xref: /freebsd/contrib/mandoc/compat_strcasestr.c (revision f6a3b357e9be4c6423c85eff9a847163a0d307c8)
1 #include "config.h"
2 
3 #if HAVE_STRCASESTR
4 
5 int dummy;
6 
7 #else
8 
9 /*	$Id: compat_strcasestr.c,v 1.4 2014/12/11 09:19:32 schwarze Exp $	*/
10 /*	$NetBSD: strcasestr.c,v 1.3 2005/11/29 03:12:00 christos Exp $	*/
11 
12 /*-
13  * Copyright (c) 1990, 1993
14  *	The Regents of the University of California.  All rights reserved.
15  *
16  * This code is derived from software contributed to Berkeley by
17  * Chris Torek.
18  *
19  * Redistribution and use in source and binary forms, with or without
20  * modification, are permitted provided that the following conditions
21  * are met:
22  * 1. Redistributions of source code must retain the above copyright
23  *    notice, this list of conditions and the following disclaimer.
24  * 2. Redistributions in binary form must reproduce the above copyright
25  *    notice, this list of conditions and the following disclaimer in the
26  *    documentation and/or other materials provided with the distribution.
27  * 3. Neither the name of the University nor the names of its contributors
28  *    may be used to endorse or promote products derived from this software
29  *    without specific prior written permission.
30  *
31  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
32  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
33  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
34  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
35  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
39  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
40  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
41  * SUCH DAMAGE.
42  */
43 
44 #include <sys/types.h>
45 #include <ctype.h>
46 #include <string.h>
47 
48 #define	__UNCONST(a)	((void *)(unsigned long)(const void *)(a))
49 
50 /*
51  * Find the first occurrence of find in s, ignore case.
52  */
53 char *
54 strcasestr(const char *s, const char *find)
55 {
56 	char c, sc;
57 	size_t len;
58 
59 	if ((c = *find++) != 0) {
60 		c = tolower((unsigned char)c);
61 		len = strlen(find);
62 		do {
63 			do {
64 				if ((sc = *s++) == 0)
65 					return (NULL);
66 			} while ((char)tolower((unsigned char)sc) != c);
67 		} while (strncasecmp(s, find, len) != 0);
68 		s--;
69 	}
70 	return __UNCONST(s);
71 }
72 
73 #endif
74