1 /*
2 * ID3v2 header writer
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #include <stdint.h>
22 #include <string.h>
23
24 #include "libavutil/avstring.h"
25 #include "libavutil/dict.h"
26 #include "libavutil/intreadwrite.h"
27 #include "avformat.h"
28 #include "avio.h"
29 #include "avio_internal.h"
30 #include "id3v2.h"
31
id3v2_put_size(AVIOContext * pb,int size)32 static void id3v2_put_size(AVIOContext *pb, int size)
33 {
34 avio_w8(pb, size >> 21 & 0x7f);
35 avio_w8(pb, size >> 14 & 0x7f);
36 avio_w8(pb, size >> 7 & 0x7f);
37 avio_w8(pb, size & 0x7f);
38 }
39
string_is_ascii(const uint8_t * str)40 static int string_is_ascii(const uint8_t *str)
41 {
42 while (*str && *str < 128) str++;
43 return !*str;
44 }
45
id3v2_encode_string(AVIOContext * pb,const uint8_t * str,enum ID3v2Encoding enc)46 static void id3v2_encode_string(AVIOContext *pb, const uint8_t *str,
47 enum ID3v2Encoding enc)
48 {
49 int (*put)(AVIOContext*, const char*);
50
51 if (enc == ID3v2_ENCODING_UTF16BOM) {
52 avio_wl16(pb, 0xFEFF); /* BOM */
53 put = avio_put_str16le;
54 } else
55 put = avio_put_str;
56
57 put(pb, str);
58 }
59
60 /**
61 * Write a text frame with one (normal frames) or two (TXXX frames) strings
62 * according to encoding (only UTF-8 or UTF-16+BOM supported).
63 * @return number of bytes written or a negative error code.
64 */
id3v2_put_ttag(ID3v2EncContext * id3,AVIOContext * avioc,const char * str1,const char * str2,uint32_t tag,enum ID3v2Encoding enc)65 static int id3v2_put_ttag(ID3v2EncContext *id3, AVIOContext *avioc, const char *str1, const char *str2,
66 uint32_t tag, enum ID3v2Encoding enc)
67 {
68 int len;
69 uint8_t *pb;
70 AVIOContext *dyn_buf;
71 if (avio_open_dyn_buf(&dyn_buf) < 0)
72 return AVERROR(ENOMEM);
73
74 /* check if the strings are ASCII-only and use UTF16 only if
75 * they're not */
76 if (enc == ID3v2_ENCODING_UTF16BOM && string_is_ascii(str1) &&
77 (!str2 || string_is_ascii(str2)))
78 enc = ID3v2_ENCODING_ISO8859;
79
80 avio_w8(dyn_buf, enc);
81 id3v2_encode_string(dyn_buf, str1, enc);
82 if (str2)
83 id3v2_encode_string(dyn_buf, str2, enc);
84 len = avio_close_dyn_buf(dyn_buf, &pb);
85
86 avio_wb32(avioc, tag);
87 /* ID3v2.3 frame size is not synchsafe */
88 if (id3->version == 3)
89 avio_wb32(avioc, len);
90 else
91 id3v2_put_size(avioc, len);
92 avio_wb16(avioc, 0);
93 avio_write(avioc, pb, len);
94
95 av_freep(&pb);
96 return len + ID3v2_HEADER_SIZE;
97 }
98
id3v2_check_write_tag(ID3v2EncContext * id3,AVIOContext * pb,AVDictionaryEntry * t,const char table[][4],enum ID3v2Encoding enc)99 static int id3v2_check_write_tag(ID3v2EncContext *id3, AVIOContext *pb, AVDictionaryEntry *t,
100 const char table[][4], enum ID3v2Encoding enc)
101 {
102 uint32_t tag;
103 int i;
104
105 if (t->key[0] != 'T' || strlen(t->key) != 4)
106 return -1;
107 tag = AV_RB32(t->key);
108 for (i = 0; *table[i]; i++)
109 if (tag == AV_RB32(table[i]))
110 return id3v2_put_ttag(id3, pb, t->value, NULL, tag, enc);
111 return -1;
112 }
113
id3v2_3_metadata_split_date(AVDictionary ** pm)114 static void id3v2_3_metadata_split_date(AVDictionary **pm)
115 {
116 AVDictionaryEntry *mtag = NULL;
117 AVDictionary *dst = NULL;
118 const char *key, *value;
119 char year[5] = {0}, day_month[5] = {0};
120 int i;
121
122 while ((mtag = av_dict_get(*pm, "", mtag, AV_DICT_IGNORE_SUFFIX))) {
123 key = mtag->key;
124 if (!av_strcasecmp(key, "date")) {
125 /* split date tag using "YYYY-MM-DD" format into year and month/day segments */
126 value = mtag->value;
127 i = 0;
128 while (value[i] >= '0' && value[i] <= '9') i++;
129 if (value[i] == '\0' || value[i] == '-') {
130 av_strlcpy(year, value, sizeof(year));
131 av_dict_set(&dst, "TYER", year, 0);
132
133 if (value[i] == '-' &&
134 value[i+1] >= '0' && value[i+1] <= '1' &&
135 value[i+2] >= '0' && value[i+2] <= '9' &&
136 value[i+3] == '-' &&
137 value[i+4] >= '0' && value[i+4] <= '3' &&
138 value[i+5] >= '0' && value[i+5] <= '9' &&
139 (value[i+6] == '\0' || value[i+6] == ' ')) {
140 snprintf(day_month, sizeof(day_month), "%.2s%.2s", value + i + 4, value + i + 1);
141 av_dict_set(&dst, "TDAT", day_month, 0);
142 }
143 } else
144 av_dict_set(&dst, key, value, 0);
145 } else
146 av_dict_set(&dst, key, mtag->value, 0);
147 }
148 av_dict_free(pm);
149 *pm = dst;
150 }
151
ff_id3v2_start(ID3v2EncContext * id3,AVIOContext * pb,int id3v2_version,const char * magic)152 void ff_id3v2_start(ID3v2EncContext *id3, AVIOContext *pb, int id3v2_version,
153 const char *magic)
154 {
155 id3->version = id3v2_version;
156
157 avio_wb32(pb, MKBETAG(magic[0], magic[1], magic[2], id3v2_version));
158 avio_w8(pb, 0);
159 avio_w8(pb, 0); /* flags */
160
161 /* reserve space for size */
162 id3->size_pos = avio_tell(pb);
163 avio_wb32(pb, 0);
164 }
165
write_metadata(AVIOContext * pb,AVDictionary ** metadata,ID3v2EncContext * id3,int enc)166 static int write_metadata(AVIOContext *pb, AVDictionary **metadata,
167 ID3v2EncContext *id3, int enc)
168 {
169 AVDictionaryEntry *t = NULL;
170 int ret;
171
172 ff_metadata_conv(metadata, ff_id3v2_34_metadata_conv, NULL);
173 if (id3->version == 3)
174 id3v2_3_metadata_split_date(metadata);
175 else if (id3->version == 4)
176 ff_metadata_conv(metadata, ff_id3v2_4_metadata_conv, NULL);
177
178 while ((t = av_dict_get(*metadata, "", t, AV_DICT_IGNORE_SUFFIX))) {
179 if ((ret = id3v2_check_write_tag(id3, pb, t, ff_id3v2_tags, enc)) > 0) {
180 id3->len += ret;
181 continue;
182 }
183 if ((ret = id3v2_check_write_tag(id3, pb, t, id3->version == 3 ?
184 ff_id3v2_3_tags : ff_id3v2_4_tags, enc)) > 0) {
185 id3->len += ret;
186 continue;
187 }
188
189 /* unknown tag, write as TXXX frame */
190 if ((ret = id3v2_put_ttag(id3, pb, t->key, t->value, MKBETAG('T', 'X', 'X', 'X'), enc)) < 0)
191 return ret;
192 id3->len += ret;
193 }
194
195 return 0;
196 }
197
write_chapter(AVFormatContext * s,ID3v2EncContext * id3,int id,int enc)198 static int write_chapter(AVFormatContext *s, ID3v2EncContext *id3, int id, int enc)
199 {
200 const AVRational time_base = {1, 1000};
201 AVChapter *ch = s->chapters[id];
202 uint8_t *dyn_buf = NULL;
203 AVIOContext *dyn_bc = NULL;
204 char name[123];
205 int len, start, end, ret;
206
207 if ((ret = avio_open_dyn_buf(&dyn_bc)) < 0)
208 goto fail;
209
210 start = av_rescale_q(ch->start, ch->time_base, time_base);
211 end = av_rescale_q(ch->end, ch->time_base, time_base);
212
213 snprintf(name, 122, "ch%d", id);
214 id3->len += avio_put_str(dyn_bc, name);
215 avio_wb32(dyn_bc, start);
216 avio_wb32(dyn_bc, end);
217 avio_wb32(dyn_bc, 0xFFFFFFFFu);
218 avio_wb32(dyn_bc, 0xFFFFFFFFu);
219
220 if ((ret = write_metadata(dyn_bc, &ch->metadata, id3, enc)) < 0)
221 goto fail;
222
223 len = avio_close_dyn_buf(dyn_bc, &dyn_buf);
224 id3->len += 16 + ID3v2_HEADER_SIZE;
225
226 avio_wb32(s->pb, MKBETAG('C', 'H', 'A', 'P'));
227 avio_wb32(s->pb, len);
228 avio_wb16(s->pb, 0);
229 avio_write(s->pb, dyn_buf, len);
230
231 fail:
232 if (dyn_bc && !dyn_buf)
233 avio_close_dyn_buf(dyn_bc, &dyn_buf);
234 av_freep(&dyn_buf);
235
236 return ret;
237 }
238
ff_id3v2_write_metadata(AVFormatContext * s,ID3v2EncContext * id3)239 int ff_id3v2_write_metadata(AVFormatContext *s, ID3v2EncContext *id3)
240 {
241 int enc = id3->version == 3 ? ID3v2_ENCODING_UTF16BOM :
242 ID3v2_ENCODING_UTF8;
243 int i, ret;
244
245 if ((ret = write_metadata(s->pb, &s->metadata, id3, enc)) < 0)
246 return ret;
247
248 for (i = 0; i < s->nb_chapters; i++) {
249 if ((ret = write_chapter(s, id3, i, enc)) < 0)
250 return ret;
251 }
252
253 return 0;
254 }
255
ff_id3v2_write_apic(AVFormatContext * s,ID3v2EncContext * id3,AVPacket * pkt)256 int ff_id3v2_write_apic(AVFormatContext *s, ID3v2EncContext *id3, AVPacket *pkt)
257 {
258 AVStream *st = s->streams[pkt->stream_index];
259 AVDictionaryEntry *e;
260
261 AVIOContext *dyn_buf;
262 uint8_t *buf;
263 const CodecMime *mime = ff_id3v2_mime_tags;
264 const char *mimetype = NULL, *desc = "";
265 int enc = id3->version == 3 ? ID3v2_ENCODING_UTF16BOM :
266 ID3v2_ENCODING_UTF8;
267 int i, len, type = 0;
268
269 /* get the mimetype*/
270 while (mime->id != AV_CODEC_ID_NONE) {
271 if (mime->id == st->codec->codec_id) {
272 mimetype = mime->str;
273 break;
274 }
275 mime++;
276 }
277 if (!mimetype) {
278 av_log(s, AV_LOG_ERROR, "No mimetype is known for stream %d, cannot "
279 "write an attached picture.\n", st->index);
280 return AVERROR(EINVAL);
281 }
282
283 /* get the picture type */
284 e = av_dict_get(st->metadata, "comment", NULL, 0);
285 for (i = 0; e && i < FF_ARRAY_ELEMS(ff_id3v2_picture_types); i++) {
286 if (!av_strcasecmp(e->value, ff_id3v2_picture_types[i])) {
287 type = i;
288 break;
289 }
290 }
291
292 /* get the description */
293 if ((e = av_dict_get(st->metadata, "title", NULL, 0)))
294 desc = e->value;
295
296 /* use UTF16 only for non-ASCII strings */
297 if (enc == ID3v2_ENCODING_UTF16BOM && string_is_ascii(desc))
298 enc = ID3v2_ENCODING_ISO8859;
299
300 /* start writing */
301 if (avio_open_dyn_buf(&dyn_buf) < 0)
302 return AVERROR(ENOMEM);
303
304 avio_w8(dyn_buf, enc);
305 avio_put_str(dyn_buf, mimetype);
306 avio_w8(dyn_buf, type);
307 id3v2_encode_string(dyn_buf, desc, enc);
308 avio_write(dyn_buf, pkt->data, pkt->size);
309 len = avio_close_dyn_buf(dyn_buf, &buf);
310
311 avio_wb32(s->pb, MKBETAG('A', 'P', 'I', 'C'));
312 if (id3->version == 3)
313 avio_wb32(s->pb, len);
314 else
315 id3v2_put_size(s->pb, len);
316 avio_wb16(s->pb, 0);
317 avio_write(s->pb, buf, len);
318 av_freep(&buf);
319
320 id3->len += len + ID3v2_HEADER_SIZE;
321
322 return 0;
323 }
324
ff_id3v2_finish(ID3v2EncContext * id3,AVIOContext * pb,int padding_bytes)325 void ff_id3v2_finish(ID3v2EncContext *id3, AVIOContext *pb,
326 int padding_bytes)
327 {
328 int64_t cur_pos;
329
330 if (padding_bytes < 0)
331 padding_bytes = 10;
332
333 /* The ID3v2.3 specification states that 28 bits are used to represent the
334 * size of the whole tag. Therefore the current size of the tag needs to be
335 * subtracted from the upper limit of 2^28-1 to clip the value correctly. */
336 /* The minimum of 10 is an arbitrary amount of padding at the end of the tag
337 * to fix cover art display with some software such as iTunes, Traktor,
338 * Serato, Torq. */
339 padding_bytes = av_clip(padding_bytes, 10, 268435455 - id3->len);
340 ffio_fill(pb, 0, padding_bytes);
341 id3->len += padding_bytes;
342
343 cur_pos = avio_tell(pb);
344 avio_seek(pb, id3->size_pos, SEEK_SET);
345 id3v2_put_size(pb, id3->len);
346 avio_seek(pb, cur_pos, SEEK_SET);
347 }
348
ff_id3v2_write_simple(struct AVFormatContext * s,int id3v2_version,const char * magic)349 int ff_id3v2_write_simple(struct AVFormatContext *s, int id3v2_version,
350 const char *magic)
351 {
352 ID3v2EncContext id3 = { 0 };
353 int ret;
354
355 ff_id3v2_start(&id3, s->pb, id3v2_version, magic);
356 if ((ret = ff_id3v2_write_metadata(s, &id3)) < 0)
357 return ret;
358 ff_id3v2_finish(&id3, s->pb, s->metadata_header_padding);
359
360 return 0;
361 }
362