1 /* $OpenBSD: memchr.c,v 1.3 2003/06/02 23:28:08 millert 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. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #if defined(LIBC_SCCS) && !defined(lint) 36 /*static char *sccsid = "from: @(#)memchr.c 5.6 (Berkeley) 1/26/91";*/ 37 static char *rcsid = "$NetBSD: memchr.c,v 1.2 1997/10/24 18:10:30 mjacob Exp $"; 38 #endif /* LIBC_SCCS and not lint */ 39 40 #if !defined(_KERNEL) && !defined(_STANDALONE) 41 #include <string.h> 42 #else 43 #include <lib/libkern/libkern.h> 44 #define NULL ((char *)0) 45 #endif 46 47 void * 48 memchr(s, c, n) 49 const void *s; 50 register unsigned char c; 51 register size_t n; 52 { 53 if (n != 0) { 54 register const unsigned char *p = s; 55 56 do { 57 if (*p++ == c) 58 return ((void *)(p - 1)); 59 } while (--n != 0); 60 } 61 return (NULL); 62 } 63