memchr.c revision 1.2 
1/*	$OpenBSD: memchr.c,v 1.2 1998/06/27 01:21:03 mickey Exp $	*/
2
3/*-
4 * Copyright (c) 1990 The Regents of the University of California.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Chris Torek.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *	This product includes software developed by the University of
21 *	California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 *    may be used to endorse or promote products derived from this software
24 *    without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 */
38
39#if defined(LIBC_SCCS) && !defined(lint)
40/*static char *sccsid = "from: @(#)memchr.c     5.6 (Berkeley) 1/26/91";*/
41static char *rcsid = "$NetBSD: memchr.c,v 1.2 1997/10/24 18:10:30 mjacob Exp $";
42#endif /* LIBC_SCCS and not lint */
43
44#if !defined(_KERNEL) && !defined(_STANDALONE)
45#include <string.h>
46#else
47#include <lib/libkern/libkern.h>
48#define	NULL	((char *)0)
49#endif
50
51void *
52memchr(s, c, n)
53	const void *s;
54	register unsigned char c;
55	register size_t n;
56{
57	if (n != 0) {
58		register const unsigned char *p = s;
59
60		do {
61			if (*p++ == c)
62				return ((void *)(p - 1));
63		} while (--n != 0);
64	}
65	return (NULL);
66}
67