xref: /illumos-gate/usr/src/common/util/memchr.c (revision 012e6ce759c490003aed29439cc47d3d73a99ad3)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1988 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 
31 #include <sys/types.h>
32 #if defined(_KERNEL)
33 #include <sys/systm.h>
34 #else
35 #include <string.h>
36 #include <stddef.h>
37 #endif
38 
39 /*
40  * Return the ptr in sptr at which the character c1 appears;
41  * or NULL if not found in n chars; don't stop at \0.
42  */
43 void *
44 memchr(const void *sptr, int c1, size_t n)
45 {
46 	if (n != 0) {
47 		unsigned char c = (unsigned char)c1;
48 		const unsigned char *sp = sptr;
49 
50 		do {
51 			if (*sp++ == c)
52 				return ((void *)--sp);
53 		} while (--n != 0);
54 	}
55 	return (NULL);
56 }
57