2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1992, 1993, 1994 Henry Spencer.
5 * Copyright (c) 1992, 1993, 1994
6 * The Regents of the University of California. All rights reserved.
8 * This code is derived from software contributed to Berkeley by
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * @(#)engine.c 8.5 (Berkeley) 3/20/94
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
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
53 #define dissect sdissect
54 #define backref sbackref
61 #define matcher lmatcher
63 #define dissect ldissect
64 #define backref lbackref
71 #define matcher mmatcher
73 #define dissect mdissect
74 #define backref mbackref
81 /* another structure passed up and down to avoid zillions of parameters */
85 regmatch_t *pmatch; /* [nsub+1] (0 element unused) */
86 const char *offp; /* offsets work from here */
87 const char *beginp; /* start of string -- virtual NUL precedes */
88 const char *endp; /* end of string -- virtual NUL here */
89 const char *coldp; /* can be no match starting before here */
90 const char **lastpos; /* [nplus+1] */
92 states st; /* current states */
93 states fresh; /* states for a fresh start */
94 states tmp; /* temporary */
95 states empty; /* empty set of states */
96 mbstate_t mbs; /* multibyte conversion state */
99 /* ========= begin header generated by ./mkh ========= */
104 /* === engine.c === */
105 static int matcher(struct re_guts *g, const char *string, size_t nmatch, regmatch_t pmatch[], int eflags);
106 static const char *dissect(struct match *m, const char *start, const char *stop, sopno startst, sopno stopst);
107 static const char *backref(struct match *m, const char *start, const char *stop, sopno startst, sopno stopst, sopno lev, int);
108 static const char *walk(struct match *m, const char *start, const char *stop, sopno startst, sopno stopst, bool fast);
109 static states step(struct re_guts *g, sopno start, sopno stop, states bef, wint_t ch, states aft);
110 #define MAX_RECURSION 100
113 #define BOLEOL (BOL-2)
114 #define NOTHING (BOL-3)
117 #define BADCHAR (BOL-6)
118 #define NONCHAR(c) ((c) <= OUT)
120 static void print(struct match *m, const char *caption, states st, int ch, FILE *d);
123 static void at(struct match *m, const char *title, const char *start, const char *stop, sopno startst, sopno stopst);
126 static const char *pchar(int ch);
132 /* ========= end header generated by ./mkh ========= */
135 #define SP(t, s, c) print(m, t, s, c, stdout)
136 #define AT(t, p1, p2, s1, s2) at(m, t, p1, p2, s1, s2)
137 #define NOTE(str) { if (m->eflags®_TRACE) printf("=%s\n", (str)); }
139 #define SP(t, s, c) /* nothing */
140 #define AT(t, p1, p2, s1, s2) /* nothing */
141 #define NOTE(s) /* nothing */
145 - matcher - the actual matching engine
146 == static int matcher(struct re_guts *g, const char *string, \
147 == size_t nmatch, regmatch_t pmatch[], int eflags);
149 static int /* 0 success, REG_NOMATCH failure */
150 matcher(struct re_guts *g,
159 struct match *m = &mv;
160 const char *dp = NULL;
161 const sopno gf = g->firststate+1; /* +1 for OEND */
162 const sopno gl = g->laststate;
165 /* Boyer-Moore algorithms variables */
168 const char *mustfirst;
169 const char *mustlast;
173 /* simplify the situation where possible */
174 if (g->cflags®_NOSUB)
176 if (eflags®_STARTEND) {
177 start = string + pmatch[0].rm_so;
178 stop = string + pmatch[0].rm_eo;
181 stop = start + strlen(start);
186 /* prescreening; this does wonders for this rather slow code */
187 if (g->must != NULL) {
188 if (g->charjump != NULL && g->matchjump != NULL) {
190 mustlast = g->must + g->mlen - 1;
191 charjump = g->charjump;
192 matchjump = g->matchjump;
194 for (dp = start+g->mlen-1; dp < stop;) {
195 /* Fast skip non-matches */
196 while (dp < stop && charjump[(int)*dp])
197 dp += charjump[(int)*dp];
203 /* We depend on not being used for
204 * for strings of length 1
206 while (*--dp == *--pp && pp != mustfirst);
211 /* Jump to next possible match */
212 mj = matchjump[pp - mustfirst];
213 cj = charjump[(int)*dp];
214 dp += (cj < mj ? mj : cj);
220 for (dp = start; dp < stop; dp++)
221 if (*dp == g->must[0] &&
222 stop - dp >= g->mlen &&
223 memcmp(dp, g->must, (size_t)g->mlen) == 0)
225 if (dp == stop) /* we didn't find g->must */
230 /* match struct setup */
246 /* Adjust start according to moffset, to speed things up */
247 if (dp != NULL && g->moffset > -1)
248 start = ((dp - g->moffset) < start) ? start : dp - g->moffset;
250 SP("mloop", m->st, *start);
252 /* this loop does only one repetition except for backrefs */
254 endp = walk(m, start, stop, gf, gl, true);
255 if (endp == NULL) { /* a miss */
256 if (m->pmatch != NULL)
257 free((char *)m->pmatch);
258 if (m->lastpos != NULL)
259 free((char *)m->lastpos);
263 if (nmatch == 0 && !g->backrefs)
264 break; /* no further info needed */
267 assert(m->coldp != NULL);
269 NOTE("finding start");
270 endp = walk(m, m->coldp, stop, gf, gl, false);
273 assert(m->coldp < m->endp);
274 m->coldp += XMBRTOWC(NULL, m->coldp,
275 m->endp - m->coldp, &m->mbs, 0);
277 if (nmatch == 1 && !g->backrefs)
278 break; /* no further info needed */
280 /* oh my, he wants the subexpressions... */
281 if (m->pmatch == NULL)
282 m->pmatch = (regmatch_t *)malloc((m->g->nsub + 1) *
284 if (m->pmatch == NULL) {
288 for (i = 1; i <= m->g->nsub; i++)
289 m->pmatch[i].rm_so = m->pmatch[i].rm_eo = -1;
290 if (!g->backrefs && !(m->eflags®_BACKR)) {
292 dp = dissect(m, m->coldp, endp, gf, gl);
294 if (g->nplus > 0 && m->lastpos == NULL)
295 m->lastpos = malloc((g->nplus+1) *
296 sizeof(const char *));
297 if (g->nplus > 0 && m->lastpos == NULL) {
302 NOTE("backref dissect");
303 dp = backref(m, m->coldp, endp, gf, gl, (sopno)0, 0);
308 /* uh-oh... we couldn't find a subexpression-level match */
309 assert(g->backrefs); /* must be back references doing it */
310 assert(g->nplus == 0 || m->lastpos != NULL);
312 if (dp != NULL || endp <= m->coldp)
315 endp = walk(m, m->coldp, endp-1, gf, gl, false);
318 /* try it on a shorter possibility */
320 for (i = 1; i <= m->g->nsub; i++) {
321 assert(m->pmatch[i].rm_so == -1);
322 assert(m->pmatch[i].rm_eo == -1);
325 NOTE("backoff dissect");
326 dp = backref(m, m->coldp, endp, gf, gl, (sopno)0, 0);
328 assert(dp == NULL || dp == endp);
329 if (dp != NULL) /* found a shorter one */
332 /* despite initial appearances, there is no match here */
334 /* recycle starting later */
335 start = m->coldp + XMBRTOWC(NULL, m->coldp,
336 stop - m->coldp, &m->mbs, 0);
337 assert(start <= stop);
340 /* fill in the details if requested */
342 pmatch[0].rm_so = m->coldp - m->offp;
343 pmatch[0].rm_eo = endp - m->offp;
346 assert(m->pmatch != NULL);
347 for (i = 1; i < nmatch; i++)
349 pmatch[i] = m->pmatch[i];
351 pmatch[i].rm_so = -1;
352 pmatch[i].rm_eo = -1;
356 if (m->pmatch != NULL)
357 free((char *)m->pmatch);
358 if (m->lastpos != NULL)
359 free((char *)m->lastpos);
365 - dissect - figure out what matched what, no back references
366 == static const char *dissect(struct match *m, const char *start, \
367 == const char *stop, sopno startst, sopno stopst);
369 static const char * /* == stop (success) always */
370 dissect(struct match *m,
377 sopno ss; /* start sop of current subRE */
378 sopno es; /* end sop of current subRE */
379 const char *sp; /* start of string matched by it */
380 const char *stp; /* string matched by it cannot pass here */
381 const char *rest; /* start of rest of string */
382 const char *tail; /* string unmatched by rest of RE */
383 sopno ssub; /* start sop of subsubRE */
384 sopno esub; /* end sop of subsubRE */
385 const char *ssp; /* start of string matched by subsubRE */
386 const char *sep; /* end of string matched by subsubRE */
387 const char *oldssp; /* previous ssp */
390 AT("diss", start, stop, startst, stopst);
392 for (ss = startst; ss < stopst; ss = es) {
393 /* identify end of subRE */
395 switch (OP(m->g->strip[es])) {
398 es += OPND(m->g->strip[es]);
401 while (OP(m->g->strip[es]) != (sop)O_CH)
402 es += OPND(m->g->strip[es]);
407 /* figure out what it matched */
408 switch (OP(m->g->strip[ss])) {
413 sp += XMBRTOWC(NULL, sp, stop - start, &m->mbs, 0);
422 sp += XMBRTOWC(NULL, sp, stop - start, &m->mbs, 0);
428 /* cases where length of match is hard to find */
432 /* how long could this one be? */
433 rest = walk(m, sp, stp, ss, es, false);
434 assert(rest != NULL); /* it did match */
435 /* could the rest match the rest? */
436 tail = walk(m, rest, stop, es, stopst, false);
439 /* no -- try a shorter match for this one */
441 assert(stp >= sp); /* it did work */
445 /* did innards match? */
446 if (walk(m, sp, rest, ssub, esub, false) != NULL) {
447 dp = dissect(m, sp, rest, ssub, esub);
456 /* how long could this one be? */
457 rest = walk(m, sp, stp, ss, es, false);
458 assert(rest != NULL); /* it did match */
459 /* could the rest match the rest? */
460 tail = walk(m, rest, stop, es, stopst, false);
463 /* no -- try a shorter match for this one */
465 assert(stp >= sp); /* it did work */
471 for (;;) { /* find last match of innards */
472 sep = walk(m, ssp, rest, ssub, esub, false);
473 if (sep == NULL || sep == ssp)
474 break; /* failed or matched null */
475 oldssp = ssp; /* on to next try */
479 /* last successful match */
483 assert(sep == rest); /* must exhaust substring */
484 assert(walk(m, ssp, sep, ssub, esub, false) == rest);
485 dp = dissect(m, ssp, sep, ssub, esub);
492 /* how long could this one be? */
493 rest = walk(m, sp, stp, ss, es, false);
494 assert(rest != NULL); /* it did match */
495 /* could the rest match the rest? */
496 tail = walk(m, rest, stop, es, stopst, false);
499 /* no -- try a shorter match for this one */
501 assert(stp >= sp); /* it did work */
504 esub = ss + OPND(m->g->strip[ss]) - 1;
505 assert(OP(m->g->strip[esub]) == OOR1);
506 for (;;) { /* find first matching branch */
507 if (walk(m, sp, rest, ssub, esub, false) == rest)
508 break; /* it matched all of it */
509 /* that one missed, try next one */
510 assert(OP(m->g->strip[esub]) == OOR1);
512 assert(OP(m->g->strip[esub]) == OOR2);
514 esub += OPND(m->g->strip[esub]);
515 if (OP(m->g->strip[esub]) == (sop)OOR2)
518 assert(OP(m->g->strip[esub]) == O_CH);
520 dp = dissect(m, sp, rest, ssub, esub);
532 i = OPND(m->g->strip[ss]);
533 assert(0 < i && i <= m->g->nsub);
534 m->pmatch[i].rm_so = sp - m->offp;
537 i = OPND(m->g->strip[ss]);
538 assert(0 < i && i <= m->g->nsub);
539 m->pmatch[i].rm_eo = sp - m->offp;
552 - backref - figure out what matched what, figuring in back references
553 == static const char *backref(struct match *m, const char *start, \
554 == const char *stop, sopno startst, sopno stopst, sopno lev);
556 static const char * /* == stop (success) or NULL (failure) */
557 backref(struct match *m,
562 sopno lev, /* PLUS nesting level */
566 sopno ss; /* start sop of current subRE */
567 const char *sp; /* start of string matched by it */
568 sopno ssub; /* start sop of subsubRE */
569 sopno esub; /* end sop of subsubRE */
570 const char *ssp; /* start of string matched by subsubRE */
579 AT("back", start, stop, startst, stopst);
582 /* get as far as we can with easy stuff */
584 for (ss = startst; !hard && ss < stopst; ss++)
585 switch (OP(s = m->g->strip[ss])) {
589 sp += XMBRTOWC(&wc, sp, stop - sp, &m->mbs, BADCHAR);
596 sp += XMBRTOWC(&wc, sp, stop - sp, &m->mbs, BADCHAR);
603 cs = &m->g->sets[OPND(s)];
604 sp += XMBRTOWC(&wc, sp, stop - sp, &m->mbs, BADCHAR);
605 if (wc == BADCHAR || !CHIN(cs, wc))
609 if ((sp == m->beginp && !(m->eflags®_NOTBOL)) ||
610 (sp > m->offp && sp < m->endp &&
611 *(sp-1) == '\n' && (m->g->cflags®_NEWLINE)))
617 if ( (sp == m->endp && !(m->eflags®_NOTEOL)) ||
618 (sp < m->endp && *sp == '\n' &&
619 (m->g->cflags®_NEWLINE)) )
625 if (sp < m->endp && ISWORD(*sp) &&
626 ((sp == m->beginp && !(m->eflags®_NOTBOL)) ||
627 (sp > m->offp && !ISWORD(*(sp-1)))))
633 if (( (sp == m->endp && !(m->eflags®_NOTEOL)) ||
634 (sp < m->endp && *sp == '\n' &&
635 (m->g->cflags®_NEWLINE)) ||
636 (sp < m->endp && !ISWORD(*sp)) ) &&
637 (sp > m->beginp && ISWORD(*(sp-1))) )
644 case OOR1: /* matches null but needs to skip */
648 assert(OP(s) == OOR2);
650 } while (OP(s = m->g->strip[ss]) != (sop)O_CH);
651 /* note that the ss++ gets us past the O_CH */
653 default: /* have to make a choice */
657 if (!hard) { /* that was it! */
662 ss--; /* adjust for the for's final increment */
665 AT("hard", sp, stop, ss, stopst);
668 case OBACK_: /* the vilest depths */
670 assert(0 < i && i <= m->g->nsub);
671 if (m->pmatch[i].rm_eo == -1)
673 assert(m->pmatch[i].rm_so != -1);
674 len = m->pmatch[i].rm_eo - m->pmatch[i].rm_so;
675 if (len == 0 && rec++ > MAX_RECURSION)
677 assert(stop - m->beginp >= len);
679 return(NULL); /* not enough left to match */
680 ssp = m->offp + m->pmatch[i].rm_so;
681 if (memcmp(sp, ssp, len) != 0)
683 while (m->g->strip[ss] != (sop)SOP(O_BACK, i))
685 return(backref(m, sp+len, stop, ss+1, stopst, lev, rec));
686 case OQUEST_: /* to null or not */
687 dp = backref(m, sp, stop, ss+1, stopst, lev, rec);
689 return(dp); /* not */
690 return(backref(m, sp, stop, ss+OPND(s)+1, stopst, lev, rec));
692 assert(m->lastpos != NULL);
693 assert(lev+1 <= m->g->nplus);
694 m->lastpos[lev+1] = sp;
695 return(backref(m, sp, stop, ss+1, stopst, lev+1, rec));
697 if (sp == m->lastpos[lev]) /* last pass matched null */
698 return(backref(m, sp, stop, ss+1, stopst, lev-1, rec));
699 /* try another pass */
700 m->lastpos[lev] = sp;
701 dp = backref(m, sp, stop, ss-OPND(s)+1, stopst, lev, rec);
703 return(backref(m, sp, stop, ss+1, stopst, lev-1, rec));
706 case OCH_: /* find the right one, if any */
708 esub = ss + OPND(s) - 1;
709 assert(OP(m->g->strip[esub]) == OOR1);
710 for (;;) { /* find first matching branch */
711 dp = backref(m, sp, stop, ssub, esub, lev, rec);
714 /* that one missed, try next one */
715 if (OP(m->g->strip[esub]) == (sop)O_CH)
716 return(NULL); /* there is none */
718 assert(OP(m->g->strip[esub]) == (sop)OOR2);
720 esub += OPND(m->g->strip[esub]);
721 if (OP(m->g->strip[esub]) == (sop)OOR2)
724 assert(OP(m->g->strip[esub]) == O_CH);
728 case OLPAREN: /* must undo assignment if rest fails */
730 assert(0 < i && i <= m->g->nsub);
731 offsave = m->pmatch[i].rm_so;
732 m->pmatch[i].rm_so = sp - m->offp;
733 dp = backref(m, sp, stop, ss+1, stopst, lev, rec);
736 m->pmatch[i].rm_so = offsave;
738 case ORPAREN: /* must undo assignment if rest fails */
740 assert(0 < i && i <= m->g->nsub);
741 offsave = m->pmatch[i].rm_eo;
742 m->pmatch[i].rm_eo = sp - m->offp;
743 dp = backref(m, sp, stop, ss+1, stopst, lev, rec);
746 m->pmatch[i].rm_eo = offsave;
756 return "shut up gcc";
760 - walk - step through the string either quickly or slowly
761 == static const char *walk(struct match *m, const char *start, \
762 == const char *stop, sopno startst, sopno stopst, bool fast);
764 static const char * /* where it ended, or NULL */
765 walk(struct match *m, const char *start, const char *stop, sopno startst,
766 sopno stopst, bool fast)
769 states fresh = m->fresh;
770 states empty = m->empty;
772 const char *p = start;
774 wint_t lastc; /* previous c */
777 const char *matchp; /* last p at which a match ended */
780 AT("slow", start, stop, startst, stopst);
783 SP("sstart", st, *p);
784 st = step(m->g, startst, stopst, st, NOTHING, st);
788 if (start == m->offp || (start == m->beginp && !(m->eflags®_NOTBOL)))
792 * XXX Wrong if the previous character was multi-byte.
793 * Newline never is (in encodings supported by FreeBSD),
794 * so this only breaks the ISWORD tests below.
796 c = (uch)*(start - 1);
805 clen = XMBRTOWC(&c, p, m->endp - p, &m->mbs, BADCHAR);
807 if (fast && EQ(st, fresh))
810 /* is there an EOL and/or BOL between lastc and c? */
813 if ( (lastc == '\n' && m->g->cflags®_NEWLINE) ||
814 (lastc == OUT && !(m->eflags®_NOTBOL)) ) {
818 if ( (c == '\n' && m->g->cflags®_NEWLINE) ||
819 (c == OUT && !(m->eflags®_NOTEOL)) ) {
820 flagch = (flagch == BOL) ? BOLEOL : EOL;
825 st = step(m->g, startst, stopst, st, flagch, st);
826 SP("sboleol", st, c);
829 /* how about a word boundary? */
830 if ( (flagch == BOL || (lastc != OUT && !ISWORD(lastc))) &&
831 (c != OUT && ISWORD(c)) ) {
834 if ( (lastc != OUT && ISWORD(lastc)) &&
835 (flagch == EOL || (c != OUT && !ISWORD(c))) ) {
838 if (flagch == BOW || flagch == EOW) {
839 st = step(m->g, startst, stopst, st, flagch, st);
840 SP("sboweow", st, c);
844 if (ISSET(st, stopst)) {
850 if (EQ(st, empty) || p == stop || clen > (size_t)(stop - p))
851 break; /* NOTE BREAK OUT */
853 /* no, we must deal with this character */
860 st = step(m->g, startst, stopst, tmp, c, st);
862 assert(EQ(step(m->g, startst, stopst, st, NOTHING, st), st));
867 assert(matchp != NULL);
869 if (ISSET(st, stopst))
870 return (p + XMBRTOWC(NULL, p, stop - p, &m->mbs, 0));
878 - step - map set of states reachable before char to set reachable after
879 == static states step(struct re_guts *g, sopno start, sopno stop, \
880 == states bef, int ch, states aft);
881 == #define BOL (OUT-1)
882 == #define EOL (BOL-1)
883 == #define BOLEOL (BOL-2)
884 == #define NOTHING (BOL-3)
885 == #define BOW (BOL-4)
886 == #define EOW (BOL-5)
887 == #define BADCHAR (BOL-6)
888 == #define NONCHAR(c) ((c) <= OUT)
891 step(struct re_guts *g,
892 sopno start, /* start state within strip */
893 sopno stop, /* state after stop state within strip */
894 states bef, /* states reachable before */
895 wint_t ch, /* character or NONCHAR code */
896 states aft) /* states already known reachable after */
901 onestate here; /* note, macros know this name */
905 for (pc = start, INIT(here, pc); pc != stop; pc++, INC(here)) {
909 assert(pc == stop-1);
912 /* only characters can match */
913 assert(!NONCHAR(ch) || ch != OPND(s));
918 if (ch == BOL || ch == BOLEOL)
922 if (ch == EOL || ch == BOLEOL)
938 cs = &g->sets[OPND(s)];
939 if (!NONCHAR(ch) && CHIN(cs, ch))
942 case OBACK_: /* ignored here */
946 case OPLUS_: /* forward, this is just an empty */
949 case O_PLUS: /* both forward and back */
951 i = ISSETBACK(aft, OPND(s));
952 BACK(aft, aft, OPND(s));
953 if (!i && ISSETBACK(aft, OPND(s))) {
954 /* oho, must reconsider loop body */
959 case OQUEST_: /* two branches, both forward */
961 FWD(aft, aft, OPND(s));
963 case O_QUEST: /* just an empty */
966 case OLPAREN: /* not significant here */
970 case OCH_: /* mark the first two branches */
972 assert(OP(g->strip[pc+OPND(s)]) == (sop)OOR2);
973 FWD(aft, aft, OPND(s));
975 case OOR1: /* done a branch, find the O_CH */
976 if (ISSTATEIN(aft, here)) {
978 OP(s = g->strip[pc+look]) != (sop)O_CH;
980 assert(OP(s) == (sop)OOR2);
981 FWD(aft, aft, look + 1);
984 case OOR2: /* propagate OCH_'s marking */
986 if (OP(g->strip[pc+OPND(s)]) != (sop)O_CH) {
987 assert(OP(g->strip[pc+OPND(s)]) == (sop)OOR2);
988 FWD(aft, aft, OPND(s));
991 case O_CH: /* just empty */
994 default: /* ooooops... */
1005 - print - print a set of states
1007 == static void print(struct match *m, const char *caption, states st, \
1008 == int ch, FILE *d);
1012 print(struct match *m,
1013 const char *caption,
1018 struct re_guts *g = m->g;
1022 if (!(m->eflags®_TRACE))
1025 fprintf(d, "%s", caption);
1027 fprintf(d, " %s", pchar(ch));
1028 for (i = 0; i < g->nstates; i++)
1030 fprintf(d, "%s%d", (first) ? "\t" : ", ", i);
1037 - at - print current situation
1039 == static void at(struct match *m, const char *title, const char *start, \
1040 == const char *stop, sopno startst, sopno stopst);
1044 at( struct match *m,
1051 if (!(m->eflags®_TRACE))
1054 printf("%s %s-", title, pchar(*start));
1055 printf("%s ", pchar(*stop));
1056 printf("%ld-%ld\n", (long)startst, (long)stopst);
1060 #define PCHARDONE /* never again */
1062 - pchar - make a character printable
1064 == static const char *pchar(int ch);
1067 * Is this identical to regchar() over in debug.c? Well, yes. But a
1068 * duplicate here avoids having a debugging-capable regexec.o tied to
1069 * a matching debug.o, and this is convenient. It all disappears in
1070 * the non-debug compilation anyway, so it doesn't matter much.
1072 static const char * /* -> representation */
1075 static char pbuf[10];
1077 if (isprint((uch)ch) || ch == ' ')
1078 sprintf(pbuf, "%c", ch);
1080 sprintf(pbuf, "\\%o", ch);