1 /*	$NetBSD: regexec.c,v 1.22 2012/03/13 21:13:43 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1992, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Henry Spencer.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	@(#)regexec.c	8.3 (Berkeley) 3/20/94
35  */
36 
37 /*-
38  * Copyright (c) 1992, 1993, 1994 Henry Spencer.
39  *
40  * This code is derived from software contributed to Berkeley by
41  * Henry Spencer.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. All advertising materials mentioning features or use of this software
52  *    must display the following acknowledgement:
53  *	This product includes software developed by the University of
54  *	California, Berkeley and its contributors.
55  * 4. Neither the name of the University nor the names of its contributors
56  *    may be used to endorse or promote products derived from this software
57  *    without specific prior written permission.
58  *
59  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69  * SUCH DAMAGE.
70  *
71  *	@(#)regexec.c	8.3 (Berkeley) 3/20/94
72  */
73 
74 #include <sys/cdefs.h>
75 #if defined(LIBC_SCCS) && !defined(lint)
76 #if 0
77 static char sccsid[] = "@(#)regexec.c	8.3 (Berkeley) 3/20/94";
78 #else
79 __RCSID("$NetBSD: regexec.c,v 1.22 2012/03/13 21:13:43 christos Exp $");
80 #endif
81 #endif /* LIBC_SCCS and not lint */
82 
83 /*
84  * the outer shell of regexec()
85  *
86  * This file includes engine.c *twice*, after muchos fiddling with the
87  * macros that code uses.  This lets the same code operate on two different
88  * representations for state sets.
89  */
90 #include "namespace.h"
91 #include <sys/types.h>
92 
93 #include <assert.h>
94 #include <ctype.h>
95 #include <limits.h>
96 #include <stdio.h>
97 #include <stdlib.h>
98 #include <string.h>
99 #include <regex.h>
100 
101 #ifdef __weak_alias
__weak_alias(regexec,_regexec)102 __weak_alias(regexec,_regexec)
103 #endif
104 
105 #include "utils.h"
106 #include "regex2.h"
107 
108 /* macros for manipulating states, small version */
109 #define	states	unsigned long
110 #define	states1	unsigned long	/* for later use in regexec() decision */
111 #define	CLEAR(v)	((v) = 0)
112 #define	SET0(v, n)	((v) &= ~((unsigned long)1 << (n)))
113 #define	SET1(v, n)	((v) |= (unsigned long)1 << (n))
114 #define	ISSET(v, n)	(((v) & ((unsigned long)1 << (n))) != 0)
115 #define	ASSIGN(d, s)	((d) = (s))
116 #define	EQ(a, b)	((a) == (b))
117 #define	STATEVARS	int dummy	/* dummy version */
118 #define	STATESETUP(m, n)	/* nothing */
119 #define	STATETEARDOWN(m)	/* nothing */
120 #define	SETUP(v)	((v) = 0)
121 #define	onestate	unsigned long
122 #define	INIT(o, n)	((o) = (unsigned long)1 << (n))
123 #define	INC(o)	((o) <<= 1)
124 #define	ISSTATEIN(v, o)	(((v) & (o)) != 0)
125 /* some abbreviations; note that some of these know variable names! */
126 /* do "if I'm here, I can also be there" etc without branches */
127 #define	FWD(dst, src, n)	((dst) |= ((unsigned long)(src)&(here)) << (n))
128 #define	BACK(dst, src, n)	((dst) |= ((unsigned long)(src)&(here)) >> (n))
129 #define	ISSETBACK(v, n)	(((v) & ((unsigned long)here >> (n))) != 0)
130 /* function names */
131 #define SNAMES			/* engine.c looks after details */
132 
133 #include "engine.c"
134 
135 /* now undo things */
136 #undef	states
137 #undef	CLEAR
138 #undef	SET0
139 #undef	SET1
140 #undef	ISSET
141 #undef	ASSIGN
142 #undef	EQ
143 #undef	STATEVARS
144 #undef	STATESETUP
145 #undef	STATETEARDOWN
146 #undef	SETUP
147 #undef	onestate
148 #undef	INIT
149 #undef	INC
150 #undef	ISSTATEIN
151 #undef	FWD
152 #undef	BACK
153 #undef	ISSETBACK
154 #undef	SNAMES
155 
156 /* macros for manipulating states, large version */
157 #define	states	char *
158 #define	CLEAR(v)	memset(v, 0, (size_t)m->g->nstates)
159 #define	SET0(v, n)	((v)[n] = 0)
160 #define	SET1(v, n)	((v)[n] = 1)
161 #define	ISSET(v, n)	((v)[n])
162 #define	ASSIGN(d, s)	memcpy(d, s, (size_t)m->g->nstates)
163 #define	EQ(a, b)	(memcmp(a, b, (size_t)m->g->nstates) == 0)
164 #define	STATEVARS	int vn; char *space
165 #define	STATESETUP(m, nv) \
166     if (((m)->space = malloc((size_t)((nv)*(m)->g->nstates))) == NULL) \
167 	return(REG_ESPACE); \
168     else \
169 	(m)->vn = 0
170 
171 #define	STATETEARDOWN(m)	{ free((m)->space); m->space = NULL; }
172 #define	SETUP(v)	((v) = &m->space[(size_t)(m->vn++ * m->g->nstates)])
173 #define	onestate	int
174 #define	INIT(o, n)	((o) = (int)(n))
175 #define	INC(o)	((o)++)
176 #define	ISSTATEIN(v, o)	((v)[o])
177 /* some abbreviations; note that some of these know variable names! */
178 /* do "if I'm here, I can also be there" etc without branches */
179 #define	FWD(dst, src, n)	((dst)[here+(n)] |= (src)[here])
180 #define	BACK(dst, src, n)	((dst)[here-(n)] |= (src)[here])
181 #define	ISSETBACK(v, n)	((v)[here - (n)])
182 /* function names */
183 #define	LNAMES			/* flag */
184 
185 #include "engine.c"
186 
187 /*
188  - regexec - interface for matching
189  = extern int regexec(const regex_t *, const char *, size_t, \
190  =					regmatch_t [], int);
191  = #define	REG_NOTBOL	00001
192  = #define	REG_NOTEOL	00002
193  = #define	REG_STARTEND	00004
194  = #define	REG_TRACE	00400	// tracing of execution
195  = #define	REG_LARGE	01000	// force large representation
196  = #define	REG_BACKR	02000	// force use of backref code
197  *
198  * We put this here so we can exploit knowledge of the state representation
199  * when choosing which matcher to call.  Also, by this point the matchers
200  * have been prototyped.
201  */
202 int				/* 0 success, REG_NOMATCH failure */
203 regexec(
204     const regex_t *preg,
205     const char *string,
206     size_t nmatch,
207     regmatch_t pmatch[],
208     int eflags)
209 {
210 	struct re_guts *g = preg->re_g;
211 	char *s;
212 #ifdef REDEBUG
213 #	define	GOODFLAGS(f)	(f)
214 #else
215 #	define	GOODFLAGS(f)	((f)&(REG_NOTBOL|REG_NOTEOL|REG_STARTEND))
216 #endif
217 
218 	_DIAGASSERT(preg != NULL);
219 	_DIAGASSERT(string != NULL);
220 
221 	if (preg->re_magic != MAGIC1 || g->magic != MAGIC2)
222 		return(REG_BADPAT);
223 	assert(!(g->iflags&BAD));
224 	if (g->iflags&BAD)		/* backstop for no-debug case */
225 		return(REG_BADPAT);
226 	eflags = GOODFLAGS(eflags);
227 
228 	s = __UNCONST(string);
229 
230 	if (g->nstates <= (sopno)(CHAR_BIT*sizeof(states1)) && !(eflags&REG_LARGE))
231 		return(smatcher(g, s, nmatch, pmatch, eflags));
232 	else
233 		return(lmatcher(g, s, nmatch, pmatch, eflags));
234 }
235