1 /* $OpenBSD: memrchr.c,v 1.2 2007/11/27 16:22:12 martynas Exp $ */
2
3 /*
4 * Copyright (c) 2007 Todd C. Miller <Todd.Miller@courtesan.com>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19 #include <string.h>
20
21 /*
22 * Reverse memchr()
23 * Find the last occurrence of 'c' in the buffer 's' of size 'n'.
24 */
25 void *
memrchr(const void * s,int c,size_t n)26 memrchr(const void *s, int c, size_t n)
27 {
28 const unsigned char *cp;
29
30 if (n != 0) {
31 cp = (unsigned char *)s + n;
32 do {
33 if (*(--cp) == (unsigned char)c)
34 return((void *)cp);
35 } while (--n != 0);
36 }
37 return(NULL);
38 }
39