xref: /freebsd/sys/libkern/fnmatch.c (revision 6780ab54325a71e7e70112b11657973edde8655e)
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  * $FreeBSD$
37  */
38 
39 /*
40  * Function fnmatch() as specified in POSIX 1003.2-1992, section B.6.
41  * Compares a filename or pathname to a pattern.
42  */
43 
44 #include <sys/param.h>
45 #include <sys/ctype.h>
46 #include <sys/libkern.h>
47 
48 #define	EOS	'\0'
49 
50 #define RANGE_MATCH     1
51 #define RANGE_NOMATCH   0
52 #define RANGE_ERROR     (-1)
53 
54 static int rangematch(const char *, char, int, char **);
55 
56 int
57 fnmatch(pattern, string, flags)
58 	const char *pattern, *string;
59 	int flags;
60 {
61 	const char *stringstart;
62 	char *newp;
63 	char c, test;
64 
65 	for (stringstart = string;;)
66 		switch (c = *pattern++) {
67 		case EOS:
68 			if ((flags & FNM_LEADING_DIR) && *string == '/')
69 				return (0);
70 			return (*string == EOS ? 0 : FNM_NOMATCH);
71 		case '?':
72 			if (*string == EOS)
73 				return (FNM_NOMATCH);
74 			if (*string == '/' && (flags & FNM_PATHNAME))
75 				return (FNM_NOMATCH);
76 			if (*string == '.' && (flags & FNM_PERIOD) &&
77 			    (string == stringstart ||
78 			    ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
79 				return (FNM_NOMATCH);
80 			++string;
81 			break;
82 		case '*':
83 			c = *pattern;
84 			/* Collapse multiple stars. */
85 			while (c == '*')
86 				c = *++pattern;
87 
88 			if (*string == '.' && (flags & FNM_PERIOD) &&
89 			    (string == stringstart ||
90 			    ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
91 				return (FNM_NOMATCH);
92 
93 			/* Optimize for pattern with * at end or before /. */
94 			if (c == EOS)
95 				if (flags & FNM_PATHNAME)
96 					return ((flags & FNM_LEADING_DIR) ||
97 					    index(string, '/') == NULL ?
98 					    0 : FNM_NOMATCH);
99 				else
100 					return (0);
101 			else if (c == '/' && flags & FNM_PATHNAME) {
102 				if ((string = index(string, '/')) == NULL)
103 					return (FNM_NOMATCH);
104 				break;
105 			}
106 
107 			/* General case, use recursion. */
108 			while ((test = *string) != EOS) {
109 				if (!fnmatch(pattern, string, flags & ~FNM_PERIOD))
110 					return (0);
111 				if (test == '/' && flags & FNM_PATHNAME)
112 					break;
113 				++string;
114 			}
115 			return (FNM_NOMATCH);
116 		case '[':
117 			if (*string == EOS)
118 				return (FNM_NOMATCH);
119 			if (*string == '/' && (flags & FNM_PATHNAME))
120 				return (FNM_NOMATCH);
121 			if (*string == '.' && (flags & FNM_PERIOD) &&
122 			    (string == stringstart ||
123 			    ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
124 				return (FNM_NOMATCH);
125 
126 			switch (rangematch(pattern, *string, flags, &newp)) {
127 			case RANGE_ERROR:
128 				goto norm;
129 			case RANGE_MATCH:
130 				pattern = newp;
131 				break;
132 			case RANGE_NOMATCH:
133 				return (FNM_NOMATCH);
134 			}
135 			++string;
136 			break;
137 		case '\\':
138 			if (!(flags & FNM_NOESCAPE)) {
139 				if ((c = *pattern++) == EOS) {
140 					c = '\\';
141 					--pattern;
142 				}
143 			}
144 			/* FALLTHROUGH */
145 		default:
146 		norm:
147 			if (c == *string)
148 				;
149 			else if ((flags & FNM_CASEFOLD) &&
150 				 (tolower((unsigned char)c) ==
151 				  tolower((unsigned char)*string)))
152 				;
153 			else
154 				return (FNM_NOMATCH);
155 			string++;
156 			break;
157 		}
158 	/* NOTREACHED */
159 }
160 
161 static int
162 rangematch(pattern, test, flags, newp)
163 	const char *pattern;
164 	char test;
165 	int flags;
166 	char **newp;
167 {
168 	int negate, ok;
169 	char c, c2;
170 
171 	/*
172 	 * A bracket expression starting with an unquoted circumflex
173 	 * character produces unspecified results (IEEE 1003.2-1992,
174 	 * 3.13.2).  This implementation treats it like '!', for
175 	 * consistency with the regular expression syntax.
176 	 * J.T. Conklin (conklin@ngai.kaleida.com)
177 	 */
178 	if ( (negate = (*pattern == '!' || *pattern == '^')) )
179 		++pattern;
180 
181 	if (flags & FNM_CASEFOLD)
182 		test = tolower((unsigned char)test);
183 
184 	/*
185 	 * A right bracket shall lose its special meaning and represent
186 	 * itself in a bracket expression if it occurs first in the list.
187 	 * -- POSIX.2 2.8.3.2
188 	 */
189 	ok = 0;
190 	c = *pattern++;
191 	do {
192 		if (c == '\\' && !(flags & FNM_NOESCAPE))
193 			c = *pattern++;
194 		if (c == EOS)
195 			return (RANGE_ERROR);
196 
197 		if (c == '/' && (flags & FNM_PATHNAME))
198 			return (RANGE_NOMATCH);
199 
200 		if (flags & FNM_CASEFOLD)
201 			c = tolower((unsigned char)c);
202 
203 		if (*pattern == '-'
204 		    && (c2 = *(pattern+1)) != EOS && c2 != ']') {
205 			pattern += 2;
206 			if (c2 == '\\' && !(flags & FNM_NOESCAPE))
207 				c2 = *pattern++;
208 			if (c2 == EOS)
209 				return (RANGE_ERROR);
210 
211 			if (flags & FNM_CASEFOLD)
212 				c2 = tolower((unsigned char)c2);
213 
214 			if (c <= test && test <= c2)
215 				ok = 1;
216 		} else if (c == test)
217 			ok = 1;
218 	} while ((c = *pattern++) != ']');
219 
220 	*newp = (char *)(uintptr_t)pattern;
221 	return (ok == negate ? RANGE_NOMATCH : RANGE_MATCH);
222 }
223