xref: /haiku/src/system/libroot/posix/string/strcasecmp.c (revision 4a55cc230cf7566cadcbb23b1928eefff8aea9a2)
1 /*
2  * Copyright (c) 1987, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 
35 #include <ctype.h>
36 #include <strings.h>
37 
38 
39 int
40 strcasecmp(const char *s1, const char *s2)
41 {
42 	const u_char *us1 = (const u_char *)s1;
43 	const u_char *us2 = (const u_char *)s2;
44 
45 	while (tolower(*us1) == tolower(*us2++)) {
46 		if (*us1++ == '\0')
47 			return 0;
48 	}
49 
50 	return tolower(*us1) - tolower(*--us2);
51 }
52 
53 
54 int
55 strncasecmp(const char *s1, const char *s2, size_t n)
56 {
57 	if (n != 0) {
58 		const u_char *us1 = (const u_char *)s1;
59 		const u_char *us2 = (const u_char *)s2;
60 
61 		do {
62 			if (tolower(*us1) != tolower(*us2++))
63 				return tolower(*us1) - tolower(*--us2);
64 			if (*us1++ == '\0')
65 				break;
66 		} while (--n != 0);
67 	}
68 	return 0;
69 }
70 
71 
72 int
73 strcasecmp_l(const char *s1, const char *s2, locale_t locale)
74 {
75 	const u_char *us1 = (const u_char *)s1;
76 	const u_char *us2 = (const u_char *)s2;
77 
78 	while (tolower_l(*us1, locale) == tolower_l(*us2++, locale)) {
79 		if (*us1++ == '\0')
80 			return 0;
81 	}
82 
83 	return tolower_l(*us1, locale) - tolower_l(*--us2, locale);
84 }
85 
86 
87 int
88 strncasecmp_l(const char *s1, const char *s2, size_t n, locale_t locale)
89 {
90 	if (n != 0) {
91 		const u_char *us1 = (const u_char *)s1;
92 		const u_char *us2 = (const u_char *)s2;
93 
94 		do {
95 			if (tolower_l(*us1, locale) != tolower_l(*us2++, locale))
96 				return tolower_l(*us1, locale) - tolower_l(*--us2, locale);
97 			if (*us1++ == '\0')
98 				break;
99 		} while (--n != 0);
100 	}
101 	return 0;
102 }
103