Libav
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 Libav.
7  *
8  * Libav 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  * Libav 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 Libav; 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_VERSION 2000
33 #define APE_TAG_FOOTER_BYTES 32
34 #define APE_TAG_FLAG_CONTAINS_HEADER (1 << 31)
35 #define APE_TAG_FLAG_CONTAINS_FOOTER (1 << 30)
36 #define APE_TAG_FLAG_IS_HEADER (1 << 29)
37 #define APE_TAG_FLAG_IS_BINARY (1 << 1)
38 
40 {
41  AVIOContext *pb = s->pb;
42  uint8_t key[1024], *value;
43  uint32_t size, flags;
44  int i, c;
45 
46  size = avio_rl32(pb); /* field size */
47  flags = avio_rl32(pb); /* field flags */
48  for (i = 0; i < sizeof(key) - 1; i++) {
49  c = avio_r8(pb);
50  if (c < 0x20 || c > 0x7E)
51  break;
52  else
53  key[i] = c;
54  }
55  key[i] = 0;
56  if (c != 0) {
57  av_log(s, AV_LOG_WARNING, "Invalid APE tag key '%s'.\n", key);
58  return -1;
59  }
60  if (size >= UINT_MAX)
61  return -1;
62  if (flags & APE_TAG_FLAG_IS_BINARY) {
63  uint8_t filename[1024];
64  enum AVCodecID id;
66  if (!st)
67  return AVERROR(ENOMEM);
68 
69  size -= avio_get_str(pb, size, filename, sizeof(filename));
70  if (size <= 0) {
71  av_log(s, AV_LOG_WARNING, "Skipping binary tag '%s'.\n", key);
72  return 0;
73  }
74 
75  av_dict_set(&st->metadata, key, filename, 0);
76 
77  if ((id = ff_guess_image2_codec(filename)) != AV_CODEC_ID_NONE) {
78  AVPacket pkt;
79  int ret;
80 
81  ret = av_get_packet(s->pb, &pkt, size);
82  if (ret < 0) {
83  av_log(s, AV_LOG_ERROR, "Error reading cover art.\n");
84  return ret;
85  }
86 
89  st->codec->codec_id = id;
90 
91  st->attached_pic = pkt;
94  } else {
96  if (!st->codec->extradata)
97  return AVERROR(ENOMEM);
98  if (avio_read(pb, st->codec->extradata, size) != size) {
99  av_freep(&st->codec->extradata);
100  return AVERROR(EIO);
101  }
102  st->codec->extradata_size = size;
104  }
105  } else {
106  value = av_malloc(size+1);
107  if (!value)
108  return AVERROR(ENOMEM);
109  c = avio_read(pb, value, size);
110  if (c < 0) {
111  av_free(value);
112  return c;
113  }
114  value[c] = 0;
115  av_dict_set(&s->metadata, key, value, AV_DICT_DONT_STRDUP_VAL);
116  }
117  return 0;
118 }
119 
121 {
122  AVIOContext *pb = s->pb;
123  int64_t file_size = avio_size(pb);
124  uint32_t val, fields, tag_bytes;
125  uint8_t buf[8];
126  int64_t tag_start;
127  int i;
128 
129  if (file_size < APE_TAG_FOOTER_BYTES)
130  return 0;
131 
132  avio_seek(pb, file_size - APE_TAG_FOOTER_BYTES, SEEK_SET);
133 
134  avio_read(pb, buf, 8); /* APETAGEX */
135  if (strncmp(buf, "APETAGEX", 8)) {
136  return 0;
137  }
138 
139  val = avio_rl32(pb); /* APE tag version */
140  if (val > APE_TAG_VERSION) {
141  av_log(s, AV_LOG_ERROR, "Unsupported tag version. (>=%d)\n", APE_TAG_VERSION);
142  return 0;
143  }
144 
145  tag_bytes = avio_rl32(pb); /* tag size */
146  if (tag_bytes - APE_TAG_FOOTER_BYTES > (1024 * 1024 * 16)) {
147  av_log(s, AV_LOG_ERROR, "Tag size is way too big\n");
148  return 0;
149  }
150 
151  if (tag_bytes > file_size - APE_TAG_FOOTER_BYTES) {
152  av_log(s, AV_LOG_ERROR, "Invalid tag size %"PRIu32".\n", tag_bytes);
153  return 0;
154  }
155  tag_start = file_size - tag_bytes - APE_TAG_FOOTER_BYTES;
156 
157  fields = avio_rl32(pb); /* number of fields */
158  if (fields > 65536) {
159  av_log(s, AV_LOG_ERROR, "Too many tag fields (%"PRIu32")\n", fields);
160  return 0;
161  }
162 
163  val = avio_rl32(pb); /* flags */
164  if (val & APE_TAG_FLAG_IS_HEADER) {
165  av_log(s, AV_LOG_ERROR, "APE Tag is a header\n");
166  return 0;
167  }
168 
169  avio_seek(pb, file_size - tag_bytes, SEEK_SET);
170 
171  for (i=0; i<fields; i++)
172  if (ape_tag_read_field(s) < 0) break;
173 
174  return tag_start;
175 }
176 
178 {
179  AVDictionaryEntry *e = NULL;
180  int64_t start, end;
181  int size, count = 0;
182 
183  if (!s->pb->seekable)
184  return 0;
185 
186  start = avio_tell(s->pb);
187 
188  // header
189  avio_write(s->pb, "APETAGEX", 8); // id
190  avio_wl32 (s->pb, APE_TAG_VERSION); // version
191  avio_wl32(s->pb, 0); // reserve space for size
192  avio_wl32(s->pb, 0); // reserve space for tag count
193 
194  // flags
197  ffio_fill(s->pb, 0, 8); // reserved
198 
199  while ((e = av_dict_get(s->metadata, "", e, AV_DICT_IGNORE_SUFFIX))) {
200  int val_len = strlen(e->value);
201 
202  avio_wl32(s->pb, val_len); // value length
203  avio_wl32(s->pb, 0); // item flags
204  avio_put_str(s->pb, e->key); // key
205  avio_write(s->pb, e->value, val_len); // value
206  count++;
207  }
208 
209  size = avio_tell(s->pb) - start;
210 
211  // footer
212  avio_write(s->pb, "APETAGEX", 8); // id
213  avio_wl32 (s->pb, APE_TAG_VERSION); // version
214  avio_wl32(s->pb, size); // size
215  avio_wl32(s->pb, count); // tag count
216 
217  // flags
219  ffio_fill(s->pb, 0, 8); // reserved
220 
221  // update values in the header
222  end = avio_tell(s->pb);
223  avio_seek(s->pb, start + 12, SEEK_SET);
224  avio_wl32(s->pb, size);
225  avio_wl32(s->pb, count);
226  avio_seek(s->pb, end, SEEK_SET);
227 
228  return 0;
229 }
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:62
Bytestream IO Context.
Definition: avio.h:68
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:241
int size
enum AVCodecID id
Definition: mxfenc.c:84
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:129
#define APE_TAG_FLAG_CONTAINS_FOOTER
Definition: apetag.c:35
int index
stream index in AVFormatContext
Definition: avformat.h:700
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:186
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:198
Format I/O context.
Definition: avformat.h:922
Public dictionary API.
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:260
uint8_t
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1158
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:2497
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:38
static int flags
Definition: log.c:44
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:117
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:219
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:165
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:452
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1013
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:105
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1130
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:186
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:564
#define AVERROR(e)
Definition: error.h:43
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:168
int64_t ff_ape_parse_tag(AVFormatContext *s)
Read and parse an APE tag.
Definition: apetag.c:120
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:973
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:443
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:718
#define FF_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:531
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:117
void ffio_fill(AVIOContext *s, int b, int count)
Definition: aviobuf.c:151
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that's been allocated with av_malloc() and chilren.
Definition: dict.h:66
#define APE_TAG_FLAG_CONTAINS_HEADER
Definition: apetag.c:34
#define APE_TAG_FLAG_IS_BINARY
Definition: apetag.c:37
AVDictionary * metadata
Definition: avformat.h:771
Opaque data information usually sparse.
Definition: avutil.h:191
#define AV_DISPOSITION_ATTACHED_PIC
The stream is stored in the file as an attached picture/"cover art" (e.g.
Definition: avformat.h:690
int avio_put_str(AVIOContext *s, const char *str)
Write a NULL-terminated string.
Definition: aviobuf.c:276
Stream structure.
Definition: avformat.h:699
NULL
Definition: eval.c:55
enum AVMediaType codec_type
Definition: avcodec.h:1052
#define APE_TAG_FOOTER_BYTES
Definition: apetag.c:33
enum AVCodecID codec_id
Definition: avcodec.h:1061
AVIOContext * pb
I/O context.
Definition: avformat.h:964
int extradata_size
Definition: avcodec.h:1159
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:68
int ff_ape_write_tag(AVFormatContext *s)
Write an APE tag into a file.
Definition: apetag.c:177
#define APE_TAG_FLAG_IS_HEADER
Definition: apetag.c:36
Main libavformat public API header.
int disposition
AV_DISPOSITION_* bit field.
Definition: avformat.h:760
char * key
Definition: dict.h:75
enum AVCodecID ff_guess_image2_codec(const char *filename)
Definition: img2.c:97
char * value
Definition: dict.h:76
static int ape_tag_read_field(AVFormatContext *s)
Definition: apetag.c:39
#define AV_DICT_IGNORE_SUFFIX
Definition: dict.h:62
int avio_get_str(AVIOContext *pb, int maxlen, char *buf, int buflen)
Read a string from pb into buf.
Definition: aviobuf.c:618
int stream_index
Definition: avcodec.h:969
#define APE_TAG_VERSION
Definition: apetag.c:32
This structure stores compressed data.
Definition: avcodec.h:944
AVPacket attached_pic
For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet will contain the attached pictu...
Definition: avformat.h:789