1 /*
2 * This file and its contents are supplied under the terms of the
3 * Common Development and Distribution License ("CDDL"), version 1.0.
4 * You may only use this file in accordance with the terms of version
5 * 1.0 of the CDDL.
6 *
7 * A full copy of the text of the CDDL should have accompanied this
8 * source. A copy of the CDDL is also available via the Internet at
9 * http://www.illumos.org/license/CDDL.
10 */
11
12 /*
13 * Copyright 2021 Oxide Computer Company
14 */
15
16 /*
17 * memrchr(3C) implementation. Find the first occurence of 'c' as an unsigned
18 * char in 's', by searching in reverse.
19 */
20
21 #include <string.h>
22
23 void *
memrchr(const void * s,int c,size_t len)24 memrchr(const void *s, int c, size_t len)
25 {
26 unsigned char val = (unsigned char)c;
27 const unsigned char *data = s;
28
29 for (; len > 0; len--) {
30 size_t pos = len - 1;
31
32 if (data[pos] == val) {
33 return ((void *)&data[pos]);
34 }
35 }
36
37 return (NULL);
38 }
39