xref: /illumos-gate/usr/src/lib/libc/port/i18n/wcsstr.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include "lint.h"
30 #include <sys/types.h>
31 #include <wchar.h>
32 #include "libc.h"
33 
34 wchar_t *
35 wcsstr(const wchar_t *ws1, const wchar_t *ws2)
36 {
37 	const wchar_t	*os1, *os2;
38 	const wchar_t	*tptr;
39 	wchar_t	c;
40 
41 	os1 = ws1;
42 	os2 = ws2;
43 
44 	if (os1 == NULL || *os2 == L'\0')
45 		return ((wchar_t *)os1);
46 	c = *os2;
47 
48 	while (*os1)
49 		if (*os1++ == c) {
50 			tptr = os1;
51 			while (((c = *++os2) == *os1++) && (c != L'\0'))
52 				;
53 			if (c == L'\0')
54 				return ((wchar_t *)tptr - 1);
55 			os1 = tptr;
56 			os2 = ws2;
57 			c = *os2;
58 		}
59 	return (NULL);
60 }
61