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/*
* Copyright (c) 2009 Baptiste Coudurier <baptiste.coudurier@gmail.com>
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <unistd.h>
#include <fcntl.h>
#include "timer.h"
#include "random_seed.h"
#include "avutil.h"
static int read_random(uint32_t *dst, const char *file)
{
int fd = open(file, O_RDONLY);
int err = -1;
if (fd == -1)
return -1;
#if HAVE_FCNTL && defined(O_NONBLOCK)
if (fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK) != -1)
#endif
err = read(fd, dst, sizeof(*dst));
close(fd);
return err;
}
uint32_t av_get_random_seed(void)
{
uint32_t seed;
int err;
err = read_random(&seed, "/dev/urandom");
if (err != sizeof(seed))
err = read_random(&seed, "/dev/random");
if (err == sizeof(seed))
return seed;
#ifdef AV_READ_TIME
seed = AV_READ_TIME();
#endif
// XXX what to do ?
return seed;
}
#if LIBAVUTIL_VERSION_MAJOR < 51
attribute_deprecated uint32_t ff_random_get_seed(void);
uint32_t ff_random_get_seed(void)
{
return av_get_random_seed();
}
#endif
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