Imported Debian version 2.5.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / dvdsub_parser.c
1 /*
2 * DVD subtitle decoding
3 * Copyright (c) 2005 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 <string.h>
23
24 #include "libavutil/intreadwrite.h"
25 #include "libavutil/mem.h"
26 #include "avcodec.h"
27
28 /* parser definition */
29 typedef struct DVDSubParseContext {
30 uint8_t *packet;
31 int packet_len;
32 int packet_index;
33 } DVDSubParseContext;
34
35 static av_cold int dvdsub_parse_init(AVCodecParserContext *s)
36 {
37 return 0;
38 }
39
40 static int dvdsub_parse(AVCodecParserContext *s,
41 AVCodecContext *avctx,
42 const uint8_t **poutbuf, int *poutbuf_size,
43 const uint8_t *buf, int buf_size)
44 {
45 DVDSubParseContext *pc = s->priv_data;
46
47 if (pc->packet_index == 0) {
48 if (buf_size < 2 || AV_RB16(buf) && buf_size < 6) {
49 if (buf_size)
50 av_log(avctx, AV_LOG_DEBUG, "Parser input %d too small\n", buf_size);
51 return buf_size;
52 }
53 pc->packet_len = AV_RB16(buf);
54 if (pc->packet_len == 0) /* HD-DVD subpicture packet */
55 pc->packet_len = AV_RB32(buf+2);
56 av_freep(&pc->packet);
57 pc->packet = av_malloc(pc->packet_len);
58 }
59 if (pc->packet) {
60 if (pc->packet_index + buf_size <= pc->packet_len) {
61 memcpy(pc->packet + pc->packet_index, buf, buf_size);
62 pc->packet_index += buf_size;
63 if (pc->packet_index >= pc->packet_len) {
64 *poutbuf = pc->packet;
65 *poutbuf_size = pc->packet_len;
66 pc->packet_index = 0;
67 return buf_size;
68 }
69 } else {
70 /* erroneous size */
71 pc->packet_index = 0;
72 }
73 }
74 *poutbuf = NULL;
75 *poutbuf_size = 0;
76 return buf_size;
77 }
78
79 static av_cold void dvdsub_parse_close(AVCodecParserContext *s)
80 {
81 DVDSubParseContext *pc = s->priv_data;
82 av_freep(&pc->packet);
83 }
84
85 AVCodecParser ff_dvdsub_parser = {
86 .codec_ids = { AV_CODEC_ID_DVD_SUBTITLE },
87 .priv_data_size = sizeof(DVDSubParseContext),
88 .parser_init = dvdsub_parse_init,
89 .parser_parse = dvdsub_parse,
90 .parser_close = dvdsub_parse_close,
91 };