FFmpeg
apetag.c
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1 /*
2  * APE tag handling
3  * Copyright (c) 2007 Benjamin Zores <ben@geexbox.org>
4  * based upon libdemac from Dave Chapman.
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include <inttypes.h>
24 
25 #include "libavutil/intreadwrite.h"
26 #include "libavutil/dict.h"
27 #include "avformat.h"
28 #include "avio_internal.h"
29 #include "apetag.h"
30 #include "internal.h"
31 
32 #define APE_TAG_FLAG_CONTAINS_HEADER (1U << 31)
33 #define APE_TAG_FLAG_LACKS_FOOTER (1 << 30)
34 #define APE_TAG_FLAG_IS_HEADER (1 << 29)
35 #define APE_TAG_FLAG_IS_BINARY (1 << 1)
36 
38 {
39  AVIOContext *pb = s->pb;
40  uint8_t key[1024], *value;
41  int64_t size, flags;
42  int i, c;
43 
44  size = avio_rl32(pb); /* field size */
45  flags = avio_rl32(pb); /* field flags */
46  for (i = 0; i < sizeof(key) - 1; i++) {
47  c = avio_r8(pb);
48  if (c < 0x20 || c > 0x7E)
49  break;
50  else
51  key[i] = c;
52  }
53  key[i] = 0;
54  if (c != 0) {
55  av_log(s, AV_LOG_WARNING, "Invalid APE tag key '%s'.\n", key);
56  return -1;
57  }
58  if (size > INT32_MAX - AV_INPUT_BUFFER_PADDING_SIZE) {
59  av_log(s, AV_LOG_ERROR, "APE tag size too large.\n");
60  return AVERROR_INVALIDDATA;
61  }
63  uint8_t filename[1024];
64  enum AVCodecID id;
65  int ret;
67  if (!st)
68  return AVERROR(ENOMEM);
69 
70  ret = avio_get_str(pb, size, filename, sizeof(filename));
71  if (ret < 0)
72  return ret;
73  if (size <= ret) {
74  av_log(s, AV_LOG_WARNING, "Skipping binary tag '%s'.\n", key);
75  return 0;
76  }
77  size -= ret;
78 
79  av_dict_set(&st->metadata, key, filename, 0);
80 
81  if ((id = ff_guess_image2_codec(filename)) != AV_CODEC_ID_NONE) {
82  AVPacket pkt;
83  int ret;
84 
85  ret = av_get_packet(s->pb, &pkt, size);
86  if (ret < 0) {
87  av_log(s, AV_LOG_ERROR, "Error reading cover art.\n");
88  return ret;
89  }
90 
93  st->codecpar->codec_id = id;
94 
95  st->attached_pic = pkt;
98  } else {
99  if ((ret = ff_get_extradata(s, st->codecpar, s->pb, size)) < 0)
100  return ret;
102  }
103  } else {
104  value = av_malloc(size+1);
105  if (!value)
106  return AVERROR(ENOMEM);
107  c = avio_read(pb, value, size);
108  if (c < 0) {
109  av_free(value);
110  return c;
111  }
112  value[c] = 0;
114  }
115  return 0;
116 }
117 
119 {
120  AVIOContext *pb = s->pb;
121  int64_t file_size = avio_size(pb);
122  uint32_t val, fields, tag_bytes;
123  uint8_t buf[8];
124  int64_t tag_start;
125  int i;
126 
127  if (file_size < APE_TAG_FOOTER_BYTES)
128  return 0;
129 
130  avio_seek(pb, file_size - APE_TAG_FOOTER_BYTES, SEEK_SET);
131 
132  avio_read(pb, buf, 8); /* APETAGEX */
133  if (strncmp(buf, APE_TAG_PREAMBLE, 8)) {
134  return 0;
135  }
136 
137  val = avio_rl32(pb); /* APE tag version */
138  if (val > APE_TAG_VERSION) {
139  av_log(s, AV_LOG_ERROR, "Unsupported tag version. (>=%d)\n", APE_TAG_VERSION);
140  return 0;
141  }
142 
143  tag_bytes = avio_rl32(pb); /* tag size */
144  if (tag_bytes - APE_TAG_FOOTER_BYTES > (1024 * 1024 * 16)) {
145  av_log(s, AV_LOG_ERROR, "Tag size is way too big\n");
146  return 0;
147  }
148 
149  if (tag_bytes > file_size - APE_TAG_FOOTER_BYTES) {
150  av_log(s, AV_LOG_ERROR, "Invalid tag size %"PRIu32".\n", tag_bytes);
151  return 0;
152  }
153 
154  fields = avio_rl32(pb); /* number of fields */
155  if (fields > 65536) {
156  av_log(s, AV_LOG_ERROR, "Too many tag fields (%"PRIu32")\n", fields);
157  return 0;
158  }
159 
160  val = avio_rl32(pb); /* flags */
161  if (val & APE_TAG_FLAG_IS_HEADER) {
162  av_log(s, AV_LOG_ERROR, "APE Tag is a header\n");
163  return 0;
164  }
165 
166  avio_seek(pb, file_size - tag_bytes, SEEK_SET);
167 
169  tag_bytes += APE_TAG_HEADER_BYTES;
170 
171  tag_start = file_size - tag_bytes;
172 
173  for (i=0; i<fields; i++)
174  if (ape_tag_read_field(s) < 0) break;
175 
176  return tag_start;
177 }
178 
179 static int string_is_ascii(const uint8_t *str)
180 {
181  while (*str && *str >= 0x20 && *str <= 0x7e ) str++;
182  return !*str;
183 }
184 
186 {
187  AVDictionaryEntry *e = NULL;
188  int size, ret, count = 0;
189  AVIOContext *dyn_bc;
190  uint8_t *dyn_buf;
191 
192  if ((ret = avio_open_dyn_buf(&dyn_bc)) < 0)
193  return ret;
194 
196  while ((e = av_dict_get(s->metadata, "", e, AV_DICT_IGNORE_SUFFIX))) {
197  int val_len;
198 
199  if (!string_is_ascii(e->key)) {
200  av_log(s, AV_LOG_WARNING, "Non ASCII keys are not allowed\n");
201  continue;
202  }
203 
204  val_len = strlen(e->value);
205  avio_wl32(dyn_bc, val_len); // value length
206  avio_wl32(dyn_bc, 0); // item flags
207  avio_put_str(dyn_bc, e->key); // key
208  avio_write(dyn_bc, e->value, val_len); // value
209  count++;
210  }
211  if (!count)
212  goto end;
213 
214  size = avio_get_dyn_buf(dyn_bc, &dyn_buf);
215  if (size <= 0)
216  goto end;
218 
219  // header
220  avio_write(s->pb, "APETAGEX", 8); // id
221  avio_wl32(s->pb, APE_TAG_VERSION); // version
222  avio_wl32(s->pb, size);
223  avio_wl32(s->pb, count);
224 
225  // flags
227  ffio_fill(s->pb, 0, 8); // reserved
228 
229  avio_write(s->pb, dyn_buf, size - APE_TAG_FOOTER_BYTES);
230 
231  // footer
232  avio_write(s->pb, "APETAGEX", 8); // id
233  avio_wl32(s->pb, APE_TAG_VERSION); // version
234  avio_wl32(s->pb, size); // size
235  avio_wl32(s->pb, count); // tag count
236 
237  // flags
239  ffio_fill(s->pb, 0, 8); // reserved
240 
241 end:
242  ffio_free_dyn_buf(&dyn_bc);
243 
244  return ret;
245 }
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4509
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
ff_get_extradata
int ff_get_extradata(AVFormatContext *s, AVCodecParameters *par, AVIOContext *pb, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0 and f...
Definition: utils.c:3332
AV_DISPOSITION_ATTACHED_PIC
#define AV_DISPOSITION_ATTACHED_PIC
The stream is stored in the file as an attached picture/"cover art" (e.g.
Definition: avformat.h:841
apetag.h
ff_guess_image2_codec
enum AVCodecID ff_guess_image2_codec(const char *filename)
Definition: img2.c:106
AV_DICT_IGNORE_SUFFIX
#define AV_DICT_IGNORE_SUFFIX
Return first entry in a dictionary whose first part corresponds to the search key,...
Definition: dict.h:70
APE_TAG_FLAG_IS_BINARY
#define APE_TAG_FLAG_IS_BINARY
Definition: apetag.c:35
avio_size
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:342
avio_get_dyn_buf
int avio_get_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
Return the written size and a pointer to the buffer.
Definition: aviobuf.c:1391
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:410
APE_TAG_PREAMBLE
#define APE_TAG_PREAMBLE
Definition: apetag.h:28
ff_ape_parse_tag
int64_t ff_ape_parse_tag(AVFormatContext *s)
Read and parse an APE tag.
Definition: apetag.c:118
APE_TAG_VERSION
#define APE_TAG_VERSION
Definition: apetag.h:29
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:31
string_is_ascii
static int string_is_ascii(const uint8_t *str)
Definition: apetag.c:179
ape_tag_read_field
static int ape_tag_read_field(AVFormatContext *s)
Definition: apetag.c:37
val
static double val(void *priv, double ch)
Definition: aeval.c:76
APE_TAG_FLAG_CONTAINS_HEADER
#define APE_TAG_FLAG_CONTAINS_HEADER
Definition: apetag.c:32
AVStream::attached_pic
AVPacket attached_pic
For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet will contain the attached pictu...
Definition: avformat.h:955
AV_DICT_DONT_STRDUP_VAL
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that's been allocated with av_malloc() or another memory allocation functio...
Definition: dict.h:74
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
av_dict_get
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
avio_open_dyn_buf
int avio_open_dyn_buf(AVIOContext **s)
Open a write only memory stream.
Definition: aviobuf.c:1379
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVDictionaryEntry::key
char * key
Definition: dict.h:82
key
const char * key
Definition: hwcontext_opencl.c:168
ff_ape_write_tag
int ff_ape_write_tag(AVFormatContext *s)
Write an APE tag into a file.
Definition: apetag.c:185
fields
the definition of that something depends on the semantic of the filter The callback must examine the status of the filter s links and proceed accordingly The status of output links is stored in the status_in and status_out fields and tested by the then the processing requires a frame on this link and the filter is expected to make efforts in that direction The status of input links is stored by the fifo and status_out fields
Definition: filter_design.txt:155
APE_TAG_FLAG_IS_HEADER
#define APE_TAG_FLAG_IS_HEADER
Definition: apetag.c:34
AVFormatContext
Format I/O context.
Definition: avformat.h:1232
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
NULL
#define NULL
Definition: coverity.c:32
AVStream::metadata
AVDictionary * metadata
Definition: avformat.h:937
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:46
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:750
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
id
enum AVCodecID id
Definition: extract_extradata_bsf.c:325
avio_get_str
int avio_get_str(AVIOContext *pb, int maxlen, char *buf, int buflen)
Read a string from pb into buf.
Definition: aviobuf.c:860
size
int size
Definition: twinvq_data.h:10344
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:225
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:624
avio_wl32
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:375
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:375
ff_standardize_creation_time
int ff_standardize_creation_time(AVFormatContext *s)
Standardize creation_time metadata in AVFormatContext to an ISO-8601 timestamp string.
Definition: utils.c:5721
i
int i
Definition: input.c:407
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:47
avio_internal.h
value
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default value
Definition: writing_filters.txt:86
AVMEDIA_TYPE_ATTACHMENT
@ AVMEDIA_TYPE_ATTACHMENT
Opaque data information usually sparse.
Definition: avutil.h:205
uint8_t
uint8_t
Definition: audio_convert.c:194
av_get_packet
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:310
AVStream::disposition
int disposition
AV_DISPOSITION_* bit field.
Definition: avformat.h:926
ffio_free_dyn_buf
void ffio_free_dyn_buf(AVIOContext **s)
Free a dynamic buffer.
Definition: aviobuf.c:1454
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:873
APE_TAG_HEADER_BYTES
#define APE_TAG_HEADER_BYTES
Definition: apetag.h:31
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
avformat.h
dict.h
AV_INPUT_BUFFER_PADDING_SIZE
#define AV_INPUT_BUFFER_PADDING_SIZE
Definition: avcodec.h:215
AVStream::index
int index
stream index in AVFormatContext
Definition: avformat.h:874
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
APE_TAG_FOOTER_BYTES
#define APE_TAG_FOOTER_BYTES
Definition: apetag.h:30
AVPacket::stream_index
int stream_index
Definition: packet.h:371
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
av_free
#define av_free(p)
Definition: tableprint_vlc.h:34
AVDictionaryEntry
Definition: dict.h:81
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVPacket
This structure stores compressed data.
Definition: packet.h:346
av_dict_set
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
convert_header.str
string str
Definition: convert_header.py:20
ffio_fill
void ffio_fill(AVIOContext *s, int b, int count)
Definition: aviobuf.c:211
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AVDictionaryEntry::value
char * value
Definition: dict.h:83
avio_put_str
int avio_put_str(AVIOContext *s, const char *str)
Write a NULL-terminated string.
Definition: aviobuf.c:391