xref: /minix3/common/lib/libc/string/strchr.c (revision f14fb602092e015ff630df58e17c2a9cd57d29b3)
1*f14fb602SLionel Sambuc /*	$NetBSD: strchr.c,v 1.5 2011/08/31 15:48:32 plunky Exp $	*/
2b6cbf720SGianluca Guida 
3b6cbf720SGianluca Guida /*-
4b6cbf720SGianluca Guida  * Copyright (c) 1990, 1993
5b6cbf720SGianluca Guida  *	The Regents of the University of California.  All rights reserved.
6b6cbf720SGianluca Guida  *
7b6cbf720SGianluca Guida  * Redistribution and use in source and binary forms, with or without
8b6cbf720SGianluca Guida  * modification, are permitted provided that the following conditions
9b6cbf720SGianluca Guida  * are met:
10b6cbf720SGianluca Guida  * 1. Redistributions of source code must retain the above copyright
11b6cbf720SGianluca Guida  *    notice, this list of conditions and the following disclaimer.
12b6cbf720SGianluca Guida  * 2. Redistributions in binary form must reproduce the above copyright
13b6cbf720SGianluca Guida  *    notice, this list of conditions and the following disclaimer in the
14b6cbf720SGianluca Guida  *    documentation and/or other materials provided with the distribution.
15b6cbf720SGianluca Guida  * 3. Neither the name of the University nor the names of its contributors
16b6cbf720SGianluca Guida  *    may be used to endorse or promote products derived from this software
17b6cbf720SGianluca Guida  *    without specific prior written permission.
18b6cbf720SGianluca Guida  *
19b6cbf720SGianluca Guida  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20b6cbf720SGianluca Guida  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21b6cbf720SGianluca Guida  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22b6cbf720SGianluca Guida  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23b6cbf720SGianluca Guida  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24b6cbf720SGianluca Guida  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25b6cbf720SGianluca Guida  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26b6cbf720SGianluca Guida  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27b6cbf720SGianluca Guida  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28b6cbf720SGianluca Guida  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29b6cbf720SGianluca Guida  * SUCH DAMAGE.
30b6cbf720SGianluca Guida  */
31b6cbf720SGianluca Guida 
32b6cbf720SGianluca Guida #include <sys/cdefs.h>
33b6cbf720SGianluca Guida #if defined(LIBC_SCCS) && !defined(lint)
34b6cbf720SGianluca Guida #if 0
35b6cbf720SGianluca Guida static char sccsid[] = "@(#)index.c	8.1 (Berkeley) 6/4/93";
36b6cbf720SGianluca Guida #else
37*f14fb602SLionel Sambuc __RCSID("$NetBSD: strchr.c,v 1.5 2011/08/31 15:48:32 plunky Exp $");
38b6cbf720SGianluca Guida #endif
39b6cbf720SGianluca Guida #endif /* LIBC_SCCS and not lint */
40b6cbf720SGianluca Guida 
41b6cbf720SGianluca Guida #if !defined(_KERNEL) && !defined(_STANDALONE)
42b6cbf720SGianluca Guida #include "namespace.h"
43b6cbf720SGianluca Guida #include <assert.h>
44b6cbf720SGianluca Guida #include <string.h>
45b6cbf720SGianluca Guida #else
46b6cbf720SGianluca Guida #include <lib/libkern/libkern.h>
47b6cbf720SGianluca Guida #endif
48b6cbf720SGianluca Guida 
__strong_alias(index,strchr)49b6cbf720SGianluca Guida __strong_alias(index, strchr)
50b6cbf720SGianluca Guida char *
51b6cbf720SGianluca Guida strchr(const char *p, int ch)
52b6cbf720SGianluca Guida {
53b6cbf720SGianluca Guida 	const char cmp = ch;
54b6cbf720SGianluca Guida 	_DIAGASSERT(p != NULL);
55b6cbf720SGianluca Guida 
56b6cbf720SGianluca Guida 	for (;; ++p) {
57b6cbf720SGianluca Guida 		if (*p == cmp) {
58b6cbf720SGianluca Guida 			/* LINTED const cast-away */
59b6cbf720SGianluca Guida 			return(__UNCONST(p));
60b6cbf720SGianluca Guida 		}
61b6cbf720SGianluca Guida 		if (!*p)
62*f14fb602SLionel Sambuc 			return(NULL);
63b6cbf720SGianluca Guida 	}
64b6cbf720SGianluca Guida 	/* NOTREACHED */
65b6cbf720SGianluca Guida }
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