2
* re_*exec and friends - match REs
4
* Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
6
* Development of this software was funded, in part, by Cray Research Inc.,
7
* UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
8
* Corporation, none of whom are responsible for the results. The author
11
* Redistribution and use in source and binary forms -- with or without
12
* modification -- are permitted for any purpose, provided that
13
* redistributions in source form retain this entire copyright notice and
14
* indicate the origin and nature of any modifications.
16
* I'd appreciate being given credit for this package in the documentation
17
* of software which uses it, but that is not a requirement.
19
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
20
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
21
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
22
* HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
23
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
24
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
25
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
26
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
27
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
28
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30
* $PostgreSQL: pgsql/src/backend/regex/regexec.c,v 1.24 2003-11-29 19:51:55 pgsql Exp $
34
#include "regex/regguts.h"
38
/* lazy-DFA representation */
40
{ /* "pointer" to an outarc */
47
unsigned *states; /* pointer to bitvector */
48
unsigned hash; /* hash of bitvector */
49
#define HASH(bv, nw) (((nw) == 1) ? *(bv) : hash(bv, nw))
50
#define HIT(h,bv,ss,nw) ((ss)->hash == (h) && ((nw) == 1 || \
51
memcmp(VS(bv), VS((ss)->states), (nw)*sizeof(unsigned)) == 0))
53
#define STARTER 01 /* the initial state set */
54
#define POSTSTATE 02 /* includes the goal state */
55
#define LOCKED 04 /* locked in cache */
56
#define NOPROGRESS 010 /* zero-progress state set */
57
struct arcp ins; /* chain of inarcs pointing here */
58
chr *lastseen; /* last entered on arrival here */
59
struct sset **outs; /* outarc vector indexed by color */
60
struct arcp *inchain; /* chain-pointer vector for outarcs */
65
int nssets; /* size of cache */
66
int nssused; /* how many entries occupied yet */
67
int nstates; /* number of states */
68
int ncolors; /* length of outarc and inchain vectors */
69
int wordsper; /* length of state-set bitvectors */
70
struct sset *ssets; /* state-set cache */
71
unsigned *statesarea; /* bitvector storage */
72
unsigned *work; /* pointer to work area within statesarea */
73
struct sset **outsarea; /* outarc-vector storage */
74
struct arcp *incarea; /* inchain storage */
77
chr *lastpost; /* location of last cache-flushed success */
78
chr *lastnopr; /* location of last cache-flushed
80
struct sset *search; /* replacement-search-pointer memory */
81
int cptsmalloced; /* were the areas individually malloced? */
82
char *mallocarea; /* self, or master malloced area, or NULL */
85
#define WORK 1 /* number of work bitvectors needed */
87
/* setup for non-malloc allocation for small cases */
88
#define FEWSTATES 20 /* must be less than UBITS */
93
struct sset ssets[FEWSTATES * 2];
94
unsigned statesarea[FEWSTATES * 2 + WORK];
95
struct sset *outsarea[FEWSTATES * 2 * FEWCOLORS];
96
struct arcp incarea[FEWSTATES * 2 * FEWCOLORS];
99
#define DOMALLOC ((struct smalldfa *)NULL) /* force malloc */
103
/* internal variables, bundled for easy passing around */
108
int eflags; /* copies of arguments */
111
rm_detail_t *details;
112
chr *start; /* start of string */
113
chr *stop; /* just past end of string */
114
int err; /* error code if any (0 none) */
115
regoff_t *mem; /* memory vector for backtracking */
116
struct smalldfa dfa1;
117
struct smalldfa dfa2;
120
#define VISERR(vv) ((vv)->err != 0) /* have we seen an error yet? */
121
#define ISERR() VISERR(v)
122
#define VERR(vv,e) (((vv)->err) ? (vv)->err : ((vv)->err = (e)))
123
#define ERR(e) VERR(v, e) /* record an error */
124
#define NOERR() {if (ISERR()) return v->err;} /* if error seen, return
126
#define OFF(p) ((p) - v->start)
127
#define LOFF(p) ((long)OFF(p))
132
* forward declarations
134
/* === regexec.c === */
135
static int find(struct vars *, struct cnfa *, struct colormap *);
136
static int cfind(struct vars *, struct cnfa *, struct colormap *);
137
static int cfindloop(struct vars *, struct cnfa *, struct colormap *, struct dfa *, struct dfa *, chr **);
138
static void zapsubs(regmatch_t *, size_t);
139
static void zapmem(struct vars *, struct subre *);
140
static void subset(struct vars *, struct subre *, chr *, chr *);
141
static int dissect(struct vars *, struct subre *, chr *, chr *);
142
static int condissect(struct vars *, struct subre *, chr *, chr *);
143
static int altdissect(struct vars *, struct subre *, chr *, chr *);
144
static int cdissect(struct vars *, struct subre *, chr *, chr *);
145
static int ccondissect(struct vars *, struct subre *, chr *, chr *);
146
static int crevdissect(struct vars *, struct subre *, chr *, chr *);
147
static int cbrdissect(struct vars *, struct subre *, chr *, chr *);
148
static int caltdissect(struct vars *, struct subre *, chr *, chr *);
150
/* === rege_dfa.c === */
151
static chr *longest(struct vars *, struct dfa *, chr *, chr *, int *);
152
static chr *shortest(struct vars *, struct dfa *, chr *, chr *, chr *, chr **, int *);
153
static chr *lastcold(struct vars *, struct dfa *);
154
static struct dfa *newdfa(struct vars *, struct cnfa *, struct colormap *, struct smalldfa *);
155
static void freedfa(struct dfa *);
156
static unsigned hash(unsigned *, int);
157
static struct sset *initialize(struct vars *, struct dfa *, chr *);
158
static struct sset *miss(struct vars *, struct dfa *, struct sset *, pcolor, chr *, chr *);
159
static int lacon(struct vars *, struct cnfa *, chr *, pcolor);
160
static struct sset *getvacant(struct vars *, struct dfa *, chr *, chr *);
161
static struct sset *pickss(struct vars *, struct dfa *, chr *, chr *);
165
* pg_regexec - match regular expression
168
pg_regexec(regex_t *re,
171
rm_detail_t *details,
177
register struct vars *v = &var;
183
regmatch_t mat[LOCALMAT];
186
regoff_t mem[LOCALMEM];
189
if (re == NULL || string == NULL || re->re_magic != REMAGIC)
191
if (re->re_csize != sizeof(chr))
196
v->g = (struct guts *) re->re_guts;
197
if ((v->g->cflags & REG_EXPECT) && details == NULL)
199
if (v->g->info & REG_UIMPOSSIBLE)
201
backref = (v->g->info & REG_UBACKREF) ? 1 : 0;
203
if (v->g->cflags & REG_NOSUB)
204
nmatch = 0; /* override client */
209
if (v->g->nsub + 1 <= LOCALMAT)
212
v->pmatch = (regmatch_t *) MALLOC((v->g->nsub + 1) *
214
if (v->pmatch == NULL)
216
v->nmatch = v->g->nsub + 1;
220
v->details = details;
221
v->start = (chr *) string;
222
v->stop = (chr *) string + len;
226
/* need retry memory */
227
assert(v->g->ntree >= 0);
228
n = (size_t) v->g->ntree;
232
v->mem = (regoff_t *) MALLOC(n * sizeof(regoff_t));
235
if (v->pmatch != pmatch && v->pmatch != mat)
244
assert(v->g->tree != NULL);
246
st = cfind(v, &v->g->tree->cnfa, &v->g->cmap);
248
st = find(v, &v->g->tree->cnfa, &v->g->cmap);
250
/* copy (portion of) match vector over if necessary */
251
if (st == REG_OKAY && v->pmatch != pmatch && nmatch > 0)
253
zapsubs(pmatch, nmatch);
254
n = (nmatch < v->nmatch) ? nmatch : v->nmatch;
255
memcpy(VS(pmatch), VS(v->pmatch), n * sizeof(regmatch_t));
259
if (v->pmatch != pmatch && v->pmatch != mat)
261
if (v->mem != NULL && v->mem != mem)
267
* find - find a match for the main NFA (no-complications case)
270
find(struct vars * v,
272
struct colormap * cm)
279
chr *open; /* open and close of range of possible
283
int shorter = (v->g->tree->flags & SHORTER) ? 1 : 0;
285
/* first, a shot with the search RE */
286
s = newdfa(v, &v->g->search, cm, &v->dfa1);
287
assert(!(ISERR() && s != NULL));
289
MDEBUG(("\nsearch at %ld\n", LOFF(v->start)));
291
close = shortest(v, s, v->start, v->start, v->stop, &cold, (int *) NULL);
294
if (v->g->cflags & REG_EXPECT)
296
assert(v->details != NULL);
298
v->details->rm_extend.rm_so = OFF(cold);
300
v->details->rm_extend.rm_so = OFF(v->stop);
301
v->details->rm_extend.rm_eo = OFF(v->stop); /* unknown */
303
if (close == NULL) /* not found */
305
if (v->nmatch == 0) /* found, don't need exact location */
308
/* find starting point and match */
309
assert(cold != NULL);
312
MDEBUG(("between %ld and %ld\n", LOFF(open), LOFF(close)));
313
d = newdfa(v, cnfa, cm, &v->dfa1);
314
assert(!(ISERR() && d != NULL));
316
for (begin = open; begin <= close; begin++)
318
MDEBUG(("\nfind trying at %ld\n", LOFF(begin)));
320
end = shortest(v, d, begin, begin, v->stop,
321
(chr **) NULL, &hitend);
323
end = longest(v, d, begin, v->stop, &hitend);
325
if (hitend && cold == NULL)
328
break; /* NOTE BREAK OUT */
330
assert(end != NULL); /* search RE succeeded so loop should */
333
/* and pin down details */
334
assert(v->nmatch > 0);
335
v->pmatch[0].rm_so = OFF(begin);
336
v->pmatch[0].rm_eo = OFF(end);
337
if (v->g->cflags & REG_EXPECT)
340
v->details->rm_extend.rm_so = OFF(cold);
342
v->details->rm_extend.rm_so = OFF(v->stop);
343
v->details->rm_extend.rm_eo = OFF(v->stop); /* unknown */
345
if (v->nmatch == 1) /* no need for submatches */
349
zapsubs(v->pmatch, v->nmatch);
350
return dissect(v, v->g->tree, begin, end);
354
* cfind - find a match for the main NFA (with complications)
357
cfind(struct vars * v,
359
struct colormap * cm)
366
s = newdfa(v, &v->g->search, cm, &v->dfa1);
368
d = newdfa(v, cnfa, cm, &v->dfa2);
376
ret = cfindloop(v, cnfa, cm, d, s, &cold);
381
if (v->g->cflags & REG_EXPECT)
383
assert(v->details != NULL);
385
v->details->rm_extend.rm_so = OFF(cold);
387
v->details->rm_extend.rm_so = OFF(v->stop);
388
v->details->rm_extend.rm_eo = OFF(v->stop); /* unknown */
394
* cfindloop - the heart of cfind
397
cfindloop(struct vars * v,
399
struct colormap * cm,
402
chr **coldp) /* where to put coldstart pointer */
407
chr *open; /* open and close of range of possible
413
int shorter = v->g->tree->flags & SHORTER;
416
assert(d != NULL && s != NULL);
421
MDEBUG(("\ncsearch at %ld\n", LOFF(close)));
422
close = shortest(v, s, close, close, v->stop, &cold, (int *) NULL);
424
break; /* NOTE BREAK */
425
assert(cold != NULL);
428
MDEBUG(("cbetween %ld and %ld\n", LOFF(open), LOFF(close)));
429
for (begin = open; begin <= close; begin++)
431
MDEBUG(("\ncfind trying at %ld\n", LOFF(begin)));
437
end = shortest(v, d, begin, estart,
438
estop, (chr **) NULL, &hitend);
440
end = longest(v, d, begin, estop,
442
if (hitend && cold == NULL)
445
break; /* NOTE BREAK OUT */
446
MDEBUG(("tentative end %ld\n", LOFF(end)));
447
zapsubs(v->pmatch, v->nmatch);
448
zapmem(v, v->g->tree);
449
er = cdissect(v, v->g->tree, begin, end);
454
v->pmatch[0].rm_so = OFF(begin);
455
v->pmatch[0].rm_eo = OFF(end);
460
if (er != REG_NOMATCH)
465
if ((shorter) ? end == estop : end == begin)
467
/* no point in trying again */
471
/* go around and try again */
478
} while (close < v->stop);
485
* zapsubs - initialize the subexpression matches to "no match"
488
zapsubs(regmatch_t *p,
493
for (i = n - 1; i > 0; i--)
501
* zapmem - initialize the retry memory of a subtree to zeros
504
zapmem(struct vars * v,
510
assert(v->mem != NULL);
511
v->mem[t->retry] = 0;
514
assert(t->subno > 0);
515
v->pmatch[t->subno].rm_so = -1;
516
v->pmatch[t->subno].rm_eo = -1;
521
if (t->right != NULL)
526
* subset - set any subexpression relevant to a successful subre
529
subset(struct vars * v,
537
if ((size_t) n >= v->nmatch)
540
MDEBUG(("setting %d\n", n));
541
v->pmatch[n].rm_so = OFF(begin);
542
v->pmatch[n].rm_eo = OFF(end);
546
* dissect - determine subexpression matches (uncomplicated case)
548
static int /* regexec return code */
549
dissect(struct vars * v,
551
chr *begin, /* beginning of relevant substring */
552
chr *end) /* end of same */
555
MDEBUG(("dissect %ld-%ld\n", LOFF(begin), LOFF(end)));
559
case '=': /* terminal node */
560
assert(t->left == NULL && t->right == NULL);
561
return REG_OKAY; /* no action, parent did the work */
563
case '|': /* alternation */
564
assert(t->left != NULL);
565
return altdissect(v, t, begin, end);
567
case 'b': /* back ref -- shouldn't be calling us! */
570
case '.': /* concatenation */
571
assert(t->left != NULL && t->right != NULL);
572
return condissect(v, t, begin, end);
574
case '(': /* capturing */
575
assert(t->left != NULL && t->right == NULL);
576
assert(t->subno > 0);
577
subset(v, t, begin, end);
578
return dissect(v, t->left, begin, end);
587
* condissect - determine concatenation subexpression matches (uncomplicated)
589
static int /* regexec return code */
590
condissect(struct vars * v,
592
chr *begin, /* beginning of relevant substring */
593
chr *end) /* end of same */
599
int shorter = (t->left->flags & SHORTER) ? 1 : 0;
600
chr *stop = (shorter) ? end : begin;
602
assert(t->op == '.');
603
assert(t->left != NULL && t->left->cnfa.nstates > 0);
604
assert(t->right != NULL && t->right->cnfa.nstates > 0);
606
d = newdfa(v, &t->left->cnfa, &v->g->cmap, &v->dfa1);
608
d2 = newdfa(v, &t->right->cnfa, &v->g->cmap, &v->dfa2);
616
/* pick a tentative midpoint */
618
mid = shortest(v, d, begin, begin, end, (chr **) NULL,
621
mid = longest(v, d, begin, end, (int *) NULL);
628
MDEBUG(("tentative midpoint %ld\n", LOFF(mid)));
630
/* iterate until satisfaction or failure */
631
while (longest(v, d2, mid, end, (int *) NULL) != end)
633
/* that midpoint didn't work, find a new one */
636
/* all possibilities exhausted! */
637
MDEBUG(("no midpoint!\n"));
643
mid = shortest(v, d, begin, mid + 1, end, (chr **) NULL,
646
mid = longest(v, d, begin, mid - 1, (int *) NULL);
649
/* failed to find a new one! */
650
MDEBUG(("failed midpoint!\n"));
655
MDEBUG(("new midpoint %ld\n", LOFF(mid)));
659
MDEBUG(("successful\n"));
662
i = dissect(v, t->left, begin, mid);
665
return dissect(v, t->right, mid, end);
669
* altdissect - determine alternative subexpression matches (uncomplicated)
671
static int /* regexec return code */
672
altdissect(struct vars * v,
674
chr *begin, /* beginning of relevant substring */
675
chr *end) /* end of same */
681
assert(t->op == '|');
683
for (i = 0; t != NULL; t = t->right, i++)
685
MDEBUG(("trying %dth\n", i));
686
assert(t->left != NULL && t->left->cnfa.nstates > 0);
687
d = newdfa(v, &t->left->cnfa, &v->g->cmap, &v->dfa1);
690
if (longest(v, d, begin, end, (int *) NULL) == end)
692
MDEBUG(("success\n"));
694
return dissect(v, t->left, begin, end);
698
return REG_ASSERT; /* none of them matched?!? */
702
* cdissect - determine subexpression matches (with complications)
703
* The retry memory stores the offset of the trial midpoint from begin,
704
* plus 1 so that 0 uniquely means "clean slate".
706
static int /* regexec return code */
707
cdissect(struct vars * v,
709
chr *begin, /* beginning of relevant substring */
710
chr *end) /* end of same */
715
MDEBUG(("cdissect %ld-%ld %c\n", LOFF(begin), LOFF(end), t->op));
719
case '=': /* terminal node */
720
assert(t->left == NULL && t->right == NULL);
721
return REG_OKAY; /* no action, parent did the work */
723
case '|': /* alternation */
724
assert(t->left != NULL);
725
return caltdissect(v, t, begin, end);
727
case 'b': /* back ref -- shouldn't be calling us! */
728
assert(t->left == NULL && t->right == NULL);
729
return cbrdissect(v, t, begin, end);
731
case '.': /* concatenation */
732
assert(t->left != NULL && t->right != NULL);
733
return ccondissect(v, t, begin, end);
735
case '(': /* capturing */
736
assert(t->left != NULL && t->right == NULL);
737
assert(t->subno > 0);
738
er = cdissect(v, t->left, begin, end);
740
subset(v, t, begin, end);
750
* ccondissect - concatenation subexpression matches (with complications)
751
* The retry memory stores the offset of the trial midpoint from begin,
752
* plus 1 so that 0 uniquely means "clean slate".
754
static int /* regexec return code */
755
ccondissect(struct vars * v,
757
chr *begin, /* beginning of relevant substring */
758
chr *end) /* end of same */
765
assert(t->op == '.');
766
assert(t->left != NULL && t->left->cnfa.nstates > 0);
767
assert(t->right != NULL && t->right->cnfa.nstates > 0);
769
if (t->left->flags & SHORTER) /* reverse scan */
770
return crevdissect(v, t, begin, end);
772
d = newdfa(v, &t->left->cnfa, &v->g->cmap, DOMALLOC);
775
d2 = newdfa(v, &t->right->cnfa, &v->g->cmap, DOMALLOC);
781
MDEBUG(("cconcat %d\n", t->retry));
783
/* pick a tentative midpoint */
784
if (v->mem[t->retry] == 0)
786
mid = longest(v, d, begin, end, (int *) NULL);
793
MDEBUG(("tentative midpoint %ld\n", LOFF(mid)));
794
v->mem[t->retry] = (mid - begin) + 1;
798
mid = begin + (v->mem[t->retry] - 1);
799
MDEBUG(("working midpoint %ld\n", LOFF(mid)));
802
/* iterate until satisfaction or failure */
805
/* try this midpoint on for size */
806
er = cdissect(v, t->left, begin, mid);
807
if (er == REG_OKAY &&
808
longest(v, d2, mid, end, (int *) NULL) == end &&
809
(er = cdissect(v, t->right, mid, end)) ==
811
break; /* NOTE BREAK OUT */
812
if (er != REG_OKAY && er != REG_NOMATCH)
819
/* that midpoint didn't work, find a new one */
822
/* all possibilities exhausted */
823
MDEBUG(("%d no midpoint\n", t->retry));
828
mid = longest(v, d, begin, mid - 1, (int *) NULL);
831
/* failed to find a new one */
832
MDEBUG(("%d failed midpoint\n", t->retry));
837
MDEBUG(("%d: new midpoint %ld\n", t->retry, LOFF(mid)));
838
v->mem[t->retry] = (mid - begin) + 1;
844
MDEBUG(("successful\n"));
851
* crevdissect - determine backref shortest-first subexpression matches
852
* The retry memory stores the offset of the trial midpoint from begin,
853
* plus 1 so that 0 uniquely means "clean slate".
855
static int /* regexec return code */
856
crevdissect(struct vars * v,
858
chr *begin, /* beginning of relevant substring */
859
chr *end) /* end of same */
866
assert(t->op == '.');
867
assert(t->left != NULL && t->left->cnfa.nstates > 0);
868
assert(t->right != NULL && t->right->cnfa.nstates > 0);
869
assert(t->left->flags & SHORTER);
871
/* concatenation -- need to split the substring between parts */
872
d = newdfa(v, &t->left->cnfa, &v->g->cmap, DOMALLOC);
875
d2 = newdfa(v, &t->right->cnfa, &v->g->cmap, DOMALLOC);
881
MDEBUG(("crev %d\n", t->retry));
883
/* pick a tentative midpoint */
884
if (v->mem[t->retry] == 0)
886
mid = shortest(v, d, begin, begin, end, (chr **) NULL, (int *) NULL);
893
MDEBUG(("tentative midpoint %ld\n", LOFF(mid)));
894
v->mem[t->retry] = (mid - begin) + 1;
898
mid = begin + (v->mem[t->retry] - 1);
899
MDEBUG(("working midpoint %ld\n", LOFF(mid)));
902
/* iterate until satisfaction or failure */
905
/* try this midpoint on for size */
906
er = cdissect(v, t->left, begin, mid);
907
if (er == REG_OKAY &&
908
longest(v, d2, mid, end, (int *) NULL) == end &&
909
(er = cdissect(v, t->right, mid, end)) ==
911
break; /* NOTE BREAK OUT */
912
if (er != REG_OKAY && er != REG_NOMATCH)
919
/* that midpoint didn't work, find a new one */
922
/* all possibilities exhausted */
923
MDEBUG(("%d no midpoint\n", t->retry));
928
mid = shortest(v, d, begin, mid + 1, end, (chr **) NULL, (int *) NULL);
931
/* failed to find a new one */
932
MDEBUG(("%d failed midpoint\n", t->retry));
937
MDEBUG(("%d: new midpoint %ld\n", t->retry, LOFF(mid)));
938
v->mem[t->retry] = (mid - begin) + 1;
944
MDEBUG(("successful\n"));
951
* cbrdissect - determine backref subexpression matches
953
static int /* regexec return code */
954
cbrdissect(struct vars * v,
956
chr *begin, /* beginning of relevant substring */
957
chr *end) /* end of same */
969
assert(t->op == 'b');
971
assert((size_t) n < v->nmatch);
973
MDEBUG(("cbackref n%d %d{%d-%d}\n", t->retry, n, min, max));
975
if (v->pmatch[n].rm_so == -1)
977
paren = v->start + v->pmatch[n].rm_so;
978
len = v->pmatch[n].rm_eo - v->pmatch[n].rm_so;
980
/* no room to maneuver -- retries are pointless */
981
if (v->mem[t->retry])
983
v->mem[t->retry] = 1;
985
/* special-case zero-length string */
993
/* and too-short string */
994
assert(end >= begin);
995
if ((size_t) (end - begin) < len)
999
/* count occurrences */
1001
for (p = begin; p <= stop && (i < max || max == INFINITY); p += len)
1003
if ((*v->g->compare) (paren, p, len) != 0)
1007
MDEBUG(("cbackref found %d\n", i));
1009
/* and sort it out */
1010
if (p != end) /* didn't consume all of it */
1012
if (min <= i && (i <= max || max == INFINITY))
1014
return REG_NOMATCH; /* out of range */
1018
* caltdissect - determine alternative subexpression matches (w. complications)
1020
static int /* regexec return code */
1021
caltdissect(struct vars * v,
1023
chr *begin, /* beginning of relevant substring */
1024
chr *end) /* end of same */
1029
#define UNTRIED 0 /* not yet tried at all */
1030
#define TRYING 1 /* top matched, trying submatches */
1031
#define TRIED 2 /* top didn't match or submatches
1036
assert(t->op == '|');
1037
if (v->mem[t->retry] == TRIED)
1038
return caltdissect(v, t->right, begin, end);
1040
MDEBUG(("calt n%d\n", t->retry));
1041
assert(t->left != NULL);
1043
if (v->mem[t->retry] == UNTRIED)
1045
d = newdfa(v, &t->left->cnfa, &v->g->cmap, DOMALLOC);
1048
if (longest(v, d, begin, end, (int *) NULL) != end)
1051
v->mem[t->retry] = TRIED;
1052
return caltdissect(v, t->right, begin, end);
1055
MDEBUG(("calt matched\n"));
1056
v->mem[t->retry] = TRYING;
1059
er = cdissect(v, t->left, begin, end);
1060
if (er != REG_NOMATCH)
1063
v->mem[t->retry] = TRIED;
1064
return caltdissect(v, t->right, begin, end);
1069
#include "rege_dfa.c"