2 * Copyright (c) 1992, 1993, 1994 Henry Spencer.
3 * Copyright (c) 1992, 1993, 1994
4 * The Regents of the University of California. All rights reserved.
6 * This code is derived from software contributed to Berkeley by
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 * must display the following acknowledgement:
19 * This product includes software developed by the University of
20 * California, Berkeley and its contributors.
21 * 4. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * @(#)engine.c 8.5 (Berkeley) 3/20/94
39 * $FreeBSD: src/lib/libc/regex/engine.c,v 1.5.8.1 2000/07/31 06:30:37 dcs Exp $
40 * $DragonFly: src/lib/libc/regex/engine.c,v 1.7 2005/11/20 09:18:37 swildner Exp $
44 * The matching engine and friends. This file is #included by regexec.c
45 * after suitable #defines of a variety of macros used herein, so that
46 * different state representations can be used without duplicating masses
51 #define matcher smatcher
54 #define dissect sdissect
55 #define backref sbackref
62 #define matcher lmatcher
65 #define dissect ldissect
66 #define backref lbackref
73 /* another structure passed up and down to avoid zillions of parameters */
77 regmatch_t *pmatch; /* [nsub+1] (0 element unused) */
78 char *offp; /* offsets work from here */
79 char *beginp; /* start of string -- virtual NUL precedes */
80 char *endp; /* end of string -- virtual NUL here */
81 char *coldp; /* can be no match starting before here */
82 char **lastpos; /* [nplus+1] */
84 states st; /* current states */
85 states fresh; /* states for a fresh start */
86 states tmp; /* temporary */
87 states empty; /* empty set of states */
90 /* ========= begin header generated by ./mkh ========= */
95 /* === engine.c === */
96 static int matcher(struct re_guts *g, char *string, size_t nmatch, regmatch_t pmatch[], int eflags);
97 static char *dissect(struct match *m, char *start, char *stop, sopno startst, sopno stopst);
98 static char *backref(struct match *m, char *start, char *stop, sopno startst, sopno stopst, sopno lev);
99 static char *fast(struct match *m, char *start, char *stop, sopno startst, sopno stopst);
100 static char *slow(struct match *m, char *start, char *stop, sopno startst, sopno stopst);
101 static states step(struct re_guts *g, sopno start, sopno stop, states bef, int ch, states aft);
104 #define BOLEOL (BOL+2)
105 #define NOTHING (BOL+3)
108 #define CODEMAX (BOL+5) /* highest code used */
109 #define NONCHAR(c) ((c) > CHAR_MAX)
110 #define NNONCHAR (CODEMAX-CHAR_MAX)
112 static void print(struct match *m, char *caption, states st, int ch, FILE *d);
115 static void at(struct match *m, char *title, char *start, char *stop, sopno startst, sopno stopst);
118 static char *pchar(int ch);
124 /* ========= end header generated by ./mkh ========= */
127 #define SP(t, s, c) print(m, t, s, c, stdout)
128 #define AT(t, p1, p2, s1, s2) at(m, t, p1, p2, s1, s2)
129 #define NOTE(str) { if (m->eflags®_TRACE) printf("=%s\n", (str)); }
131 #define SP(t, s, c) /* nothing */
132 #define AT(t, p1, p2, s1, s2) /* nothing */
133 #define NOTE(s) /* nothing */
137 - matcher - the actual matching engine
138 == static int matcher(struct re_guts *g, char *string, \
139 == size_t nmatch, regmatch_t pmatch[], int eflags);
141 static int /* 0 success, REG_NOMATCH failure */
142 matcher(struct re_guts *g, char *string, size_t nmatch, regmatch_t pmatch[],
148 struct match *m = &mv;
150 const sopno gf = g->firststate+1; /* +1 for OEND */
151 const sopno gl = g->laststate;
154 /* Boyer-Moore algorithms variables */
164 /* simplify the situation where possible */
165 if (g->cflags®_NOSUB)
167 if (eflags®_STARTEND) {
168 start = string + pmatch[0].rm_so;
169 stop = string + pmatch[0].rm_eo;
172 stop = start + strlen(start);
177 /* prescreening; this does wonders for this rather slow code */
178 if (g->must != NULL) {
179 if (g->charjump != NULL && g->matchjump != NULL) {
181 mustlast = g->must + g->mlen - 1;
182 charjump = g->charjump;
183 matchjump = g->matchjump;
185 for (dp = start+g->mlen-1; dp < stop;) {
186 /* Fast skip non-matches */
187 while (dp < stop && charjump[*dp])
194 /* We depend on not being used for
195 * for strings of length 1
197 while (*--dp == *--pp && pp != mustfirst);
202 /* Jump to next possible match */
203 mj = matchjump[pp - mustfirst];
205 dp += (cj < mj ? mj : cj);
211 for (dp = start; dp < stop; dp++)
212 if (*dp == g->must[0] &&
213 stop - dp >= g->mlen &&
214 memcmp(dp, g->must, (size_t)g->mlen) == 0)
216 if (dp == stop) /* we didn't find g->must */
221 /* match struct setup */
236 /* Adjust start according to moffset, to speed things up */
238 start = ((dp - g->moffset) < start) ? start : dp - g->moffset;
240 /* this loop does only one repetition except for backrefs */
242 endp = fast(m, start, stop, gf, gl);
243 if (endp == NULL) { /* a miss */
244 if (m->pmatch != NULL)
245 free((char *)m->pmatch);
246 if (m->lastpos != NULL)
247 free((char *)m->lastpos);
251 if (nmatch == 0 && !g->backrefs)
252 break; /* no further info needed */
255 assert(m->coldp != NULL);
257 NOTE("finding start");
258 endp = slow(m, m->coldp, stop, gf, gl);
261 assert(m->coldp < m->endp);
264 if (nmatch == 1 && !g->backrefs)
265 break; /* no further info needed */
267 /* oh my, he wants the subexpressions... */
268 if (m->pmatch == NULL)
269 m->pmatch = (regmatch_t *)malloc((m->g->nsub + 1) *
271 if (m->pmatch == NULL) {
275 for (i = 1; i <= m->g->nsub; i++)
276 m->pmatch[i].rm_so = m->pmatch[i].rm_eo = -1;
277 if (!g->backrefs && !(m->eflags®_BACKR)) {
279 dp = dissect(m, m->coldp, endp, gf, gl);
281 if (g->nplus > 0 && m->lastpos == NULL)
282 m->lastpos = (char **)malloc((g->nplus+1) *
284 if (g->nplus > 0 && m->lastpos == NULL) {
289 NOTE("backref dissect");
290 dp = backref(m, m->coldp, endp, gf, gl, (sopno)0);
295 /* uh-oh... we couldn't find a subexpression-level match */
296 assert(g->backrefs); /* must be back references doing it */
297 assert(g->nplus == 0 || m->lastpos != NULL);
299 if (dp != NULL || endp <= m->coldp)
302 endp = slow(m, m->coldp, endp-1, gf, gl);
305 /* try it on a shorter possibility */
307 for (i = 1; i <= m->g->nsub; i++) {
308 assert(m->pmatch[i].rm_so == -1);
309 assert(m->pmatch[i].rm_eo == -1);
312 NOTE("backoff dissect");
313 dp = backref(m, m->coldp, endp, gf, gl, (sopno)0);
315 assert(dp == NULL || dp == endp);
316 if (dp != NULL) /* found a shorter one */
319 /* despite initial appearances, there is no match here */
321 start = m->coldp + 1; /* recycle starting later */
322 assert(start <= stop);
325 /* fill in the details if requested */
327 pmatch[0].rm_so = m->coldp - m->offp;
328 pmatch[0].rm_eo = endp - m->offp;
331 assert(m->pmatch != NULL);
332 for (i = 1; i < nmatch; i++)
334 pmatch[i] = m->pmatch[i];
336 pmatch[i].rm_so = -1;
337 pmatch[i].rm_eo = -1;
341 if (m->pmatch != NULL)
342 free((char *)m->pmatch);
343 if (m->lastpos != NULL)
344 free((char *)m->lastpos);
350 - dissect - figure out what matched what, no back references
351 == static char *dissect(struct match *m, char *start, \
352 == char *stop, sopno startst, sopno stopst);
354 static char * /* == stop (success) always */
355 dissect(struct match *m, char *start, char *stop, sopno startst, sopno stopst)
358 sopno ss; /* start sop of current subRE */
359 sopno es; /* end sop of current subRE */
360 char *sp; /* start of string matched by it */
361 char *stp; /* string matched by it cannot pass here */
362 char *rest; /* start of rest of string */
363 char *tail; /* string unmatched by rest of RE */
364 sopno ssub; /* start sop of subsubRE */
365 sopno esub; /* end sop of subsubRE */
366 char *ssp; /* start of string matched by subsubRE */
367 char *sep; /* end of string matched by subsubRE */
368 char *oldssp; /* previous ssp */
371 AT("diss", start, stop, startst, stopst);
373 for (ss = startst; ss < stopst; ss = es) {
374 /* identify end of subRE */
376 switch (OP(m->g->strip[es])) {
379 es += OPND(m->g->strip[es]);
382 while (OP(m->g->strip[es]) != O_CH)
383 es += OPND(m->g->strip[es]);
388 /* figure out what it matched */
389 switch (OP(m->g->strip[ss])) {
409 /* cases where length of match is hard to find */
413 /* how long could this one be? */
414 rest = slow(m, sp, stp, ss, es);
415 assert(rest != NULL); /* it did match */
416 /* could the rest match the rest? */
417 tail = slow(m, rest, stop, es, stopst);
420 /* no -- try a shorter match for this one */
422 assert(stp >= sp); /* it did work */
426 /* did innards match? */
427 if (slow(m, sp, rest, ssub, esub) != NULL) {
428 dp = dissect(m, sp, rest, ssub, esub);
437 /* how long could this one be? */
438 rest = slow(m, sp, stp, ss, es);
439 assert(rest != NULL); /* it did match */
440 /* could the rest match the rest? */
441 tail = slow(m, rest, stop, es, stopst);
444 /* no -- try a shorter match for this one */
446 assert(stp >= sp); /* it did work */
452 for (;;) { /* find last match of innards */
453 sep = slow(m, ssp, rest, ssub, esub);
454 if (sep == NULL || sep == ssp)
455 break; /* failed or matched null */
456 oldssp = ssp; /* on to next try */
460 /* last successful match */
464 assert(sep == rest); /* must exhaust substring */
465 assert(slow(m, ssp, sep, ssub, esub) == rest);
466 dp = dissect(m, ssp, sep, ssub, esub);
473 /* how long could this one be? */
474 rest = slow(m, sp, stp, ss, es);
475 assert(rest != NULL); /* it did match */
476 /* could the rest match the rest? */
477 tail = slow(m, rest, stop, es, stopst);
480 /* no -- try a shorter match for this one */
482 assert(stp >= sp); /* it did work */
485 esub = ss + OPND(m->g->strip[ss]) - 1;
486 assert(OP(m->g->strip[esub]) == OOR1);
487 for (;;) { /* find first matching branch */
488 if (slow(m, sp, rest, ssub, esub) == rest)
489 break; /* it matched all of it */
490 /* that one missed, try next one */
491 assert(OP(m->g->strip[esub]) == OOR1);
493 assert(OP(m->g->strip[esub]) == OOR2);
495 esub += OPND(m->g->strip[esub]);
496 if (OP(m->g->strip[esub]) == OOR2)
499 assert(OP(m->g->strip[esub]) == O_CH);
501 dp = dissect(m, sp, rest, ssub, esub);
513 i = OPND(m->g->strip[ss]);
514 assert(0 < i && i <= m->g->nsub);
515 m->pmatch[i].rm_so = sp - m->offp;
518 i = OPND(m->g->strip[ss]);
519 assert(0 < i && i <= m->g->nsub);
520 m->pmatch[i].rm_eo = sp - m->offp;
533 - backref - figure out what matched what, figuring in back references
534 == static char *backref(struct match *m, char *start, \
535 == char *stop, sopno startst, sopno stopst, sopno lev);
537 static char * /* == stop (success) or NULL (failure) */
538 backref(struct match *m, char *start, char *stop, sopno startst, sopno stopst,
539 sopno lev) /* PLUS nesting level */
542 sopno ss; /* start sop of current subRE */
543 char *sp; /* start of string matched by it */
544 sopno ssub; /* start sop of subsubRE */
545 sopno esub; /* end sop of subsubRE */
546 char *ssp; /* start of string matched by subsubRE */
554 AT("back", start, stop, startst, stopst);
557 /* get as far as we can with easy stuff */
559 for (ss = startst; !hard && ss < stopst; ss++)
560 switch (OP(s = m->g->strip[ss])) {
562 if (sp == stop || *sp++ != (char)OPND(s))
571 cs = &m->g->sets[OPND(s)];
572 if (sp == stop || !CHIN(cs, *sp++))
576 if ( (sp == m->beginp && !(m->eflags®_NOTBOL)) ||
577 (sp < m->endp && *(sp-1) == '\n' &&
578 (m->g->cflags®_NEWLINE)) )
584 if ( (sp == m->endp && !(m->eflags®_NOTEOL)) ||
585 (sp < m->endp && *sp == '\n' &&
586 (m->g->cflags®_NEWLINE)) )
592 if (( (sp == m->beginp && !(m->eflags®_NOTBOL)) ||
593 (sp < m->endp && *(sp-1) == '\n' &&
594 (m->g->cflags®_NEWLINE)) ||
596 !ISWORD(*(sp-1))) ) &&
597 (sp < m->endp && ISWORD(*sp)) )
603 if (( (sp == m->endp && !(m->eflags®_NOTEOL)) ||
604 (sp < m->endp && *sp == '\n' &&
605 (m->g->cflags®_NEWLINE)) ||
606 (sp < m->endp && !ISWORD(*sp)) ) &&
607 (sp > m->beginp && ISWORD(*(sp-1))) )
614 case OOR1: /* matches null but needs to skip */
618 assert(OP(s) == OOR2);
620 } while (OP(s = m->g->strip[ss]) != O_CH);
621 /* note that the ss++ gets us past the O_CH */
623 default: /* have to make a choice */
627 if (!hard) { /* that was it! */
632 ss--; /* adjust for the for's final increment */
635 AT("hard", sp, stop, ss, stopst);
638 case OBACK_: /* the vilest depths */
640 assert(0 < i && i <= m->g->nsub);
641 if (m->pmatch[i].rm_eo == -1)
643 assert(m->pmatch[i].rm_so != -1);
644 len = m->pmatch[i].rm_eo - m->pmatch[i].rm_so;
645 assert(stop - m->beginp >= len);
647 return(NULL); /* not enough left to match */
648 ssp = m->offp + m->pmatch[i].rm_so;
649 if (memcmp(sp, ssp, len) != 0)
651 while (m->g->strip[ss] != SOP(O_BACK, i))
653 return(backref(m, sp+len, stop, ss+1, stopst, lev));
655 case OQUEST_: /* to null or not */
656 dp = backref(m, sp, stop, ss+1, stopst, lev);
658 return(dp); /* not */
659 return(backref(m, sp, stop, ss+OPND(s)+1, stopst, lev));
662 assert(m->lastpos != NULL);
663 assert(lev+1 <= m->g->nplus);
664 m->lastpos[lev+1] = sp;
665 return(backref(m, sp, stop, ss+1, stopst, lev+1));
668 if (sp == m->lastpos[lev]) /* last pass matched null */
669 return(backref(m, sp, stop, ss+1, stopst, lev-1));
670 /* try another pass */
671 m->lastpos[lev] = sp;
672 dp = backref(m, sp, stop, ss-OPND(s)+1, stopst, lev);
674 return(backref(m, sp, stop, ss+1, stopst, lev-1));
678 case OCH_: /* find the right one, if any */
680 esub = ss + OPND(s) - 1;
681 assert(OP(m->g->strip[esub]) == OOR1);
682 for (;;) { /* find first matching branch */
683 dp = backref(m, sp, stop, ssub, esub, lev);
686 /* that one missed, try next one */
687 if (OP(m->g->strip[esub]) == O_CH)
688 return(NULL); /* there is none */
690 assert(OP(m->g->strip[esub]) == OOR2);
692 esub += OPND(m->g->strip[esub]);
693 if (OP(m->g->strip[esub]) == OOR2)
696 assert(OP(m->g->strip[esub]) == O_CH);
699 case OLPAREN: /* must undo assignment if rest fails */
701 assert(0 < i && i <= m->g->nsub);
702 offsave = m->pmatch[i].rm_so;
703 m->pmatch[i].rm_so = sp - m->offp;
704 dp = backref(m, sp, stop, ss+1, stopst, lev);
707 m->pmatch[i].rm_so = offsave;
710 case ORPAREN: /* must undo assignment if rest fails */
712 assert(0 < i && i <= m->g->nsub);
713 offsave = m->pmatch[i].rm_eo;
714 m->pmatch[i].rm_eo = sp - m->offp;
715 dp = backref(m, sp, stop, ss+1, stopst, lev);
718 m->pmatch[i].rm_eo = offsave;
729 return "shut up gcc";
733 - fast - step through the string at top speed
734 == static char *fast(struct match *m, char *start, \
735 == char *stop, sopno startst, sopno stopst);
737 static char * /* where tentative match ended, or NULL */
738 fast(struct match *m, char *start, char *stop, sopno startst, sopno stopst)
741 states fresh = m->fresh;
744 int c = (start == m->beginp) ? OUT : *(start-1);
745 int lastc; /* previous c */
748 char *coldp; /* last p after which no match was underway */
752 st = step(m->g, startst, stopst, st, NOTHING, st);
759 c = (p == m->endp) ? OUT : *p;
763 /* is there an EOL and/or BOL between lastc and c? */
766 if ( (lastc == '\n' && m->g->cflags®_NEWLINE) ||
767 (lastc == OUT && !(m->eflags®_NOTBOL)) ) {
771 if ( (c == '\n' && m->g->cflags®_NEWLINE) ||
772 (c == OUT && !(m->eflags®_NOTEOL)) ) {
773 flagch = (flagch == BOL) ? BOLEOL : EOL;
778 st = step(m->g, startst, stopst, st, flagch, st);
782 /* how about a word boundary? */
783 if ( (flagch == BOL || (lastc != OUT && !ISWORD(lastc))) &&
784 (c != OUT && ISWORD(c)) ) {
787 if ( (lastc != OUT && ISWORD(lastc)) &&
788 (flagch == EOL || (c != OUT && !ISWORD(c))) ) {
791 if (flagch == BOW || flagch == EOW) {
792 st = step(m->g, startst, stopst, st, flagch, st);
797 if (ISSET(st, stopst) || p == stop)
798 break; /* NOTE BREAK OUT */
800 /* no, we must deal with this character */
804 st = step(m->g, startst, stopst, tmp, c, st);
806 assert(EQ(step(m->g, startst, stopst, st, NOTHING, st), st));
810 assert(coldp != NULL);
812 if (ISSET(st, stopst))
819 - slow - step through the string more deliberately
820 == static char *slow(struct match *m, char *start, \
821 == char *stop, sopno startst, sopno stopst);
823 static char * /* where it ended */
824 slow(struct match *m, char *start, char *stop, sopno startst, sopno stopst)
827 states empty = m->empty;
830 int c = (start == m->beginp) ? OUT : *(start-1);
831 int lastc; /* previous c */
834 char *matchp; /* last p at which a match ended */
836 AT("slow", start, stop, startst, stopst);
839 SP("sstart", st, *p);
840 st = step(m->g, startst, stopst, st, NOTHING, st);
845 c = (p == m->endp) ? OUT : *p;
847 /* is there an EOL and/or BOL between lastc and c? */
850 if ( (lastc == '\n' && m->g->cflags®_NEWLINE) ||
851 (lastc == OUT && !(m->eflags®_NOTBOL)) ) {
855 if ( (c == '\n' && m->g->cflags®_NEWLINE) ||
856 (c == OUT && !(m->eflags®_NOTEOL)) ) {
857 flagch = (flagch == BOL) ? BOLEOL : EOL;
862 st = step(m->g, startst, stopst, st, flagch, st);
863 SP("sboleol", st, c);
866 /* how about a word boundary? */
867 if ( (flagch == BOL || (lastc != OUT && !ISWORD(lastc))) &&
868 (c != OUT && ISWORD(c)) ) {
871 if ( (lastc != OUT && ISWORD(lastc)) &&
872 (flagch == EOL || (c != OUT && !ISWORD(c))) ) {
875 if (flagch == BOW || flagch == EOW) {
876 st = step(m->g, startst, stopst, st, flagch, st);
877 SP("sboweow", st, c);
881 if (ISSET(st, stopst))
883 if (EQ(st, empty) || p == stop)
884 break; /* NOTE BREAK OUT */
886 /* no, we must deal with this character */
890 st = step(m->g, startst, stopst, tmp, c, st);
892 assert(EQ(step(m->g, startst, stopst, st, NOTHING, st), st));
901 - step - map set of states reachable before char to set reachable after
902 == static states step(struct re_guts *g, sopno start, sopno stop, \
903 == states bef, int ch, states aft);
904 == #define BOL (OUT+1)
905 == #define EOL (BOL+1)
906 == #define BOLEOL (BOL+2)
907 == #define NOTHING (BOL+3)
908 == #define BOW (BOL+4)
909 == #define EOW (BOL+5)
910 == #define CODEMAX (BOL+5) // highest code used
911 == #define NONCHAR(c) ((c) > CHAR_MAX)
912 == #define NNONCHAR (CODEMAX-CHAR_MAX)
915 step(struct re_guts *g,
916 sopno start, /* start state within strip */
917 sopno stop, /* state after stop state within strip */
918 states bef, /* states reachable before */
919 int ch, /* character or NONCHAR code */
920 states aft) /* states already known reachable after */
925 onestate here; /* note, macros know this name */
929 for (pc = start, INIT(here, pc); pc != stop; pc++, INC(here)) {
933 assert(pc == stop-1);
936 /* only characters can match */
937 assert(!NONCHAR(ch) || ch != (char)OPND(s));
938 if (ch == (char)OPND(s))
942 if (ch == BOL || ch == BOLEOL)
946 if (ch == EOL || ch == BOLEOL)
962 cs = &g->sets[OPND(s)];
963 if (!NONCHAR(ch) && CHIN(cs, ch))
966 case OBACK_: /* ignored here */
970 case OPLUS_: /* forward, this is just an empty */
973 case O_PLUS: /* both forward and back */
975 i = ISSETBACK(aft, OPND(s));
976 BACK(aft, aft, OPND(s));
977 if (!i && ISSETBACK(aft, OPND(s))) {
978 /* oho, must reconsider loop body */
983 case OQUEST_: /* two branches, both forward */
985 FWD(aft, aft, OPND(s));
987 case O_QUEST: /* just an empty */
990 case OLPAREN: /* not significant here */
994 case OCH_: /* mark the first two branches */
996 assert(OP(g->strip[pc+OPND(s)]) == OOR2);
997 FWD(aft, aft, OPND(s));
999 case OOR1: /* done a branch, find the O_CH */
1000 if (ISSTATEIN(aft, here)) {
1002 OP(s = g->strip[pc+look]) != O_CH;
1004 assert(OP(s) == OOR2);
1005 FWD(aft, aft, look);
1008 case OOR2: /* propagate OCH_'s marking */
1010 if (OP(g->strip[pc+OPND(s)]) != O_CH) {
1011 assert(OP(g->strip[pc+OPND(s)]) == OOR2);
1012 FWD(aft, aft, OPND(s));
1015 case O_CH: /* just empty */
1018 default: /* ooooops... */
1029 - print - print a set of states
1031 == static void print(struct match *m, char *caption, states st, \
1032 == int ch, FILE *d);
1036 print(struct match *m, char *caption, states st, int ch, FILE *d)
1038 struct re_guts *g = m->g;
1042 if (!(m->eflags®_TRACE))
1045 fprintf(d, "%s", caption);
1047 fprintf(d, " %s", pchar(ch));
1048 for (i = 0; i < g->nstates; i++)
1050 fprintf(d, "%s%d", (first) ? "\t" : ", ", i);
1057 - at - print current situation
1059 == static void at(struct match *m, char *title, char *start, char *stop, \
1060 == sopno startst, sopno stopst);
1064 at(struct match *m, char *title, char *start, char *stop, sopno startst,
1067 if (!(m->eflags®_TRACE))
1070 printf("%s %s-", title, pchar(*start));
1071 printf("%s ", pchar(*stop));
1072 printf("%ld-%ld\n", (long)startst, (long)stopst);
1076 #define PCHARDONE /* never again */
1078 - pchar - make a character printable
1080 == static char *pchar(int ch);
1083 * Is this identical to regchar() over in debug.c? Well, yes. But a
1084 * duplicate here avoids having a debugging-capable regexec.o tied to
1085 * a matching debug.o, and this is convenient. It all disappears in
1086 * the non-debug compilation anyway, so it doesn't matter much.
1088 static char * /* -> representation */
1091 static char pbuf[10];
1093 if (isprint((uch)ch) || ch == ' ')
1094 sprintf(pbuf, "%c", ch);
1096 sprintf(pbuf, "\\%o", ch);