diff options
Diffstat (limited to 'winsup/cygwin/regex/engine.c')
-rw-r--r-- | winsup/cygwin/regex/engine.c | 1019 |
1 files changed, 0 insertions, 1019 deletions
diff --git a/winsup/cygwin/regex/engine.c b/winsup/cygwin/regex/engine.c deleted file mode 100644 index 919fe3f..0000000 --- a/winsup/cygwin/regex/engine.c +++ /dev/null @@ -1,1019 +0,0 @@ -/* - * 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 int 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 |