xref: /dragonfly/sys/libkern/fnmatch.c (revision 9bb2a92d)
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: src/sys/libkern/fnmatch.c,v 1.17 2003/06/11 05:23:04 obrien Exp $
37  * $DragonFly: src/sys/libkern/fnmatch.c,v 1.2 2004/01/06 01:05:52 dillon Exp $
38  */
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 #define MAXNEST		20
56 
57 static int rangematch(const char *, char, int, char **);
58 
59 int
60 _fnmatch(const char *pattern, const char *string, int flags, int nesting)
61 {
62 	const char *stringstart;
63 	char *newp;
64 	char c, test;
65 
66 	if (nesting == MAXNEST)
67 		return (FNM_NOMATCH);
68 
69 	for (stringstart = string;;) {
70 		switch (c = *pattern++) {
71 		case EOS:
72 			if ((flags & FNM_LEADING_DIR) && *string == '/')
73 				return (0);
74 			return (*string == EOS ? 0 : FNM_NOMATCH);
75 		case '?':
76 			if (*string == EOS)
77 				return (FNM_NOMATCH);
78 			if (*string == '/' && (flags & FNM_PATHNAME))
79 				return (FNM_NOMATCH);
80 			if (*string == '.' && (flags & FNM_PERIOD) &&
81 			    (string == stringstart ||
82 			    ((flags & FNM_PATHNAME) && *(string - 1) == '/'))) {
83 				return (FNM_NOMATCH);
84 			}
85 			++string;
86 			break;
87 		case '*':
88 			c = *pattern;
89 			/* Collapse multiple stars. */
90 			while (c == '*')
91 				c = *++pattern;
92 
93 			if (*string == '.' && (flags & FNM_PERIOD) &&
94 			    (string == stringstart ||
95 			    ((flags & FNM_PATHNAME) && *(string - 1) == '/'))) {
96 				return (FNM_NOMATCH);
97 			}
98 
99 			/* Optimize for pattern with * at end or before /. */
100 			if (c == EOS) {
101 				if (flags & FNM_PATHNAME) {
102 					return ((flags & FNM_LEADING_DIR) ||
103 					    index(string, '/') == NULL ?
104 					    0 : FNM_NOMATCH);
105 				} else {
106 					return (0);
107 				}
108 			} else if (c == '/' && flags & FNM_PATHNAME) {
109 				if ((string = index(string, '/')) == NULL)
110 					return (FNM_NOMATCH);
111 				break;
112 			}
113 
114 			/* General case, use recursion. */
115 			while ((test = *string) != EOS) {
116 				if (!_fnmatch(pattern, string, flags & ~FNM_PERIOD, nesting + 1))
117 					return (0);
118 				if (test == '/' && flags & FNM_PATHNAME)
119 					break;
120 				++string;
121 			}
122 			return (FNM_NOMATCH);
123 		case '[':
124 			if (*string == EOS)
125 				return (FNM_NOMATCH);
126 			if (*string == '/' && (flags & FNM_PATHNAME))
127 				return (FNM_NOMATCH);
128 			if (*string == '.' && (flags & FNM_PERIOD) &&
129 			    (string == stringstart ||
130 			    ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
131 				return (FNM_NOMATCH);
132 
133 			switch (rangematch(pattern, *string, flags, &newp)) {
134 			case RANGE_ERROR:
135 				goto norm;
136 			case RANGE_MATCH:
137 				pattern = newp;
138 				break;
139 			case RANGE_NOMATCH:
140 				return (FNM_NOMATCH);
141 			}
142 			++string;
143 			break;
144 		case '\\':
145 			if (!(flags & FNM_NOESCAPE)) {
146 				if ((c = *pattern++) == EOS) {
147 					c = '\\';
148 					--pattern;
149 				}
150 			}
151 			/* FALLTHROUGH */
152 		default:
153 		norm:
154 			if (c == *string) {
155 				;
156 			} else if ((flags & FNM_CASEFOLD) &&
157 				 (tolower((unsigned char)c) ==
158 				  tolower((unsigned char)*string))) {
159 				;
160 			} else {
161 				return (FNM_NOMATCH);
162 			}
163 			string++;
164 			break;
165 		}
166 	}
167 	/* NOTREACHED */
168 }
169 
170 static int
171 rangematch(const char *pattern, char test, int flags, char **newp)
172 {
173 	int negate, ok;
174 	char c, c2;
175 
176 	/*
177 	 * A bracket expression starting with an unquoted circumflex
178 	 * character produces unspecified results (IEEE 1003.2-1992,
179 	 * 3.13.2).  This implementation treats it like '!', for
180 	 * consistency with the regular expression syntax.
181 	 * J.T. Conklin (conklin@ngai.kaleida.com)
182 	 */
183 	if ((negate = (*pattern == '!' || *pattern == '^')) != 0)
184 		++pattern;
185 
186 	if (flags & FNM_CASEFOLD)
187 		test = tolower((unsigned char)test);
188 
189 	/*
190 	 * A right bracket shall lose its special meaning and represent
191 	 * itself in a bracket expression if it occurs first in the list.
192 	 * -- POSIX.2 2.8.3.2
193 	 */
194 	ok = 0;
195 	c = *pattern++;
196 	do {
197 		if (c == '\\' && !(flags & FNM_NOESCAPE))
198 			c = *pattern++;
199 		if (c == EOS)
200 			return (RANGE_ERROR);
201 
202 		if (c == '/' && (flags & FNM_PATHNAME))
203 			return (RANGE_NOMATCH);
204 
205 		if (flags & FNM_CASEFOLD)
206 			c = tolower((unsigned char)c);
207 
208 		if (*pattern == '-'
209 		    && (c2 = *(pattern+1)) != EOS && c2 != ']') {
210 			pattern += 2;
211 			if (c2 == '\\' && !(flags & FNM_NOESCAPE))
212 				c2 = *pattern++;
213 			if (c2 == EOS)
214 				return (RANGE_ERROR);
215 
216 			if (flags & FNM_CASEFOLD)
217 				c2 = tolower((unsigned char)c2);
218 
219 			if (c <= test && test <= c2)
220 				ok = 1;
221 		} else if (c == test) {
222 			ok = 1;
223 		}
224 	} while ((c = *pattern++) != ']');
225 
226 	*newp = (char *)(uintptr_t)pattern;
227 	return (ok == negate ? RANGE_NOMATCH : RANGE_MATCH);
228 }
229 
230