xref: /freebsd/lib/libc/string/wcsncmp.c (revision 7773002178c8dbc52b44e4d705f07706409af8e4)
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  * 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 #include <sys/cdefs.h>
35 #if 0
36 #if defined(LIBC_SCCS) && !defined(lint)
37 static char sccsid[] = "@(#)strncmp.c	8.1 (Berkeley) 6/4/93";
38 __RCSID("$NetBSD: wcsncmp.c,v 1.3 2001/01/05 12:13:13 itojun Exp $");
39 #endif /* LIBC_SCCS and not lint */
40 #endif
41 __FBSDID("$FreeBSD$");
42 
43 #include <wchar.h>
44 
45 int
46 wcsncmp(s1, s2, n)
47 	const wchar_t *s1, *s2;
48 	size_t n;
49 {
50 
51 	if (n == 0)
52 		return (0);
53 	do {
54 		if (*s1 != *s2++) {
55 			/* XXX assumes wchar_t = int */
56 			return (*(const unsigned int *)s1 -
57 			    *(const unsigned int *)--s2);
58 		}
59 		if (*s1++ == 0)
60 			break;
61 	} while (--n != 0);
62 	return (0);
63 }
64