0,0 → 1,1019 |
/* Copyright (C) 1995 DJ Delorie, see COPYING.DJ for details */ |
/* |
* 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 */ |
} |
|
/* |
- 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 |
Property changes: |
Added: svn:executable |
+* |
\ No newline at end of property |