xref: /netbsd-src/sys/lib/libkern/pmatch.c (revision 5e4c038a45edbc7d63b7c2daa76e29f88b64a4e3)
1 /*	$NetBSD: pmatch.c,v 1.2 2001/11/15 09:48:21 lukem Exp $	*/
2 
3 /*-
4  * Copyright (c) 1980, 1991 The Regents of the University of California.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/param.h>
37 #include <lib/libkern/libkern.h>
38 /*
39  * pmatch():
40  *	Return 2 on exact match.
41  *	Return 1 on substring match.
42  *	Return 0 on no match.
43  *	Return -1 on error.
44  * *estr will point to the end of thelongest exact or substring match.
45  */
46 int
47 pmatch(string, pattern, estr)
48 	const char *string, *pattern, **estr;
49 {
50 	u_char stringc, patternc, rangec;
51 	int match, negate_range;
52 	const char *oestr, *pestr, *testr;
53 
54 	if (estr == NULL)
55 		estr = &testr;
56 
57 	for (;; ++string) {
58 		stringc = *string;
59 		switch (patternc = *pattern++) {
60 		case 0:
61 			*estr = string;
62 			return stringc == '\0' ? 2 : 1;
63 		case '?':
64 			if (stringc == '\0')
65 				return 0;
66 			*estr = string;
67 			break;
68 		case '*':
69 			if (!*pattern) {
70 				while (*string)
71 					string++;
72 				*estr = string;
73 				return 2;
74 			}
75 			oestr = *estr;
76 			pestr = NULL;
77 
78 			do {
79 				switch (pmatch(string, pattern, estr)) {
80 				case -1:
81 					return -1;
82 				case 0:
83 					break;
84 				case 1:
85 					pestr = *estr;
86 					break;
87 				case 2:
88 					return 2;
89 				default:
90 					return -1;
91 				}
92 				*estr = string;
93 			}
94 			while (*string++);
95 
96 			if (pestr) {
97 				*estr = pestr;
98 				return 1;
99 			} else {
100 				*estr = oestr;
101 				return 0;
102 			}
103 
104 		case '[':
105 			match = 0;
106 			if ((negate_range = (*pattern == '^')) != 0)
107 				pattern++;
108 			while ((rangec = *pattern++) != '\0') {
109 				if (rangec == ']')
110 					break;
111 				if (match)
112 					continue;
113 				if (rangec == '-' && *(pattern - 2) != '[' &&
114 				    *pattern != ']') {
115 					match =
116 					    stringc <= (u_char)*pattern &&
117 					    (u_char)*(pattern - 2) <= stringc;
118 					pattern++;
119 				} else
120 					match = (stringc == rangec);
121 			}
122 			if (rangec == 0)
123 				return -1;
124 			if (match == negate_range)
125 				return 0;
126 			*estr = string;
127 			break;
128 		default:
129 			if (patternc != stringc)
130 				return 0;
131 			*estr = string;
132 			break;
133 		}
134 	}
135 }
136