summaryrefslogtreecommitdiff
path: root/lib/libc/regex/regexec.c
blob: c644b4ff41bda9ed2524497c1ad4b15b64282401 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
/*-
 * Copyright (c) 1992, 1993, 1994 Henry Spencer.
 * 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.
 *
 *	@(#)regexec.c	8.3 (Berkeley) 3/20/94
 */

#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)regexec.c	8.3 (Berkeley) 3/20/94";
#else
static char rcsid[] = "$OpenBSD: regexec.c,v 1.10 2004/11/30 17:04:23 otto Exp $";
#endif
#endif /* LIBC_SCCS and not lint */

/*
 * the outer shell of regexec()
 *
 * This file includes engine.c *twice*, after muchos fiddling with the
 * macros that code uses.  This lets the same code operate on two different
 * representations for state sets.
 */
#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <ctype.h>
#include <regex.h>

#include "utils.h"
#include "regex2.h"

/* macros for manipulating states, small version */
#define	states	long
#define	states1	states		/* for later use in regexec() decision */
#define	CLEAR(v)	((v) = 0)
#define	SET0(v, n)	((v) &= ~((unsigned long)1 << (n)))
#define	SET1(v, n)	((v) |= (unsigned long)1 << (n))
#define	ISSET(v, n)	(((v) & ((unsigned long)1 << (n))) != 0)
#define	ASSIGN(d, s)	((d) = (s))
#define	EQ(a, b)	((a) == (b))
#define	STATEVARS	long dummy	/* dummy version */
#define	STATESETUP(m, n)	/* nothing */
#define	STATETEARDOWN(m)	/* nothing */
#define	SETUP(v)	((v) = 0)
#define	onestate	long
#define	INIT(o, n)	((o) = (unsigned long)1 << (n))
#define	INC(o)		((o) <<= 1)
#define	ISSTATEIN(v, o)	(((v) & (o)) != 0)
/* some abbreviations; note that some of these know variable names! */
/* do "if I'm here, I can also be there" etc without branches */
#define	FWD(dst, src, n)	((dst) |= ((unsigned long)(src)&(here)) << (n))
#define	BACK(dst, src, n)	((dst) |= ((unsigned long)(src)&(here)) >> (n))
#define	ISSETBACK(v, n)		(((v) & ((unsigned long)here >> (n))) != 0)
/* function names */
#define SNAMES			/* engine.c looks after details */

#include "engine.c"

/* now undo things */
#undef	states
#undef	CLEAR
#undef	SET0
#undef	SET1
#undef	ISSET
#undef	ASSIGN
#undef	EQ
#undef	STATEVARS
#undef	STATESETUP
#undef	STATETEARDOWN
#undef	SETUP
#undef	onestate
#undef	INIT
#undef	INC
#undef	ISSTATEIN
#undef	FWD
#undef	BACK
#undef	ISSETBACK
#undef	SNAMES

/* macros for manipulating states, large version */
#define	states	char *
#define	CLEAR(v)	memset(v, 0, m->g->nstates)
#define	SET0(v, n)	((v)[n] = 0)
#define	SET1(v, n)	((v)[n] = 1)
#define	ISSET(v, n)	((v)[n])
#define	ASSIGN(d, s)	memcpy(d, s, m->g->nstates)
#define	EQ(a, b)	(memcmp(a, b, m->g->nstates) == 0)
#define	STATEVARS	long vn; char *space
#define	STATESETUP(m, nv)	{ (m)->space = malloc((nv)*(m)->g->nstates); \
				if ((m)->space == NULL) return(REG_ESPACE); \
				(m)->vn = 0; }
#define	STATETEARDOWN(m)	{ free((m)->space); }
#define	SETUP(v)	((v) = &m->space[m->vn++ * m->g->nstates])
#define	onestate	long
#define	INIT(o, n)	((o) = (n))
#define	INC(o)	((o)++)
#define	ISSTATEIN(v, o)	((v)[o])
/* some abbreviations; note that some of these know variable names! */
/* do "if I'm here, I can also be there" etc without branches */
#define	FWD(dst, src, n)	((dst)[here+(n)] |= (src)[here])
#define	BACK(dst, src, n)	((dst)[here-(n)] |= (src)[here])
#define	ISSETBACK(v, n)	((v)[here - (n)])
/* function names */
#define	LNAMES			/* flag */

#include "engine.c"

/*
 - regexec - interface for matching
 *
 * We put this here so we can exploit knowledge of the state representation
 * when choosing which matcher to call.  Also, by this point the matchers
 * have been prototyped.
 */
int				/* 0 success, REG_NOMATCH failure */
regexec(const regex_t *preg, const char *string, size_t nmatch,
    regmatch_t pmatch[], int eflags)
{
	struct re_guts *g = preg->re_g;
#ifdef REDEBUG
#	define	GOODFLAGS(f)	(f)
#else
#	define	GOODFLAGS(f)	((f)&(REG_NOTBOL|REG_NOTEOL|REG_STARTEND))
#endif

	if (preg->re_magic != MAGIC1 || g->magic != MAGIC2)
		return(REG_BADPAT);
	assert(!(g->iflags&BAD));
	if (g->iflags&BAD)		/* backstop for no-debug case */
		return(REG_BADPAT);
	eflags = GOODFLAGS(eflags);

	if (g->nstates <= CHAR_BIT*sizeof(states1) && !(eflags&REG_LARGE))
		return(smatcher(g, (char *)string, nmatch, pmatch, eflags));
	else
		return(lmatcher(g, (char *)string, nmatch, pmatch, eflags));
}