67 lines
2.3 KiB
C
67 lines
2.3 KiB
C
|
/* $NetBSD: memchr.c,v 1.3 2008/01/08 21:57:06 martin Exp $ */
|
||
|
|
||
|
/*-
|
||
|
* Copyright (c) 1990, 1993
|
||
|
* The Regents of the University of California. All rights reserved.
|
||
|
*
|
||
|
* This code is derived from software contributed to Berkeley by
|
||
|
* Chris Torek.
|
||
|
*
|
||
|
* 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.
|
||
|
* 3. Neither the name of the University nor the names of its contributors
|
||
|
* may be used to endorse or promote products derived from this software
|
||
|
* without specific prior written permission.
|
||
|
*
|
||
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
|
||
|
*/
|
||
|
|
||
|
#include <sys/cdefs.h>
|
||
|
#if defined(LIBC_SCCS) && !defined(lint)
|
||
|
#if 0
|
||
|
static char sccsid[] = "@(#)memchr.c 8.1 (Berkeley) 6/4/93";
|
||
|
#else
|
||
|
__RCSID("$NetBSD: memchr.c,v 1.3 2008/01/08 21:57:06 martin Exp $");
|
||
|
#endif
|
||
|
#endif /* LIBC_SCCS and not lint */
|
||
|
|
||
|
#if !defined(_KERNEL) && !defined(_STANDALONE)
|
||
|
#include <assert.h>
|
||
|
#include <string.h>
|
||
|
#else
|
||
|
#include <lib/libkern/libkern.h>
|
||
|
#endif
|
||
|
|
||
|
void *
|
||
|
memchr(const void *s, int c, size_t n)
|
||
|
{
|
||
|
_DIAGASSERT(s != NULL);
|
||
|
|
||
|
if (n != 0) {
|
||
|
const unsigned char *p = s;
|
||
|
const unsigned char cmp = c;
|
||
|
|
||
|
do {
|
||
|
if (*p++ == cmp)
|
||
|
return __UNCONST(p - 1);
|
||
|
} while (--n != 0);
|
||
|
}
|
||
|
return NULL;
|
||
|
}
|