1 /* $NetBSD: regexec.c,v 1.26 2021/02/26 19:24:47 christos Exp $ */
2
3 /*-
4 * SPDX-License-Identifier: BSD-3-Clause
5 *
6 * Copyright (c) 1992, 1993, 1994 Henry Spencer.
7 * Copyright (c) 1992, 1993, 1994
8 * The Regents of the University of California. All rights reserved.
9 *
10 * This code is derived from software contributed to Berkeley by
11 * Henry Spencer.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * @(#)regexec.c 8.3 (Berkeley) 3/20/94
38 */
39
40 #if HAVE_NBTOOL_CONFIG_H
41 #include "nbtool_config.h"
42 #endif
43
44 #include <sys/cdefs.h>
45 #if 0
46 static char sccsid[] = "@(#)regexec.c 8.3 (Berkeley) 3/20/94";
47 __FBSDID("$FreeBSD: head/lib/libc/regex/regexec.c 326025 2017-11-20 19:49:47Z pfg $");
48 #endif
49 __RCSID("$NetBSD: regexec.c,v 1.26 2021/02/26 19:24:47 christos Exp $");
50
51 /*
52 * the outer shell of regexec()
53 *
54 * This file includes engine.c three times, after muchos fiddling with the
55 * macros that code uses. This lets the same code operate on two different
56 * representations for state sets and characters.
57 */
58
59 #ifndef LIBHACK
60 #include "namespace.h"
61 #endif
62 #include <sys/types.h>
63 #include <stdio.h>
64 #include <stdlib.h>
65 #include <string.h>
66 #include <limits.h>
67 #include <ctype.h>
68 #include <regex.h>
69
70 #if defined(__weak_alias) && !defined(LIBHACK)
__weak_alias(regexec,_regexec)71 __weak_alias(regexec,_regexec)
72 #endif
73
74 #include "utils.h"
75 #include "regex2.h"
76
77 static __inline size_t
78 xmbrtowc(wint_t *wi, const char *s, size_t n, mbstate_t *mbs, wint_t dummy)
79 {
80 #ifdef NLS
81 size_t nr;
82 wchar_t wc;
83
84 nr = mbrtowc(&wc, s, n, mbs);
85 if (wi != NULL)
86 *wi = wc;
87 if (nr == 0)
88 return (1);
89 else if (nr == (size_t)-1 || nr == (size_t)-2) {
90 memset(mbs, 0, sizeof(*mbs));
91 if (wi != NULL)
92 *wi = dummy;
93 return (1);
94 } else
95 return (nr);
96 #else
97 if (wi)
98 *wi = *s;
99 return 1;
100 #endif
101 }
102
103 static __inline size_t
xmbrtowc_dummy(wint_t * wi,const char * s,size_t n __unused,mbstate_t * mbs __unused,wint_t dummy __unused)104 xmbrtowc_dummy(wint_t *wi,
105 const char *s,
106 size_t n __unused,
107 mbstate_t *mbs __unused,
108 wint_t dummy __unused)
109 {
110
111 if (wi != NULL)
112 *wi = (unsigned char)*s;
113 return (1);
114 }
115
116 /* macros for manipulating states, small version */
117 #define states long
118 #define states1 states /* for later use in regexec() decision */
119 #define CLEAR(v) ((v) = 0)
120 #define SET0(v, n) ((v) &= ~((unsigned long)1 << (n)))
121 #define SET1(v, n) ((v) |= (unsigned long)1 << (n))
122 #define ISSET(v, n) (((v) & ((unsigned long)1 << (n))) != 0)
123 #define ASSIGN(d, s) ((d) = (s))
124 #define EQ(a, b) ((a) == (b))
125 #define STATEVARS long dummy /* dummy version */
126 #define STATESETUP(m, n) /* nothing */
127 #define STATETEARDOWN(m) /* nothing */
128 #define SETUP(v) ((v) = 0)
129 #define onestate long
130 #define INIT(o, n) ((o) = (unsigned long)1 << (n))
131 #define INC(o) ((o) <<= 1)
132 #define ISSTATEIN(v, o) (((v) & (o)) != 0)
133 /* some abbreviations; note that some of these know variable names! */
134 /* do "if I'm here, I can also be there" etc without branches */
135 #define FWD(dst, src, n) ((dst) |= ((unsigned long)(src)&(here)) << (n))
136 #define BACK(dst, src, n) ((dst) |= ((unsigned long)(src)&(here)) >> (n))
137 #define ISSETBACK(v, n) (((v) & ((unsigned long)here >> (n))) != 0)
138 /* no multibyte support */
139 #define XMBRTOWC xmbrtowc_dummy
140 #define ZAPSTATE(mbs) ((void)(mbs))
141 /* function names */
142 #define SNAMES /* engine.c looks after details */
143
144 #include "engine.c"
145
146 /* now undo things */
147 #undef states
148 #undef CLEAR
149 #undef SET0
150 #undef SET1
151 #undef ISSET
152 #undef ASSIGN
153 #undef EQ
154 #undef STATEVARS
155 #undef STATESETUP
156 #undef STATETEARDOWN
157 #undef SETUP
158 #undef onestate
159 #undef INIT
160 #undef INC
161 #undef ISSTATEIN
162 #undef FWD
163 #undef BACK
164 #undef ISSETBACK
165 #undef SNAMES
166 #undef XMBRTOWC
167 #undef ZAPSTATE
168
169 /* macros for manipulating states, large version */
170 #define states char *
171 #define CLEAR(v) memset(v, 0, m->g->nstates)
172 #define SET0(v, n) ((v)[n] = 0)
173 #define SET1(v, n) ((v)[n] = 1)
174 #define ISSET(v, n) ((v)[n])
175 #define ASSIGN(d, s) memcpy(d, s, m->g->nstates)
176 #define EQ(a, b) (memcmp(a, b, m->g->nstates) == 0)
177 #define STATEVARS long vn; char *space
178 #define STATESETUP(m, nv) { (m)->space = malloc((nv)*(m)->g->nstates); \
179 if ((m)->space == NULL) return(REG_ESPACE); \
180 (m)->vn = 0; }
181 #define STATETEARDOWN(m) { free((m)->space); }
182 #define SETUP(v) ((v) = &m->space[m->vn++ * m->g->nstates])
183 #define onestate long
184 #define INIT(o, n) ((o) = (n))
185 #define INC(o) ((o)++)
186 #define ISSTATEIN(v, o) ((v)[o])
187 /* some abbreviations; note that some of these know variable names! */
188 /* do "if I'm here, I can also be there" etc without branches */
189 #define FWD(dst, src, n) ((dst)[here+(n)] |= (src)[here])
190 #define BACK(dst, src, n) ((dst)[here-(n)] |= (src)[here])
191 #define ISSETBACK(v, n) ((v)[here - (n)])
192 /* no multibyte support */
193 #define XMBRTOWC xmbrtowc_dummy
194 #define ZAPSTATE(mbs) ((void)(mbs))
195 /* function names */
196 #define LNAMES /* flag */
197
198 #include "engine.c"
199
200 /* multibyte character & large states version */
201 #undef LNAMES
202 #undef XMBRTOWC
203 #undef ZAPSTATE
204 #define XMBRTOWC xmbrtowc
205 #define ZAPSTATE(mbs) memset((mbs), 0, sizeof(*(mbs)))
206 #define MNAMES
207
208 #include "engine.c"
209
210 /*
211 - regexec - interface for matching
212 = extern int regexec(const regex_t *, const char *, size_t, \
213 = regmatch_t [], int);
214 = #define REG_NOTBOL 00001
215 = #define REG_NOTEOL 00002
216 = #define REG_STARTEND 00004
217 = #define REG_TRACE 00400 // tracing of execution
218 = #define REG_LARGE 01000 // force large representation
219 = #define REG_BACKR 02000 // force use of backref code
220 *
221 * We put this here so we can exploit knowledge of the state representation
222 * when choosing which matcher to call. Also, by this point the matchers
223 * have been prototyped.
224 */
225 int /* 0 success, REG_NOMATCH failure */
regexec(const regex_t * __restrict preg,const char * __restrict string,size_t nmatch,regmatch_t pmatch[__restrict],int eflags)226 regexec(const regex_t * __restrict preg,
227 const char * __restrict string,
228 size_t nmatch,
229 regmatch_t pmatch[__restrict],
230 int eflags)
231 {
232 struct re_guts *g = preg->re_g;
233 #ifdef REDEBUG
234 # define GOODFLAGS(f) (f)
235 #else
236 # define GOODFLAGS(f) ((f)&(REG_NOTBOL|REG_NOTEOL|REG_STARTEND))
237 #endif
238 _DIAGASSERT(preg != NULL);
239 _DIAGASSERT(string != NULL);
240
241 if (preg->re_magic != MAGIC1 || g->magic != MAGIC2)
242 return(REG_BADPAT);
243 assert(!(g->iflags&BAD));
244 if (g->iflags&BAD) /* backstop for no-debug case */
245 return(REG_BADPAT);
246 eflags = GOODFLAGS(eflags);
247
248 if (MB_CUR_MAX > 1)
249 return(mmatcher(g, string, nmatch, pmatch, eflags));
250 else if (g->nstates <= CHAR_BIT*sizeof(states1) && !(eflags®_LARGE))
251 return(smatcher(g, string, nmatch, pmatch, eflags));
252 else
253 return(lmatcher(g, string, nmatch, pmatch, eflags));
254 }
255