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ffmpeg / libavutil / random_seed.c @ 49e92878

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/*
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 * Copyright (c) 2009 Baptiste Coudurier <baptiste.coudurier@gmail.com>
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#include <unistd.h>
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#include <fcntl.h>
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#include "timer.h"
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#include "random_seed.h"
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uint32_t ff_random_get_seed(void)
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{
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    uint32_t seed;
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    int fd;
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    if ((fd = open("/dev/random", O_RDONLY)) == -1)
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        fd = open("/dev/urandom", O_RDONLY);
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    if (fd != -1){
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        int err = read(fd, &seed, 4);
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        close(fd);
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        if (err == 4)
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        return seed;
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    }
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#ifdef AV_READ_TIME
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    seed = AV_READ_TIME();
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#endif
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    // XXX what to do ?
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    return seed;
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}