1044 lines
26 KiB
C
1044 lines
26 KiB
C
/*
|
|
Copyright 1992, 1993, 1994, 1997 Henry Spencer. All rights reserved.
|
|
This software is not subject to any license of the American Telephone
|
|
and Telegraph Company or of the Regents of the University of California.
|
|
|
|
Permission is granted to anyone to use this software for any purpose on
|
|
any computer system, and to alter it and redistribute it, subject
|
|
to the following restrictions:
|
|
|
|
1. The author is not responsible for the consequences of use of this
|
|
software, no matter how awful, even if they arise from flaws in it.
|
|
|
|
2. The origin of this software must not be misrepresented, either by
|
|
explicit claim or by omission. Since few users ever read sources,
|
|
credits must appear in the documentation.
|
|
|
|
3. Altered versions must be plainly marked as such, and must not be
|
|
misrepresented as being the original software. Since few users
|
|
ever read sources, credits must appear in the documentation.
|
|
|
|
4. This notice may not be removed or altered.
|
|
*/
|
|
/*
|
|
* 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);
|
|
return(NULL);
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
/*
|
|
- 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 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 != (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
|
|
|
|
/* __SRCVERSION("engine.h $Rev: 153052 $"); */
|