Skip to content
Snippets Groups Projects
random_seed.c 1.25 KiB
Newer Older
  • Learn to ignore specific revisions
  • /*
     * 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"
    
    uint32_t ff_random_get_seed(void)
    {
        uint32_t seed;
        int fd;
    
        if ((fd = open("/dev/random", O_RDONLY)) == -1)
            fd = open("/dev/urandom", O_RDONLY);
        if (fd != -1){
            read(fd, &seed, 4);
            close(fd);
            return seed;
        }
    #ifdef AV_READ_TIME
        seed = AV_READ_TIME();
    #endif
        // XXX what to do ?
        return seed;
    }