/*

  * DVD subtitle decoding

  * Copyright (c) 2005 Fabrice Bellard

  *
  * 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 <string.h>
 

 #include "libavutil/intreadwrite.h"

 #include "libavutil/mem.h"

 #include "avcodec.h"
 
 /* parser definition */
 typedef struct DVDSubParseContext {
     uint8_t *packet;
     int packet_len;
     int packet_index;
 } DVDSubParseContext;
 

 static av_cold int dvdsub_parse_init(AVCodecParserContext *s)

 {
     return 0;
 }
 
 static int dvdsub_parse(AVCodecParserContext *s,
                         AVCodecContext *avctx,

                         const uint8_t **poutbuf, int *poutbuf_size,

                         const uint8_t *buf, int buf_size)
 {
     DVDSubParseContext *pc = s->priv_data;
 
     if (pc->packet_index == 0) {
         if (buf_size < 2)
             return 0;
         pc->packet_len = AV_RB16(buf);

         if (pc->packet_len == 0) /* HD-DVD subpicture packet */
             pc->packet_len = AV_RB32(buf+2);

         av_freep(&pc->packet);
         pc->packet = av_malloc(pc->packet_len);
     }
     if (pc->packet) {
         if (pc->packet_index + buf_size <= pc->packet_len) {
             memcpy(pc->packet + pc->packet_index, buf, buf_size);
             pc->packet_index += buf_size;
             if (pc->packet_index >= pc->packet_len) {
                 *poutbuf = pc->packet;
                 *poutbuf_size = pc->packet_len;
                 pc->packet_index = 0;
                 return buf_size;
             }
         } else {
             /* erroneous size */
             pc->packet_index = 0;
         }
     }
     *poutbuf = NULL;
     *poutbuf_size = 0;
     return buf_size;
 }
 

 static av_cold void dvdsub_parse_close(AVCodecParserContext *s)

 {
     DVDSubParseContext *pc = s->priv_data;
     av_freep(&pc->packet);
 }
 

 AVCodecParser ff_dvdsub_parser = {

     .codec_ids      = { AV_CODEC_ID_DVD_SUBTITLE },

     .priv_data_size = sizeof(DVDSubParseContext),
     .parser_init    = dvdsub_parse_init,
     .parser_parse   = dvdsub_parse,
     .parser_close   = dvdsub_parse_close,

 };