1 | /* Copyright (C) 1996-2022 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | |
4 | The GNU C Library is free software; you can redistribute it and/or |
5 | modify it under the terms of the GNU Lesser General Public |
6 | License as published by the Free Software Foundation; either |
7 | version 2.1 of the License, or (at your option) any later version. |
8 | |
9 | The GNU C Library is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
12 | Lesser General Public License for more details. |
13 | |
14 | You should have received a copy of the GNU Lesser General Public |
15 | License along with the GNU C Library; if not, see |
16 | <https://www.gnu.org/licenses/>. */ |
17 | |
18 | #include <wchar.h> |
19 | |
20 | #ifdef WMEMCHR |
21 | # define __wmemchr WMEMCHR |
22 | #endif |
23 | |
24 | wchar_t * |
25 | __wmemchr (const wchar_t *s, wchar_t c, size_t n) |
26 | { |
27 | /* For performance reasons unfold the loop four times. */ |
28 | while (n >= 4) |
29 | { |
30 | if (s[0] == c) |
31 | return (wchar_t *) s; |
32 | if (s[1] == c) |
33 | return (wchar_t *) &s[1]; |
34 | if (s[2] == c) |
35 | return (wchar_t *) &s[2]; |
36 | if (s[3] == c) |
37 | return (wchar_t *) &s[3]; |
38 | s += 4; |
39 | n -= 4; |
40 | } |
41 | |
42 | if (n > 0) |
43 | { |
44 | if (*s == c) |
45 | return (wchar_t *) s; |
46 | ++s; |
47 | --n; |
48 | } |
49 | if (n > 0) |
50 | { |
51 | if (*s == c) |
52 | return (wchar_t *) s; |
53 | ++s; |
54 | --n; |
55 | } |
56 | if (n > 0) |
57 | if (*s == c) |
58 | return (wchar_t *) s; |
59 | |
60 | return NULL; |
61 | } |
62 | libc_hidden_def (__wmemchr) |
63 | weak_alias (__wmemchr, wmemchr) |
64 | libc_hidden_weak (wmemchr) |
65 | |