1*37c9f0a6Schristos /* $NetBSD: memchr.c,v 1.1 2005/12/20 19:28:52 christos Exp $ */ 2*37c9f0a6Schristos 3*37c9f0a6Schristos /*- 4*37c9f0a6Schristos * Copyright (c) 1990, 1993 5*37c9f0a6Schristos * The Regents of the University of California. All rights reserved. 6*37c9f0a6Schristos * 7*37c9f0a6Schristos * This code is derived from software contributed to Berkeley by 8*37c9f0a6Schristos * Chris Torek. 9*37c9f0a6Schristos * 10*37c9f0a6Schristos * Redistribution and use in source and binary forms, with or without 11*37c9f0a6Schristos * modification, are permitted provided that the following conditions 12*37c9f0a6Schristos * are met: 13*37c9f0a6Schristos * 1. Redistributions of source code must retain the above copyright 14*37c9f0a6Schristos * notice, this list of conditions and the following disclaimer. 15*37c9f0a6Schristos * 2. Redistributions in binary form must reproduce the above copyright 16*37c9f0a6Schristos * notice, this list of conditions and the following disclaimer in the 17*37c9f0a6Schristos * documentation and/or other materials provided with the distribution. 18*37c9f0a6Schristos * 3. Neither the name of the University nor the names of its contributors 19*37c9f0a6Schristos * may be used to endorse or promote products derived from this software 20*37c9f0a6Schristos * without specific prior written permission. 21*37c9f0a6Schristos * 22*37c9f0a6Schristos * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23*37c9f0a6Schristos * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24*37c9f0a6Schristos * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25*37c9f0a6Schristos * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26*37c9f0a6Schristos * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27*37c9f0a6Schristos * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28*37c9f0a6Schristos * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29*37c9f0a6Schristos * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30*37c9f0a6Schristos * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31*37c9f0a6Schristos * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32*37c9f0a6Schristos * SUCH DAMAGE. 33*37c9f0a6Schristos */ 34*37c9f0a6Schristos 35*37c9f0a6Schristos #include <sys/cdefs.h> 36*37c9f0a6Schristos #if defined(LIBC_SCCS) && !defined(lint) 37*37c9f0a6Schristos #if 0 38*37c9f0a6Schristos static char sccsid[] = "@(#)memchr.c 8.1 (Berkeley) 6/4/93"; 39*37c9f0a6Schristos #else 40*37c9f0a6Schristos __RCSID("$NetBSD: memchr.c,v 1.1 2005/12/20 19:28:52 christos Exp $"); 41*37c9f0a6Schristos #endif 42*37c9f0a6Schristos #endif /* LIBC_SCCS and not lint */ 43*37c9f0a6Schristos 44*37c9f0a6Schristos #if !defined(_KERNEL) && !defined(_STANDALONE) 45*37c9f0a6Schristos #include <assert.h> 46*37c9f0a6Schristos #include <string.h> 47*37c9f0a6Schristos #else 48*37c9f0a6Schristos #include <lib/libkern/libkern.h> 49*37c9f0a6Schristos #endif 50*37c9f0a6Schristos 51*37c9f0a6Schristos void * 52*37c9f0a6Schristos memchr(s, c, n) 53*37c9f0a6Schristos const void *s; 54*37c9f0a6Schristos unsigned char c; 55*37c9f0a6Schristos size_t n; 56*37c9f0a6Schristos { 57*37c9f0a6Schristos _DIAGASSERT(s != NULL); 58*37c9f0a6Schristos 59*37c9f0a6Schristos if (n != 0) { 60*37c9f0a6Schristos const unsigned char *p = s; 61*37c9f0a6Schristos 62*37c9f0a6Schristos do { 63*37c9f0a6Schristos if (*p++ == c) 64*37c9f0a6Schristos return __UNCONST(p - 1); 65*37c9f0a6Schristos } while (--n != 0); 66*37c9f0a6Schristos } 67*37c9f0a6Schristos return NULL; 68*37c9f0a6Schristos } 69