minix/lib/libc/regex/regcomp.c
Ben Gras 2fe8fb192f Full switch to clang/ELF. Drop ack. Simplify.
There is important information about booting non-ack images in
docs/UPDATING. ack/aout-format images can't be built any more, and
booting clang/ELF-format ones is a little different. Updating to the
new boot monitor is recommended.

Changes in this commit:

	. drop boot monitor -> allowing dropping ack support
	. facility to copy ELF boot files to /boot so that old boot monitor
	  can still boot fairly easily, see UPDATING
	. no more ack-format libraries -> single-case libraries
	. some cleanup of OBJECT_FMT, COMPILER_TYPE, etc cases
	. drop several ack toolchain commands, but not all support
	  commands (e.g. aal is gone but acksize is not yet).
	. a few libc files moved to netbsd libc dir
	. new /bin/date as minix date used code in libc/
	. test compile fix
	. harmonize includes
	. /usr/lib is no longer special: without ack, /usr/lib plays no
	  kind of special bootstrapping role any more and bootstrapping
	  is done exclusively through packages, so releases depend even
	  less on the state of the machine making them now.
	. rename nbsd_lib* to lib*
	. reduce mtree
2012-02-14 14:52:02 +01:00

1902 lines
42 KiB
C

/* $NetBSD: regcomp.c,v 1.29 2009/02/12 05:06:54 lukem Exp $ */
/*-
* 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. 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.
*
* @(#)regcomp.c 8.5 (Berkeley) 3/20/94
*/
/*-
* Copyright (c) 1992, 1993, 1994 Henry Spencer.
*
* 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.
*
* @(#)regcomp.c 8.5 (Berkeley) 3/20/94
*/
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)regcomp.c 8.5 (Berkeley) 3/20/94";
#else
__RCSID("$NetBSD: regcomp.c,v 1.29 2009/02/12 05:06:54 lukem Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
#include "namespace.h"
#include <sys/types.h>
#include <assert.h>
#include <ctype.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <regex.h>
#ifdef __weak_alias
__weak_alias(regcomp,_regcomp)
#endif
#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 {
const char *next; /* next character in RE */
const 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(struct parse *p, int stop);
static void p_ere_exp(struct parse *p);
static void p_str(struct parse *p);
static void p_bre(struct parse *p, int end1, int end2);
static int p_simp_re(struct parse *p, int starordinary);
static int p_count(struct parse *p);
static void p_bracket(struct parse *p);
static void p_b_term(struct parse *p, cset *cs);
static void p_b_cclass(struct parse *p, cset *cs);
static void p_b_eclass(struct parse *p, cset *cs);
static char p_b_symbol(struct parse *p);
static char p_b_coll_elem(struct parse *p, int endc);
static int othercase(int ch);
static void bothcases(struct parse *p, int ch);
static void ordinary(struct parse *p, int ch);
static void nonnewline(struct parse *p);
static void repeat(struct parse *p, sopno start, int from, int to);
static int seterr(struct parse *p, int e);
static cset *allocset(struct parse *p);
static void freeset(struct parse *p, cset *cs);
static int freezeset(struct parse *p, cset *cs);
static int firstch(struct parse *p, cset *cs);
static int nch(struct parse *p, cset *cs);
static void mcadd(struct parse *p, cset *cs, const char *cp);
#if 0
static void mcsub(cset *cs, char *cp);
static int mcin(cset *cs, char *cp);
static char *mcfind(cset *cs, char *cp);
#endif
static void mcinvert(struct parse *p, cset *cs);
static void mccase(struct parse *p, cset *cs);
static int isinsets(struct re_guts *g, int c);
static int samesets(struct re_guts *g, int c1, int c2);
static void categorize(struct parse *p, struct re_guts *g);
static sopno dupl(struct parse *p, sopno start, sopno finish);
static void doemit(struct parse *p, sop op, sopno opnd);
static void doinsert(struct parse *p, sop op, sopno opnd, sopno pos);
static void dofwd(struct parse *p, sopno pos, sopno value);
static void enlarge(struct parse *p, sopno size);
static void stripsnug(struct parse *p, struct re_guts *g);
static void findmust(struct parse *p, struct re_guts *g);
static sopno pluscount(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) (void) ((co) || SETERROR(e))
#define MUSTSEE(c, e) (REQUIRE(MORE() && PEEK() == (c), e))
#define MUSTEAT(c, e) (void) (REQUIRE(MORE() && GETNEXT() == (c), e))
#define MUSTNOTSEE(c, e) (REQUIRE(!MORE() || PEEK() != (c), e))
#define EMIT(op, sopnd) doemit(p, (sop)(op), 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(
regex_t *preg,
const char *pattern,
int cflags)
{
struct parse pa;
struct re_guts *g;
struct parse *p = &pa;
int i;
size_t len;
#ifdef REDEBUG
# define GOODFLAGS(f) (f)
#else
# define GOODFLAGS(f) ((f)&~REG_DUMP)
#endif
_DIAGASSERT(preg != NULL);
_DIAGASSERT(pattern != NULL);
cflags = GOODFLAGS(cflags);
if ((cflags&REG_EXTENDED) && (cflags&REG_NOSPEC))
return(REG_INVARG);
if (cflags&REG_PEND) {
if (preg->re_endp < pattern)
return(REG_INVARG);
len = preg->re_endp - pattern;
} else
len = strlen(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(g);
return(REG_ESPACE);
}
/* set things up */
p->g = g;
p->next = pattern;
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&REG_EXTENDED)
p_ere(p, OUT);
else if (cflags&REG_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(struct parse *p, int stop);
*/
static void
p_ere(
struct parse *p,
int stop) /* character this ERE should end at */
{
char c;
sopno prevback = 0; /* pacify gcc */
sopno prevfwd = 0; /* pacify gcc */
sopno conc;
int first = 1; /* is this the first alternative? */
_DIAGASSERT(p != NULL);
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(struct parse *p);
*/
static void
p_ere_exp(
struct parse *p)
{
char c;
sopno pos;
int count;
int count2;
sopno subno;
int wascaret = 0;
_DIAGASSERT(p != NULL);
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&REG_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((unsigned char)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((unsigned char)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((unsigned char)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((unsigned char)PEEK2())) ) )
return;
SETERROR(REG_BADRPT);
}
/*
- p_str - string (no metacharacters) "parser"
== static void p_str(struct parse *p);
*/
static void
p_str(
struct parse *p)
{
_DIAGASSERT(p != NULL);
REQUIRE(MORE(), REG_EMPTY);
while (MORE())
ordinary(p, GETNEXT());
}
/*
- p_bre - BRE parser top level, anchoring and concatenation
== static void p_bre(struct parse *p, int end1, \
== 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(
struct parse *p,
int end1, /* first terminating character */
int end2) /* second terminating character */
{
sopno start;
int first = 1; /* first subexpression? */
int wasdollar = 0;
_DIAGASSERT(p != NULL);
start = HERE();
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(struct parse *p, int starordinary);
*/
static int /* was the simple RE an unbackslashed $? */
p_simp_re(
struct parse *p,
int starordinary) /* is a leading * an ordinary character? */
{
int c;
int count;
int count2;
sopno pos;
int i;
sopno subno;
# define BACKSL (1<<CHAR_BIT)
_DIAGASSERT(p != NULL);
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&REG_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((unsigned char)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(struct parse *p);
*/
static int /* the value */
p_count(
struct parse *p)
{
int count = 0;
int ndigits = 0;
_DIAGASSERT(p != NULL);
while (MORE() && isdigit((unsigned char)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(struct parse *p);
*
* Note a significant property of this code: if the allocset() did SETERROR,
* no set operations are done.
*/
static void
p_bracket(
struct parse *p)
{
cset *cs;
int invert = 0;
_DIAGASSERT(p != NULL);
cs = allocset(p);
/* Dept of Truly Sickening Special-Case Kludges */
if (p->next + 5 < p->end && strncmp(p->next, "[:<:]]",
(size_t)6) == 0) {
EMIT(OBOW, 0);
NEXTn(6);
return;
}
if (p->next + 5 < p->end && strncmp(p->next, "[:>:]]",
(size_t)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&REG_ICASE) {
int i;
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) {
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&REG_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(struct parse *p, cset *cs);
*/
static void
p_b_term(
struct parse *p,
cset *cs)
{
char c;
char start, finish;
int i;
_DIAGASSERT(p != NULL);
_DIAGASSERT(cs != NULL);
/* classify what we've got */
switch ((MORE()) ? PEEK() : '\0') {
case '[':
c = (MORE2()) ? PEEK2() : '\0';
break;
case '-':
SETERROR(REG_ERANGE);
return; /* NOTE RETURN */
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(struct parse *p, cset *cs);
*/
static void
p_b_cclass(
struct parse *p,
cset *cs)
{
const char *sp;
const struct cclass *cp;
size_t len;
const char *u;
char c;
_DIAGASSERT(p != NULL);
_DIAGASSERT(cs != NULL);
sp = p->next;
while (MORE() && isalpha((unsigned char)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(struct parse *p, cset *cs);
*
* This implementation is incomplete. xxx
*/
static void
p_b_eclass(
struct parse *p,
cset *cs)
{
char c;
_DIAGASSERT(p != NULL);
_DIAGASSERT(cs != NULL);
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(struct parse *p);
*/
static char /* value of symbol */
p_b_symbol(
struct parse *p)
{
char value;
_DIAGASSERT(p != NULL);
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(struct parse *p, int endc);
*/
static char /* value of collating element */
p_b_coll_elem(
struct parse *p,
int endc) /* name ended by endc,']' */
{
const char *sp;
const struct cname *cp;
size_t len;
_DIAGASSERT(p != NULL);
sp = p->next;
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 int othercase(int ch);
*/
static int /* if no counterpart, return ch */
othercase(
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(struct parse *p, int ch);
*
* Boy, is this implementation ever a kludge...
*/
static void
bothcases(
struct parse *p,
int ch)
{
const char *oldnext;
const char *oldend;
char bracket[3];
_DIAGASSERT(p != NULL);
oldnext = p->next;
oldend = p->end;
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(struct parse *p, int ch);
*/
static void
ordinary(
struct parse *p,
int ch)
{
cat_t *cap;
_DIAGASSERT(p != NULL);
cap = p->g->categories;
if ((p->g->cflags&REG_ICASE) && isalpha((unsigned char) ch)
&& othercase((unsigned char) ch) != (unsigned char) ch)
bothcases(p, (unsigned char) 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(struct parse *p);
*
* Boy, is this implementation ever a kludge...
*/
static void
nonnewline(
struct parse *p)
{
const char *oldnext;
const char *oldend;
char bracket[4];
_DIAGASSERT(p != NULL);
oldnext = p->next;
oldend = p->end;
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(struct parse *p, sopno start, int from, int to);
*/
static void
repeat(
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) */
{
sopno finish;
# define N 2
# define INF 3
# define REP(f, t) ((f)*8 + (t))
# define MAP(n) (((n) <= 1) ? (n) : ((n) == INFINITY) ? INF : N)
sopno copy;
_DIAGASSERT(p != NULL);
finish = HERE();
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(struct parse *p, int e);
*/
static int /* useless but makes type checking happy */
seterr(
struct parse *p,
int e)
{
_DIAGASSERT(p != NULL);
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(struct parse *p);
*/
static cset *
allocset(
struct parse *p)
{
int no;
size_t nc;
size_t nbytes;
cset *cs;
size_t css;
int i;
_DIAGASSERT(p != NULL);
no = p->g->ncsets++;
css = (size_t)p->g->csetsize;
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 = malloc(nc * sizeof(cset));
else
p->g->sets = realloc(p->g->sets, nc * sizeof(cset));
if (p->g->setbits == NULL)
p->g->setbits = malloc(nbytes);
else {
p->g->setbits = realloc(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(struct parse *p, cset *cs);
*/
static void
freeset(
struct parse *p,
cset *cs)
{
size_t i;
cset *top;
size_t css;
_DIAGASSERT(p != NULL);
_DIAGASSERT(cs != NULL);
top = &p->g->sets[p->g->ncsets];
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(struct parse *p, 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(
struct parse *p,
cset *cs)
{
uch h;
size_t i;
cset *top;
cset *cs2;
size_t css;
_DIAGASSERT(p != NULL);
_DIAGASSERT(cs != NULL);
h = cs->hash;
top = &p->g->sets[p->g->ncsets];
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(struct parse *p, cset *cs);
*/
static int /* character; there is no "none" value */
firstch(
struct parse *p,
cset *cs)
{
size_t i;
size_t css;
_DIAGASSERT(p != NULL);
_DIAGASSERT(cs != NULL);
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(struct parse *p, cset *cs);
*/
static int
nch(
struct parse *p,
cset *cs)
{
size_t i;
size_t css;
int n = 0;
_DIAGASSERT(p != NULL);
_DIAGASSERT(cs != NULL);
css = (size_t)p->g->csetsize;
for (i = 0; i < css; i++)
if (CHIN(cs, i))
n++;
return(n);
}
/*
- mcadd - add a collating element to a cset
== static void mcadd(struct parse *p, cset *cs, \
== char *cp);
*/
static void
mcadd(
struct parse *p,
cset *cs,
const char *cp)
{
size_t oldend;
_DIAGASSERT(p != NULL);
_DIAGASSERT(cs != NULL);
_DIAGASSERT(cp != NULL);
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';
}
#if 0
/*
- mcsub - subtract a collating element from a cset
== static void mcsub(cset *cs, char *cp);
*/
static void
mcsub(
cset *cs,
char *cp)
{
char *fp;
size_t len;
_DIAGASSERT(cs != NULL);
_DIAGASSERT(cp != NULL);
fp = mcfind(cs, cp);
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(cset *cs, char *cp);
*/
static int
mcin(
cset *cs,
char *cp)
{
_DIAGASSERT(cs != NULL);
_DIAGASSERT(cp != NULL);
return(mcfind(cs, cp) != NULL);
}
/*
- mcfind - find a collating element in a cset
== static char *mcfind(cset *cs, char *cp);
*/
static char *
mcfind(
cset *cs,
char *cp)
{
char *p;
_DIAGASSERT(cs != NULL);
_DIAGASSERT(cp != NULL);
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);
}
#endif
/*
- mcinvert - invert the list of collating elements in a cset
== static void mcinvert(struct parse *p, cset *cs);
*
* This would have to know the set of possibilities. Implementation
* is deferred.
*/
/* ARGSUSED */
static void
mcinvert(
struct parse *p,
cset *cs)
{
_DIAGASSERT(p != NULL);
_DIAGASSERT(cs != NULL);
assert(cs->multis == NULL); /* xxx */
}
/*
- mccase - add case counterparts of the list of collating elements in a cset
== static void mccase(struct parse *p, cset *cs);
*
* This would have to know the set of possibilities. Implementation
* is deferred.
*/
/* ARGSUSED */
static void
mccase(
struct parse *p,
cset *cs)
{
_DIAGASSERT(p != NULL);
_DIAGASSERT(cs != NULL);
assert(cs->multis == NULL); /* xxx */
}
/*
- isinsets - is this character in any sets?
== static int isinsets(struct re_guts *g, int c);
*/
static int /* predicate */
isinsets(
struct re_guts *g,
int c)
{
uch *col;
int i;
int ncols;
unsigned uc = (unsigned char)c;
_DIAGASSERT(g != NULL);
ncols = (g->ncsets+(CHAR_BIT-1)) / CHAR_BIT;
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(struct re_guts *g, int c1, int c2);
*/
static int /* predicate */
samesets(
struct re_guts *g,
int c1,
int c2)
{
uch *col;
int i;
int ncols;
unsigned uc1 = (unsigned char)c1;
unsigned uc2 = (unsigned char)c2;
_DIAGASSERT(g != NULL);
ncols = (g->ncsets+(CHAR_BIT-1)) / CHAR_BIT;
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, struct re_guts *g);
*/
static void
categorize(
struct parse *p,
struct re_guts *g)
{
cat_t *cats;
int c;
int c2;
cat_t cat;
_DIAGASSERT(p != NULL);
_DIAGASSERT(g != NULL);
cats = g->categories;
/* 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(struct parse *p, sopno start, sopno finish);
*/
static sopno /* start of duplicate */
dupl(
struct parse *p,
sopno start, /* from here */
sopno finish) /* to this less one */
{
sopno ret;
sopno len = finish - start;
_DIAGASSERT(p != NULL);
ret = HERE();
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(p->strip + p->slen, p->strip + start,
(size_t)len * sizeof(sop));
p->slen += len;
return(ret);
}
/*
- doemit - emit a strip operator
== static void doemit(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(
struct parse *p,
sop op,
sopno opnd)
{
_DIAGASSERT(p != NULL);
/* 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(struct parse *p, sop op, size_t opnd, sopno pos);
*/
static void
doinsert(
struct parse *p,
sop op,
sopno opnd,
sopno pos)
{
sopno sn;
sop s;
int i;
_DIAGASSERT(p != NULL);
/* 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(&p->strip[pos+1], &p->strip[pos], (HERE()-pos-1)*sizeof(sop));
p->strip[pos] = s;
}
/*
- dofwd - complete a forward reference
== static void dofwd(struct parse *p, sopno pos, sop value);
*/
static void
dofwd(
struct parse *p,
sopno pos,
sopno value)
{
_DIAGASSERT(p != NULL);
/* 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(struct parse *p, sopno size);
*/
static void
enlarge(
struct parse *p,
sopno size)
{
sop *sp;
_DIAGASSERT(p != NULL);
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(struct parse *p, struct re_guts *g);
*/
static void
stripsnug(
struct parse *p,
struct re_guts *g)
{
_DIAGASSERT(p != NULL);
_DIAGASSERT(g != NULL);
g->nstates = p->slen;
g->strip = realloc(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(struct parse *p, 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(
struct parse *p,
struct re_guts *g)
{
sop *scan;
sop *start = NULL;
sop *newstart = NULL;
sopno newlen;
sop s;
char *cp;
sopno i;
_DIAGASSERT(p != NULL);
_DIAGASSERT(g != NULL);
/* 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 (start == NULL)
g->mlen = 0;
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(struct parse *p, struct re_guts *g);
*/
static sopno /* nesting depth */
pluscount(
struct parse *p,
struct re_guts *g)
{
sop *scan;
sop s;
sopno plusnest = 0;
sopno maxnest = 0;
_DIAGASSERT(p != NULL);
_DIAGASSERT(g != NULL);
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);
}