92026fed21
in llvm/ and/or llvm/contrib/clang/ respectively. Approved by: ed (mentor) Approved by: core
1035 lines
26 KiB
C++
1035 lines
26 KiB
C++
/*-
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* This code is derived from OpenBSD's libc/regex, original license follows:
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*
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* Copyright (c) 1992, 1993, 1994 Henry Spencer.
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* Copyright (c) 1992, 1993, 1994
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* The Regents of the University of California. All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* Henry Spencer.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)engine.c 8.5 (Berkeley) 3/20/94
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*/
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/*
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* The matching engine and friends. This file is #included by regexec.c
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* after suitable #defines of a variety of macros used herein, so that
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* different state representations can be used without duplicating masses
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* of code.
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*/
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#ifdef SNAMES
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#define matcher smatcher
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#define fast sfast
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#define slow sslow
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#define dissect sdissect
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#define backref sbackref
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#define step sstep
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#define print sprint
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#define at sat
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#define match smat
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#define nope snope
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#endif
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#ifdef LNAMES
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#define matcher lmatcher
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#define fast lfast
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#define slow lslow
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#define dissect ldissect
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#define backref lbackref
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#define step lstep
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#define print lprint
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#define at lat
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#define match lmat
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#define nope lnope
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#endif
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/* another structure passed up and down to avoid zillions of parameters */
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struct match {
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struct re_guts *g;
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int eflags;
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llvm_regmatch_t *pmatch; /* [nsub+1] (0 element unused) */
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const char *offp; /* offsets work from here */
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const char *beginp; /* start of string -- virtual NUL precedes */
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const char *endp; /* end of string -- virtual NUL here */
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const char *coldp; /* can be no match starting before here */
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const char **lastpos; /* [nplus+1] */
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STATEVARS;
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states st; /* current states */
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states fresh; /* states for a fresh start */
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states tmp; /* temporary */
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states empty; /* empty set of states */
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};
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static int matcher(struct re_guts *, const char *, size_t,
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llvm_regmatch_t[], int);
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static const char *dissect(struct match *, const char *, const char *, sopno,
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sopno);
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static const char *backref(struct match *, const char *, const char *, sopno,
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sopno, sopno, int);
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static const char *fast(struct match *, const char *, const char *, sopno, sopno);
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static const char *slow(struct match *, const char *, const char *, sopno, sopno);
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static states step(struct re_guts *, sopno, sopno, states, int, states);
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#define MAX_RECURSION 100
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#define BOL (OUT+1)
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#define EOL (BOL+1)
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#define BOLEOL (BOL+2)
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#define NOTHING (BOL+3)
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#define BOW (BOL+4)
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#define EOW (BOL+5)
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#define CODEMAX (BOL+5) /* highest code used */
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#define NONCHAR(c) ((c) > CHAR_MAX)
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#define NNONCHAR (CODEMAX-CHAR_MAX)
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#ifdef REDEBUG
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static void print(struct match *, char *, states, int, FILE *);
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#endif
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#ifdef REDEBUG
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static void at(struct match *, char *, char *, char *, sopno, sopno);
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#endif
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#ifdef REDEBUG
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static char *pchar(int);
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#endif
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#ifdef REDEBUG
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#define SP(t, s, c) print(m, t, s, c, stdout)
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#define AT(t, p1, p2, s1, s2) at(m, t, p1, p2, s1, s2)
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#define NOTE(str) { if (m->eflags®_TRACE) (void)printf("=%s\n", (str)); }
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static int nope = 0;
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#else
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#define SP(t, s, c) /* nothing */
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#define AT(t, p1, p2, s1, s2) /* nothing */
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#define NOTE(s) /* nothing */
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#endif
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/*
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- matcher - the actual matching engine
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*/
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static int /* 0 success, REG_NOMATCH failure */
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matcher(struct re_guts *g, const char *string, size_t nmatch,
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llvm_regmatch_t pmatch[],
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int eflags)
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{
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const char *endp;
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size_t i;
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struct match mv;
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struct match *m = &mv;
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const char *dp;
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const sopno gf = g->firststate+1; /* +1 for OEND */
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const sopno gl = g->laststate;
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const char *start;
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const char *stop;
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/* simplify the situation where possible */
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if (g->cflags®_NOSUB)
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nmatch = 0;
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if (eflags®_STARTEND) {
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start = string + pmatch[0].rm_so;
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stop = string + pmatch[0].rm_eo;
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} else {
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start = string;
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stop = start + strlen(start);
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}
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if (stop < start)
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return(REG_INVARG);
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/* prescreening; this does wonders for this rather slow code */
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if (g->must != NULL) {
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for (dp = start; dp < stop; dp++)
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if (*dp == g->must[0] && stop - dp >= g->mlen &&
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memcmp(dp, g->must, (size_t)g->mlen) == 0)
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break;
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if (dp == stop) /* we didn't find g->must */
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return(REG_NOMATCH);
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}
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/* match struct setup */
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m->g = g;
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m->eflags = eflags;
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m->pmatch = NULL;
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m->lastpos = NULL;
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m->offp = string;
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m->beginp = start;
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m->endp = stop;
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STATESETUP(m, 4);
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SETUP(m->st);
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SETUP(m->fresh);
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SETUP(m->tmp);
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SETUP(m->empty);
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CLEAR(m->empty);
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/* this loop does only one repetition except for backrefs */
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for (;;) {
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endp = fast(m, start, stop, gf, gl);
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if (endp == NULL) { /* a miss */
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free(m->pmatch);
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free((void*)m->lastpos);
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STATETEARDOWN(m);
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return(REG_NOMATCH);
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}
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if (nmatch == 0 && !g->backrefs)
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break; /* no further info needed */
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/* where? */
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assert(m->coldp != NULL);
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for (;;) {
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NOTE("finding start");
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endp = slow(m, m->coldp, stop, gf, gl);
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if (endp != NULL)
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break;
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assert(m->coldp < m->endp);
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m->coldp++;
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}
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if (nmatch == 1 && !g->backrefs)
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break; /* no further info needed */
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/* oh my, he wants the subexpressions... */
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if (m->pmatch == NULL)
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m->pmatch = (llvm_regmatch_t *)malloc((m->g->nsub + 1) *
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sizeof(llvm_regmatch_t));
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if (m->pmatch == NULL) {
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STATETEARDOWN(m);
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return(REG_ESPACE);
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}
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for (i = 1; i <= m->g->nsub; i++)
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m->pmatch[i].rm_so = m->pmatch[i].rm_eo = -1;
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if (!g->backrefs && !(m->eflags®_BACKR)) {
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NOTE("dissecting");
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dp = dissect(m, m->coldp, endp, gf, gl);
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} else {
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if (g->nplus > 0 && m->lastpos == NULL)
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m->lastpos = (const char **)malloc((g->nplus+1) *
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sizeof(char *));
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if (g->nplus > 0 && m->lastpos == NULL) {
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free(m->pmatch);
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STATETEARDOWN(m);
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return(REG_ESPACE);
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}
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NOTE("backref dissect");
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dp = backref(m, m->coldp, endp, gf, gl, (sopno)0, 0);
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}
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if (dp != NULL)
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break;
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/* uh-oh... we couldn't find a subexpression-level match */
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assert(g->backrefs); /* must be back references doing it */
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assert(g->nplus == 0 || m->lastpos != NULL);
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for (;;) {
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if (dp != NULL || endp <= m->coldp)
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break; /* defeat */
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NOTE("backoff");
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endp = slow(m, m->coldp, endp-1, gf, gl);
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if (endp == NULL)
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break; /* defeat */
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/* try it on a shorter possibility */
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#ifndef NDEBUG
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for (i = 1; i <= m->g->nsub; i++) {
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assert(m->pmatch[i].rm_so == -1);
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assert(m->pmatch[i].rm_eo == -1);
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}
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#endif
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NOTE("backoff dissect");
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dp = backref(m, m->coldp, endp, gf, gl, (sopno)0, 0);
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}
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assert(dp == NULL || dp == endp);
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if (dp != NULL) /* found a shorter one */
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break;
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/* despite initial appearances, there is no match here */
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NOTE("false alarm");
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if (m->coldp == stop)
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break;
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start = m->coldp + 1; /* recycle starting later */
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}
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/* fill in the details if requested */
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if (nmatch > 0) {
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pmatch[0].rm_so = m->coldp - m->offp;
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pmatch[0].rm_eo = endp - m->offp;
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}
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if (nmatch > 1) {
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assert(m->pmatch != NULL);
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for (i = 1; i < nmatch; i++)
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if (i <= m->g->nsub)
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pmatch[i] = m->pmatch[i];
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else {
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pmatch[i].rm_so = -1;
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pmatch[i].rm_eo = -1;
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}
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}
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if (m->pmatch != NULL)
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free((char *)m->pmatch);
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if (m->lastpos != NULL)
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free((char *)m->lastpos);
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STATETEARDOWN(m);
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return(0);
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}
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/*
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- dissect - figure out what matched what, no back references
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*/
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static const char * /* == stop (success) always */
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dissect(struct match *m, const char *start, const char *stop, sopno startst,
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sopno stopst)
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{
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int i;
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sopno ss; /* start sop of current subRE */
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sopno es; /* end sop of current subRE */
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const char *sp; /* start of string matched by it */
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const char *stp; /* string matched by it cannot pass here */
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const char *rest; /* start of rest of string */
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const char *tail; /* string unmatched by rest of RE */
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sopno ssub; /* start sop of subsubRE */
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sopno esub; /* end sop of subsubRE */
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const char *ssp; /* start of string matched by subsubRE */
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const char *sep; /* end of string matched by subsubRE */
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const char *oldssp; /* previous ssp */
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AT("diss", start, stop, startst, stopst);
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sp = start;
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for (ss = startst; ss < stopst; ss = es) {
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/* identify end of subRE */
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es = ss;
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switch (OP(m->g->strip[es])) {
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case OPLUS_:
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case OQUEST_:
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es += OPND(m->g->strip[es]);
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break;
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case OCH_:
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while (OP(m->g->strip[es]) != O_CH)
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es += OPND(m->g->strip[es]);
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break;
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}
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es++;
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/* figure out what it matched */
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switch (OP(m->g->strip[ss])) {
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case OEND:
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assert(nope);
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break;
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case OCHAR:
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sp++;
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break;
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case OBOL:
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case OEOL:
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case OBOW:
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case OEOW:
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break;
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case OANY:
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case OANYOF:
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sp++;
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break;
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case OBACK_:
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case O_BACK:
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assert(nope);
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break;
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/* cases where length of match is hard to find */
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case OQUEST_:
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stp = stop;
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for (;;) {
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/* how long could this one be? */
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rest = slow(m, sp, stp, ss, es);
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assert(rest != NULL); /* it did match */
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/* could the rest match the rest? */
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tail = slow(m, rest, stop, es, stopst);
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if (tail == stop)
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break; /* yes! */
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/* no -- try a shorter match for this one */
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stp = rest - 1;
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assert(stp >= sp); /* it did work */
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}
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ssub = ss + 1;
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esub = es - 1;
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/* did innards match? */
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if (slow(m, sp, rest, ssub, esub) != NULL) {
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const char *dp = dissect(m, sp, rest, ssub, esub);
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(void)dp; /* avoid warning if assertions off */
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assert(dp == rest);
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} else /* no */
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assert(sp == rest);
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sp = rest;
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break;
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case OPLUS_:
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stp = stop;
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for (;;) {
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/* how long could this one be? */
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rest = slow(m, sp, stp, ss, es);
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assert(rest != NULL); /* it did match */
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/* could the rest match the rest? */
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tail = slow(m, rest, stop, es, stopst);
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if (tail == stop)
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break; /* yes! */
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/* no -- try a shorter match for this one */
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stp = rest - 1;
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assert(stp >= sp); /* it did work */
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}
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ssub = ss + 1;
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esub = es - 1;
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ssp = sp;
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oldssp = ssp;
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for (;;) { /* find last match of innards */
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sep = slow(m, ssp, rest, ssub, esub);
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if (sep == NULL || sep == ssp)
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break; /* failed or matched null */
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oldssp = ssp; /* on to next try */
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ssp = sep;
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}
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if (sep == NULL) {
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/* last successful match */
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sep = ssp;
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ssp = oldssp;
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}
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assert(sep == rest); /* must exhaust substring */
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assert(slow(m, ssp, sep, ssub, esub) == rest);
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{
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const char *dp = dissect(m, ssp, sep, ssub, esub);
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(void)dp; /* avoid warning if assertions off */
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assert(dp == sep);
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}
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sp = rest;
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break;
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case OCH_:
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stp = stop;
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for (;;) {
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/* how long could this one be? */
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rest = slow(m, sp, stp, ss, es);
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assert(rest != NULL); /* it did match */
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/* could the rest match the rest? */
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tail = slow(m, rest, stop, es, stopst);
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if (tail == stop)
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break; /* yes! */
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/* no -- try a shorter match for this one */
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stp = rest - 1;
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assert(stp >= sp); /* it did work */
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}
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ssub = ss + 1;
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esub = ss + OPND(m->g->strip[ss]) - 1;
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assert(OP(m->g->strip[esub]) == OOR1);
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for (;;) { /* find first matching branch */
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if (slow(m, sp, rest, ssub, esub) == rest)
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break; /* it matched all of it */
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/* that one missed, try next one */
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assert(OP(m->g->strip[esub]) == OOR1);
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esub++;
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assert(OP(m->g->strip[esub]) == OOR2);
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ssub = esub + 1;
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esub += OPND(m->g->strip[esub]);
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if (OP(m->g->strip[esub]) == OOR2)
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esub--;
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else
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assert(OP(m->g->strip[esub]) == O_CH);
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}
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{
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const char *dp = dissect(m, sp, rest, ssub, esub);
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(void)dp; /* avoid warning if assertions off */
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assert(dp == rest);
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}
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sp = rest;
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break;
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case O_PLUS:
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case O_QUEST:
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case OOR1:
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case OOR2:
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case O_CH:
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assert(nope);
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break;
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case OLPAREN:
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i = OPND(m->g->strip[ss]);
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assert(0 < i && i <= m->g->nsub);
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m->pmatch[i].rm_so = sp - m->offp;
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break;
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case ORPAREN:
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i = OPND(m->g->strip[ss]);
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assert(0 < i && i <= m->g->nsub);
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m->pmatch[i].rm_eo = sp - m->offp;
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break;
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default: /* uh oh */
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assert(nope);
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break;
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}
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}
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assert(sp == stop);
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return(sp);
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}
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|
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/*
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- backref - figure out what matched what, figuring in back references
|
|
*/
|
|
static const char * /* == stop (success) or NULL (failure) */
|
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backref(struct match *m, const char *start, const char *stop, sopno startst,
|
|
sopno stopst, sopno lev, int rec) /* PLUS nesting level */
|
|
{
|
|
int i;
|
|
sopno ss; /* start sop of current subRE */
|
|
const char *sp; /* start of string matched by it */
|
|
sopno ssub; /* start sop of subsubRE */
|
|
sopno esub; /* end sop of subsubRE */
|
|
const char *ssp; /* start of string matched by subsubRE */
|
|
const char *dp;
|
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size_t len;
|
|
int hard;
|
|
sop s;
|
|
llvm_regoff_t offsave;
|
|
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;
|
|
if (len == 0 && rec++ > MAX_RECURSION)
|
|
return(NULL);
|
|
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, rec));
|
|
break;
|
|
case OQUEST_: /* to null or not */
|
|
dp = backref(m, sp, stop, ss+1, stopst, lev, rec);
|
|
if (dp != NULL)
|
|
return(dp); /* not */
|
|
return(backref(m, sp, stop, ss+OPND(s)+1, stopst, lev, rec));
|
|
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, rec));
|
|
break;
|
|
case O_PLUS:
|
|
if (sp == m->lastpos[lev]) /* last pass matched null */
|
|
return(backref(m, sp, stop, ss+1, stopst, lev-1, rec));
|
|
/* try another pass */
|
|
m->lastpos[lev] = sp;
|
|
dp = backref(m, sp, stop, ss-OPND(s)+1, stopst, lev, rec);
|
|
if (dp == NULL)
|
|
return(backref(m, sp, stop, ss+1, stopst, lev-1, rec));
|
|
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, rec);
|
|
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, rec);
|
|
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, rec);
|
|
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 NULL;
|
|
}
|
|
|
|
/*
|
|
- fast - step through the string at top speed
|
|
*/
|
|
static const char * /* where tentative match ended, or NULL */
|
|
fast(struct match *m, const char *start, const char *stop, sopno startst,
|
|
sopno stopst)
|
|
{
|
|
states st = m->st;
|
|
states fresh = m->fresh;
|
|
states tmp = m->tmp;
|
|
const char *p = start;
|
|
int c = (start == m->beginp) ? OUT : *(start-1);
|
|
int lastc; /* previous c */
|
|
int flagch;
|
|
int i;
|
|
const 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 const char * /* where it ended */
|
|
slow(struct match *m, const char *start, const char *stop, sopno startst,
|
|
sopno stopst)
|
|
{
|
|
states st = m->st;
|
|
states empty = m->empty;
|
|
states tmp = m->tmp;
|
|
const char *p = start;
|
|
int c = (start == m->beginp) ? OUT : *(start-1);
|
|
int lastc; /* previous c */
|
|
int flagch;
|
|
int i;
|
|
const 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(struct re_guts *g,
|
|
sopno start, /* start state within strip */
|
|
sopno stop, /* state after stop state within strip */
|
|
states bef, /* states reachable before */
|
|
int ch, /* character or NONCHAR code */
|
|
states aft) /* states already known reachable after */
|
|
{
|
|
cset *cs;
|
|
sop s;
|
|
sopno pc;
|
|
onestate here; /* note, macros know this name */
|
|
sopno look;
|
|
int i;
|
|
|
|
for (pc = start, INIT(here, pc); pc != stop; pc++, INC(here)) {
|
|
s = g->strip[pc];
|
|
switch (OP(s)) {
|
|
case OEND:
|
|
assert(pc == stop-1);
|
|
break;
|
|
case OCHAR:
|
|
/* only characters can match */
|
|
assert(!NONCHAR(ch) || ch != (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
|
|
*/
|
|
static void
|
|
print(struct match *m, char *caption, states st, int ch, FILE *d)
|
|
{
|
|
struct re_guts *g = m->g;
|
|
int i;
|
|
int first = 1;
|
|
|
|
if (!(m->eflags®_TRACE))
|
|
return;
|
|
|
|
(void)fprintf(d, "%s", caption);
|
|
if (ch != '\0')
|
|
(void)fprintf(d, " %s", pchar(ch));
|
|
for (i = 0; i < g->nstates; i++)
|
|
if (ISSET(st, i)) {
|
|
(void)fprintf(d, "%s%d", (first) ? "\t" : ", ", i);
|
|
first = 0;
|
|
}
|
|
(void)fprintf(d, "\n");
|
|
}
|
|
|
|
/*
|
|
- at - print current situation
|
|
*/
|
|
static void
|
|
at(struct match *m, char *title, char *start, char *stop, sopno startst,
|
|
sopno stopst)
|
|
{
|
|
if (!(m->eflags®_TRACE))
|
|
return;
|
|
|
|
(void)printf("%s %s-", title, pchar(*start));
|
|
(void)printf("%s ", pchar(*stop));
|
|
(void)printf("%ld-%ld\n", (long)startst, (long)stopst);
|
|
}
|
|
|
|
#ifndef PCHARDONE
|
|
#define PCHARDONE /* never again */
|
|
/*
|
|
- pchar - make a character printable
|
|
*
|
|
* 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(int ch)
|
|
{
|
|
static char pbuf[10];
|
|
|
|
if (isprint(ch) || ch == ' ')
|
|
(void)snprintf(pbuf, sizeof pbuf, "%c", ch);
|
|
else
|
|
(void)snprintf(pbuf, sizeof 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
|
|
#undef nope
|