regexec.c revision 1.15 1 /* $NetBSD: regexec.c,v 1.15 2000/01/22 22:19:17 mycroft Exp $ */
2
3 /*-
4 * Copyright (c) 1992, 1993, 1994 Henry Spencer.
5 * Copyright (c) 1992, 1993, 1994
6 * The Regents of the University of California. All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Henry Spencer.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the University of
22 * California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 * @(#)regexec.c 8.3 (Berkeley) 3/20/94
40 */
41
42 #include <sys/cdefs.h>
43 #if defined(LIBC_SCCS) && !defined(lint)
44 #if 0
45 static char sccsid[] = "@(#)regexec.c 8.3 (Berkeley) 3/20/94";
46 #else
47 __RCSID("$NetBSD: regexec.c,v 1.15 2000/01/22 22:19:17 mycroft Exp $");
48 #endif
49 #endif /* LIBC_SCCS and not lint */
50
51 /*
52 * the outer shell of regexec()
53 *
54 * This file includes engine.c *twice*, after muchos fiddling with the
55 * macros that code uses. This lets the same code operate on two different
56 * representations for state sets.
57 */
58 #include "namespace.h"
59 #include <sys/types.h>
60
61 #include <assert.h>
62 #include <ctype.h>
63 #include <limits.h>
64 #include <regex.h>
65 #include <stdio.h>
66 #include <stdlib.h>
67 #include <string.h>
68
69 #ifdef __weak_alias
70 __weak_alias(regexec,_regexec)
71 #endif
72
73 #include "utils.h"
74 #include "regex2.h"
75
76 /* macros for manipulating states, small version */
77 #define states unsigned long
78 #define states1 unsigned long /* for later use in regexec() decision */
79 #define CLEAR(v) ((v) = 0)
80 #define SET0(v, n) ((v) &= ~((unsigned long)1 << (n)))
81 #define SET1(v, n) ((v) |= (unsigned long)1 << (n))
82 #define ISSET(v, n) (((v) & ((unsigned long)1 << (n))) != 0)
83 #define ASSIGN(d, s) ((d) = (s))
84 #define EQ(a, b) ((a) == (b))
85 #define STATEVARS int dummy /* dummy version */
86 #define STATESETUP(m, n) /* nothing */
87 #define STATETEARDOWN(m) /* nothing */
88 #define SETUP(v) ((v) = 0)
89 #define onestate unsigned long
90 #define INIT(o, n) ((o) = (unsigned long)1 << (n))
91 #define INC(o) ((o) <<= 1)
92 #define ISSTATEIN(v, o) (((v) & (o)) != 0)
93 /* some abbreviations; note that some of these know variable names! */
94 /* do "if I'm here, I can also be there" etc without branches */
95 #define FWD(dst, src, n) ((dst) |= ((unsigned long)(src)&(here)) << (n))
96 #define BACK(dst, src, n) ((dst) |= ((unsigned long)(src)&(here)) >> (n))
97 #define ISSETBACK(v, n) (((v) & ((unsigned long)here >> (n))) != 0)
98 /* function names */
99 #define SNAMES /* engine.c looks after details */
100
101 #include "engine.c"
102
103 /* now undo things */
104 #undef states
105 #undef CLEAR
106 #undef SET0
107 #undef SET1
108 #undef ISSET
109 #undef ASSIGN
110 #undef EQ
111 #undef STATEVARS
112 #undef STATESETUP
113 #undef STATETEARDOWN
114 #undef SETUP
115 #undef onestate
116 #undef INIT
117 #undef INC
118 #undef ISSTATEIN
119 #undef FWD
120 #undef BACK
121 #undef ISSETBACK
122 #undef SNAMES
123
124 /* macros for manipulating states, large version */
125 #define states char *
126 #define CLEAR(v) memset(v, 0, (size_t)m->g->nstates)
127 #define SET0(v, n) ((v)[n] = 0)
128 #define SET1(v, n) ((v)[n] = 1)
129 #define ISSET(v, n) ((v)[n])
130 #define ASSIGN(d, s) memcpy(d, s, (size_t)m->g->nstates)
131 #define EQ(a, b) (memcmp(a, b, (size_t)m->g->nstates) == 0)
132 #define STATEVARS int vn; char *space
133 #define STATESETUP(m, nv) { (m)->space = malloc((size_t)((nv)*(m)->g->nstates)); \
134 if ((m)->space == NULL) return(REG_ESPACE); \
135 (m)->vn = 0; }
136 #define STATETEARDOWN(m) { free((m)->space); }
137 #define SETUP(v) ((v) = &m->space[(size_t)(m->vn++ * m->g->nstates)])
138 #define onestate int
139 #define INIT(o, n) ((o) = (n))
140 #define INC(o) ((o)++)
141 #define ISSTATEIN(v, o) ((v)[o])
142 /* some abbreviations; note that some of these know variable names! */
143 /* do "if I'm here, I can also be there" etc without branches */
144 #define FWD(dst, src, n) ((dst)[here+(n)] |= (src)[here])
145 #define BACK(dst, src, n) ((dst)[here-(n)] |= (src)[here])
146 #define ISSETBACK(v, n) ((v)[here - (n)])
147 /* function names */
148 #define LNAMES /* flag */
149
150 #include "engine.c"
151
152 /*
153 - regexec - interface for matching
154 = extern int regexec(const regex_t *, const char *, size_t, \
155 = regmatch_t [], int);
156 = #define REG_NOTBOL 00001
157 = #define REG_NOTEOL 00002
158 = #define REG_STARTEND 00004
159 = #define REG_TRACE 00400 // tracing of execution
160 = #define REG_LARGE 01000 // force large representation
161 = #define REG_BACKR 02000 // force use of backref code
162 *
163 * We put this here so we can exploit knowledge of the state representation
164 * when choosing which matcher to call. Also, by this point the matchers
165 * have been prototyped.
166 */
167 int /* 0 success, REG_NOMATCH failure */
168 regexec(preg, string, nmatch, pmatch, eflags)
169 const regex_t *preg;
170 const char *string;
171 size_t nmatch;
172 regmatch_t pmatch[];
173 int eflags;
174 {
175 struct re_guts *g = preg->re_g;
176 char *s;
177 #ifdef REDEBUG
178 # define GOODFLAGS(f) (f)
179 #else
180 # define GOODFLAGS(f) ((f)&(REG_NOTBOL|REG_NOTEOL|REG_STARTEND))
181 #endif
182
183 _DIAGASSERT(preg != NULL);
184 _DIAGASSERT(string != NULL);
185
186 if (preg->re_magic != MAGIC1 || g->magic != MAGIC2)
187 return(REG_BADPAT);
188 assert(!(g->iflags&BAD));
189 if (g->iflags&BAD) /* backstop for no-debug case */
190 return(REG_BADPAT);
191 eflags = GOODFLAGS(eflags);
192
193 /* LINTED we believe that the regex routines do not change the string */
194 s = (char *)string;
195
196 if (g->nstates <= CHAR_BIT*sizeof(states1) && !(eflags®_LARGE))
197 return(smatcher(g, s, nmatch, pmatch, eflags));
198 else
199 return(lmatcher(g, s, nmatch, pmatch, eflags));
200 }
201