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regex/engine.c Libc-583 /dev/null
--- Libc/Libc-583/regex/engine.c
+++ /dev/null
@@ -1,1204 +0,0 @@
-/*-
- * Copyright (c) 1992, 1993, 1994 Henry Spencer.
- * Copyright (c) 1992, 1993, 1994
- *	The Regents of the University of California.  All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Henry Spencer.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *	This product includes software developed by the University of
- *	California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- *	@(#)engine.c	8.5 (Berkeley) 3/20/94
- */
-
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/lib/libc/regex/engine.c,v 1.14 2004/07/12 07:35:59 tjr Exp $");
-
-/*
- * The matching engine and friends.  This file is #included by regexec.c
- * after suitable #defines of a variety of macros used herein, so that
- * different state representations can be used without duplicating masses
- * of code.
- */
-
-#ifdef SNAMES
-#define	matcher	smatcher
-#define	fast	sfast
-#define	slow	sslow
-#define	dissect	sdissect
-#define	backref	sbackref
-#define	step	sstep
-#define	print	sprint
-#define	at	sat
-#define	match	smat
-#endif
-#ifdef LNAMES
-#define	matcher	lmatcher
-#define	fast	lfast
-#define	slow	lslow
-#define	dissect	ldissect
-#define	backref	lbackref
-#define	step	lstep
-#define	print	lprint
-#define	at	lat
-#define	match	lmat
-#endif
-#ifdef MNAMES
-#define	matcher	mmatcher
-#define	fast	mfast
-#define	slow	mslow
-#define	dissect	mdissect
-#define	backref	mbackref
-#define	step	mstep
-#define	print	mprint
-#define	at	mat
-#define	match	mmat
-#endif
-
-/* another structure passed up and down to avoid zillions of parameters */
-struct match {
-	struct re_guts *g;
-	int eflags;
-	regmatch_t *pmatch;	/* [nsub+1] (0 element unused) */
-	char *offp;		/* offsets work from here */
-	char *beginp;		/* start of string -- virtual NUL precedes */
-	char *endp;		/* end of string -- virtual NUL here */
-	char *coldp;		/* can be no match starting before here */
-	char **lastpos;		/* [nplus+1] */
-	STATEVARS;
-	states st;		/* current states */
-	states fresh;		/* states for a fresh start */
-	states tmp;		/* temporary */
-	states empty;		/* empty set of states */
-	mbstate_t mbs;		/* multibyte conversion state */
-};
-
-/* ========= begin header generated by ./mkh ========= */
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* === engine.c === */
-static int matcher(struct re_guts *g, char *string, size_t nmatch, regmatch_t pmatch[], int eflags);
-static char *dissect(struct match *m, char *start, char *stop, sopno startst, sopno stopst);
-static char *backref(struct match *m, char *start, char *stop, sopno startst, sopno stopst, sopno lev);
-static char *fast(struct match *m, char *start, char *stop, sopno startst, sopno stopst);
-static char *slow(struct match *m, char *start, char *stop, sopno startst, sopno stopst);
-static states step(struct re_guts *g, sopno start, sopno stop, states bef, wint_t ch, states aft);
-#define	BOL	(OUT-1)
-#define	EOL	(BOL-1)
-#define	BOLEOL	(BOL-2)
-#define	NOTHING	(BOL-3)
-#define	BOW	(BOL-4)
-#define	EOW	(BOL-5)
-#define	BADCHAR	(BOL-6)
-#define	NONCHAR(c)	((c) <= OUT)
-#ifdef REDEBUG
-static void print(struct match *m, char *caption, states st, int ch, FILE *d);
-#endif
-#ifdef REDEBUG
-static void at(struct match *m, char *title, char *start, char *stop, sopno startst, sopno stopst);
-#endif
-#ifdef REDEBUG
-static char *pchar(int ch);
-#endif
-
-#ifdef __cplusplus
-}
-#endif
-/* ========= end header generated by ./mkh ========= */
-
-#ifdef REDEBUG
-#define	SP(t, s, c)	print(m, t, s, c, stdout)
-#define	AT(t, p1, p2, s1, s2)	at(m, t, p1, p2, s1, s2)
-#define	NOTE(str)	{ if (m->eflags&REG_TRACE) printf("=%s\n", (str)); }
-#else
-#define	SP(t, s, c)	/* nothing */
-#define	AT(t, p1, p2, s1, s2)	/* nothing */
-#define	NOTE(s)	/* nothing */
-#endif
-
-/*
- - matcher - the actual matching engine
- == static int matcher(struct re_guts *g, char *string, \
- ==	size_t nmatch, regmatch_t pmatch[], int eflags);
- */
-static int			/* 0 success, REG_NOMATCH failure */
-matcher(g, string, nmatch, pmatch, eflags)
-struct re_guts *g;
-char *string;
-size_t nmatch;
-regmatch_t pmatch[];
-int eflags;
-{
-	char *endp;
-	int i;
-	struct match mv;
-	struct match *m = &mv;
-	char *dp;
-	const sopno gf = g->firststate+1;	/* +1 for OEND */
-	const sopno gl = g->laststate;
-	char *start;
-	char *stop;
-	/* Boyer-Moore algorithms variables */
-	char *pp;
-	int cj, mj;
-	char *mustfirst;
-	char *mustlast;
-	int *matchjump;
-	int *charjump;
-
-	/* simplify the situation where possible */
-	if (g->cflags&REG_NOSUB)
-		nmatch = 0;
-	if (eflags&REG_STARTEND) {
-		start = string + pmatch[0].rm_so;
-		stop = string + pmatch[0].rm_eo;
-	} else {
-		start = string;
-		stop = start + strlen(start);
-	}
-	if (stop < start)
-		return(REG_INVARG);
-
-	/* prescreening; this does wonders for this rather slow code */
-	if (g->must != NULL) {
-		if (g->charjump != NULL && g->matchjump != NULL) {
-			mustfirst = g->must;
-			mustlast = g->must + g->mlen - 1;
-			charjump = g->charjump;
-			matchjump = g->matchjump;
-			pp = mustlast;
-			for (dp = start+g->mlen-1; dp < stop;) {
-				/* Fast skip non-matches */
-				while (dp < stop && charjump[(int)*dp])
-					dp += charjump[(int)*dp];
-
-				if (dp >= stop)
-					break;
-
-				/* Greedy matcher */
-				/* We depend on not being used for
-				 * for strings of length 1
-				 */
-				while (*--dp == *--pp && pp != mustfirst);
-
-				if (*dp == *pp)
-					break;
-
-				/* Jump to next possible match */
-				mj = matchjump[pp - mustfirst];
-				cj = charjump[(int)*dp];
-				dp += (cj < mj ? mj : cj);
-				pp = mustlast;
-			}
-			if (pp != mustfirst)
-				return(REG_NOMATCH);
-		} else {
-			for (dp = start; dp < stop; dp++)
-				if (*dp == g->must[0] &&
-				    stop - dp >= g->mlen &&
-				    memcmp(dp, g->must, (size_t)g->mlen) == 0)
-					break;
-			if (dp == stop)		/* we didn't find g->must */
-				return(REG_NOMATCH);
-		}
-	}
-
-	/* match struct setup */
-	m->g = g;
-	m->eflags = eflags;
-	m->pmatch = NULL;
-	m->lastpos = NULL;
-	m->offp = string;
-	m->beginp = start;
-	m->endp = stop;
-	STATESETUP(m, 4);
-	SETUP(m->st);
-	SETUP(m->fresh);
-	SETUP(m->tmp);
-	SETUP(m->empty);
-	CLEAR(m->empty);
-	ZAPSTATE(&m->mbs);
-
-	/* Adjust start according to moffset, to speed things up */
-	if (g->moffset > -1)
-		start = ((dp - g->moffset) < start) ? start : dp - g->moffset;
-
-	/* this loop does only one repetition except for backrefs */
-	for (;;) {
-		endp = fast(m, start, stop, gf, gl);
-		if (endp == NULL) {		/* a miss */
-			STATETEARDOWN(m);
-			return(REG_NOMATCH);
-		}
-		if (nmatch == 0 && !g->backrefs)
-			break;		/* no further info needed */
-
-		/* where? */
-		assert(m->coldp != NULL);
-		for (;;) {
-			NOTE("finding start");
-			endp = slow(m, m->coldp, stop, gf, gl);
-			if (endp != NULL)
-				break;
-			assert(m->coldp < m->endp);
-			m->coldp += XMBRTOWC(NULL, m->coldp,
-			    m->endp - m->coldp, &m->mbs, 0, g->loc);
-		}
-		if (nmatch == 1 && !g->backrefs)
-			break;		/* no further info needed */
-
-		/* oh my, he wants the subexpressions... */
-		if (m->pmatch == NULL)
-			m->pmatch = (regmatch_t *)malloc((m->g->nsub + 1) *
-							sizeof(regmatch_t));
-		if (m->pmatch == NULL) {
-			STATETEARDOWN(m);
-			return(REG_ESPACE);
-		}
-		for (i = 1; i <= m->g->nsub; i++)
-			m->pmatch[i].rm_so = m->pmatch[i].rm_eo = -1;
-		if (!g->backrefs && !(m->eflags&REG_BACKR)) {
-			NOTE("dissecting");
-			dp = dissect(m, m->coldp, endp, gf, gl);
-		} else {
-			if (g->nplus > 0 && m->lastpos == NULL)
-				m->lastpos = (char **)malloc((g->nplus+1) *
-							sizeof(char *));
-			if (g->nplus > 0 && m->lastpos == NULL) {
-				free(m->pmatch);
-				STATETEARDOWN(m);
-				return(REG_ESPACE);
-			}
-			NOTE("backref dissect");
-			dp = backref(m, m->coldp, endp, gf, gl, (sopno)0);
-		}
-		if (dp != NULL)
-			break;
-
-		/* uh-oh... we couldn't find a subexpression-level match */
-		assert(g->backrefs);	/* must be back references doing it */
-		assert(g->nplus == 0 || m->lastpos != NULL);
-		for (;;) {
-			if (dp != NULL || endp <= m->coldp)
-				break;		/* defeat */
-			NOTE("backoff");
-			endp = slow(m, m->coldp, endp-1, gf, gl);
-			if (endp == NULL)
-				break;		/* defeat */
-			/* try it on a shorter possibility */
-#ifndef NDEBUG
-			for (i = 1; i <= m->g->nsub; i++) {
-				assert(m->pmatch[i].rm_so == -1);
-				assert(m->pmatch[i].rm_eo == -1);
-			}
-#endif
-			NOTE("backoff dissect");
-			dp = backref(m, m->coldp, endp, gf, gl, (sopno)0);
-		}
-		assert(dp == NULL || dp == endp);
-		if (dp != NULL)		/* found a shorter one */
-			break;
-
-		/* despite initial appearances, there is no match here */
-		NOTE("false alarm");
-		/* recycle starting later */
-		start = m->coldp + XMBRTOWC(NULL, m->coldp,
-		    m->endp - m->coldp, &m->mbs, 0, g->loc);
-		assert(start <= stop);
-	}
-
-	/* fill in the details if requested */
-	if (nmatch > 0) {
-		pmatch[0].rm_so = m->coldp - m->offp;
-		pmatch[0].rm_eo = endp - m->offp;
-	}
-	if (nmatch > 1) {
-		assert(m->pmatch != NULL);
-		for (i = 1; i < nmatch; i++)
-			if (i <= m->g->nsub)
-				pmatch[i] = m->pmatch[i];
-			else {
-				pmatch[i].rm_so = -1;
-				pmatch[i].rm_eo = -1;
-			}
-	}
-
-	if (m->pmatch != NULL)
-		free((char *)m->pmatch);
-	if (m->lastpos != NULL)
-		free((char *)m->lastpos);
-	STATETEARDOWN(m);
-	return(0);
-}
-
-/*
- - dissect - figure out what matched what, no back references
- == static char *dissect(struct match *m, char *start, \
- ==	char *stop, sopno startst, sopno stopst);
- */
-static char *			/* == stop (success) always */
-dissect(m, start, stop, startst, stopst)
-struct match *m;
-char *start;
-char *stop;
-sopno startst;
-sopno stopst;
-{
-	int i;
-	sopno ss;		/* start sop of current subRE */
-	sopno es;		/* end sop of current subRE */
-	char *sp;		/* start of string matched by it */
-	char *stp;		/* string matched by it cannot pass here */
-	char *rest;		/* start of rest of string */
-	char *tail;		/* string unmatched by rest of RE */
-	sopno ssub;		/* start sop of subsubRE */
-	sopno esub;		/* end sop of subsubRE */
-	char *ssp;		/* start of string matched by subsubRE */
-	char *sep;		/* end of string matched by subsubRE */
-	char *oldssp;		/* previous ssp */
-	char *dp;
-
-	AT("diss", start, stop, startst, stopst);
-	sp = start;
-	for (ss = startst; ss < stopst; ss = es) {
-		/* identify end of subRE */
-		es = ss;
-		switch (OP(m->g->strip[es])) {
-		case OPLUS_:
-		case OQUEST_:
-			es += OPND(m->g->strip[es]);
-			break;
-		case OCH_:
-			while (OP(m->g->strip[es]) != O_CH)
-				es += OPND(m->g->strip[es]);
-			break;
-		}
-		es++;
-
-		/* figure out what it matched */
-		switch (OP(m->g->strip[ss])) {
-		case OEND:
-			assert(nope);
-			break;
-		case OCHAR:
-			sp += XMBRTOWC(NULL, sp, stop - start, &m->mbs, 0, m->g->loc);
-			break;
-		case OBOL:
-		case OEOL:
-		case OBOW:
-		case OEOW:
-			break;
-		case OANY:
-		case OANYOF:
-			sp += XMBRTOWC(NULL, sp, stop - start, &m->mbs, 0, m->g->loc);
-			break;
-		case OBACK_:
-		case O_BACK:
-			assert(nope);
-			break;
-		/* cases where length of match is hard to find */
-		case OQUEST_:
-			stp = stop;
-			for (;;) {
-				/* how long could this one be? */
-				rest = slow(m, sp, stp, ss, es);
-				assert(rest != NULL);	/* it did match */
-				/* could the rest match the rest? */
-				tail = slow(m, rest, stop, es, stopst);
-				if (tail == stop)
-					break;		/* yes! */
-				/* no -- try a shorter match for this one */
-				stp = rest - 1;
-				assert(stp >= sp);	/* it did work */
-			}
-			ssub = ss + 1;
-			esub = es - 1;
-			/* did innards match? */
-			if (slow(m, sp, rest, ssub, esub) != NULL) {
-				dp = dissect(m, sp, rest, ssub, esub);
-				assert(dp == rest);
-			} else		/* no */
-				assert(sp == rest);
-			sp = rest;
-			break;
-		case OPLUS_:
-			stp = stop;
-			for (;;) {
-				/* how long could this one be? */
-				rest = slow(m, sp, stp, ss, es);
-				assert(rest != NULL);	/* it did match */
-				/* could the rest match the rest? */
-				tail = slow(m, rest, stop, es, stopst);
-				if (tail == stop)
-					break;		/* yes! */
-				/* no -- try a shorter match for this one */
-				stp = rest - 1;
-				assert(stp >= sp);	/* it did work */
-			}
-			ssub = ss + 1;
-			esub = es - 1;
-			ssp = sp;
-			oldssp = ssp;
-			for (;;) {	/* find last match of innards */
-				sep = slow(m, ssp, rest, ssub, esub);
-				if (sep == NULL || sep == ssp)
-					break;	/* failed or matched null */
-				oldssp = ssp;	/* on to next try */
-				ssp = sep;
-			}
-			if (sep == NULL) {
-				/* last successful match */
-				sep = ssp;
-				ssp = oldssp;
-			}
-			else if (tail==rest) {
-				/* Fix for test expr 105 */
-				ssp = oldssp;
-			}
-			assert(sep == rest);	/* must exhaust substring */
-			assert(slow(m, ssp, sep, ssub, esub) == rest);
-			dp = dissect(m, ssp, sep, ssub, esub);
-			assert(dp == sep);
-			sp = rest;
-			break;
-		case OCH_:
-			stp = stop;
-			for (;;) {
-				/* how long could this one be? */
-				rest = slow(m, sp, stp, ss, es);
-				assert(rest != NULL);	/* it did match */
-				/* could the rest match the rest? */
-				tail = slow(m, rest, stop, es, stopst);
-				if (tail == stop)
-					break;		/* yes! */
-				/* no -- try a shorter match for this one */
-				stp = rest - 1;
-				assert(stp >= sp);	/* it did work */
-			}
-			ssub = ss + 1;
-			esub = ss + OPND(m->g->strip[ss]) - 1;
-			assert(OP(m->g->strip[esub]) == OOR1);
-			for (;;) {	/* find first matching branch */
-				if (slow(m, sp, rest, ssub, esub) == rest)
-					break;	/* it matched all of it */
-				/* that one missed, try next one */
-				assert(OP(m->g->strip[esub]) == OOR1);
-				esub++;
-				assert(OP(m->g->strip[esub]) == OOR2);
-				ssub = esub + 1;
-				esub += OPND(m->g->strip[esub]);
-				if (OP(m->g->strip[esub]) == OOR2)
-					esub--;
-				else
-					assert(OP(m->g->strip[esub]) == O_CH);
-			}
-			dp = dissect(m, sp, rest, ssub, esub);
-			assert(dp == rest);
-			sp = rest;
-			break;
-		case O_PLUS:
-		case O_QUEST:
-		case OOR1:
-		case OOR2:
-		case O_CH:
-			assert(nope);
-			break;
-		case OLPAREN:
-			i = OPND(m->g->strip[ss]);
-			assert(0 < i && i <= m->g->nsub);
-			m->pmatch[i].rm_so = sp - m->offp;
-			/* fix for T.regcomp 43: don't remember previous
-			   subexpression matches beyond the current one (i) */
-			i++;
-			while (i<= m->g->nsub) {
-				m->pmatch[i].rm_so = -1;
-				m->pmatch[i].rm_eo = -1;
-				i++;
-			}
-			break;
-		case ORPAREN:
-			i = OPND(m->g->strip[ss]);
-			assert(0 < i && i <= m->g->nsub);
-			m->pmatch[i].rm_eo = sp - m->offp;
-			break;
-		default:		/* uh oh */
-			assert(nope);
-			break;
-		}
-	}
-
-	assert(sp == stop);
-	return(sp);
-}
-
-/*
- - backref - figure out what matched what, figuring in back references
- == static char *backref(struct match *m, char *start, \
- ==	char *stop, sopno startst, sopno stopst, sopno lev);
- */
-static char *			/* == stop (success) or NULL (failure) */
-backref(m, start, stop, startst, stopst, lev)
-struct match *m;
-char *start;
-char *stop;
-sopno startst;
-sopno stopst;
-sopno lev;			/* PLUS nesting level */
-{
-	int i;
-	sopno ss;		/* start sop of current subRE */
-	char *sp;		/* start of string matched by it */
-	sopno ssub;		/* start sop of subsubRE */
-	sopno esub;		/* end sop of subsubRE */
-	char *ssp;		/* start of string matched by subsubRE */
-	char *dp;
-	size_t len;
-	int hard;
-	sop s;
-	regoff_t offsave;
-	cset *cs;
-	wint_t wc;
-
-	AT("back", start, stop, startst, stopst);
-	sp = start;
-
-	/* get as far as we can with easy stuff */
-	hard = 0;
-	for (ss = startst; !hard && ss < stopst; ss++)
-		switch (OP(s = m->g->strip[ss])) {
-		case OCHAR:
-			if (sp == stop)
-				return(NULL);
-			sp += XMBRTOWC(&wc, sp, stop - sp, &m->mbs, BADCHAR, m->g->loc);
-			if (wc != OPND(s))
-				return(NULL);
-			break;
-		case OANY:
-			if (sp == stop)
-				return(NULL);
-			sp += XMBRTOWC(&wc, sp, stop - sp, &m->mbs, BADCHAR, m->g->loc);
-			if (wc == BADCHAR)
-				return (NULL);
-			break;
-		case OANYOF:
-			if (sp == stop)
-				return (NULL);
-			cs = &m->g->sets[OPND(s)];
-			sp += XMBRTOWC(&wc, sp, stop - sp, &m->mbs, BADCHAR, m->g->loc);
-			if (wc == BADCHAR || !CHIN(cs, wc, m->g->loc))
-				return(NULL);
-			break;
-		case OBOL:
-			if ( (sp == m->beginp && !(m->eflags&REG_NOTBOL)) ||
-					(sp < m->endp && *(sp-1) == '\n' &&
-						(m->g->cflags&REG_NEWLINE)) )
-				{ /* yes */ }
-			else
-				return(NULL);
-			break;
-		case OEOL:
-			if ( (sp == m->endp && !(m->eflags&REG_NOTEOL)) ||
-					(sp < m->endp && *sp == '\n' &&
-						(m->g->cflags&REG_NEWLINE)) )
-				{ /* yes */ }
-			else
-				return(NULL);
-			break;
-		case OBOW:
-			if (( (sp == m->beginp && !(m->eflags&REG_NOTBOL)) ||
-					(sp < m->endp && *(sp-1) == '\n' &&
-						(m->g->cflags&REG_NEWLINE)) ||
-					(sp > m->beginp &&
-							!ISWORD(*(sp-1), m->g->loc)) ) &&
-					(sp < m->endp && ISWORD(*sp, m->g->loc)) )
-				{ /* yes */ }
-			else
-				return(NULL);
-			break;
-		case OEOW:
-			if (( (sp == m->endp && !(m->eflags&REG_NOTEOL)) ||
-					(sp < m->endp && *sp == '\n' &&
-						(m->g->cflags&REG_NEWLINE)) ||
-					(sp < m->endp && !ISWORD(*sp, m->g->loc)) ) &&
-					(sp > m->beginp && ISWORD(*(sp-1), m->g->loc)) )
-				{ /* yes */ }
-			else
-				return(NULL);
-			break;
-		case O_QUEST:
-			break;
-		case OOR1:	/* matches null but needs to skip */
-			ss++;
-			s = m->g->strip[ss];
-			do {
-				assert(OP(s) == OOR2);
-				ss += OPND(s);
-			} while (OP(s = m->g->strip[ss]) != O_CH);
-			/* note that the ss++ gets us past the O_CH */
-			break;
-		default:	/* have to make a choice */
-			hard = 1;
-			break;
-		}
-	if (!hard) {		/* that was it! */
-		if (sp != stop)
-			return(NULL);
-		return(sp);
-	}
-	ss--;			/* adjust for the for's final increment */
-
-	/* the hard stuff */
-	AT("hard", sp, stop, ss, stopst);
-	s = m->g->strip[ss];
-	switch (OP(s)) {
-	case OBACK_:		/* the vilest depths */
-		i = OPND(s);
-		assert(0 < i && i <= m->g->nsub);
-		if (m->pmatch[i].rm_eo == -1)
-			return(NULL);
-		assert(m->pmatch[i].rm_so != -1);
-		len = m->pmatch[i].rm_eo - m->pmatch[i].rm_so;
-		assert(stop - m->beginp >= len);
-		if (sp > stop - len)
-			return(NULL);	/* not enough left to match */
-		ssp = m->offp + m->pmatch[i].rm_so;
-		if (memcmp(sp, ssp, len) != 0)
-			return(NULL);
-		while (m->g->strip[ss] != SOP(O_BACK, i))
-			ss++;
-		return(backref(m, sp+len, stop, ss+1, stopst, lev));
-		break;
-	case OQUEST_:		/* to null or not */
-		dp = backref(m, sp, stop, ss+1, stopst, lev);
-		if (dp != NULL)
-			return(dp);	/* not */
-		return(backref(m, sp, stop, ss+OPND(s)+1, stopst, lev));
-		break;
-	case OPLUS_:
-		assert(m->lastpos != NULL);
-		assert(lev+1 <= m->g->nplus);
-		m->lastpos[lev+1] = sp;
-		return(backref(m, sp, stop, ss+1, stopst, lev+1));
-		break;
-	case O_PLUS:
-		if (sp == m->lastpos[lev])	/* last pass matched null */
-			return(backref(m, sp, stop, ss+1, stopst, lev-1));
-		/* try another pass */
-		m->lastpos[lev] = sp;
-		dp = backref(m, sp, stop, ss-OPND(s)+1, stopst, lev);
-		if (dp == NULL)
-			return(backref(m, sp, stop, ss+1, stopst, lev-1));
-		else
-			return(dp);
-		break;
-	case OCH_:		/* find the right one, if any */
-		ssub = ss + 1;
-		esub = ss + OPND(s) - 1;
-		assert(OP(m->g->strip[esub]) == OOR1);
-		for (;;) {	/* find first matching branch */
-			dp = backref(m, sp, stop, ssub, esub, lev);
-			if (dp != NULL)
-				return(dp);
-			/* that one missed, try next one */
-			if (OP(m->g->strip[esub]) == O_CH)
-				return(NULL);	/* there is none */
-			esub++;
-			assert(OP(m->g->strip[esub]) == OOR2);
-			ssub = esub + 1;
-			esub += OPND(m->g->strip[esub]);
-			if (OP(m->g->strip[esub]) == OOR2)
-				esub--;
-			else
-				assert(OP(m->g->strip[esub]) == O_CH);
-		}
-		break;
-	case OLPAREN:		/* must undo assignment if rest fails */
-		i = OPND(s);
-		assert(0 < i && i <= m->g->nsub);
-		offsave = m->pmatch[i].rm_so;
-		m->pmatch[i].rm_so = sp - m->offp;
-		dp = backref(m, sp, stop, ss+1, stopst, lev);
-		if (dp != NULL)
-			return(dp);
-		m->pmatch[i].rm_so = offsave;
-		return(NULL);
-		break;
-	case ORPAREN:		/* must undo assignment if rest fails */
-		i = OPND(s);
-		assert(0 < i && i <= m->g->nsub);
-		offsave = m->pmatch[i].rm_eo;
-		m->pmatch[i].rm_eo = sp - m->offp;
-		dp = backref(m, sp, stop, ss+1, stopst, lev);
-		if (dp != NULL)
-			return(dp);
-		m->pmatch[i].rm_eo = offsave;
-		return(NULL);
-		break;
-	default:		/* uh oh */
-		assert(nope);
-		break;
-	}
-
-	/* "can't happen" */
-	assert(nope);
-	/* NOTREACHED */
-	return "shut up gcc";
-}
-
-/*
- - fast - step through the string at top speed
- == static char *fast(struct match *m, char *start, \
- ==	char *stop, sopno startst, sopno stopst);
- */
-static char *			/* where tentative match ended, or NULL */
-fast(m, start, stop, startst, stopst)
-struct match *m;
-char *start;
-char *stop;
-sopno startst;
-sopno stopst;
-{
-	states st = m->st;
-	states fresh = m->fresh;
-	states tmp = m->tmp;
-	char *p = start;
-	wint_t c;
-	wint_t lastc;		/* previous c */
-	wint_t flagch;
-	int i;
-	char *coldp;		/* last p after which no match was underway */
-	size_t clen;
-
-	CLEAR(st);
-	SET1(st, startst);
-	st = step(m->g, startst, stopst, st, NOTHING, st);
-	ASSIGN(fresh, st);
-	SP("start", st, *p);
-	coldp = NULL;
-	if (start == m->beginp)
-		c = OUT;
-	else {
-		/*
-		 * XXX Wrong if the previous character was multi-byte.
-		 * Newline never is (in encodings supported by FreeBSD),
-		 * so this only breaks the ISWORD tests below.
-		 */
-		c = (uch)*(start - 1);
-	}
-	for (;;) {
-		/* next character */
-		lastc = c;
-		if (p == m->endp)
-			c = OUT;
-		else
-			clen = XMBRTOWC(&c, p, m->endp - p, &m->mbs, BADCHAR, m->g->loc);
-		if (EQ(st, fresh))
-			coldp = p;
-
-		/* is there an EOL and/or BOL between lastc and c? */
-		flagch = '\0';
-		i = 0;
-		if ( (lastc == '\n' && m->g->cflags&REG_NEWLINE) ||
-				(lastc == OUT && !(m->eflags&REG_NOTBOL)) ) {
-			flagch = BOL;
-			i = m->g->nbol;
-		}
-		if ( (c == '\n' && m->g->cflags&REG_NEWLINE) ||
-				(c == OUT && !(m->eflags&REG_NOTEOL)) ) {
-			flagch = (flagch == BOL) ? BOLEOL : EOL;
-			i += m->g->neol;
-		}
-		if (i != 0) {
-			for (; i > 0; i--)
-				st = step(m->g, startst, stopst, st, flagch, st);
-			SP("boleol", st, c);
-		}
-
-		/* how about a word boundary? */
-		if ( (flagch == BOL || (lastc != OUT && !ISWORD(lastc, m->g->loc))) &&
-					(c != OUT && ISWORD(c, m->g->loc)) ) {
-			flagch = BOW;
-		}
-		if ( (lastc != OUT && ISWORD(lastc, m->g->loc)) &&
-				(flagch == EOL || (c != OUT && !ISWORD(c, m->g->loc))) ) {
-			flagch = EOW;
-		}
-		if (flagch == BOW || flagch == EOW) {
-			st = step(m->g, startst, stopst, st, flagch, st);
-			SP("boweow", st, c);
-		}
-
-		/* are we done? */
-		if (ISSET(st, stopst) || p == stop)
-			break;		/* NOTE BREAK OUT */
-
-		/* no, we must deal with this character */
-		ASSIGN(tmp, st);
-		ASSIGN(st, fresh);
-		assert(c != OUT);
-		st = step(m->g, startst, stopst, tmp, c, st);
-		SP("aft", st, c);
-		assert(EQ(step(m->g, startst, stopst, st, NOTHING, st), st));
-		p += clen;
-	}
-
-	assert(coldp != NULL);
-	m->coldp = coldp;
-	if (ISSET(st, stopst))
-		return(p+XMBRTOWC(NULL, p, m->endp - p, &m->mbs, 0, m->g->loc));
-	else
-		return(NULL);
-}
-
-/*
- - slow - step through the string more deliberately
- == static char *slow(struct match *m, char *start, \
- ==	char *stop, sopno startst, sopno stopst);
- */
-static char *			/* where it ended */
-slow(m, start, stop, startst, stopst)
-struct match *m;
-char *start;
-char *stop;
-sopno startst;
-sopno stopst;
-{
-	states st = m->st;
-	states empty = m->empty;
-	states tmp = m->tmp;
-	char *p = start;
-	wint_t c;
-	wint_t lastc;		/* previous c */
-	wint_t flagch;
-	int i;
-	char *matchp;		/* last p at which a match ended */
-	size_t clen;
-
-	AT("slow", start, stop, startst, stopst);
-	CLEAR(st);
-	SET1(st, startst);
-	SP("sstart", st, *p);
-	st = step(m->g, startst, stopst, st, NOTHING, st);
-	matchp = NULL;
-	if (start == m->beginp)
-		c = OUT;
-	else {
-		/*
-		 * XXX Wrong if the previous character was multi-byte.
-		 * Newline never is (in encodings supported by FreeBSD),
-		 * so this only breaks the ISWORD tests below.
-		 */
-		c = (uch)*(start - 1);
-	}
-	for (;;) {
-		/* next character */
-		lastc = c;
-		if (p == m->endp) {
-			c = OUT;
-			clen = 0;
-		} else
-			clen = XMBRTOWC(&c, p, m->endp - p, &m->mbs, BADCHAR, m->g->loc);
-
-		/* is there an EOL and/or BOL between lastc and c? */
-		flagch = '\0';
-		i = 0;
-		if ( (lastc == '\n' && m->g->cflags&REG_NEWLINE) ||
-				(lastc == OUT && !(m->eflags&REG_NOTBOL)) ) {
-			flagch = BOL;
-			i = m->g->nbol;
-		}
-		if ( (c == '\n' && m->g->cflags&REG_NEWLINE) ||
-				(c == OUT && !(m->eflags&REG_NOTEOL)) ) {
-			flagch = (flagch == BOL) ? BOLEOL : EOL;
-			i += m->g->neol;
-		}
-		if (i != 0) {
-			for (; i > 0; i--)
-				st = step(m->g, startst, stopst, st, flagch, st);
-			SP("sboleol", st, c);
-		}
-
-		/* how about a word boundary? */
-		if ( (flagch == BOL || (lastc != OUT && !ISWORD(lastc, m->g->loc))) &&
-					(c != OUT && ISWORD(c, m->g->loc)) ) {
-			flagch = BOW;
-		}
-		if ( (lastc != OUT && ISWORD(lastc, m->g->loc)) &&
-				(flagch == EOL || (c != OUT && !ISWORD(c, m->g->loc))) ) {
-			flagch = EOW;
-		}
-		if (flagch == BOW || flagch == EOW) {
-			st = step(m->g, startst, stopst, st, flagch, st);
-			SP("sboweow", st, c);
-		}
-
-		/* are we done? */
-		if (ISSET(st, stopst))
-			matchp = p;
-		if (EQ(st, empty) || p == stop)
-			break;		/* NOTE BREAK OUT */
-
-		/* no, we must deal with this character */
-		ASSIGN(tmp, st);
-		ASSIGN(st, empty);
-		assert(c != OUT);
-		st = step(m->g, startst, stopst, tmp, c, st);
-		SP("saft", st, c);
-		assert(EQ(step(m->g, startst, stopst, st, NOTHING, st), st));
-		p += clen;
-	}
-
-	return(matchp);
-}
-
-
-/*
- - step - map set of states reachable before char to set reachable after
- == static states step(struct re_guts *g, sopno start, sopno stop, \
- ==	states bef, int ch, states aft);
- == #define	BOL	(OUT-1)
- == #define	EOL	(BOL-1)
- == #define	BOLEOL	(BOL-2)
- == #define	NOTHING	(BOL-3)
- == #define	BOW	(BOL-4)
- == #define	EOW	(BOL-5)
- == #define	BADCHAR	(BOL-6)
- == #define	NONCHAR(c)	((c) <= OUT)
- */
-static states
-step(g, start, stop, bef, ch, aft)
-struct re_guts *g;
-sopno start;			/* start state within strip */
-sopno stop;			/* state after stop state within strip */
-states bef;			/* states reachable before */
-wint_t ch;			/* character or NONCHAR code */
-states aft;			/* states already known reachable after */
-{
-	cset *cs;
-	sop s;
-	sopno pc;
-	onestate here;		/* note, macros know this name */
-	sopno look;
-	int i;
-
-	for (pc = start, INIT(here, pc); pc != stop; pc++, INC(here)) {
-		s = g->strip[pc];
-		switch (OP(s)) {
-		case OEND:
-			assert(pc == stop-1);
-			break;
-		case OCHAR:
-			/* only characters can match */
-			assert(!NONCHAR(ch) || ch != OPND(s));
-			if (ch == OPND(s))
-				FWD(aft, bef, 1);
-			break;
-		case OBOL:
-			if (ch == BOL || ch == BOLEOL)
-				FWD(aft, bef, 1);
-			break;
-		case OEOL:
-			if (ch == EOL || ch == BOLEOL)
-				FWD(aft, bef, 1);
-			break;
-		case OBOW:
-			if (ch == BOW)
-				FWD(aft, bef, 1);
-			break;
-		case OEOW:
-			if (ch == EOW)
-				FWD(aft, bef, 1);
-			break;
-		case OANY:
-			if (!NONCHAR(ch))
-				FWD(aft, bef, 1);
-			break;
-		case OANYOF:
-			cs = &g->sets[OPND(s)];
-			if (!NONCHAR(ch) && CHIN(cs, ch, g->loc))
-				FWD(aft, bef, 1);
-			break;
-		case OBACK_:		/* ignored here */
-		case O_BACK:
-			FWD(aft, aft, 1);
-			break;
-		case OPLUS_:		/* forward, this is just an empty */
-			FWD(aft, aft, 1);
-			break;
-		case O_PLUS:		/* both forward and back */
-			FWD(aft, aft, 1);
-			i = ISSETBACK(aft, OPND(s));
-			BACK(aft, aft, OPND(s));
-			if (!i && ISSETBACK(aft, OPND(s))) {
-				/* oho, must reconsider loop body */
-				pc -= OPND(s) + 1;
-				INIT(here, pc);
-			}
-			break;
-		case OQUEST_:		/* two branches, both forward */
-			FWD(aft, aft, 1);
-			FWD(aft, aft, OPND(s));
-			break;
-		case O_QUEST:		/* just an empty */
-			FWD(aft, aft, 1);
-			break;
-		case OLPAREN:		/* not significant here */
-		case ORPAREN:
-			FWD(aft, aft, 1);
-			break;
-		case OCH_:		/* mark the first two branches */
-			FWD(aft, aft, 1);
-			assert(OP(g->strip[pc+OPND(s)]) == OOR2);
-			FWD(aft, aft, OPND(s));
-			break;
-		case OOR1:		/* done a branch, find the O_CH */
-			if (ISSTATEIN(aft, here)) {
-				for (look = 1;
-						OP(s = g->strip[pc+look]) != O_CH;
-						look += OPND(s))
-					assert(OP(s) == OOR2);
-				FWD(aft, aft, look);
-			}
-			break;
-		case OOR2:		/* propagate OCH_'s marking */
-			FWD(aft, aft, 1);
-			if (OP(g->strip[pc+OPND(s)]) != O_CH) {
-				assert(OP(g->strip[pc+OPND(s)]) == OOR2);
-				FWD(aft, aft, OPND(s));
-			}
-			break;
-		case O_CH:		/* just empty */
-			FWD(aft, aft, 1);
-			break;
-		default:		/* ooooops... */
-			assert(nope);
-			break;
-		}
-	}
-
-	return(aft);
-}
-
-#ifdef REDEBUG
-/*
- - print - print a set of states
- == #ifdef REDEBUG
- == static void print(struct match *m, char *caption, states st, \
- ==	int ch, FILE *d);
- == #endif
- */
-static void
-print(m, caption, st, ch, d)
-struct match *m;
-char *caption;
-states st;
-int ch;
-FILE *d;
-{
-	struct re_guts *g = m->g;
-	int i;
-	int first = 1;
-
-	if (!(m->eflags&REG_TRACE))
-		return;
-
-	fprintf(d, "%s", caption);
-	if (ch != '\0')
-		fprintf(d, " %s", pchar(ch));
-	for (i = 0; i < g->nstates; i++)
-		if (ISSET(st, i)) {
-			fprintf(d, "%s%d", (first) ? "\t" : ", ", i);
-			first = 0;
-		}
-	fprintf(d, "\n");
-}
-
-/*
- - at - print current situation
- == #ifdef REDEBUG
- == static void at(struct match *m, char *title, char *start, char *stop, \
- ==						sopno startst, sopno stopst);
- == #endif
- */
-static void
-at(m, title, start, stop, startst, stopst)
-struct match *m;
-char *title;
-char *start;
-char *stop;
-sopno startst;
-sopno stopst;
-{
-	if (!(m->eflags&REG_TRACE))
-		return;
-
-	printf("%s %s-", title, pchar(*start));
-	printf("%s ", pchar(*stop));
-	printf("%ld-%ld\n", (long)startst, (long)stopst);
-}
-
-#ifndef PCHARDONE
-#define	PCHARDONE	/* never again */
-/*
- - pchar - make a character printable
- == #ifdef REDEBUG
- == static char *pchar(int ch);
- == #endif
- *
- * Is this identical to regchar() over in debug.c?  Well, yes.  But a
- * duplicate here avoids having a debugging-capable regexec.o tied to
- * a matching debug.o, and this is convenient.  It all disappears in
- * the non-debug compilation anyway, so it doesn't matter much.
- */
-static char *			/* -> representation */
-pchar(ch)
-int ch;
-{
-	static char pbuf[10];
-
-	if (isprint((uch)ch) || ch == ' ')
-		sprintf(pbuf, "%c", ch);
-	else
-		sprintf(pbuf, "\\%o", ch);
-	return(pbuf);
-}
-#endif
-#endif
-
-#undef	matcher
-#undef	fast
-#undef	slow
-#undef	dissect
-#undef	backref
-#undef	step
-#undef	print
-#undef	at
-#undef	match