xref: /freebsd/crypto/openssh/openbsd-compat/strcasestr.c (revision 5f4c09dd85bff675e0ca63c55ea3c517e0fddfcc)
1 /*	$OpenBSD: strcasestr.c,v 1.4 2015/08/31 02:53:57 guenther Exp $	*/
2 /*	$NetBSD: strcasestr.c,v 1.2 2005/02/09 21:35:47 kleink Exp $	*/
3 
4 /*-
5  * Copyright (c) 1990, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Chris Torek.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 /* OPENBSD ORIGINAL: lib/libc/string/strcasestr.c */
37 
38 #include "includes.h"
39 
40 #ifndef HAVE_STRCASESTR
41 
42 #include <ctype.h>
43 #include <string.h>
44 
45 /*
46  * Find the first occurrence of find in s, ignore case.
47  */
48 char *
49 strcasestr(const char *s, const char *find)
50 {
51 	char c, sc;
52 	size_t len;
53 
54 	if ((c = *find++) != 0) {
55 		c = (char)tolower((unsigned char)c);
56 		len = strlen(find);
57 		do {
58 			do {
59 				if ((sc = *s++) == 0)
60 					return (NULL);
61 			} while ((char)tolower((unsigned char)sc) != c);
62 		} while (strncasecmp(s, find, len) != 0);
63 		s--;
64 	}
65 	return ((char *)s);
66 }
67 DEF_WEAK(strcasestr);
68 
69 #endif
70