-/*
- * 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
-
-/* 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 */
-};
-
-#include "engine.ih"
-
-#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®_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(register 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)
-register struct re_guts *g;
-char *string;
-size_t nmatch;
-regmatch_t pmatch[];
-int eflags;
-{
- register char *endp;
- register size_t i;
- struct match mv;
- register struct match *m = &mv;
- register char *dp;
- const register sopno gf = g->firststate+1; /* +1 for OEND */
- const register sopno gl = g->laststate;
- char *start;
- char *stop;
-
- /* simplify the situation where possible */
- if (g->cflags®_NOSUB)
- nmatch = 0;
- if (eflags®_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) {
- 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);
-
- /* 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++;
- }
- 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®_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");
- start = m->coldp + 1; /* recycle starting later */
- 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(register struct match *m, char *start, \
- == char *stop, sopno startst, sopno stopst);
- */
-static char * /* == stop (success) always */
-dissect(m, start, stop, startst, stopst)
-register struct match *m;
-char *start;
-char *stop;
-sopno startst;
-sopno stopst;
-{
- register int i;
- register sopno ss; /* start sop of current subRE */
- register sopno es; /* end sop of current subRE */
- register char *sp; /* start of string matched by it */
- register char *stp; /* string matched by it cannot pass here */
- register char *rest; /* start of rest of string */
- register char *tail; /* string unmatched by rest of RE */
- register sopno ssub; /* start sop of subsubRE */
- register sopno esub; /* end sop of subsubRE */
- register char *ssp; /* start of string matched by subsubRE */
- register char *sep; /* end of string matched by subsubRE */
- register char *oldssp; /* previous ssp */
- register 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++;
- break;
- case OBOL:
- case OEOL:
- case OBOW:
- case OEOW:
- break;
- case OANY:
- case OANYOF:
- sp++;
- 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;
- }
- 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;
- 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(register 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)
-register struct match *m;
-char *start;
-char *stop;
-sopno startst;
-sopno stopst;
-sopno lev; /* PLUS nesting level */
-{
- register int i;
- register sopno ss; /* start sop of current subRE */
- register char *sp; /* start of string matched by it */
- register sopno ssub; /* start sop of subsubRE */
- register sopno esub; /* end sop of subsubRE */
- register char *ssp; /* start of string matched by subsubRE */
- register char *dp;
- register size_t len;
- register int hard;
- register sop s;
- register regoff_t offsave;
- register cset *cs;
-
- 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 || *sp++ != (char)OPND(s))
- return(NULL);
- break;
- case OANY:
- if (sp == stop)
- return(NULL);
- sp++;
- break;
- case OANYOF:
- cs = &m->g->sets[OPND(s)];
- if (sp == stop || !CHIN(cs, *sp++))
- return(NULL);
- break;
- case OBOL:
- if ( (sp == m->beginp && !(m->eflags®_NOTBOL)) ||
- (sp < m->endp && *(sp-1) == '\n' &&
- (m->g->cflags®_NEWLINE)) )
- { /* yes */ }
- else
- return(NULL);
- break;
- case OEOL:
- if ( (sp == m->endp && !(m->eflags®_NOTEOL)) ||
- (sp < m->endp && *sp == '\n' &&
- (m->g->cflags®_NEWLINE)) )
- { /* yes */ }
- else
- return(NULL);
- break;
- case OBOW:
- if (( (sp == m->beginp && !(m->eflags®_NOTBOL)) ||
- (sp < m->endp && *(sp-1) == '\n' &&
- (m->g->cflags®_NEWLINE)) ||
- (sp > m->beginp &&
- !ISWORD(*(sp-1))) ) &&
- (sp < m->endp && ISWORD(*sp)) )
- { /* yes */ }
- else
- return(NULL);
- break;
- case OEOW:
- if (( (sp == m->endp && !(m->eflags®_NOTEOL)) ||
- (sp < m->endp && *sp == '\n' &&
- (m->g->cflags®_NEWLINE)) ||
- (sp < m->endp && !ISWORD(*sp)) ) &&
- (sp > m->beginp && ISWORD(*(sp-1))) )
- { /* 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((char *)NULL); /* dummy */
-}
-
-/*
- - fast - step through the string at top speed
- == static char *fast(register 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)
-register struct match *m;
-char *start;
-char *stop;
-sopno startst;
-sopno stopst;
-{
- register states st = m->st;
- register states fresh = m->fresh;
- register states tmp = m->tmp;
- register char *p = start;
- register int c = (start == m->beginp) ? OUT : *(start-1);
- register int lastc; /* previous c */
- register int flagch;
- register int i;
- register char *coldp; /* last p after which no match was underway */
-
- CLEAR(st);
- SET1(st, startst);
- st = step(m->g, startst, stopst, st, NOTHING, st);
- ASSIGN(fresh, st);
- SP("start", st, *p);
- coldp = NULL;
- for (;;) {
- /* next character */
- lastc = c;
- c = (p == m->endp) ? OUT : *p;
- 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®_NEWLINE) ||
- (lastc == OUT && !(m->eflags®_NOTBOL)) ) {
- flagch = BOL;
- i = m->g->nbol;
- }
- if ( (c == '\n' && m->g->cflags®_NEWLINE) ||
- (c == OUT && !(m->eflags®_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))) &&
- (c != OUT && ISWORD(c)) ) {
- flagch = BOW;
- }
- if ( (lastc != OUT && ISWORD(lastc)) &&
- (flagch == EOL || (c != OUT && !ISWORD(c))) ) {
- 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++;
- }
-
- assert(coldp != NULL);
- m->coldp = coldp;
- if (ISSET(st, stopst))
- return(p+1);
- else
- return(NULL);
-}
-
-/*
- - slow - step through the string more deliberately
- == static char *slow(register struct match *m, char *start, \
- == char *stop, sopno startst, sopno stopst);
- */
-static char * /* where it ended */
-slow(m, start, stop, startst, stopst)
-register struct match *m;
-char *start;
-char *stop;
-sopno startst;
-sopno stopst;
-{
- register states st = m->st;
- register states empty = m->empty;
- register states tmp = m->tmp;
- register char *p = start;
- register int c = (start == m->beginp) ? OUT : *(start-1);
- register int lastc; /* previous c */
- register int flagch;
- register int i;
- register char *matchp; /* last p at which a match ended */
-
- 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;
- for (;;) {
- /* next character */
- lastc = c;
- c = (p == m->endp) ? OUT : *p;
-
- /* is there an EOL and/or BOL between lastc and c? */
- flagch = '\0';
- i = 0;
- if ( (lastc == '\n' && m->g->cflags®_NEWLINE) ||
- (lastc == OUT && !(m->eflags®_NOTBOL)) ) {
- flagch = BOL;
- i = m->g->nbol;
- }
- if ( (c == '\n' && m->g->cflags®_NEWLINE) ||
- (c == OUT && !(m->eflags®_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))) &&
- (c != OUT && ISWORD(c)) ) {
- flagch = BOW;
- }
- if ( (lastc != OUT && ISWORD(lastc)) &&
- (flagch == EOL || (c != OUT && !ISWORD(c))) ) {
- 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++;
- }
-
- return(matchp);
-}
-
-
-/*
- - step - map set of states reachable before char to set reachable after
- == static states step(register struct re_guts *g, sopno start, sopno stop, \
- == register states bef, int ch, register 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 CODEMAX (BOL+5) // highest code used
- == #define NONCHAR(c) ((c) > CHAR_MAX)
- == #define NNONCHAR (CODEMAX-CHAR_MAX)
- */
-static states
-step(g, start, stop, bef, ch, aft)
-register struct re_guts *g;
-sopno start; /* start state within strip */
-sopno stop; /* state after stop state within strip */
-register states bef; /* states reachable before */
-int ch; /* character or NONCHAR code */
-register states aft; /* states already known reachable after */
-{
- register cset *cs;
- register sop s;
- register sopno pc;
- register onestate here; /* note, macros know this name */
- register sopno look;
- register long 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 != (char)OPND(s));
- if (ch == (char)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))
- 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;
-{
- register struct re_guts *g = m->g;
- register int i;
- register int first = 1;
-
- if (!(m->eflags®_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®_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(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
projects / wxWidgets.git / commitdiff
