xref: /netbsd-src/lib/libc/string/wmemcmp.c (revision 9e66e6d75e9910b3de5f4ef031995955f69a7dd1)

/*	$NetBSD: wmemcmp.c,v 1.7 2012/06/25 22:32:46 abs Exp $	*/

/*-
 * Copyright (c)1999 Citrus Project,
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	citrus Id: wmemcmp.c,v 1.2 2000/12/20 14:08:31 itojun Exp
 */

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: wmemcmp.c,v 1.7 2012/06/25 22:32:46 abs Exp $");
#endif /* LIBC_SCCS and not lint */

#include <assert.h>
#include <wchar.h>
#include "runetype_local.h"

int
wmemcmp(const wchar_t *s1, const wchar_t *s2, size_t n)
{
	size_t i;

	_DIAGASSERT(s1 != NULL);
	_DIAGASSERT(s2 != NULL);

	for (i = 0; i < n; i++) {
		if (*s1 != *s2) {
			/* wchar might be unsigned */
			return *(const __nbrune_t *)s1 >
			       *(const __nbrune_t *)s2 ? 1 : -1;
		}
		s1++;
		s2++;
	}
	return 0;
}