libavcodec/avpacket.c

   1 /*
   2  * AVPacket functions for libavcodec
   3  * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include "avcodec.h"
  23
  24
  25 void av_destruct_packet_nofree(AVPacket *pkt)
  26 {
  27     pkt->data = NULL; pkt->size = 0;
  28 }
  29
  30 void av_destruct_packet(AVPacket *pkt)
  31 {
  32     av_free(pkt->data);
  33     pkt->data = NULL; pkt->size = 0;
  34 }
  35
  36 void av_init_packet(AVPacket *pkt)
  37 {
  38     pkt->pts   = AV_NOPTS_VALUE;
  39     pkt->dts   = AV_NOPTS_VALUE;
  40     pkt->pos   = -1;
  41     pkt->duration = 0;
  42     pkt->convergence_duration = 0;
  43     pkt->flags = 0;
  44     pkt->stream_index = 0;
  45     pkt->destruct= av_destruct_packet_nofree;
  46 }
  47
  48 int av_new_packet(AVPacket *pkt, int size)
  49 {
  50     uint8_t *data;
  51     if((unsigned)size > (unsigned)size + FF_INPUT_BUFFER_PADDING_SIZE)
  52         return AVERROR(ENOMEM);
  53     data = av_malloc(size + FF_INPUT_BUFFER_PADDING_SIZE);
  54     if (!data)
  55         return AVERROR(ENOMEM);
  56     memset(data + size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
  57
  58     av_init_packet(pkt);
  59     pkt->data = data;
  60     pkt->size = size;
  61     pkt->destruct = av_destruct_packet;
  62     return 0;
  63 }
  64
  65 int av_dup_packet(AVPacket *pkt)
  66 {
  67     if (((pkt->destruct == av_destruct_packet_nofree) || (pkt->destruct == NULL)) && pkt->data) {
  68         uint8_t *data;
  69         /* We duplicate the packet and don't forget to add the padding again. */
  70         if((unsigned)pkt->size > (unsigned)pkt->size + FF_INPUT_BUFFER_PADDING_SIZE)
  71             return AVERROR(ENOMEM);
  72         data = av_malloc(pkt->size + FF_INPUT_BUFFER_PADDING_SIZE);
  73         if (!data) {
  74             return AVERROR(ENOMEM);
  75         }
  76         memcpy(data, pkt->data, pkt->size);
  77         memset(data + pkt->size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
  78         pkt->data = data;
  79         pkt->destruct = av_destruct_packet;
  80     }
  81     return 0;
  82 }