xref: /freebsd/sys/libkern/fnmatch.c (revision 7660b554bc59a07be0431c17e0e33815818baa69)
1 /*
2  * Copyright (c) 1989, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Guido van Rossum.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 /*
41  * Function fnmatch() as specified in POSIX 1003.2-1992, section B.6.
42  * Compares a filename or pathname to a pattern.
43  */
44 
45 #include <sys/param.h>
46 #include <sys/ctype.h>
47 #include <sys/libkern.h>
48 
49 #define	EOS	'\0'
50 
51 #define RANGE_MATCH     1
52 #define RANGE_NOMATCH   0
53 #define RANGE_ERROR     (-1)
54 
55 static int rangematch(const char *, char, int, char **);
56 
57 int
58 fnmatch(pattern, string, flags)
59 	const char *pattern, *string;
60 	int flags;
61 {
62 	const char *stringstart;
63 	char *newp;
64 	char c, test;
65 
66 	for (stringstart = string;;)
67 		switch (c = *pattern++) {
68 		case EOS:
69 			if ((flags & FNM_LEADING_DIR) && *string == '/')
70 				return (0);
71 			return (*string == EOS ? 0 : FNM_NOMATCH);
72 		case '?':
73 			if (*string == EOS)
74 				return (FNM_NOMATCH);
75 			if (*string == '/' && (flags & FNM_PATHNAME))
76 				return (FNM_NOMATCH);
77 			if (*string == '.' && (flags & FNM_PERIOD) &&
78 			    (string == stringstart ||
79 			    ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
80 				return (FNM_NOMATCH);
81 			++string;
82 			break;
83 		case '*':
84 			c = *pattern;
85 			/* Collapse multiple stars. */
86 			while (c == '*')
87 				c = *++pattern;
88 
89 			if (*string == '.' && (flags & FNM_PERIOD) &&
90 			    (string == stringstart ||
91 			    ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
92 				return (FNM_NOMATCH);
93 
94 			/* Optimize for pattern with * at end or before /. */
95 			if (c == EOS)
96 				if (flags & FNM_PATHNAME)
97 					return ((flags & FNM_LEADING_DIR) ||
98 					    index(string, '/') == NULL ?
99 					    0 : FNM_NOMATCH);
100 				else
101 					return (0);
102 			else if (c == '/' && flags & FNM_PATHNAME) {
103 				if ((string = index(string, '/')) == NULL)
104 					return (FNM_NOMATCH);
105 				break;
106 			}
107 
108 			/* General case, use recursion. */
109 			while ((test = *string) != EOS) {
110 				if (!fnmatch(pattern, string, flags & ~FNM_PERIOD))
111 					return (0);
112 				if (test == '/' && flags & FNM_PATHNAME)
113 					break;
114 				++string;
115 			}
116 			return (FNM_NOMATCH);
117 		case '[':
118 			if (*string == EOS)
119 				return (FNM_NOMATCH);
120 			if (*string == '/' && (flags & FNM_PATHNAME))
121 				return (FNM_NOMATCH);
122 			if (*string == '.' && (flags & FNM_PERIOD) &&
123 			    (string == stringstart ||
124 			    ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
125 				return (FNM_NOMATCH);
126 
127 			switch (rangematch(pattern, *string, flags, &newp)) {
128 			case RANGE_ERROR:
129 				goto norm;
130 			case RANGE_MATCH:
131 				pattern = newp;
132 				break;
133 			case RANGE_NOMATCH:
134 				return (FNM_NOMATCH);
135 			}
136 			++string;
137 			break;
138 		case '\\':
139 			if (!(flags & FNM_NOESCAPE)) {
140 				if ((c = *pattern++) == EOS) {
141 					c = '\\';
142 					--pattern;
143 				}
144 			}
145 			/* FALLTHROUGH */
146 		default:
147 		norm:
148 			if (c == *string)
149 				;
150 			else if ((flags & FNM_CASEFOLD) &&
151 				 (tolower((unsigned char)c) ==
152 				  tolower((unsigned char)*string)))
153 				;
154 			else
155 				return (FNM_NOMATCH);
156 			string++;
157 			break;
158 		}
159 	/* NOTREACHED */
160 }
161 
162 static int
163 rangematch(pattern, test, flags, newp)
164 	const char *pattern;
165 	char test;
166 	int flags;
167 	char **newp;
168 {
169 	int negate, ok;
170 	char c, c2;
171 
172 	/*
173 	 * A bracket expression starting with an unquoted circumflex
174 	 * character produces unspecified results (IEEE 1003.2-1992,
175 	 * 3.13.2).  This implementation treats it like '!', for
176 	 * consistency with the regular expression syntax.
177 	 * J.T. Conklin (conklin@ngai.kaleida.com)
178 	 */
179 	if ( (negate = (*pattern == '!' || *pattern == '^')) )
180 		++pattern;
181 
182 	if (flags & FNM_CASEFOLD)
183 		test = tolower((unsigned char)test);
184 
185 	/*
186 	 * A right bracket shall lose its special meaning and represent
187 	 * itself in a bracket expression if it occurs first in the list.
188 	 * -- POSIX.2 2.8.3.2
189 	 */
190 	ok = 0;
191 	c = *pattern++;
192 	do {
193 		if (c == '\\' && !(flags & FNM_NOESCAPE))
194 			c = *pattern++;
195 		if (c == EOS)
196 			return (RANGE_ERROR);
197 
198 		if (c == '/' && (flags & FNM_PATHNAME))
199 			return (RANGE_NOMATCH);
200 
201 		if (flags & FNM_CASEFOLD)
202 			c = tolower((unsigned char)c);
203 
204 		if (*pattern == '-'
205 		    && (c2 = *(pattern+1)) != EOS && c2 != ']') {
206 			pattern += 2;
207 			if (c2 == '\\' && !(flags & FNM_NOESCAPE))
208 				c2 = *pattern++;
209 			if (c2 == EOS)
210 				return (RANGE_ERROR);
211 
212 			if (flags & FNM_CASEFOLD)
213 				c2 = tolower((unsigned char)c2);
214 
215 			if (c <= test && test <= c2)
216 				ok = 1;
217 		} else if (c == test)
218 			ok = 1;
219 	} while ((c = *pattern++) != ']');
220 
221 	*newp = (char *)(uintptr_t)pattern;
222 	return (ok == negate ? RANGE_NOMATCH : RANGE_MATCH);
223 }
224