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      1 /*	$NetBSD: wcsstr.c,v 1.5 2012/06/25 22:32:46 abs Exp $	*/
      2 
      3 /*-
      4  * Copyright (c)1999 Citrus Project,
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     26  * SUCH DAMAGE.
     27  *
     28  *	citrus Id: wcsstr.c,v 1.2 2000/12/21 05:07:25 itojun Exp
     29  */
     30 
     31 #include <sys/cdefs.h>
     32 #if defined(LIBC_SCCS) && !defined(lint)
     33 __RCSID("$NetBSD: wcsstr.c,v 1.5 2012/06/25 22:32:46 abs Exp $");
     34 #endif /* LIBC_SCCS and not lint */
     35 
     36 #include <assert.h>
     37 #include <wchar.h>
     38 
     39 wchar_t *
     40 #ifdef WCSWCS
     41 wcswcs(const wchar_t *big, const wchar_t *little)
     42 #else
     43 wcsstr(const wchar_t *big, const wchar_t *little)
     44 #endif
     45 {
     46 	const wchar_t *p;
     47 	const wchar_t *q;
     48 	const wchar_t *r;
     49 
     50 	_DIAGASSERT(big != NULL);
     51 	_DIAGASSERT(little != NULL);
     52 
     53 	if (!*little)
     54 		return __UNCONST(big);
     55 	if (wcslen(big) < wcslen(little))
     56 		return NULL;
     57 
     58 	p = big;
     59 	q = little;
     60 	while (*p) {
     61 		q = little;
     62 		r = p;
     63 		while (*q) {
     64 			if (*r != *q)
     65 				break;
     66 			q++;
     67 			r++;
     68 		}
     69 		if (!*q)
     70 			return __UNCONST(p);
     71 		p++;
     72 	}
     73 	return NULL;
     74 }
     75