xref: /netbsd-src/common/lib/libc/string/strrchr.c (revision a6a8f0073da6f13a9bf3354e3e4fa8e5e187a360)
1*a6a8f007Sskrll /*	$NetBSD: strrchr.c,v 1.7 2020/04/07 08:07:58 skrll Exp $	*/
237c9f0a6Schristos 
337c9f0a6Schristos /*
437c9f0a6Schristos  * Copyright (c) 1988, 1993
537c9f0a6Schristos  *	The Regents of the University of California.  All rights reserved.
637c9f0a6Schristos  *
737c9f0a6Schristos  * Redistribution and use in source and binary forms, with or without
837c9f0a6Schristos  * modification, are permitted provided that the following conditions
937c9f0a6Schristos  * are met:
1037c9f0a6Schristos  * 1. Redistributions of source code must retain the above copyright
1137c9f0a6Schristos  *    notice, this list of conditions and the following disclaimer.
1237c9f0a6Schristos  * 2. Redistributions in binary form must reproduce the above copyright
1337c9f0a6Schristos  *    notice, this list of conditions and the following disclaimer in the
1437c9f0a6Schristos  *    documentation and/or other materials provided with the distribution.
1537c9f0a6Schristos  * 3. Neither the name of the University nor the names of its contributors
1637c9f0a6Schristos  *    may be used to endorse or promote products derived from this software
1737c9f0a6Schristos  *    without specific prior written permission.
1837c9f0a6Schristos  *
1937c9f0a6Schristos  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
2037c9f0a6Schristos  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
2137c9f0a6Schristos  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
2237c9f0a6Schristos  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
2337c9f0a6Schristos  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
2437c9f0a6Schristos  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2537c9f0a6Schristos  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
2637c9f0a6Schristos  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
2737c9f0a6Schristos  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
2837c9f0a6Schristos  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
2937c9f0a6Schristos  * SUCH DAMAGE.
3037c9f0a6Schristos  */
3137c9f0a6Schristos 
3237c9f0a6Schristos #include <sys/cdefs.h>
3337c9f0a6Schristos #if defined(LIBC_SCCS) && !defined(lint)
3437c9f0a6Schristos #if 0
3537c9f0a6Schristos static char sccsid[] = "@(#)rindex.c	8.1 (Berkeley) 6/4/93";
3637c9f0a6Schristos #else
37*a6a8f007Sskrll __RCSID("$NetBSD: strrchr.c,v 1.7 2020/04/07 08:07:58 skrll Exp $");
3837c9f0a6Schristos #endif
3937c9f0a6Schristos #endif /* LIBC_SCCS and not lint */
4037c9f0a6Schristos 
4137c9f0a6Schristos #if !defined(_KERNEL) && !defined(_STANDALONE)
4237c9f0a6Schristos #include <assert.h>
4337c9f0a6Schristos #include <string.h>
4437c9f0a6Schristos #else
4537c9f0a6Schristos #include <lib/libkern/libkern.h>
4637c9f0a6Schristos #endif
4737c9f0a6Schristos 
48*a6a8f007Sskrll #if defined(KASAN)
49*a6a8f007Sskrll #undef strrchr
50*a6a8f007Sskrll #endif
51*a6a8f007Sskrll 
__strong_alias(rindex,strrchr)5253a0f227Sdsl __strong_alias(rindex, strrchr)
5337c9f0a6Schristos char *
54a8565cf9Schristos strrchr(const char *p, int ch)
5537c9f0a6Schristos {
56ececdb79Smartin 	char *save;
57ececdb79Smartin 	const char c = ch;
5837c9f0a6Schristos 
5937c9f0a6Schristos 	for (save = NULL;; ++p) {
60d5e6ed89Smartin 		if (*p == c) {
6137c9f0a6Schristos 			/* LINTED const cast-away */
6237c9f0a6Schristos 			save = __UNCONST(p);
6337c9f0a6Schristos 		}
6437c9f0a6Schristos 		if (!*p)
6537c9f0a6Schristos 			return(save);
6637c9f0a6Schristos 	}
6737c9f0a6Schristos 	/* NOTREACHED */
6837c9f0a6Schristos }
69