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
25void av_destruct_packet_nofree(AVPacket *pkt)
26{
27    pkt->data = NULL; pkt->size = 0;
28}
29
30void av_destruct_packet(AVPacket *pkt)
31{
32    av_free(pkt->data);
33    pkt->data = NULL; pkt->size = 0;
34}
35
36void 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= NULL;
46}
47
48int av_new_packet(AVPacket *pkt, int size)
49{
50    uint8_t *data= NULL;
51    if((unsigned)size < (unsigned)size + FF_INPUT_BUFFER_PADDING_SIZE)
52        data = av_malloc(size + FF_INPUT_BUFFER_PADDING_SIZE);
53    if (data){
54        memset(data + size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
55    }else
56        size=0;
57
58    av_init_packet(pkt);
59    pkt->data = data;
60    pkt->size = size;
61    pkt->destruct = av_destruct_packet;
62    if(!data)
63        return AVERROR(ENOMEM);
64    return 0;
65}
66
67void av_shrink_packet(AVPacket *pkt, int size)
68{
69    if (pkt->size <= size) return;
70    pkt->size = size;
71    memset(pkt->data + size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
72}
73
74int av_dup_packet(AVPacket *pkt)
75{
76    if (((pkt->destruct == av_destruct_packet_nofree) || (pkt->destruct == NULL)) && pkt->data) {
77        uint8_t *data;
78        /* We duplicate the packet and don't forget to add the padding again. */
79        if((unsigned)pkt->size > (unsigned)pkt->size + FF_INPUT_BUFFER_PADDING_SIZE)
80            return AVERROR(ENOMEM);
81        data = av_malloc(pkt->size + FF_INPUT_BUFFER_PADDING_SIZE);
82        if (!data) {
83            return AVERROR(ENOMEM);
84        }
85        memcpy(data, pkt->data, pkt->size);
86        memset(data + pkt->size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
87        pkt->data = data;
88        pkt->destruct = av_destruct_packet;
89    }
90    return 0;
91}
92
93void av_free_packet(AVPacket *pkt)
94{
95    if (pkt) {
96        if (pkt->destruct) pkt->destruct(pkt);
97        pkt->data = NULL; pkt->size = 0;
98    }
99}
100