1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 * SPDX-License-Identifier: curl
22 *
23 ***************************************************************************/
24
25 #include "curl_setup.h"
26
27 #include <curl/curl.h>
28
29 #include "curl_memrchr.h"
30 #include "curl_memory.h"
31
32 /* The last #include file should be: */
33 #include "memdebug.h"
34
35 #ifndef HAVE_MEMRCHR
36 #if (!defined(CURL_DISABLE_HTTP) && !defined(CURL_DISABLE_COOKIES)) || \
37 defined(USE_OPENSSL) || \
38 defined(USE_SCHANNEL)
39
40 /*
41 * Curl_memrchr()
42 *
43 * Our memrchr() function clone for systems which lack this function. The
44 * memrchr() function is like the memchr() function, except that it searches
45 * backwards from the end of the n bytes pointed to by s instead of forward
46 * from the beginning.
47 */
48
49 void *
Curl_memrchr(const void * s,int c,size_t n)50 Curl_memrchr(const void *s, int c, size_t n)
51 {
52 if(n > 0) {
53 const unsigned char *p = s;
54 const unsigned char *q = s;
55
56 p += n - 1;
57
58 while(p >= q) {
59 if(*p == (unsigned char)c)
60 return (void *)p;
61 p--;
62 }
63 }
64 return NULL;
65 }
66
67 #endif
68 #endif /* HAVE_MEMRCHR */
69
