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--- Libc/Libc-262.3.2/regex/regcomp.c
+++ /dev/null
@@ -1,1715 +0,0 @@
-/*
- * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- *
- * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
- */
-/*
- * Copyright (c) 1992, 1993, 1994
- * The Regents of the University of California. All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Henry Spencer.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by the University of
- * California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#include <sys/types.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <limits.h>
-#include <stdlib.h>
-#include <regex.h>
-
-#include "utils.h"
-#include "regex2.h"
-
-#include "cclass.h"
-#include "cname.h"
-
-/*
- * parse structure, passed up and down to avoid global variables and
- * other clumsinesses
- */
-struct parse {
- char *next; /* next character in RE */
- char *end; /* end of string (-> NUL normally) */
- int error; /* has an error been seen? */
- sop *strip; /* malloced strip */
- sopno ssize; /* malloced strip size (allocated) */
- sopno slen; /* malloced strip length (used) */
- int ncsalloc; /* number of csets allocated */
- struct re_guts *g;
-# define NPAREN 10 /* we need to remember () 1-9 for back refs */
- sopno pbegin[NPAREN]; /* -> ( ([0] unused) */
- sopno pend[NPAREN]; /* -> ) ([0] unused) */
-};
-
-/* ========= begin header generated by ./mkh ========= */
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* === regcomp.c === */
-static void p_ere __P((struct parse *p, int stop));
-static void p_ere_exp __P((struct parse *p));
-static void p_str __P((struct parse *p));
-static void p_bre __P((struct parse *p, int end1, int end2));
-static int p_simp_re __P((struct parse *p, int starordinary));
-static int p_count __P((struct parse *p));
-static void p_bracket __P((struct parse *p));
-static void p_b_term __P((struct parse *p, cset *cs));
-static void p_b_cclass __P((struct parse *p, cset *cs));
-static void p_b_eclass __P((struct parse *p, cset *cs));
-static char p_b_symbol __P((struct parse *p));
-static char p_b_coll_elem __P((struct parse *p, int endc));
-static char othercase __P((int ch));
-static void bothcases __P((struct parse *p, int ch));
-static void ordinary __P((struct parse *p, int ch));
-static void nonnewline __P((struct parse *p));
-static void repeat __P((struct parse *p, sopno start, int from, int to));
-static int seterr __P((struct parse *p, int e));
-static cset *allocset __P((struct parse *p));
-static void freeset __P((struct parse *p, cset *cs));
-static int freezeset __P((struct parse *p, cset *cs));
-static int firstch __P((struct parse *p, cset *cs));
-static int nch __P((struct parse *p, cset *cs));
-static void mcadd __P((struct parse *p, cset *cs, char *cp));
-static void mcsub __P((cset *cs, char *cp));
-static int mcin __P((cset *cs, char *cp));
-static char *mcfind __P((cset *cs, char *cp));
-static void mcinvert __P((struct parse *p, cset *cs));
-static void mccase __P((struct parse *p, cset *cs));
-static int isinsets __P((struct re_guts *g, int c));
-static int samesets __P((struct re_guts *g, int c1, int c2));
-static void categorize __P((struct parse *p, struct re_guts *g));
-static sopno dupl __P((struct parse *p, sopno start, sopno finish));
-static void doemit __P((struct parse *p, sop op, size_t opnd));
-static void doinsert __P((struct parse *p, sop op, size_t opnd, sopno pos));
-static void dofwd __P((struct parse *p, sopno pos, sop value));
-static void enlarge __P((struct parse *p, sopno size));
-static void stripsnug __P((struct parse *p, struct re_guts *g));
-static void findmust __P((struct parse *p, struct re_guts *g));
-static sopno pluscount __P((struct parse *p, struct re_guts *g));
-
-#ifdef __cplusplus
-}
-#endif
-/* ========= end header generated by ./mkh ========= */
-
-static char nuls[10]; /* place to point scanner in event of error */
-
-/*
- * macros for use with parse structure
- * BEWARE: these know that the parse structure is named `p' !!!
- */
-#define PEEK() (*p->next)
-#define PEEK2() (*(p->next+1))
-#define MORE() (p->next < p->end)
-#define MORE2() (p->next+1 < p->end)
-#define SEE(c) (MORE() && PEEK() == (c))
-#define SEETWO(a, b) (MORE() && MORE2() && PEEK() == (a) && PEEK2() == (b))
-#define EAT(c) ((SEE(c)) ? (NEXT(), 1) : 0)
-#define EATTWO(a, b) ((SEETWO(a, b)) ? (NEXT2(), 1) : 0)
-#define NEXT() (p->next++)
-#define NEXT2() (p->next += 2)
-#define NEXTn(n) (p->next += (n))
-#define GETNEXT() (*p->next++)
-#define SETERROR(e) seterr(p, (e))
-#define REQUIRE(co, e) ((co) || SETERROR(e))
-#define MUSTSEE(c, e) (REQUIRE(MORE() && PEEK() == (c), e))
-#define MUSTEAT(c, e) (REQUIRE(MORE() && GETNEXT() == (c), e))
-#define MUSTNOTSEE(c, e) (REQUIRE(!MORE() || PEEK() != (c), e))
-#define EMIT(op, sopnd) doemit(p, (sop)(op), (size_t)(sopnd))
-#define INSERT(op, pos) doinsert(p, (sop)(op), HERE()-(pos)+1, pos)
-#define AHEAD(pos) dofwd(p, pos, HERE()-(pos))
-#define ASTERN(sop, pos) EMIT(sop, HERE()-pos)
-#define HERE() (p->slen)
-#define THERE() (p->slen - 1)
-#define THERETHERE() (p->slen - 2)
-#define DROP(n) (p->slen -= (n))
-
-#ifndef NDEBUG
-static int never = 0; /* for use in asserts; shuts lint up */
-#else
-#define never 0 /* some <assert.h>s have bugs too */
-#endif
-
-/*
- - regcomp - interface for parser and compilation
- = extern int regcomp(regex_t *, const char *, int);
- = #define REG_BASIC 0000
- = #define REG_EXTENDED 0001
- = #define REG_ICASE 0002
- = #define REG_NOSUB 0004
- = #define REG_NEWLINE 0010
- = #define REG_NOSPEC 0020
- = #define REG_PEND 0040
- = #define REG_DUMP 0200
- */
-int /* 0 success, otherwise REG_something */
-regcomp(preg, pattern, cflags)
-regex_t *preg;
-const char *pattern;
-int cflags;
-{
- struct parse pa;
- register struct re_guts *g;
- register struct parse *p = &pa;
- register int i;
- register size_t len;
-#ifdef REDEBUG
-# define GOODFLAGS(f) (f)
-#else
-# define GOODFLAGS(f) ((f)&~REG_DUMP)
-#endif
-
- cflags = GOODFLAGS(cflags);
- if ((cflags®_EXTENDED) && (cflags®_NOSPEC))
- return(REG_INVARG);
-
- if (cflags®_PEND) {
- if (preg->re_endp < pattern)
- return(REG_INVARG);
- len = preg->re_endp - pattern;
- } else
- len = strlen((char *)pattern);
-
- /* do the mallocs early so failure handling is easy */
- g = (struct re_guts *)malloc(sizeof(struct re_guts) +
- (NC-1)*sizeof(cat_t));
- if (g == NULL)
- return(REG_ESPACE);
- p->ssize = len/(size_t)2*(size_t)3 + (size_t)1; /* ugh */
- p->strip = (sop *)malloc(p->ssize * sizeof(sop));
- p->slen = 0;
- if (p->strip == NULL) {
- free((char *)g);
- return(REG_ESPACE);
- }
-
- /* set things up */
- p->g = g;
- p->next = (char *)pattern; /* convenience; we do not modify it */
- p->end = p->next + len;
- p->error = 0;
- p->ncsalloc = 0;
- for (i = 0; i < NPAREN; i++) {
- p->pbegin[i] = 0;
- p->pend[i] = 0;
- }
- g->csetsize = NC;
- g->sets = NULL;
- g->setbits = NULL;
- g->ncsets = 0;
- g->cflags = cflags;
- g->iflags = 0;
- g->nbol = 0;
- g->neol = 0;
- g->must = NULL;
- g->mlen = 0;
- g->nsub = 0;
- g->ncategories = 1; /* category 0 is "everything else" */
- g->categories = &g->catspace[-(CHAR_MIN)];
- (void) memset((char *)g->catspace, 0, NC*sizeof(cat_t));
- g->backrefs = 0;
-
- /* do it */
- EMIT(OEND, 0);
- g->firststate = THERE();
- if (cflags®_EXTENDED)
- p_ere(p, OUT);
- else if (cflags®_NOSPEC)
- p_str(p);
- else
- p_bre(p, OUT, OUT);
- EMIT(OEND, 0);
- g->laststate = THERE();
-
- /* tidy up loose ends and fill things in */
- categorize(p, g);
- stripsnug(p, g);
- findmust(p, g);
- g->nplus = pluscount(p, g);
- g->magic = MAGIC2;
- preg->re_nsub = g->nsub;
- preg->re_g = g;
- preg->re_magic = MAGIC1;
-#ifndef REDEBUG
- /* not debugging, so can't rely on the assert() in regexec() */
- if (g->iflags&BAD)
- SETERROR(REG_ASSERT);
-#endif
-
- /* win or lose, we're done */
- if (p->error != 0) /* lose */
- regfree(preg);
- return(p->error);
-}
-
-/*
- - p_ere - ERE parser top level, concatenation and alternation
- == static void p_ere(register struct parse *p, int stop);
- */
-static void
-p_ere(p, stop)
-register struct parse *p;
-int stop; /* character this ERE should end at */
-{
- register char c;
- register sopno prevback;
- register sopno prevfwd;
- register sopno conc;
- register int first = 1; /* is this the first alternative? */
-
- for (;;) {
- /* do a bunch of concatenated expressions */
- conc = HERE();
- while (MORE() && (c = PEEK()) != '|' && c != stop)
- p_ere_exp(p);
- REQUIRE(HERE() != conc, REG_EMPTY); /* require nonempty */
-
- if (!EAT('|'))
- break; /* NOTE BREAK OUT */
-
- if (first) {
- INSERT(OCH_, conc); /* offset is wrong */
- prevfwd = conc;
- prevback = conc;
- first = 0;
- }
- ASTERN(OOR1, prevback);
- prevback = THERE();
- AHEAD(prevfwd); /* fix previous offset */
- prevfwd = HERE();
- EMIT(OOR2, 0); /* offset is very wrong */
- }
-
- if (!first) { /* tail-end fixups */
- AHEAD(prevfwd);
- ASTERN(O_CH, prevback);
- }
-
- assert(!MORE() || SEE(stop));
-}
-
-/*
- - p_ere_exp - parse one subERE, an atom possibly followed by a repetition op
- == static void p_ere_exp(register struct parse *p);
- */
-static void
-p_ere_exp(p)
-register struct parse *p;
-{
- register char c;
- register sopno pos;
- register int count;
- register int count2;
- register sopno subno;
- int wascaret = 0;
-
- assert(MORE()); /* caller should have ensured this */
- c = GETNEXT();
-
- pos = HERE();
- switch (c) {
- case '(':
- REQUIRE(MORE(), REG_EPAREN);
- p->g->nsub++;
- subno = p->g->nsub;
- if (subno < NPAREN)
- p->pbegin[subno] = HERE();
- EMIT(OLPAREN, subno);
- if (!SEE(')'))
- p_ere(p, ')');
- if (subno < NPAREN) {
- p->pend[subno] = HERE();
- assert(p->pend[subno] != 0);
- }
- EMIT(ORPAREN, subno);
- MUSTEAT(')', REG_EPAREN);
- break;
-#ifndef POSIX_MISTAKE
- case ')': /* happens only if no current unmatched ( */
- /*
- * You may ask, why the ifndef? Because I didn't notice
- * this until slightly too late for 1003.2, and none of the
- * other 1003.2 regular-expression reviewers noticed it at
- * all. So an unmatched ) is legal POSIX, at least until
- * we can get it fixed.
- */
- SETERROR(REG_EPAREN);
- break;
-#endif
- case '^':
- EMIT(OBOL, 0);
- p->g->iflags |= USEBOL;
- p->g->nbol++;
- wascaret = 1;
- break;
- case '$':
- EMIT(OEOL, 0);
- p->g->iflags |= USEEOL;
- p->g->neol++;
- break;
- case '|':
- SETERROR(REG_EMPTY);
- break;
- case '*':
- case '+':
- case '?':
- SETERROR(REG_BADRPT);
- break;
- case '.':
- if (p->g->cflags®_NEWLINE)
- nonnewline(p);
- else
- EMIT(OANY, 0);
- break;
- case '[':
- p_bracket(p);
- break;
- case '\\':
- REQUIRE(MORE(), REG_EESCAPE);
- c = GETNEXT();
- ordinary(p, c);
- break;
- case '{': /* okay as ordinary except if digit follows */
- REQUIRE(!MORE() || !isdigit(PEEK()), REG_BADRPT);
- /* FALLTHROUGH */
- default:
- ordinary(p, c);
- break;
- }
-
- if (!MORE())
- return;
- c = PEEK();
- /* we call { a repetition if followed by a digit */
- if (!( c == '*' || c == '+' || c == '?' ||
- (c == '{' && MORE2() && isdigit(PEEK2())) ))
- return; /* no repetition, we're done */
- NEXT();
-
- REQUIRE(!wascaret, REG_BADRPT);
- switch (c) {
- case '*': /* implemented as +? */
- /* this case does not require the (y|) trick, noKLUDGE */
- INSERT(OPLUS_, pos);
- ASTERN(O_PLUS, pos);
- INSERT(OQUEST_, pos);
- ASTERN(O_QUEST, pos);
- break;
- case '+':
- INSERT(OPLUS_, pos);
- ASTERN(O_PLUS, pos);
- break;
- case '?':
- /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */
- INSERT(OCH_, pos); /* offset slightly wrong */
- ASTERN(OOR1, pos); /* this one's right */
- AHEAD(pos); /* fix the OCH_ */
- EMIT(OOR2, 0); /* offset very wrong... */
- AHEAD(THERE()); /* ...so fix it */
- ASTERN(O_CH, THERETHERE());
- break;
- case '{':
- count = p_count(p);
- if (EAT(',')) {
- if (isdigit(PEEK())) {
- count2 = p_count(p);
- REQUIRE(count <= count2, REG_BADBR);
- } else /* single number with comma */
- count2 = INFINITY;
- } else /* just a single number */
- count2 = count;
- repeat(p, pos, count, count2);
- if (!EAT('}')) { /* error heuristics */
- while (MORE() && PEEK() != '}')
- NEXT();
- REQUIRE(MORE(), REG_EBRACE);
- SETERROR(REG_BADBR);
- }
- break;
- }
-
- if (!MORE())
- return;
- c = PEEK();
- if (!( c == '*' || c == '+' || c == '?' ||
- (c == '{' && MORE2() && isdigit(PEEK2())) ) )
- return;
- SETERROR(REG_BADRPT);
-}
-
-/*
- - p_str - string (no metacharacters) "parser"
- == static void p_str(register struct parse *p);
- */
-static void
-p_str(p)
-register struct parse *p;
-{
- REQUIRE(MORE(), REG_EMPTY);
- while (MORE())
- ordinary(p, GETNEXT());
-}
-
-/*
- - p_bre - BRE parser top level, anchoring and concatenation
- == static void p_bre(register struct parse *p, register int end1, \
- == register int end2);
- * Giving end1 as OUT essentially eliminates the end1/end2 check.
- *
- * This implementation is a bit of a kludge, in that a trailing $ is first
- * taken as an ordinary character and then revised to be an anchor. The
- * only undesirable side effect is that '$' gets included as a character
- * category in such cases. This is fairly harmless; not worth fixing.
- * The amount of lookahead needed to avoid this kludge is excessive.
- */
-static void
-p_bre(p, end1, end2)
-register struct parse *p;
-register int end1; /* first terminating character */
-register int end2; /* second terminating character */
-{
- register sopno start = HERE();
- register int first = 1; /* first subexpression? */
- register int wasdollar = 0;
-
- if (EAT('^')) {
- EMIT(OBOL, 0);
- p->g->iflags |= USEBOL;
- p->g->nbol++;
- }
- while (MORE() && !SEETWO(end1, end2)) {
- wasdollar = p_simp_re(p, first);
- first = 0;
- }
- if (wasdollar) { /* oops, that was a trailing anchor */
- DROP(1);
- EMIT(OEOL, 0);
- p->g->iflags |= USEEOL;
- p->g->neol++;
- }
-
- REQUIRE(HERE() != start, REG_EMPTY); /* require nonempty */
-}
-
-/*
- - p_simp_re - parse a simple RE, an atom possibly followed by a repetition
- == static int p_simp_re(register struct parse *p, int starordinary);
- */
-static int /* was the simple RE an unbackslashed $? */
-p_simp_re(p, starordinary)
-register struct parse *p;
-int starordinary; /* is a leading * an ordinary character? */
-{
- register int c;
- register int count;
- register int count2;
- register sopno pos;
- register int i;
- register sopno subno;
-# define BACKSL (1<<CHAR_BIT)
-
- pos = HERE(); /* repetion op, if any, covers from here */
-
- assert(MORE()); /* caller should have ensured this */
- c = GETNEXT();
- if (c == '\\') {
- REQUIRE(MORE(), REG_EESCAPE);
- c = BACKSL | (unsigned char)GETNEXT();
- }
- switch (c) {
- case '.':
- if (p->g->cflags®_NEWLINE)
- nonnewline(p);
- else
- EMIT(OANY, 0);
- break;
- case '[':
- p_bracket(p);
- break;
- case BACKSL|'{':
- SETERROR(REG_BADRPT);
- break;
- case BACKSL|'(':
- p->g->nsub++;
- subno = p->g->nsub;
- if (subno < NPAREN)
- p->pbegin[subno] = HERE();
- EMIT(OLPAREN, subno);
- /* the MORE here is an error heuristic */
- if (MORE() && !SEETWO('\\', ')'))
- p_bre(p, '\\', ')');
- if (subno < NPAREN) {
- p->pend[subno] = HERE();
- assert(p->pend[subno] != 0);
- }
- EMIT(ORPAREN, subno);
- REQUIRE(EATTWO('\\', ')'), REG_EPAREN);
- break;
- case BACKSL|')': /* should not get here -- must be user */
- case BACKSL|'}':
- SETERROR(REG_EPAREN);
- break;
- case BACKSL|'1':
- case BACKSL|'2':
- case BACKSL|'3':
- case BACKSL|'4':
- case BACKSL|'5':
- case BACKSL|'6':
- case BACKSL|'7':
- case BACKSL|'8':
- case BACKSL|'9':
- i = (c&~BACKSL) - '0';
- assert(i < NPAREN);
- if (p->pend[i] != 0) {
- assert(i <= p->g->nsub);
- EMIT(OBACK_, i);
- assert(p->pbegin[i] != 0);
- assert(OP(p->strip[p->pbegin[i]]) == OLPAREN);
- assert(OP(p->strip[p->pend[i]]) == ORPAREN);
- (void) dupl(p, p->pbegin[i]+1, p->pend[i]);
- EMIT(O_BACK, i);
- } else
- SETERROR(REG_ESUBREG);
- p->g->backrefs = 1;
- break;
- case '*':
- REQUIRE(starordinary, REG_BADRPT);
- /* FALLTHROUGH */
- default:
- ordinary(p, c &~ BACKSL);
- break;
- }
-
- if (EAT('*')) { /* implemented as +? */
- /* this case does not require the (y|) trick, noKLUDGE */
- INSERT(OPLUS_, pos);
- ASTERN(O_PLUS, pos);
- INSERT(OQUEST_, pos);
- ASTERN(O_QUEST, pos);
- } else if (EATTWO('\\', '{')) {
- count = p_count(p);
- if (EAT(',')) {
- if (MORE() && isdigit(PEEK())) {
- count2 = p_count(p);
- REQUIRE(count <= count2, REG_BADBR);
- } else /* single number with comma */
- count2 = INFINITY;
- } else /* just a single number */
- count2 = count;
- repeat(p, pos, count, count2);
- if (!EATTWO('\\', '}')) { /* error heuristics */
- while (MORE() && !SEETWO('\\', '}'))
- NEXT();
- REQUIRE(MORE(), REG_EBRACE);
- SETERROR(REG_BADBR);
- }
- } else if (c == (unsigned char)'$') /* $ (but not \$) ends it */
- return(1);
-
- return(0);
-}
-
-/*
- - p_count - parse a repetition count
- == static int p_count(register struct parse *p);
- */
-static int /* the value */
-p_count(p)
-register struct parse *p;
-{
- register int count = 0;
- register int ndigits = 0;
-
- while (MORE() && isdigit(PEEK()) && count <= DUPMAX) {
- count = count*10 + (GETNEXT() - '0');
- ndigits++;
- }
-
- REQUIRE(ndigits > 0 && count <= DUPMAX, REG_BADBR);
- return(count);
-}
-
-/*
- - p_bracket - parse a bracketed character list
- == static void p_bracket(register struct parse *p);
- *
- * Note a significant property of this code: if the allocset() did SETERROR,
- * no set operations are done.
- */
-static void
-p_bracket(p)
-register struct parse *p;
-{
- register char c;
- register cset *cs = allocset(p);
- register int invert = 0;
-
- /* Dept of Truly Sickening Special-Case Kludges */
- if (p->next + 5 < p->end && strncmp(p->next, "[:<:]]", 6) == 0) {
- EMIT(OBOW, 0);
- NEXTn(6);
- return;
- }
- if (p->next + 5 < p->end && strncmp(p->next, "[:>:]]", 6) == 0) {
- EMIT(OEOW, 0);
- NEXTn(6);
- return;
- }
-
- if (EAT('^'))
- invert++; /* make note to invert set at end */
- if (EAT(']'))
- CHadd(cs, ']');
- else if (EAT('-'))
- CHadd(cs, '-');
- while (MORE() && PEEK() != ']' && !SEETWO('-', ']'))
- p_b_term(p, cs);
- if (EAT('-'))
- CHadd(cs, '-');
- MUSTEAT(']', REG_EBRACK);
-
- if (p->error != 0) /* don't mess things up further */
- return;
-
- if (p->g->cflags®_ICASE) {
- register int i;
- register int ci;
-
- for (i = p->g->csetsize - 1; i >= 0; i--)
- if (CHIN(cs, i) && isalpha(i)) {
- ci = othercase(i);
- if (ci != i)
- CHadd(cs, ci);
- }
- if (cs->multis != NULL)
- mccase(p, cs);
- }
- if (invert) {
- register int i;
-
- for (i = p->g->csetsize - 1; i >= 0; i--)
- if (CHIN(cs, i))
- CHsub(cs, i);
- else
- CHadd(cs, i);
- if (p->g->cflags®_NEWLINE)
- CHsub(cs, '\n');
- if (cs->multis != NULL)
- mcinvert(p, cs);
- }
-
- assert(cs->multis == NULL); /* xxx */
-
- if (nch(p, cs) == 1) { /* optimize singleton sets */
- ordinary(p, firstch(p, cs));
- freeset(p, cs);
- } else
- EMIT(OANYOF, freezeset(p, cs));
-}
-
-/*
- - p_b_term - parse one term of a bracketed character list
- == static void p_b_term(register struct parse *p, register cset *cs);
- */
-static void
-p_b_term(p, cs)
-register struct parse *p;
-register cset *cs;
-{
- register char c;
- register char start, finish;
- register int i;
-
- /* classify what we've got */
- switch ((MORE()) ? PEEK() : '\0') {
- case '[':
- c = (MORE2()) ? PEEK2() : '\0';
- break;
- case '-':
- SETERROR(REG_ERANGE);
- return; /* NOTE RETURN */
- break;
- default:
- c = '\0';
- break;
- }
-
- switch (c) {
- case ':': /* character class */
- NEXT2();
- REQUIRE(MORE(), REG_EBRACK);
- c = PEEK();
- REQUIRE(c != '-' && c != ']', REG_ECTYPE);
- p_b_cclass(p, cs);
- REQUIRE(MORE(), REG_EBRACK);
- REQUIRE(EATTWO(':', ']'), REG_ECTYPE);
- break;
- case '=': /* equivalence class */
- NEXT2();
- REQUIRE(MORE(), REG_EBRACK);
- c = PEEK();
- REQUIRE(c != '-' && c != ']', REG_ECOLLATE);
- p_b_eclass(p, cs);
- REQUIRE(MORE(), REG_EBRACK);
- REQUIRE(EATTWO('=', ']'), REG_ECOLLATE);
- break;
- default: /* symbol, ordinary character, or range */
-/* xxx revision needed for multichar stuff */
- start = p_b_symbol(p);
- if (SEE('-') && MORE2() && PEEK2() != ']') {
- /* range */
- NEXT();
- if (EAT('-'))
- finish = '-';
- else
- finish = p_b_symbol(p);
- } else
- finish = start;
-/* xxx what about signed chars here... */
- REQUIRE(start <= finish, REG_ERANGE);
- for (i = start; i <= finish; i++)
- CHadd(cs, i);
- break;
- }
-}
-
-/*
- - p_b_cclass - parse a character-class name and deal with it
- == static void p_b_cclass(register struct parse *p, register cset *cs);
- */
-static void
-p_b_cclass(p, cs)
-register struct parse *p;
-register cset *cs;
-{
- register char *sp = p->next;
- register struct cclass *cp;
- register size_t len;
- register char *u;
- register char c;
-
- while (MORE() && isalpha(PEEK()))
- NEXT();
- len = p->next - sp;
- for (cp = cclasses; cp->name != NULL; cp++)
- if (strncmp(cp->name, sp, len) == 0 && cp->name[len] == '\0')
- break;
- if (cp->name == NULL) {
- /* oops, didn't find it */
- SETERROR(REG_ECTYPE);
- return;
- }
-
- u = cp->chars;
- while ((c = *u++) != '\0')
- CHadd(cs, c);
- for (u = cp->multis; *u != '\0'; u += strlen(u) + 1)
- MCadd(p, cs, u);
-}
-
-/*
- - p_b_eclass - parse an equivalence-class name and deal with it
- == static void p_b_eclass(register struct parse *p, register cset *cs);
- *
- * This implementation is incomplete. xxx
- */
-static void
-p_b_eclass(p, cs)
-register struct parse *p;
-register cset *cs;
-{
- register char c;
-
- c = p_b_coll_elem(p, '=');
- CHadd(cs, c);
-}
-
-/*
- - p_b_symbol - parse a character or [..]ed multicharacter collating symbol
- == static char p_b_symbol(register struct parse *p);
- */
-static char /* value of symbol */
-p_b_symbol(p)
-register struct parse *p;
-{
- register char value;
-
- REQUIRE(MORE(), REG_EBRACK);
- if (!EATTWO('[', '.'))
- return(GETNEXT());
-
- /* collating symbol */
- value = p_b_coll_elem(p, '.');
- REQUIRE(EATTWO('.', ']'), REG_ECOLLATE);
- return(value);
-}
-
-/*
- - p_b_coll_elem - parse a collating-element name and look it up
- == static char p_b_coll_elem(register struct parse *p, int endc);
- */
-static char /* value of collating element */
-p_b_coll_elem(p, endc)
-register struct parse *p;
-int endc; /* name ended by endc,']' */
-{
- register char *sp = p->next;
- register struct cname *cp;
- register int len;
- register char c;
-
- while (MORE() && !SEETWO(endc, ']'))
- NEXT();
- if (!MORE()) {
- SETERROR(REG_EBRACK);
- return(0);
- }
- len = p->next - sp;
- for (cp = cnames; cp->name != NULL; cp++)
- if (strncmp(cp->name, sp, len) == 0 && cp->name[len] == '\0')
- return(cp->code); /* known name */
- if (len == 1)
- return(*sp); /* single character */
- SETERROR(REG_ECOLLATE); /* neither */
- return(0);
-}
-
-/*
- - othercase - return the case counterpart of an alphabetic
- == static char othercase(int ch);
- */
-static char /* if no counterpart, return ch */
-othercase(ch)
-int ch;
-{
- assert(isalpha(ch));
- if (isupper(ch))
- return(tolower(ch));
- else if (islower(ch))
- return(toupper(ch));
- else /* peculiar, but could happen */
- return(ch);
-}
-
-/*
- - bothcases - emit a dualcase version of a two-case character
- == static void bothcases(register struct parse *p, int ch);
- *
- * Boy, is this implementation ever a kludge...
- */
-static void
-bothcases(p, ch)
-register struct parse *p;
-int ch;
-{
- register char *oldnext = p->next;
- register char *oldend = p->end;
- char bracket[3];
-
- assert(othercase(ch) != ch); /* p_bracket() would recurse */
- p->next = bracket;
- p->end = bracket+2;
- bracket[0] = ch;
- bracket[1] = ']';
- bracket[2] = '\0';
- p_bracket(p);
- assert(p->next == bracket+2);
- p->next = oldnext;
- p->end = oldend;
-}
-
-/*
- - ordinary - emit an ordinary character
- == static void ordinary(register struct parse *p, register int ch);
- */
-static void
-ordinary(p, ch)
-register struct parse *p;
-register int ch;
-{
- register cat_t *cap = p->g->categories;
-
- if ((p->g->cflags®_ICASE) && isalpha(ch) && othercase(ch) != ch)
- bothcases(p, ch);
- else {
- EMIT(OCHAR, (unsigned char)ch);
- if (cap[ch] == 0)
- cap[ch] = p->g->ncategories++;
- }
-}
-
-/*
- - nonnewline - emit REG_NEWLINE version of OANY
- == static void nonnewline(register struct parse *p);
- *
- * Boy, is this implementation ever a kludge...
- */
-static void
-nonnewline(p)
-register struct parse *p;
-{
- register char *oldnext = p->next;
- register char *oldend = p->end;
- char bracket[4];
-
- p->next = bracket;
- p->end = bracket+3;
- bracket[0] = '^';
- bracket[1] = '\n';
- bracket[2] = ']';
- bracket[3] = '\0';
- p_bracket(p);
- assert(p->next == bracket+3);
- p->next = oldnext;
- p->end = oldend;
-}
-
-/*
- - repeat - generate code for a bounded repetition, recursively if needed
- == static void repeat(register struct parse *p, sopno start, int from, int to);
- */
-static void
-repeat(p, start, from, to)
-register struct parse *p;
-sopno start; /* operand from here to end of strip */
-int from; /* repeated from this number */
-int to; /* to this number of times (maybe INFINITY) */
-{
- register sopno finish = HERE();
-# define N 2
-# define INF 3
-# define REP(f, t) ((f)*8 + (t))
-# define MAP(n) (((n) <= 1) ? (n) : ((n) == INFINITY) ? INF : N)
- register sopno copy;
-
- if (p->error != 0) /* head off possible runaway recursion */
- return;
-
- assert(from <= to);
-
- switch (REP(MAP(from), MAP(to))) {
- case REP(0, 0): /* must be user doing this */
- DROP(finish-start); /* drop the operand */
- break;
- case REP(0, 1): /* as x{1,1}? */
- case REP(0, N): /* as x{1,n}? */
- case REP(0, INF): /* as x{1,}? */
- /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */
- INSERT(OCH_, start); /* offset is wrong... */
- repeat(p, start+1, 1, to);
- ASTERN(OOR1, start);
- AHEAD(start); /* ... fix it */
- EMIT(OOR2, 0);
- AHEAD(THERE());
- ASTERN(O_CH, THERETHERE());
- break;
- case REP(1, 1): /* trivial case */
- /* done */
- break;
- case REP(1, N): /* as x?x{1,n-1} */
- /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */
- INSERT(OCH_, start);
- ASTERN(OOR1, start);
- AHEAD(start);
- EMIT(OOR2, 0); /* offset very wrong... */
- AHEAD(THERE()); /* ...so fix it */
- ASTERN(O_CH, THERETHERE());
- copy = dupl(p, start+1, finish+1);
- assert(copy == finish+4);
- repeat(p, copy, 1, to-1);
- break;
- case REP(1, INF): /* as x+ */
- INSERT(OPLUS_, start);
- ASTERN(O_PLUS, start);
- break;
- case REP(N, N): /* as xx{m-1,n-1} */
- copy = dupl(p, start, finish);
- repeat(p, copy, from-1, to-1);
- break;
- case REP(N, INF): /* as xx{n-1,INF} */
- copy = dupl(p, start, finish);
- repeat(p, copy, from-1, to);
- break;
- default: /* "can't happen" */
- SETERROR(REG_ASSERT); /* just in case */
- break;
- }
-}
-
-/*
- - seterr - set an error condition
- == static int seterr(register struct parse *p, int e);
- */
-static int /* useless but makes type checking happy */
-seterr(p, e)
-register struct parse *p;
-int e;
-{
- if (p->error == 0) /* keep earliest error condition */
- p->error = e;
- p->next = nuls; /* try to bring things to a halt */
- p->end = nuls;
- return(0); /* make the return value well-defined */
-}
-
-/*
- - allocset - allocate a set of characters for []
- == static cset *allocset(register struct parse *p);
- */
-static cset *
-allocset(p)
-register struct parse *p;
-{
- register int no = p->g->ncsets++;
- register size_t nc;
- register size_t nbytes;
- register cset *cs;
- register size_t css = (size_t)p->g->csetsize;
- register int i;
-
- if (no >= p->ncsalloc) { /* need another column of space */
- p->ncsalloc += CHAR_BIT;
- nc = p->ncsalloc;
- assert(nc % CHAR_BIT == 0);
- nbytes = nc / CHAR_BIT * css;
- if (p->g->sets == NULL)
- p->g->sets = (cset *)malloc(nc * sizeof(cset));
- else
- p->g->sets = (cset *)realloc((char *)p->g->sets,
- nc * sizeof(cset));
- if (p->g->setbits == NULL)
- p->g->setbits = (uch *)malloc(nbytes);
- else {
- p->g->setbits = (uch *)realloc((char *)p->g->setbits,
- nbytes);
- /* xxx this isn't right if setbits is now NULL */
- for (i = 0; i < no; i++)
- p->g->sets[i].ptr = p->g->setbits + css*(i/CHAR_BIT);
- }
- if (p->g->sets != NULL && p->g->setbits != NULL)
- (void) memset((char *)p->g->setbits + (nbytes - css),
- 0, css);
- else {
- no = 0;
- SETERROR(REG_ESPACE);
- /* caller's responsibility not to do set ops */
- }
- }
-
- assert(p->g->sets != NULL); /* xxx */
- cs = &p->g->sets[no];
- cs->ptr = p->g->setbits + css*((no)/CHAR_BIT);
- cs->mask = 1 << ((no) % CHAR_BIT);
- cs->hash = 0;
- cs->smultis = 0;
- cs->multis = NULL;
-
- return(cs);
-}
-
-/*
- - freeset - free a now-unused set
- == static void freeset(register struct parse *p, register cset *cs);
- */
-static void
-freeset(p, cs)
-register struct parse *p;
-register cset *cs;
-{
- register int i;
- register cset *top = &p->g->sets[p->g->ncsets];
- register size_t css = (size_t)p->g->csetsize;
-
- for (i = 0; i < css; i++)
- CHsub(cs, i);
- if (cs == top-1) /* recover only the easy case */
- p->g->ncsets--;
-}
-
-/*
- - freezeset - final processing on a set of characters
- == static int freezeset(register struct parse *p, register cset *cs);
- *
- * The main task here is merging identical sets. This is usually a waste
- * of time (although the hash code minimizes the overhead), but can win
- * big if REG_ICASE is being used. REG_ICASE, by the way, is why the hash
- * is done using addition rather than xor -- all ASCII [aA] sets xor to
- * the same value!
- */
-static int /* set number */
-freezeset(p, cs)
-register struct parse *p;
-register cset *cs;
-{
- register uch h = cs->hash;
- register int i;
- register cset *top = &p->g->sets[p->g->ncsets];
- register cset *cs2;
- register size_t css = (size_t)p->g->csetsize;
-
- /* look for an earlier one which is the same */
- for (cs2 = &p->g->sets[0]; cs2 < top; cs2++)
- if (cs2->hash == h && cs2 != cs) {
- /* maybe */
- for (i = 0; i < css; i++)
- if (!!CHIN(cs2, i) != !!CHIN(cs, i))
- break; /* no */
- if (i == css)
- break; /* yes */
- }
-
- if (cs2 < top) { /* found one */
- freeset(p, cs);
- cs = cs2;
- }
-
- return((int)(cs - p->g->sets));
-}
-
-/*
- - firstch - return first character in a set (which must have at least one)
- == static int firstch(register struct parse *p, register cset *cs);
- */
-static int /* character; there is no "none" value */
-firstch(p, cs)
-register struct parse *p;
-register cset *cs;
-{
- register int i;
- register size_t css = (size_t)p->g->csetsize;
-
- for (i = 0; i < css; i++)
- if (CHIN(cs, i))
- return((char)i);
- assert(never);
- return(0); /* arbitrary */
-}
-
-/*
- - nch - number of characters in a set
- == static int nch(register struct parse *p, register cset *cs);
- */
-static int
-nch(p, cs)
-register struct parse *p;
-register cset *cs;
-{
- register int i;
- register size_t css = (size_t)p->g->csetsize;
- register int n = 0;
-
- for (i = 0; i < css; i++)
- if (CHIN(cs, i))
- n++;
- return(n);
-}
-
-/*
- - mcadd - add a collating element to a cset
- == static void mcadd(register struct parse *p, register cset *cs, \
- == register char *cp);
- */
-static void
-mcadd(p, cs, cp)
-register struct parse *p;
-register cset *cs;
-register char *cp;
-{
- register size_t oldend = cs->smultis;
-
- cs->smultis += strlen(cp) + 1;
- if (cs->multis == NULL)
- cs->multis = malloc(cs->smultis);
- else
- cs->multis = realloc(cs->multis, cs->smultis);
- if (cs->multis == NULL) {
- SETERROR(REG_ESPACE);
- return;
- }
-
- (void) strcpy(cs->multis + oldend - 1, cp);
- cs->multis[cs->smultis - 1] = '\0';
-}
-
-/*
- - mcsub - subtract a collating element from a cset
- == static void mcsub(register cset *cs, register char *cp);
- */
-static void
-mcsub(cs, cp)
-register cset *cs;
-register char *cp;
-{
- register char *fp = mcfind(cs, cp);
- register size_t len = strlen(fp);
-
- assert(fp != NULL);
- (void) memmove(fp, fp + len + 1,
- cs->smultis - (fp + len + 1 - cs->multis));
- cs->smultis -= len;
-
- if (cs->smultis == 0) {
- free(cs->multis);
- cs->multis = NULL;
- return;
- }
-
- cs->multis = realloc(cs->multis, cs->smultis);
- assert(cs->multis != NULL);
-}
-
-/*
- - mcin - is a collating element in a cset?
- == static int mcin(register cset *cs, register char *cp);
- */
-static int
-mcin(cs, cp)
-register cset *cs;
-register char *cp;
-{
- return(mcfind(cs, cp) != NULL);
-}
-
-/*
- - mcfind - find a collating element in a cset
- == static char *mcfind(register cset *cs, register char *cp);
- */
-static char *
-mcfind(cs, cp)
-register cset *cs;
-register char *cp;
-{
- register char *p;
-
- if (cs->multis == NULL)
- return(NULL);
- for (p = cs->multis; *p != '\0'; p += strlen(p) + 1)
- if (strcmp(cp, p) == 0)
- return(p);
- return(NULL);
-}
-
-/*
- - mcinvert - invert the list of collating elements in a cset
- == static void mcinvert(register struct parse *p, register cset *cs);
- *
- * This would have to know the set of possibilities. Implementation
- * is deferred.
- */
-static void
-mcinvert(p, cs)
-register struct parse *p;
-register cset *cs;
-{
- assert(cs->multis == NULL); /* xxx */
-}
-
-/*
- - mccase - add case counterparts of the list of collating elements in a cset
- == static void mccase(register struct parse *p, register cset *cs);
- *
- * This would have to know the set of possibilities. Implementation
- * is deferred.
- */
-static void
-mccase(p, cs)
-register struct parse *p;
-register cset *cs;
-{
- assert(cs->multis == NULL); /* xxx */
-}
-
-/*
- - isinsets - is this character in any sets?
- == static int isinsets(register struct re_guts *g, int c);
- */
-static int /* predicate */
-isinsets(g, c)
-register struct re_guts *g;
-int c;
-{
- register uch *col;
- register int i;
- register int ncols = (g->ncsets+(CHAR_BIT-1)) / CHAR_BIT;
- register unsigned uc = (unsigned char)c;
-
- for (i = 0, col = g->setbits; i < ncols; i++, col += g->csetsize)
- if (col[uc] != 0)
- return(1);
- return(0);
-}
-
-/*
- - samesets - are these two characters in exactly the same sets?
- == static int samesets(register struct re_guts *g, int c1, int c2);
- */
-static int /* predicate */
-samesets(g, c1, c2)
-register struct re_guts *g;
-int c1;
-int c2;
-{
- register uch *col;
- register int i;
- register int ncols = (g->ncsets+(CHAR_BIT-1)) / CHAR_BIT;
- register unsigned uc1 = (unsigned char)c1;
- register unsigned uc2 = (unsigned char)c2;
-
- for (i = 0, col = g->setbits; i < ncols; i++, col += g->csetsize)
- if (col[uc1] != col[uc2])
- return(0);
- return(1);
-}
-
-/*
- - categorize - sort out character categories
- == static void categorize(struct parse *p, register struct re_guts *g);
- */
-static void
-categorize(p, g)
-struct parse *p;
-register struct re_guts *g;
-{
- register cat_t *cats = g->categories;
- register int c;
- register int c2;
- register cat_t cat;
-
- /* avoid making error situations worse */
- if (p->error != 0)
- return;
-
- for (c = CHAR_MIN; c <= CHAR_MAX; c++)
- if (cats[c] == 0 && isinsets(g, c)) {
- cat = g->ncategories++;
- cats[c] = cat;
- for (c2 = c+1; c2 <= CHAR_MAX; c2++)
- if (cats[c2] == 0 && samesets(g, c, c2))
- cats[c2] = cat;
- }
-}
-
-/*
- - dupl - emit a duplicate of a bunch of sops
- == static sopno dupl(register struct parse *p, sopno start, sopno finish);
- */
-static sopno /* start of duplicate */
-dupl(p, start, finish)
-register struct parse *p;
-sopno start; /* from here */
-sopno finish; /* to this less one */
-{
- register sopno ret = HERE();
- register sopno len = finish - start;
-
- assert(finish >= start);
- if (len == 0)
- return(ret);
- enlarge(p, p->ssize + len); /* this many unexpected additions */
- assert(p->ssize >= p->slen + len);
- (void) memcpy((char *)(p->strip + p->slen),
- (char *)(p->strip + start), (size_t)len*sizeof(sop));
- p->slen += len;
- return(ret);
-}
-
-/*
- - doemit - emit a strip operator
- == static void doemit(register struct parse *p, sop op, size_t opnd);
- *
- * It might seem better to implement this as a macro with a function as
- * hard-case backup, but it's just too big and messy unless there are
- * some changes to the data structures. Maybe later.
- */
-static void
-doemit(p, op, opnd)
-register struct parse *p;
-sop op;
-size_t opnd;
-{
- /* avoid making error situations worse */
- if (p->error != 0)
- return;
-
- /* deal with oversize operands ("can't happen", more or less) */
- assert(opnd < 1<<OPSHIFT);
-
- /* deal with undersized strip */
- if (p->slen >= p->ssize)
- enlarge(p, (p->ssize+1) / 2 * 3); /* +50% */
- assert(p->slen < p->ssize);
-
- /* finally, it's all reduced to the easy case */
- p->strip[p->slen++] = SOP(op, opnd);
-}
-
-/*
- - doinsert - insert a sop into the strip
- == static void doinsert(register struct parse *p, sop op, size_t opnd, sopno pos);
- */
-static void
-doinsert(p, op, opnd, pos)
-register struct parse *p;
-sop op;
-size_t opnd;
-sopno pos;
-{
- register sopno sn;
- register sop s;
- register int i;
-
- /* avoid making error situations worse */
- if (p->error != 0)
- return;
-
- sn = HERE();
- EMIT(op, opnd); /* do checks, ensure space */
- assert(HERE() == sn+1);
- s = p->strip[sn];
-
- /* adjust paren pointers */
- assert(pos > 0);
- for (i = 1; i < NPAREN; i++) {
- if (p->pbegin[i] >= pos) {
- p->pbegin[i]++;
- }
- if (p->pend[i] >= pos) {
- p->pend[i]++;
- }
- }
-
- memmove((char *)&p->strip[pos+1], (char *)&p->strip[pos],
- (HERE()-pos-1)*sizeof(sop));
- p->strip[pos] = s;
-}
-
-/*
- - dofwd - complete a forward reference
- == static void dofwd(register struct parse *p, sopno pos, sop value);
- */
-static void
-dofwd(p, pos, value)
-register struct parse *p;
-register sopno pos;
-sop value;
-{
- /* avoid making error situations worse */
- if (p->error != 0)
- return;
-
- assert(value < 1<<OPSHIFT);
- p->strip[pos] = OP(p->strip[pos]) | value;
-}
-
-/*
- - enlarge - enlarge the strip
- == static void enlarge(register struct parse *p, sopno size);
- */
-static void
-enlarge(p, size)
-register struct parse *p;
-register sopno size;
-{
- register sop *sp;
-
- if (p->ssize >= size)
- return;
-
- sp = (sop *)realloc(p->strip, size*sizeof(sop));
- if (sp == NULL) {
- SETERROR(REG_ESPACE);
- return;
- }
- p->strip = sp;
- p->ssize = size;
-}
-
-/*
- - stripsnug - compact the strip
- == static void stripsnug(register struct parse *p, register struct re_guts *g);
- */
-static void
-stripsnug(p, g)
-register struct parse *p;
-register struct re_guts *g;
-{
- g->nstates = p->slen;
- g->strip = (sop *)realloc((char *)p->strip, p->slen * sizeof(sop));
- if (g->strip == NULL) {
- SETERROR(REG_ESPACE);
- g->strip = p->strip;
- }
-}
-
-/*
- - findmust - fill in must and mlen with longest mandatory literal string
- == static void findmust(register struct parse *p, register struct re_guts *g);
- *
- * This algorithm could do fancy things like analyzing the operands of |
- * for common subsequences. Someday. This code is simple and finds most
- * of the interesting cases.
- *
- * Note that must and mlen got initialized during setup.
- */
-static void
-findmust(p, g)
-struct parse *p;
-register struct re_guts *g;
-{
- register sop *scan;
- sop *start;
- register sop *newstart;
- register sopno newlen;
- register sop s;
- register char *cp;
- register sopno i;
-
- /* avoid making error situations worse */
- if (p->error != 0)
- return;
-
- /* find the longest OCHAR sequence in strip */
- newlen = 0;
- scan = g->strip + 1;
- do {
- s = *scan++;
- switch (OP(s)) {
- case OCHAR: /* sequence member */
- if (newlen == 0) /* new sequence */
- newstart = scan - 1;
- newlen++;
- break;
- case OPLUS_: /* things that don't break one */
- case OLPAREN:
- case ORPAREN:
- break;
- case OQUEST_: /* things that must be skipped */
- case OCH_:
- scan--;
- do {
- scan += OPND(s);
- s = *scan;
- /* assert() interferes w debug printouts */
- if (OP(s) != O_QUEST && OP(s) != O_CH &&
- OP(s) != OOR2) {
- g->iflags |= BAD;
- return;
- }
- } while (OP(s) != O_QUEST && OP(s) != O_CH);
- /* fallthrough */
- default: /* things that break a sequence */
- if (newlen > g->mlen) { /* ends one */
- start = newstart;
- g->mlen = newlen;
- }
- newlen = 0;
- break;
- }
- } while (OP(s) != OEND);
-
- if (g->mlen == 0) /* there isn't one */
- return;
-
- /* turn it into a character string */
- g->must = malloc((size_t)g->mlen + 1);
- if (g->must == NULL) { /* argh; just forget it */
- g->mlen = 0;
- return;
- }
- cp = g->must;
- scan = start;
- for (i = g->mlen; i > 0; i--) {
- while (OP(s = *scan++) != OCHAR)
- continue;
- assert(cp < g->must + g->mlen);
- *cp++ = (char)OPND(s);
- }
- assert(cp == g->must + g->mlen);
- *cp++ = '\0'; /* just on general principles */
-}
-
-/*
- - pluscount - count + nesting
- == static sopno pluscount(register struct parse *p, register struct re_guts *g);
- */
-static sopno /* nesting depth */
-pluscount(p, g)
-struct parse *p;
-register struct re_guts *g;
-{
- register sop *scan;
- register sop s;
- register sopno plusnest = 0;
- register sopno maxnest = 0;
-
- if (p->error != 0)
- return(0); /* there may not be an OEND */
-
- scan = g->strip + 1;
- do {
- s = *scan++;
- switch (OP(s)) {
- case OPLUS_:
- plusnest++;
- break;
- case O_PLUS:
- if (plusnest > maxnest)
- maxnest = plusnest;
- plusnest--;
- break;
- }
- } while (OP(s) != OEND);
- if (plusnest != 0)
- g->iflags |= BAD;
- return(maxnest);
-}