1 | /* Copyright (C) 1996-2017 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | Contributed by Ulrich Drepper <drepper@gnu.org>, 1996. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <http://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <wchar.h> |
20 | |
21 | #ifdef WMEMCHR |
22 | # define __wmemchr WMEMCHR |
23 | #endif |
24 | |
25 | wchar_t * |
26 | __wmemchr (const wchar_t *s, wchar_t c, size_t n) |
27 | { |
28 | /* For performance reasons unfold the loop four times. */ |
29 | while (n >= 4) |
30 | { |
31 | if (s[0] == c) |
32 | return (wchar_t *) s; |
33 | if (s[1] == c) |
34 | return (wchar_t *) &s[1]; |
35 | if (s[2] == c) |
36 | return (wchar_t *) &s[2]; |
37 | if (s[3] == c) |
38 | return (wchar_t *) &s[3]; |
39 | s += 4; |
40 | n -= 4; |
41 | } |
42 | |
43 | if (n > 0) |
44 | { |
45 | if (*s == c) |
46 | return (wchar_t *) s; |
47 | ++s; |
48 | --n; |
49 | } |
50 | if (n > 0) |
51 | { |
52 | if (*s == c) |
53 | return (wchar_t *) s; |
54 | ++s; |
55 | --n; |
56 | } |
57 | if (n > 0) |
58 | if (*s == c) |
59 | return (wchar_t *) s; |
60 | |
61 | return NULL; |
62 | } |
63 | libc_hidden_def (__wmemchr) |
64 | weak_alias (__wmemchr, wmemchr) |
65 | libc_hidden_weak (wmemchr) |
66 | |