALLOCATED;
}
regs->num_regs = need_regs;
}
}
else
{
assert (regs_allocated == REGS_FIXED);
/* This function may not be called with REGS_FIXED and nregs too big. */
assert (regs->num_regs >= nregs);
rval = REGS_FIXED;
}
/* Copy the regs. */
for (i = 0; i < nregs; ++i)
{
regs->start[i] = pmatch[i].rm_so;
regs->end[i] = pmatch[i].rm_eo;
}
for ( ; i < regs->num_regs; ++i)
regs->start[i] = regs->end[i] = -1;
return rval;
}
/* Set REGS to hold NUM_REGS registers, storing them in STARTS and
ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
this memory for recording register information. STARTS and ENDS
must be allocated using the malloc library routine, and must each
be at least NUM_REGS * sizeof (regoff_t) bytes long.
If NUM_REGS == 0, then subsequent matches should allocate their own
register data.
Unless this function is called, the first search or match using
PATTERN_BUFFER will allocate its own register data, without
freeing the old data. */
void
re_set_registers (bufp, regs, num_regs, starts, ends)
struct re_pattern_buffer *bufp;
struct re_registers *regs;
unsigned num_regs;
regoff_t *starts, *ends;
{
if (num_regs)
{
bufp->regs_allocated = REGS_REALLOCATE;
regs->num_regs = num_regs;
regs->start = starts;
regs->end = ends;
}
else
{
bufp->regs_allocated = REGS_UNALLOCATED;
regs->num_regs = 0;
regs->start = regs->end = (regoff_t *) 0;
}
}
#ifdef _LIBC
weak_alias (__re_set_registers, re_set_registers)
#endif
/* Entry points compatible with 4.2 BSD regex library. We don't define
them unless specifically requested. */
#if defined _REGEX_RE_COMP || defined _LIBC
int
# ifdef _LIBC
weak_function
# endif
re_exec (s)
const char *s;
{
return 0 == regexec (&re_comp_buf, s, 0, NULL, 0);
}
#endif /* _REGEX_RE_COMP */
static re_node_set empty_set;
/* Internal entry point. */
/* Searches for a compiled pattern PREG in the string STRING, whose
length is LENGTH. NMATCH, PMATCH, and EFLAGS have the same
mingings with regexec. START, and RANGE have the same meanings
with re_search.
Return REG_NOERROR if we find a match, and REG_NOMATCH if not,
otherwise return the error code.
Note: We assume front end functions already check ranges.
(START + RANGE >= 0 && START + RANGE <= LENGTH) */
static reg_errcode_t
re_search_internal (preg, string, length, start, range, stop, nmatch, pmatch,
eflags)
const regex_t *preg;
const char *string;
int length, start, range, stop, eflags;
size_t nmatch;
regmatch_t pmatch[];
{
reg_errcode_t err;
re_dfa_t *dfa = (re_dfa_t *)preg->buffer;
re_string_t input;
int left_lim, right_lim, incr;
int fl_longest_match, match_first, match_last = -1;
int fast_translate, sb;
re_match_context_t mctx;
char *fastmap = ((preg->fastmap != NULL && preg->fastmap_accurate
&& range && !preg->can_be_null) ? preg->fastmap : NULL);
/* Check if the DFA haven't been compiled. */
if (BE (preg->used == 0 || dfa->init_state == NULL
|| dfa->init_state_word == NULL || dfa->init_state_nl == NULL
|| dfa->init_state_begbuf == NULL, 0))
return REG_NOMATCH;
re_node_set_init_empty (&empty_set);
memset (&mctx, '\0', sizeof (re_match_context_t));
/* We must check the longest matching, if nmatch > 0. */
fl_longest_match = (nmatch != 0 || dfa->nbackref);
err = re_string_allocate (&input, string, length, dfa->nodes_len + 1,
preg->translate, preg->syntax & RE_ICASE);
if (BE (err != REG_NOERROR, 0))
goto free_return;
input.stop = stop;
err = match_ctx_init (&mctx, eflags, &input, dfa->nbackref * 2);
if (BE (err != REG_NOERROR, 0))
goto free_return;
/* We will log all the DFA states through which the dfa pass,
if nmatch > 1, or this dfa has "multibyte node", which is a
back-reference or a node which can accept multibyte character or
multi character collating element. */
if (nmatch > 1 || dfa->has_mb_node)
{
mctx.state_log = re_malloc (re_dfastate_t *, dfa->nodes_len + 1);
if (BE (mctx.state_log == NULL, 0))
{
err = REG_ESPACE;
goto free_return;
}
}
else
mctx.state_log = NULL;
#ifdef DEBUG
/* We assume front-end functions already check them. */
assert (start + range >= 0 && start + range <= length);
#endif
match_first = start;
input.tip_context = ((eflags & REG_NOTBOL) ? CONTEXT_BEGBUF
: CONTEXT_NEWLINE | CONTEXT_BEGBUF);
/* Check incrementally whether of not the input string match. */
incr = (range < 0) ? -1 : 1;
left_lim = (range < 0) ? start + range : start;
right_lim = (range < 0) ? start : start + range;
#ifdef RE_ENABLE_I18N
sb = re_mb_cur_max == 1;
#else
sb = 1;
#endif
fast_translate = sb || !(preg->syntax & RE_ICASE || preg->translate);
for (;;)
{
/* At first get the current byte from input string. */
if (fastmap)
{
if (BE (fast_translate, 1))
{
unsigned RE_TRANSLATE_TYPE t
= (unsigned RE_TRANSLATE_TYPE) preg->translate;
if (BE (range >= 0, 1))
{
if (BE (t != NULL, 0))
{
while (BE (match_first < right_lim, 1)
&& !fastmap[t[(unsigned char) string[match_first]]])
++match_first;
}
else
{
while (BE (match_first < right_lim, 1)
&& !fastmap[(unsigned char) string[match_first]])
++match_first;
}
if (BE (match_first == right_lim, 0))
{
int ch = match_first >= length
? 0 : (unsigned char) string[match_first];
if (!fastmap[t ? t[ch] : ch])
break;
}
}
else
{
while (match_first >= left_lim)
{
int ch = match_first >= length
? 0 : (unsigned char) string[match_first];
if (fastmap[t ? t[ch] : ch])
break;
--match_first;
}
if (match_first < left_lim)
break;
}
}
else
{
int ch;
do
{
/* In this case, we can't determine easily the current byte,
since it might be a component byte of a multibyte
character. Then we use the constructed buffer
instead. */
/* If MATCH_FIRST is out of the valid range, reconstruct the
buffers. */
if (input.raw_mbs_idx + input.valid_len <= match_first
|| match_first < input.raw_mbs_idx)
{
err = re_string_reconstruct (&input, match_first, eflags,
preg->newline_anchor);
if (BE (err != REG_NOERROR, 0))
goto free_return;
}
/* If MATCH_FIRST is out of the buffer, leave it as '\0'.
Note that MATCH_FIRST must not be smaller than 0. */
ch = ((match_first >= length) ? 0
: re_string_byte_at (&input,
match_first - input.raw_mbs_idx));
if (fastmap[ch])
break;
match_first += incr;
}
while (match_first >= left_lim && match_first <= right_lim);
if (! fastmap[ch])
break;
}
}
/* Reconstruct the buffers so that the matcher can assume that
the matching starts from the begining of the buffer. */
err = re_string_reconstruct (&input, match_first, eflags,
preg->newline_anchor);
if (BE (err != REG_NOERROR, 0))
goto free_return;
#ifdef RE_ENABLE_I18N
/* Eliminate it when it is a component of a multibyte character
and isn't the head of a multibyte character. */
if (sb || re_string_first_byte (&input, 0))
#endif
{
/* It seems to be appropriate one, then use the matcher. */
/* We assume that the matching starts from 0. */
mctx.state_log_top = mctx.nbkref_ents = mctx.max_mb_elem_len = 0;
match_last = check_matching (preg, &mctx, 0, fl_longest_match);
if (match_last != -1)
{
if (BE (match_last == -2, 0))
{
err = REG_ESPACE;
goto free_return;
}
else
{
mctx.match_last = match_last;
if ((!preg->no_sub && nmatch > 1) || dfa->nbackref)
{
re_dfastate_t *pstate = mctx.state_log[match_last];
mctx.last_node = check_halt_state_context (preg, pstate,
&mctx, match_last);
}
if ((!preg->no_sub && nmatch > 1 && dfa->has_plural_match)
|| dfa->nbackref)
{
err = prune_impossible_nodes (preg, &mctx);
if (err == REG_NOERROR)
break;
if (BE (err != REG_NOMATCH, 0))
goto free_return;
}
else
break; /* We found a matching. */
}
}
match_ctx_clean (&mctx);
}
/* Update counter. */
match_first += incr;
if (match_first < left_lim || right_lim < match_first)
break;
}
/* Set pmatch[] if we need. */
if (match_last != -1 && nmatch > 0)
{
int reg_idx;
/* Initialize registers. */
for (reg_idx = 0; reg_idx < nmatch; ++reg_idx)
pmatch[reg_idx].rm_so = pmatch[reg_idx].rm_eo = -1;
/* Set the points where matching start/end. */
pmatch[0].rm_so = 0;
pmatch[0].rm_eo = mctx.match_last;
if (!preg->no_sub && nmatch > 1)
{
err = set_regs (preg, &mctx, nmatch, pmatch,
dfa->has_plural_match && dfa->nbackref > 0);
if (BE (err != REG_NOERROR, 0))
goto free_return;
}
/* At last, add the offset to the each registers, since we slided
the buffers so that We can assume that the matching starts from 0. */
for (reg_idx = 0; reg_idx < nmatch; ++reg_idx)
if (pmatch[reg_idx].rm_so != -1)
{
pmatch[reg_idx].rm_so += match_first;
pmatch[reg_idx].rm_eo += match_first;
}
}
err = (match_last == -1) ? REG_NOMATCH : REG_NOERROR;
free_return:
re_free (mctx.state_log);
if (dfa->nbackref)
match_ctx_free (&mctx);
re_string_destruct (&input);
return err;
}
static reg_errcode_t
prune_impossible_nodes (preg, mctx)
const regex_t *preg;
re_match_context_t *mctx;
{
int halt_node, match_last;
reg_errcode_t ret;
re_dfa_t *dfa = (re_dfa_t *)preg->buffer;
re_dfastate_t **sifted_states;
re_dfastate_t **lim_states = NULL;
re_sift_context_t sctx;
#ifdef DEBUG
assert (mctx->state_log != NULL);
#endif
match_last = mctx->match_last;
halt_node = mctx->last_node;
sifted_states = re_malloc (re_dfastate_t *, match_last + 1);
if (BE (sifted_states == NULL, 0))
{
ret = REG_ESPACE;
goto free_return;
}
if (dfa->nbackref)
{
lim_states = re_malloc (re_dfastate_t *, match_last + 1);
if (BE (lim_states == NULL, 0))
{
ret = REG_ESPACE;
goto free_return;
}
while (1)
{
memset (lim_states, '\0',
sizeof (re_dfastate_t *) * (match_last + 1));
match_ctx_clear_flag (mctx);
sift_ctx_init (&sctx, sifted_states, lim_states, halt_node,
match_last, 0);
ret = sift_states_backward (preg, mctx, &sctx);
re_node_set_free (&sctx.limits);
if (BE (ret != REG_NOERROR, 0))
goto free_return;
if (sifted_states[0] != NULL || lim_states[0] != NULL)
break;
do
{
--match_last;
if (match_last < 0)
{
ret = REG_NOMATCH;
goto free_return;
}
} while (!mctx->state_log[match_last]->halt);
halt_node = check_halt_state_context (preg,
mctx->state_log[match_last],
mctx, match_last);
}
ret = merge_state_array (dfa, sifted_states, lim_states,
match_last + 1);
re_free (lim_states);
lim_states = NULL;
if (BE (ret != REG_NOERROR, 0))
goto free_return;
}
else
{
sift_ctx_init (&sctx, sifted_states, lim_states, halt_node,
match_last, 0);
ret = sift_states_backward (preg, mctx, &sctx);
re_node_set_free (&sctx.limits);
if (BE (ret != REG_NOERROR, 0))
goto free_return;
}
re_free (mctx->state_log);
mctx->state_log = sifted_states;
sifted_states = NULL;
mctx->last_node = halt_node;
mctx->match_last = match_last;
ret = REG_NOERROR;
free_return:
re_free (sifted_states);
re_free (lim_states);
return ret;
}
/* Acquire an initial state and return it.
We must select appropriate initial state depending on the context,
since initial states may have constraints like "\<", "^", etc.. */
static inline re_dfastate_t *
acquire_init_state_context (err, preg, mctx, idx)
reg_errcode_t *err;
const regex_t *preg;
const re_match_context_t *mctx;
int idx;
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
*err = REG_NOERROR;
if (dfa->init_state->has_constraint)
{
unsigned int context;
context = re_string_context_at (mctx->input, idx - 1, mctx->eflags,
preg->newline_anchor);
if (IS_WORD_CONTEXT (context))
return dfa->init_state_word;
else if (IS_ORDINARY_CONTEXT (context))
return dfa->init_state;
else if (IS_BEGBUF_CONTEXT (context) && IS_NEWLINE_CONTEXT (context))
return dfa->init_state_begbuf;
else if (IS_NEWLINE_CONTEXT (context))
return dfa->init_state_nl;
else if (IS_BEGBUF_CONTEXT (context))
{
/* It is relatively rare case, then calculate on demand. */
return re_acquire_state_context (err, dfa,
dfa->init_state->entrance_nodes,
context);
}
else
/* Must not happen? */
return dfa->init_state;
}
else
return dfa->init_state;
}
/* Check whether the regular expression match input string INPUT or not,
and return the index where the matching end, return -1 if not match,
or return -2 in case of an error.
FL_SEARCH means we must search where the matching starts,
FL_LONGEST_MATCH means we want the POSIX longest matching.
Note that the matcher assume that the maching starts from the current
index of the buffer. */
static int
check_matching (preg, mctx, fl_search, fl_longest_match)
const regex_t *preg;
re_match_context_t *mctx;
int fl_search, fl_longest_match;
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
reg_errcode_t err;
int match = 0;
int match_last = -1;
int cur_str_idx = re_string_cur_idx (mctx->input);
re_dfastate_t *cur_state;
cur_state = acquire_init_state_context (&err, preg, mctx, cur_str_idx);
/* An initial state must not be NULL(invalid state). */
if (BE (cur_state == NULL, 0))
return -2;
if (mctx->state_log != NULL)
mctx->state_log[cur_str_idx] = cur_state;
/* Check OP_OPEN_SUBEXP in the initial state in case that we use them
later. E.g. Processing back references. */
if (dfa->nbackref)
{
err = check_subexp_matching_top (dfa, mctx, &cur_state->nodes, 0);
if (BE (err != REG_NOERROR, 0))
return err;
}
if (cur_state->has_backref)
{
err = transit_state_bkref (preg, &cur_state->nodes, mctx);
if (BE (err != REG_NOERROR, 0))
return err;
}
/* If the RE accepts NULL string. */
if (cur_state->halt)
{
if (!cur_state->has_constraint
|| check_halt_state_context (preg, cur_state, mctx, cur_str_idx))
{