PeerStreamer

/*

 * Copyright (C) 2007  FFmpeg Project

 *

 * 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 "libavutil/intreadwrite.h"

#include "xiph.h"

int ff_split_xiph_headers(uint8_t *extradata, int extradata_size,

                          int first_header_size, uint8_t *header_start[3],

                          int header_len[3])

{

    int i;

    if (extradata_size >= 6 && AV_RB16(extradata) == first_header_size) {

        int overall_len = 6;

        for (i=0; i<3; i++) {

            header_len[i] = AV_RB16(extradata);

            extradata += 2;

            header_start[i] = extradata;

            extradata += header_len[i];

            if (overall_len > extradata_size - header_len[i])

                return -1;

            overall_len += header_len[i];

        }

    } else if (extradata_size >= 3 && extradata_size < INT_MAX - 0x1ff && extradata[0] == 2) {

        int overall_len = 3;

        extradata++;

        for (i=0; i<2; i++, extradata++) {

            header_len[i] = 0;

            for (; overall_len < extradata_size && *extradata==0xff; extradata++) {

                header_len[i] += 0xff;

                overall_len   += 0xff + 1;

            }

            header_len[i] += *extradata;

            overall_len   += *extradata;

            if (overall_len > extradata_size)

                return -1;

        }

        header_len[2] = extradata_size - overall_len;

        header_start[0] = extradata;

        header_start[1] = header_start[0] + header_len[0];

        header_start[2] = header_start[1] + header_len[1];

    } else {

        return -1;

    }

    return 0;

}