ffmpeg / libavutil / random_seed.c @ 49e92878
History | View | Annotate | Download (1.28 KB)
1 |
/*
|
---|---|
2 |
* Copyright (c) 2009 Baptiste Coudurier <baptiste.coudurier@gmail.com>
|
3 |
*
|
4 |
* This file is part of FFmpeg.
|
5 |
*
|
6 |
* FFmpeg is free software; you can redistribute it and/or
|
7 |
* modify it under the terms of the GNU Lesser General Public
|
8 |
* License as published by the Free Software Foundation; either
|
9 |
* version 2.1 of the License, or (at your option) any later version.
|
10 |
*
|
11 |
* FFmpeg is distributed in the hope that it will be useful,
|
12 |
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
13 |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
14 |
* Lesser General Public License for more details.
|
15 |
*
|
16 |
* You should have received a copy of the GNU Lesser General Public
|
17 |
* License along with FFmpeg; if not, write to the Free Software
|
18 |
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
19 |
*/
|
20 |
|
21 |
#include <unistd.h> |
22 |
#include <fcntl.h> |
23 |
#include "timer.h" |
24 |
#include "random_seed.h" |
25 |
|
26 |
uint32_t ff_random_get_seed(void)
|
27 |
{ |
28 |
uint32_t seed; |
29 |
int fd;
|
30 |
|
31 |
if ((fd = open("/dev/random", O_RDONLY)) == -1) |
32 |
fd = open("/dev/urandom", O_RDONLY);
|
33 |
if (fd != -1){ |
34 |
int err = read(fd, &seed, 4); |
35 |
close(fd); |
36 |
if (err == 4) |
37 |
return seed;
|
38 |
} |
39 |
#ifdef AV_READ_TIME
|
40 |
seed = AV_READ_TIME(); |
41 |
#endif
|
42 |
// XXX what to do ?
|
43 |
return seed;
|
44 |
} |