xref: /netbsd-src/lib/libc/string/wcsstr.c (revision 9e66e6d75e9910b3de5f4ef031995955f69a7dd1)
1*9e66e6d7Sabs /*	$NetBSD: wcsstr.c,v 1.5 2012/06/25 22:32:46 abs Exp $	*/
2383f218aSitojun 
3383f218aSitojun /*-
4383f218aSitojun  * Copyright (c)1999 Citrus Project,
5383f218aSitojun  * All rights reserved.
6383f218aSitojun  *
7383f218aSitojun  * Redistribution and use in source and binary forms, with or without
8383f218aSitojun  * modification, are permitted provided that the following conditions
9383f218aSitojun  * are met:
10383f218aSitojun  * 1. Redistributions of source code must retain the above copyright
11383f218aSitojun  *    notice, this list of conditions and the following disclaimer.
12383f218aSitojun  * 2. Redistributions in binary form must reproduce the above copyright
13383f218aSitojun  *    notice, this list of conditions and the following disclaimer in the
14383f218aSitojun  *    documentation and/or other materials provided with the distribution.
15383f218aSitojun  *
16383f218aSitojun  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17383f218aSitojun  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18383f218aSitojun  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19383f218aSitojun  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20383f218aSitojun  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21383f218aSitojun  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22383f218aSitojun  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23383f218aSitojun  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24383f218aSitojun  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25383f218aSitojun  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26383f218aSitojun  * SUCH DAMAGE.
27383f218aSitojun  *
28383f218aSitojun  *	citrus Id: wcsstr.c,v 1.2 2000/12/21 05:07:25 itojun Exp
29383f218aSitojun  */
30383f218aSitojun 
31383f218aSitojun #include <sys/cdefs.h>
32383f218aSitojun #if defined(LIBC_SCCS) && !defined(lint)
33*9e66e6d7Sabs __RCSID("$NetBSD: wcsstr.c,v 1.5 2012/06/25 22:32:46 abs Exp $");
34383f218aSitojun #endif /* LIBC_SCCS and not lint */
35383f218aSitojun 
365ba790cbSlukem #include <assert.h>
37383f218aSitojun #include <wchar.h>
38383f218aSitojun 
39383f218aSitojun wchar_t *
40326ed368Stshiozak #ifdef WCSWCS
wcswcs(const wchar_t * big,const wchar_t * little)41*9e66e6d7Sabs wcswcs(const wchar_t *big, const wchar_t *little)
42326ed368Stshiozak #else
43*9e66e6d7Sabs wcsstr(const wchar_t *big, const wchar_t *little)
44326ed368Stshiozak #endif
45383f218aSitojun {
46383f218aSitojun 	const wchar_t *p;
47383f218aSitojun 	const wchar_t *q;
48383f218aSitojun 	const wchar_t *r;
49383f218aSitojun 
505ba790cbSlukem 	_DIAGASSERT(big != NULL);
515ba790cbSlukem 	_DIAGASSERT(little != NULL);
525ba790cbSlukem 
5303256c6eSchristos 	if (!*little)
5403256c6eSchristos 		return __UNCONST(big);
55383f218aSitojun 	if (wcslen(big) < wcslen(little))
56383f218aSitojun 		return NULL;
57383f218aSitojun 
58383f218aSitojun 	p = big;
59383f218aSitojun 	q = little;
60383f218aSitojun 	while (*p) {
61383f218aSitojun 		q = little;
62383f218aSitojun 		r = p;
63383f218aSitojun 		while (*q) {
64383f218aSitojun 			if (*r != *q)
65383f218aSitojun 				break;
66383f218aSitojun 			q++;
67383f218aSitojun 			r++;
68383f218aSitojun 		}
6903256c6eSchristos 		if (!*q)
7003256c6eSchristos 			return __UNCONST(p);
71383f218aSitojun 		p++;
72383f218aSitojun 	}
73383f218aSitojun 	return NULL;
74383f218aSitojun }
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