blob: 49b9a3dc94049941407b77a5e7af4cdccd985f4f (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
|
/* Swap the content of two memory blocks, overlap is NOT handled.
Copyright (C) 2023-2024 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <string.h>
static inline void
__memswap (void *__restrict p1, void *__restrict p2, size_t n)
{
/* Use multiple small memcpys with constant size to enable inlining on most
targets. */
enum { SWAP_GENERIC_SIZE = 32 };
unsigned char tmp[SWAP_GENERIC_SIZE];
while (n > SWAP_GENERIC_SIZE)
{
memcpy (tmp, p1, SWAP_GENERIC_SIZE);
p1 = __mempcpy (p1, p2, SWAP_GENERIC_SIZE);
p2 = __mempcpy (p2, tmp, SWAP_GENERIC_SIZE);
n -= SWAP_GENERIC_SIZE;
}
while (n > 0)
{
unsigned char t = ((unsigned char *)p1)[--n];
((unsigned char *)p1)[n] = ((unsigned char *)p2)[n];
((unsigned char *)p2)[n] = t;
}
}
|
