xref: /freebsd/lib/libc/string/wcsncmp.c (revision 9336e0699bda8a301cd2bfa37106b6ec5e32012e)
1 /*
2  * Copyright (c) 1989, 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  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 #if 0
32 #if defined(LIBC_SCCS) && !defined(lint)
33 static char sccsid[] = "@(#)strncmp.c	8.1 (Berkeley) 6/4/93";
34 __RCSID("$NetBSD: wcsncmp.c,v 1.3 2001/01/05 12:13:13 itojun Exp $");
35 #endif /* LIBC_SCCS and not lint */
36 #endif
37 __FBSDID("$FreeBSD$");
38 
39 #include <wchar.h>
40 
41 int
42 wcsncmp(s1, s2, n)
43 	const wchar_t *s1, *s2;
44 	size_t n;
45 {
46 
47 	if (n == 0)
48 		return (0);
49 	do {
50 		if (*s1 != *s2++) {
51 			/* XXX assumes wchar_t = int */
52 			return (*(const unsigned int *)s1 -
53 			    *(const unsigned int *)--s2);
54 		}
55 		if (*s1++ == 0)
56 			break;
57 	} while (--n != 0);
58 	return (0);
59 }
60