1  /*-
 2   * Copyright (c) 1990, 1993
 3   *	The Regents of the University of California.  All rights reserved.
 4   *
 5   * This code is derived from software contributed to Berkeley by
 6   * Chris Torek.
 7   *
 8   * Redistribution and use in source and binary forms, with or without
 9   * modification, are permitted provided that the following conditions
10   * are met:
11   * 1. Redistributions of source code must retain the above copyright
12   *    notice, this list of conditions and the following disclaimer.
13   * 2. Redistributions in binary form must reproduce the above copyright
14   *    notice, this list of conditions and the following disclaimer in the
15   *    documentation and/or other materials provided with the distribution.
16   * 4. Neither the name of the University nor the names of its contributors
17   *    may be used to endorse or promote products derived from this software
18   *    without specific prior written permission.
19   *
20   * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23   * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30   * SUCH DAMAGE.
31   */
32  
33  #if 0
34  #if defined(LIBC_SCCS) && !defined(lint)
35  static char sccsid[] = "@(#)strstr.c	8.1 (Berkeley) 6/4/93";
36  #endif /* LIBC_SCCS and not lint */
37  #endif
38  #include <sys/cdefs.h>
39  __FBSDID("$FreeBSD: src/lib/libc/string/wcsstr.c,v 1.10 2009/02/03 17:58:20 danger Exp $");
40  
41  #include <wchar.h>
42  
43  /*
44   * Find the first occurrence of find in s.
45   */
46  wchar_t *
47  wcsstr(const wchar_t * __restrict s, const wchar_t * __restrict find)
48  {
49  	wchar_t c, sc;
50  	size_t len;
51  
52  	if ((c = *find++) != L'\0') {
53  		len = wcslen(find);
54  		do {
55  			do {
56  				if ((sc = *s++) == L'\0')
57  					return (NULL);
58  			} while (sc != c);
59  		} while (wcsncmp(s, find, len) != 0);
60  		s--;
61  	}
62  	return ((wchar_t *)s);
63  }