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  }
62  if (flags & APE_TAG_FLAG_IS_BINARY) {
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 (ff_get_extradata(s, st->codecpar, s->pb, size) < 0)
100  return AVERROR(ENOMEM);
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;
113  av_dict_set(&s->metadata, key, value, AV_DICT_DONT_STRDUP_VAL);
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 = NULL;
190  uint8_t *dyn_buf = NULL;
191 
192  if ((ret = avio_open_dyn_buf(&dyn_bc)) < 0)
193  goto end;
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_close_dyn_buf(dyn_bc, &dyn_buf);
215  if (size <= 0)
216  goto end;
217  size += APE_TAG_FOOTER_BYTES;
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  if (dyn_bc && !dyn_buf)
243  avio_close_dyn_buf(dyn_bc, &dyn_buf);
244  av_freep(&dyn_buf);
245 
246  return ret;
247 }
#define NULL
Definition: coverity.c:32
const char const char void * val
Definition: avisynth_c.h:863
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:339
int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
Return the written size and a pointer to the buffer.
Definition: aviobuf.c:1459
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3968
int index
stream index in AVFormatContext
Definition: avformat.h:882
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
const char * key
static AVPacket pkt
int avio_open_dyn_buf(AVIOContext **s)
Open a write only memory stream.
Definition: aviobuf.c:1430
Format I/O context.
Definition: avformat.h:1358
Public dictionary API.
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:372
uint8_t
#define av_malloc(s)
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
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
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:108
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4499
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
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
ptrdiff_t size
Definition: opengl_enc.c:100
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:218
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:650
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1512
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:215
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1598
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:772
#define APE_TAG_HEADER_BYTES
Definition: apetag.h:31
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3964
int ff_standardize_creation_time(AVFormatContext *s)
Standardize creation_time metadata in AVFormatContext to an ISO-8601 timestamp string.
Definition: utils.c:5710
GLsizei count
Definition: opengl_enc.c:108
int64_t ff_ape_parse_tag(AVFormatContext *s)
Read and parse an APE tag.
Definition: apetag.c:118
#define APE_TAG_PREAMBLE
Definition: apetag.h:28
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1486
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:641
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
void ffio_fill(AVIOContext *s, int b, int count)
Definition: aviobuf.c:204
static int string_is_ascii(const uint8_t *str)
Definition: apetag.c:179
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that&#39;s been allocated with av_malloc() or another memory allocation functio...
Definition: dict.h:76
#define APE_TAG_FLAG_CONTAINS_HEADER
Definition: apetag.c:32
#define APE_TAG_VERSION
Definition: apetag.h:29
#define APE_TAG_FLAG_IS_BINARY
Definition: apetag.c:35
#define s(width, name)
Definition: cbs_vp9.c:257
AVDictionary * metadata
Definition: avformat.h:945
Opaque data information usually sparse.
Definition: avutil.h:205
#define APE_TAG_FOOTER_BYTES
Definition: apetag.h:30
#define AV_DISPOSITION_ATTACHED_PIC
The stream is stored in the file as an attached picture/"cover art" (e.g.
Definition: avformat.h:849
int avio_put_str(AVIOContext *s, const char *str)
Write a NULL-terminated string.
Definition: aviobuf.c:388
Stream structure.
Definition: avformat.h:881
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
void * buf
Definition: avisynth_c.h:766
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
int ff_ape_write_tag(AVFormatContext *s)
Write an APE tag into a file.
Definition: apetag.c:185
#define flags(name, subs,...)
Definition: cbs_av1.c:561
#define APE_TAG_FLAG_IS_HEADER
Definition: apetag.c:34
Main libavformat public API header.
int disposition
AV_DISPOSITION_* bit field.
Definition: avformat.h:934
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:3339
char * key
Definition: dict.h:86
enum AVCodecID ff_guess_image2_codec(const char *filename)
Definition: img2.c:103
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:793
#define av_free(p)
char * value
Definition: dict.h:87
static int ape_tag_read_field(AVFormatContext *s)
Definition: apetag.c:37
#define av_freep(p)
#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
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int avio_get_str(AVIOContext *pb, int maxlen, char *buf, int buflen)
Read a string from pb into buf.
Definition: aviobuf.c:882
int stream_index
Definition: avcodec.h:1482
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
enum AVCodecID id
This structure stores compressed data.
Definition: avcodec.h:1457
AVPacket attached_pic
For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet will contain the attached pictu...
Definition: avformat.h:963