xref: /netbsd-src/common/lib/libc/string/strcasecmp.c (revision 37c9f0a654f1f14465cded15c4577522438c5585)
1*37c9f0a6Schristos /*	$NetBSD: strcasecmp.c,v 1.1 2005/12/20 19:28:52 christos Exp $	*/
2*37c9f0a6Schristos 
3*37c9f0a6Schristos /*
4*37c9f0a6Schristos  * Copyright (c) 1987, 1993
5*37c9f0a6Schristos  *	The Regents of the University of California.  All rights reserved.
6*37c9f0a6Schristos  *
7*37c9f0a6Schristos  * Redistribution and use in source and binary forms, with or without
8*37c9f0a6Schristos  * modification, are permitted provided that the following conditions
9*37c9f0a6Schristos  * are met:
10*37c9f0a6Schristos  * 1. Redistributions of source code must retain the above copyright
11*37c9f0a6Schristos  *    notice, this list of conditions and the following disclaimer.
12*37c9f0a6Schristos  * 2. Redistributions in binary form must reproduce the above copyright
13*37c9f0a6Schristos  *    notice, this list of conditions and the following disclaimer in the
14*37c9f0a6Schristos  *    documentation and/or other materials provided with the distribution.
15*37c9f0a6Schristos  * 3. Neither the name of the University nor the names of its contributors
16*37c9f0a6Schristos  *    may be used to endorse or promote products derived from this software
17*37c9f0a6Schristos  *    without specific prior written permission.
18*37c9f0a6Schristos  *
19*37c9f0a6Schristos  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20*37c9f0a6Schristos  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21*37c9f0a6Schristos  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22*37c9f0a6Schristos  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23*37c9f0a6Schristos  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24*37c9f0a6Schristos  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25*37c9f0a6Schristos  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26*37c9f0a6Schristos  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27*37c9f0a6Schristos  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28*37c9f0a6Schristos  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29*37c9f0a6Schristos  * SUCH DAMAGE.
30*37c9f0a6Schristos  */
31*37c9f0a6Schristos 
32*37c9f0a6Schristos #include <sys/cdefs.h>
33*37c9f0a6Schristos #if defined(LIBC_SCCS) && !defined(lint)
34*37c9f0a6Schristos #if 0
35*37c9f0a6Schristos static char sccsid[] = "@(#)strcasecmp.c	8.1 (Berkeley) 6/4/93";
36*37c9f0a6Schristos #else
37*37c9f0a6Schristos __RCSID("$NetBSD: strcasecmp.c,v 1.1 2005/12/20 19:28:52 christos Exp $");
38*37c9f0a6Schristos #endif
39*37c9f0a6Schristos #endif /* LIBC_SCCS and not lint */
40*37c9f0a6Schristos 
41*37c9f0a6Schristos #if !defined(_KERNEL) && !defined(_STANDALONE)
42*37c9f0a6Schristos #include "namespace.h"
43*37c9f0a6Schristos #include <assert.h>
44*37c9f0a6Schristos #include <ctype.h>
45*37c9f0a6Schristos #include <string.h>
46*37c9f0a6Schristos #ifdef __weak_alias
47*37c9f0a6Schristos __weak_alias(strcasecmp,_strcasecmp)
48*37c9f0a6Schristos __weak_alias(strncasecmp,_strncasecmp)
49*37c9f0a6Schristos #endif
50*37c9f0a6Schristos #else
51*37c9f0a6Schristos #include <lib/libkern/libkern.h>
52*37c9f0a6Schristos #include <machine/limits.h>
53*37c9f0a6Schristos #endif
54*37c9f0a6Schristos 
55*37c9f0a6Schristos int
56*37c9f0a6Schristos strcasecmp(s1, s2)
57*37c9f0a6Schristos 	const char *s1, *s2;
58*37c9f0a6Schristos {
59*37c9f0a6Schristos 	const unsigned char *us1 = (const unsigned char *)s1,
60*37c9f0a6Schristos 			*us2 = (const unsigned char *)s2;
61*37c9f0a6Schristos 
62*37c9f0a6Schristos 	_DIAGASSERT(s1 != NULL);
63*37c9f0a6Schristos 	_DIAGASSERT(s2 != NULL);
64*37c9f0a6Schristos 
65*37c9f0a6Schristos 	while (tolower(*us1) == tolower(*us2++))
66*37c9f0a6Schristos 		if (*us1++ == '\0')
67*37c9f0a6Schristos 			return (0);
68*37c9f0a6Schristos 	return (tolower(*us1) - tolower(*--us2));
69*37c9f0a6Schristos }
70