xref: /freebsd/lib/libc/string/strcasecmp.c (revision 1db64f89363c97858961c4df0b7d02f3223723cf)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1987, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Copyright (c) 2011 The FreeBSD Foundation
8  *
9  * Portions of this software were developed by David Chisnall
10  * under sponsorship from the FreeBSD Foundation.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. 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 <strings.h>
38 #include <ctype.h>
39 #include "xlocale_private.h"
40 
41 int
42 strcasecmp_l(const char *s1, const char *s2, locale_t locale)
43 {
44 	const u_char
45 			*us1 = (const u_char *)s1,
46 			*us2 = (const u_char *)s2;
47 	FIX_LOCALE(locale);
48 
49 	while (tolower_l(*us1, locale) == tolower_l(*us2++, locale))
50 		if (*us1++ == '\0')
51 			return (0);
52 	return (tolower_l(*us1, locale) - tolower_l(*--us2, locale));
53 }
54 int
55 strcasecmp(const char *s1, const char *s2)
56 {
57 	return strcasecmp_l(s1, s2, __get_locale());
58 }
59 
60 int
61 strncasecmp_l(const char *s1, const char *s2, size_t n, locale_t locale)
62 {
63 	FIX_LOCALE(locale);
64 	if (n != 0) {
65 		const u_char
66 				*us1 = (const u_char *)s1,
67 				*us2 = (const u_char *)s2;
68 
69 		do {
70 			if (tolower_l(*us1, locale) != tolower_l(*us2++, locale))
71 				return (tolower_l(*us1, locale) - tolower_l(*--us2, locale));
72 			if (*us1++ == '\0')
73 				break;
74 		} while (--n != 0);
75 	}
76 	return (0);
77 }
78 
79 int
80 strncasecmp(const char *s1, const char *s2, size_t n)
81 {
82 	return strncasecmp_l(s1, s2, n, __get_locale());
83 }
84