1 /*
2 FUNCTION
3 <<wcsstr>>---find a wide-character substring
4
5 SYNOPSIS
6 #include <wchar.h>
7 wchar_t *wcsstr(const wchar_t *__restrict <[big]>,
8 const wchar_t *__restrict <[little]>);
9
10 DESCRIPTION
11 The <<wcsstr>> function locates the first occurrence in the
12 wide-character string pointed to by <[big]> of the sequence of
13 wide characters (excluding the terminating null wide character) in the
14 wide-character string pointed to by <[little]>.
15
16 RETURNS
17 On successful completion, <<wcsstr>> returns a pointer to the located
18 wide-character string, or a null pointer if the wide-character string
19 is not found.
20
21 If <[little]> points to a wide-character string with zero length,
22 the function returns <[big]>.
23
24 PORTABILITY
25 <<wcsstr>> is ISO/IEC 9899/AMD1:1995 (ISO C).
26
27 */
28
29 /* $NetBSD: wcsstr.c,v 1.1 2000/12/23 23:14:37 itojun Exp $ */
30
31 /*-
32 * Copyright (c)1999 Citrus Project,
33 * All rights reserved.
34 *
35 * Redistribution and use in source and binary forms, with or without
36 * modification, are permitted provided that the following conditions
37 * are met:
38 * 1. Redistributions of source code must retain the above copyright
39 * notice, this list of conditions and the following disclaimer.
40 * 2. Redistributions in binary form must reproduce the above copyright
41 * notice, this list of conditions and the following disclaimer in the
42 * documentation and/or other materials provided with the distribution.
43 *
44 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
45 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
46 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
47 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
48 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
49 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
50 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
51 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
52 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
53 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
54 * SUCH DAMAGE.
55 *
56 * citrus Id: wcsstr.c,v 1.2 2000/12/21 05:07:25 itojun Exp
57 */
58
59 #include <_ansi.h>
60 #include <stddef.h>
61 #include <wchar.h>
62
63 wchar_t *
wcsstr(const wchar_t * __restrict big,const wchar_t * __restrict little)64 wcsstr (const wchar_t *__restrict big,
65 const wchar_t *__restrict little)
66 {
67 const wchar_t *p;
68 const wchar_t *q;
69 const wchar_t *r;
70
71 if (!*little)
72 {
73 /* LINTED interface specification */
74 return (wchar_t *) big;
75 }
76 if (wcslen (big) < wcslen (little))
77 return NULL;
78
79 p = big;
80 q = little;
81 while (*p)
82 {
83 q = little;
84 r = p;
85 while (*q)
86 {
87 if (*r != *q)
88 break;
89 q++;
90 r++;
91 }
92 if (!*q)
93 {
94 /* LINTED interface specification */
95 return (wchar_t *) p;
96 }
97 p++;
98 }
99 return NULL;
100 }
101
