xref: /illumos-gate/usr/src/common/util/memchr.c (revision 7c478bd9)
1*7c478bd9Sstevel@tonic-gate /*
2*7c478bd9Sstevel@tonic-gate  * CDDL HEADER START
3*7c478bd9Sstevel@tonic-gate  *
4*7c478bd9Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*7c478bd9Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*7c478bd9Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*7c478bd9Sstevel@tonic-gate  * with the License.
8*7c478bd9Sstevel@tonic-gate  *
9*7c478bd9Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*7c478bd9Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*7c478bd9Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*7c478bd9Sstevel@tonic-gate  * and limitations under the License.
13*7c478bd9Sstevel@tonic-gate  *
14*7c478bd9Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*7c478bd9Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*7c478bd9Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*7c478bd9Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*7c478bd9Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*7c478bd9Sstevel@tonic-gate  *
20*7c478bd9Sstevel@tonic-gate  * CDDL HEADER END
21*7c478bd9Sstevel@tonic-gate  */
22*7c478bd9Sstevel@tonic-gate /*
23*7c478bd9Sstevel@tonic-gate  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24*7c478bd9Sstevel@tonic-gate  * Use is subject to license terms.
25*7c478bd9Sstevel@tonic-gate  */
26*7c478bd9Sstevel@tonic-gate 
27*7c478bd9Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
28*7c478bd9Sstevel@tonic-gate 
29*7c478bd9Sstevel@tonic-gate /*	Copyright (c) 1988 AT&T	*/
30*7c478bd9Sstevel@tonic-gate /*	  All Rights Reserved  	*/
31*7c478bd9Sstevel@tonic-gate 
32*7c478bd9Sstevel@tonic-gate 
33*7c478bd9Sstevel@tonic-gate #include <sys/types.h>
34*7c478bd9Sstevel@tonic-gate #if defined(_KERNEL)
35*7c478bd9Sstevel@tonic-gate #include <sys/systm.h>
36*7c478bd9Sstevel@tonic-gate #else
37*7c478bd9Sstevel@tonic-gate #include <string.h>
38*7c478bd9Sstevel@tonic-gate #include <stddef.h>
39*7c478bd9Sstevel@tonic-gate #endif
40*7c478bd9Sstevel@tonic-gate 
41*7c478bd9Sstevel@tonic-gate /*
42*7c478bd9Sstevel@tonic-gate  * Return the ptr in sptr at which the character c1 appears;
43*7c478bd9Sstevel@tonic-gate  * or NULL if not found in n chars; don't stop at \0.
44*7c478bd9Sstevel@tonic-gate  */
45*7c478bd9Sstevel@tonic-gate void *
memchr(const void * sptr,int c1,size_t n)46*7c478bd9Sstevel@tonic-gate memchr(const void *sptr, int c1, size_t n)
47*7c478bd9Sstevel@tonic-gate {
48*7c478bd9Sstevel@tonic-gate 	if (n != 0) {
49*7c478bd9Sstevel@tonic-gate 		unsigned char c = (unsigned char)c1;
50*7c478bd9Sstevel@tonic-gate 		const unsigned char *sp = sptr;
51*7c478bd9Sstevel@tonic-gate 
52*7c478bd9Sstevel@tonic-gate 		do {
53*7c478bd9Sstevel@tonic-gate 			if (*sp++ == c)
54*7c478bd9Sstevel@tonic-gate 				return ((void *)--sp);
55*7c478bd9Sstevel@tonic-gate 		} while (--n != 0);
56*7c478bd9Sstevel@tonic-gate 	}
57*7c478bd9Sstevel@tonic-gate 	return (NULL);
58*7c478bd9Sstevel@tonic-gate }
59