FFmpeg  4.0
vorbiscomment.c
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1 /*
2  * VorbisComment writer
3  * Copyright (c) 2009 James Darnley
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 "avformat.h"
23 #include "metadata.h"
24 #include "vorbiscomment.h"
25 #include "libavcodec/bytestream.h"
26 #include "libavutil/dict.h"
27 
28 /**
29  * VorbisComment metadata conversion mapping.
30  * from Ogg Vorbis I format specification: comment field and header specification
31  * http://xiph.org/vorbis/doc/v-comment.html
32  */
34  { "ALBUMARTIST", "album_artist"},
35  { "TRACKNUMBER", "track" },
36  { "DISCNUMBER", "disc" },
37  { "DESCRIPTION", "comment" },
38  { 0 }
39 };
40 
41 int64_t ff_vorbiscomment_length(AVDictionary *m, const char *vendor_string)
42 {
43  int64_t len = 8;
44  len += strlen(vendor_string);
45  if (m) {
47  while ((tag = av_dict_get(m, "", tag, AV_DICT_IGNORE_SUFFIX))) {
48  len += 4 +strlen(tag->key) + 1 + strlen(tag->value);
49  }
50  }
51  return len;
52 }
53 
55  const char *vendor_string)
56 {
57  bytestream_put_le32(p, strlen(vendor_string));
58  bytestream_put_buffer(p, vendor_string, strlen(vendor_string));
59  if (*m) {
60  int count = av_dict_count(*m);
62  bytestream_put_le32(p, count);
63  while ((tag = av_dict_get(*m, "", tag, AV_DICT_IGNORE_SUFFIX))) {
64  int64_t len1 = strlen(tag->key);
65  int64_t len2 = strlen(tag->value);
66  if (len1+1+len2 > UINT32_MAX)
67  return AVERROR(EINVAL);
68  bytestream_put_le32(p, len1+1+len2);
69  bytestream_put_buffer(p, tag->key, len1);
70  bytestream_put_byte(p, '=');
71  bytestream_put_buffer(p, tag->value, len2);
72  }
73  } else
74  bytestream_put_le32(p, 0);
75  return 0;
76 }
#define NULL
Definition: coverity.c:32
int av_dict_count(const AVDictionary *m)
Get number of entries in dictionary.
Definition: dict.c:35
int ff_vorbiscomment_write(uint8_t **p, AVDictionary **m, const char *vendor_string)
Write a VorbisComment into a buffer.
Definition: vorbiscomment.c:54
internal metadata API header see avformat.h or the public API!
Public dictionary API.
uint8_t
AVDictionaryEntry * av_dict_get(const AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
Definition: dict.c:40
uint32_t tag
Definition: movenc.c:1455
const AVMetadataConv ff_vorbiscomment_metadata_conv[]
VorbisComment metadata conversion mapping.
Definition: vorbiscomment.c:33
#define AVERROR(e)
Definition: error.h:43
int64_t ff_vorbiscomment_length(AVDictionary *m, const char *vendor_string)
Calculate the length in bytes of a VorbisComment.
Definition: vorbiscomment.c:41
Main libavformat public API header.
char * key
Definition: dict.h:86
static av_always_inline void bytestream_put_buffer(uint8_t **b, const uint8_t *src, unsigned int size)
Definition: bytestream.h:368
char * value
Definition: dict.h:87
int len
void INT64 INT64 count
Definition: avisynth_c.h:690
#define AV_DICT_IGNORE_SUFFIX
Return first entry in a dictionary whose first part corresponds to the search key, ignoring the suffix of the found key string.
Definition: dict.h:70