xref: /netbsd-src/lib/libc/gen/fnmatch.c (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: fnmatch.c,v 1.20 2003/08/07 16:42:48 agc Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 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  * Guido van Rossum.
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 
35 #include <sys/cdefs.h>
36 #if defined(LIBC_SCCS) && !defined(lint)
37 #if 0
38 static char sccsid[] = "@(#)fnmatch.c	8.2 (Berkeley) 4/16/94";
39 #else
40 __RCSID("$NetBSD: fnmatch.c,v 1.20 2003/08/07 16:42:48 agc Exp $");
41 #endif
42 #endif /* LIBC_SCCS and not lint */
43 
44 /*
45  * Function fnmatch() as specified in POSIX 1003.2-1992, section B.6.
46  * Compares a filename or pathname to a pattern.
47  */
48 
49 #include "namespace.h"
50 
51 #include <assert.h>
52 #include <ctype.h>
53 #include <fnmatch.h>
54 #include <string.h>
55 
56 #ifdef __weak_alias
57 __weak_alias(fnmatch,_fnmatch)
58 #endif
59 
60 #define	EOS	'\0'
61 
62 static const char *rangematch __P((const char *, int, int));
63 
64 static __inline int
65 foldcase(int ch, int flags)
66 {
67 
68 	if ((flags & FNM_CASEFOLD) != 0 && isupper(ch))
69 		return (tolower(ch));
70 	return (ch);
71 }
72 
73 #define	FOLDCASE(ch, flags)	foldcase((unsigned char)(ch), (flags))
74 
75 int
76 fnmatch(pattern, string, flags)
77 	const char *pattern, *string;
78 	int flags;
79 {
80 	const char *stringstart;
81 	char c, test;
82 
83 	_DIAGASSERT(pattern != NULL);
84 	_DIAGASSERT(string != NULL);
85 
86 	for (stringstart = string;;)
87 		switch (c = FOLDCASE(*pattern++, flags)) {
88 		case EOS:
89 			if ((flags & FNM_LEADING_DIR) && *string == '/')
90 				return (0);
91 			return (*string == EOS ? 0 : FNM_NOMATCH);
92 		case '?':
93 			if (*string == EOS)
94 				return (FNM_NOMATCH);
95 			if (*string == '/' && (flags & FNM_PATHNAME))
96 				return (FNM_NOMATCH);
97 			if (*string == '.' && (flags & FNM_PERIOD) &&
98 			    (string == stringstart ||
99 			    ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
100 				return (FNM_NOMATCH);
101 			++string;
102 			break;
103 		case '*':
104 			c = FOLDCASE(*pattern, flags);
105 			/* Collapse multiple stars. */
106 			while (c == '*')
107 				c = FOLDCASE(*++pattern, flags);
108 
109 			if (*string == '.' && (flags & FNM_PERIOD) &&
110 			    (string == stringstart ||
111 			    ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
112 				return (FNM_NOMATCH);
113 
114 			/* Optimize for pattern with * at end or before /. */
115 			if (c == EOS) {
116 				if (flags & FNM_PATHNAME)
117 					return ((flags & FNM_LEADING_DIR) ||
118 					    strchr(string, '/') == NULL ?
119 					    0 : FNM_NOMATCH);
120 				else
121 					return (0);
122 			} else if (c == '/' && flags & FNM_PATHNAME) {
123 				if ((string = strchr(string, '/')) == NULL)
124 					return (FNM_NOMATCH);
125 				break;
126 			}
127 
128 			/* General case, use recursion. */
129 			while ((test = FOLDCASE(*string, flags)) != EOS) {
130 				if (!fnmatch(pattern, string,
131 					     flags & ~FNM_PERIOD))
132 					return (0);
133 				if (test == '/' && flags & FNM_PATHNAME)
134 					break;
135 				++string;
136 			}
137 			return (FNM_NOMATCH);
138 		case '[':
139 			if (*string == EOS)
140 				return (FNM_NOMATCH);
141 			if (*string == '/' && flags & FNM_PATHNAME)
142 				return (FNM_NOMATCH);
143 			if ((pattern =
144 			    rangematch(pattern, FOLDCASE(*string, flags),
145 				       flags)) == NULL)
146 				return (FNM_NOMATCH);
147 			++string;
148 			break;
149 		case '\\':
150 			if (!(flags & FNM_NOESCAPE)) {
151 				if ((c = FOLDCASE(*pattern++, flags)) == EOS) {
152 					c = '\\';
153 					--pattern;
154 				}
155 			}
156 			/* FALLTHROUGH */
157 		default:
158 			if (c != FOLDCASE(*string++, flags))
159 				return (FNM_NOMATCH);
160 			break;
161 		}
162 	/* NOTREACHED */
163 }
164 
165 static const char *
166 rangematch(pattern, test, flags)
167 	const char *pattern;
168 	int test, flags;
169 {
170 	int negate, ok;
171 	char c, c2;
172 
173 	_DIAGASSERT(pattern != NULL);
174 
175 	/*
176 	 * A bracket expression starting with an unquoted circumflex
177 	 * character produces unspecified results (IEEE 1003.2-1992,
178 	 * 3.13.2).  This implementation treats it like '!', for
179 	 * consistency with the regular expression syntax.
180 	 * J.T. Conklin (conklin@ngai.kaleida.com)
181 	 */
182 	if ((negate = (*pattern == '!' || *pattern == '^')) != 0)
183 		++pattern;
184 
185 	for (ok = 0; (c = FOLDCASE(*pattern++, flags)) != ']';) {
186 		if (c == '\\' && !(flags & FNM_NOESCAPE))
187 			c = FOLDCASE(*pattern++, flags);
188 		if (c == EOS)
189 			return (NULL);
190 		if (*pattern == '-'
191 		    && (c2 = FOLDCASE(*(pattern+1), flags)) != EOS &&
192 		        c2 != ']') {
193 			pattern += 2;
194 			if (c2 == '\\' && !(flags & FNM_NOESCAPE))
195 				c2 = FOLDCASE(*pattern++, flags);
196 			if (c2 == EOS)
197 				return (NULL);
198 			if (c <= test && test <= c2)
199 				ok = 1;
200 		} else if (c == test)
201 			ok = 1;
202 	}
203 	return (ok == negate ? NULL : pattern);
204 }
205