Convert receivers to lopsub.
[paraslash.git] / mp3_afh.c
1 /*
2 * Copyright (C) 2003 Andre Noll <maan@tuebingen.mpg.de>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file mp3_afh.c para_server's mp3 audio format handler */
8
9 /*
10 * This file is based in part on mp3tech.c and mp3tech.h, Copyright (C)
11 * 2000-2001 Cedric Tefft <cedric@earthling.net>, which in turn is based
12 * in part on
13 *
14 * * MP3Info 0.5 by Ricardo Cerqueira <rmc@rccn.net>
15 * * MP3Stat 0.9 by Ed Sweetman <safemode@voicenet.com> and
16 * Johannes Overmann <overmann@iname.com>
17 */
18
19 #include <regex.h>
20
21 #include "para.h"
22 #include "error.h"
23 #include "afh.h"
24 #include "string.h"
25 #include "fd.h"
26
27 /*
28 * MIN_CONSEC_GOOD_FRAMES defines how many consecutive valid MP3 frames we need
29 * to see before we decide we are looking at a real MP3 file
30 */
31 #define MIN_CONSEC_GOOD_FRAMES 4
32 #define FRAME_HEADER_SIZE 4
33 #define MIN_FRAME_SIZE 21
34
35 struct mp3header {
36 unsigned long sync;
37 unsigned int version;
38 unsigned int layer;
39 unsigned int crc;
40 unsigned int bitrate;
41 unsigned int freq;
42 unsigned int padding;
43 unsigned int mode;
44 unsigned int copyright;
45 unsigned int original;
46 unsigned int emphasis;
47 };
48
49 static const int frequencies[3][4] = {
50 {22050,24000,16000,50000}, /* MPEG 2.0 */
51 {44100,48000,32000,50000}, /* MPEG 1.0 */
52 {11025,12000,8000,50000} /* MPEG 2.5 */
53 };
54
55 static const int mp3info_bitrate[2][3][14] = {
56 { /* MPEG 2.0 */
57 {32,48,56,64,80,96,112,128,144,160,176,192,224,256}, /* layer 1 */
58 {8,16,24,32,40,48,56,64,80,96,112,128,144,160}, /* layer 2 */
59 {8,16,24,32,40,48,56,64,80,96,112,128,144,160} /* layer 3 */
60 },
61
62 { /* MPEG 1.0 */
63 {32,64,96,128,160,192,224,256,288,320,352,384,416,448}, /* layer 1 */
64 {32,48,56,64,80,96,112,128,160,192,224,256,320,384}, /* layer 2 */
65 {32,40,48,56,64,80,96,112,128,160,192,224,256,320} /* layer 3 */
66 }
67 };
68
69 static const int frame_size_index[] = {24000, 72000, 72000};
70 static const char *mode_text[] = {"stereo", "joint stereo", "dual channel", "mono", "invalid"};
71
72 #ifdef HAVE_ID3TAG
73
74 #include <id3tag.h>
75
76 static char *get_utf8(id3_ucs4_t const *string)
77 {
78 if (!string)
79 return NULL;
80 return (char *)id3_ucs4_utf8duplicate(string);
81 }
82
83 static char *get_stringlist(union id3_field *field)
84 {
85 unsigned int k, nstrings = id3_field_getnstrings(field);
86 char *result = NULL;
87
88 for (k = 0; k < nstrings; k++) {
89 char *tmp = (char *)get_utf8(id3_field_getstrings(field, k));
90 if (result) {
91 char *tmp2 = result;
92 result = make_message("%s %s", tmp2, tmp);
93 free(tmp);
94 free(tmp2);
95 } else
96 result = tmp;
97 }
98 return result;
99 }
100
101 static char *get_string(union id3_field *field)
102 {
103 id3_ucs4_t const *string = id3_field_getfullstring(field);
104
105 return get_utf8(string);
106 }
107
108 #define FOR_EACH_FIELD(f, j, fr) for (j = 0; j < (fr)->nfields && \
109 (f = id3_frame_field((fr), j)); j++)
110
111 static char *get_strings(struct id3_frame *fr)
112 {
113 int j;
114 union id3_field *field;
115
116 FOR_EACH_FIELD(field, j, fr) {
117 enum id3_field_type type = id3_field_type(field);
118
119 if (type == ID3_FIELD_TYPE_STRINGLIST)
120 return get_stringlist(field);
121 if (type == ID3_FIELD_TYPE_STRINGFULL)
122 return get_string(field);
123 }
124 return NULL;
125 }
126
127 /* this only sets values which are undefined so far */
128 static void parse_frames(struct id3_tag *id3_t, struct taginfo *tags)
129 {
130 int i;
131
132 for (i = 0; i < id3_t->nframes; i++) {
133 struct id3_frame *fr = id3_t->frames[i];
134 if (!strcmp(fr->id, ID3_FRAME_TITLE)) {
135 if (!tags->title)
136 tags->title = get_strings(fr);
137 continue;
138 }
139 if (!strcmp(fr->id, ID3_FRAME_ARTIST)) {
140 if (!tags->artist)
141 tags->artist = get_strings(fr);
142 continue;
143 }
144 if (!strcmp(fr->id, ID3_FRAME_ALBUM)) {
145 if (!tags->album)
146 tags->album = get_strings(fr);
147 continue;
148 }
149 if (!strcmp(fr->id, ID3_FRAME_YEAR)) {
150 if (!tags->year)
151 tags->year = get_strings(fr);
152 continue;
153 }
154 if (!strcmp(fr->id, ID3_FRAME_COMMENT)) {
155 if (!tags->comment)
156 tags->comment = get_strings(fr);
157 continue;
158 }
159 }
160 }
161
162 static int mp3_get_id3(unsigned char *map, size_t numbytes, __a_unused int fd,
163 struct taginfo *tags)
164 {
165 int ret = 0;
166 struct id3_tag *id3_t;
167
168 /* id3v2 tags are usually located at the beginning. */
169 id3_t = id3_tag_parse(map, numbytes);
170 if (id3_t) {
171 parse_frames(id3_t, tags);
172 ret |= 2;
173 id3_tag_delete(id3_t);
174 }
175 /* Also look for an id3v1 tag at the end of the file. */
176 if (numbytes >= 128) {
177 id3_t = id3_tag_parse(map + numbytes - 128, 128);
178 if (id3_t) {
179 parse_frames(id3_t, tags);
180 ret |= 1;
181 id3_tag_delete(id3_t);
182 }
183 }
184 return ret;
185 }
186
187 /* These helpers are not mentioned in the libid3tag header file. */
188 void id3_field_init(union id3_field *field, enum id3_field_type type);
189 void id3_field_finish(union id3_field *field);
190
191 /*
192 * Frames of type ID3_FRAME_COMMENT contain three fields of type language,
193 * string, and fullstring. The third field contains the actual comment.
194 */
195 static int set_comment_fields(struct id3_frame *fr, id3_ucs4_t *ucs4_val)
196 {
197 int ret;
198 union id3_field *field;
199
200 field = id3_frame_field(fr, 1);
201 id3_field_init(field, ID3_FIELD_TYPE_LANGUAGE);
202
203 field = id3_frame_field(fr, 2);
204 id3_field_init(field, ID3_FIELD_TYPE_STRING);
205
206 field = id3_frame_field(fr, 3);
207 id3_field_init(field, ID3_FIELD_TYPE_STRINGFULL);
208 ret = id3_field_setfullstring(field, ucs4_val);
209 if (ret < 0)
210 return -E_ID3_SETSTRING;
211 return 1;
212 }
213
214 /*
215 * UCS-4 stands for Universal Character Set where each character uses exactly
216 * 32 bits. It is also known as UTF-32, see ISO 10646.
217 *
218 * We have to use UCS-4 as an intermediate representation because the functions
219 * of libid3tag which set the tag content expect an array of UCS-4 characters.
220 * Fortunately, libid3tag contains conversion functions from and to UTF-8.
221 */
222 static int replace_tag(char const *id, const char *val, struct id3_tag *id3_t,
223 int options)
224 {
225 int ret;
226 struct id3_frame *fr;
227 union id3_field *field;
228 id3_ucs4_t *ucs4_val;
229
230 /* First, detach all frames that match the given id. */
231 while ((fr = id3_tag_findframe(id3_t, id, 0))) {
232 PARA_INFO_LOG("deleting %s frame\n", id);
233 ret = id3_tag_detachframe(id3_t, fr);
234 if (ret < 0)
235 return -E_ID3_DETACH;
236 id3_frame_delete(fr);
237 }
238 if (!val || !*val)
239 return 0;
240 fr = id3_frame_new(id);
241 PARA_DEBUG_LOG("frame desc: %s, %u fields\n", fr->description, fr->nfields);
242
243 /* Frame 0 contains the encoding. We always use UTF-8. */
244 field = id3_frame_field(fr, 0);
245 id3_field_init(field, ID3_FIELD_TYPE_TEXTENCODING);
246 ret = id3_field_settextencoding(field, ID3_FIELD_TEXTENCODING_UTF_8);
247 if (ret < 0)
248 return -E_ID3_SETENCODING;
249 /* create UCS-4 representation */
250 ucs4_val = id3_utf8_ucs4duplicate((const id3_utf8_t *)val);
251
252 if (strcmp(id, ID3_FRAME_COMMENT) == 0)
253 ret = set_comment_fields(fr, ucs4_val);
254 else {
255 /* Non-comment frames contain the value in field 1. */
256 field = id3_frame_field(fr, 1);
257 if (options & ID3_TAG_OPTION_ID3V1) {
258 id3_ucs4_t *ptr[] = {ucs4_val, NULL};
259 id3_field_init(field, ID3_FIELD_TYPE_STRINGLIST);
260 ret = id3_field_setstrings(field, 1, ptr);
261 } else {
262 id3_field_init(field, ID3_FIELD_TYPE_STRINGFULL);
263 ret = id3_field_setfullstring(field, ucs4_val);
264 }
265 }
266 free(ucs4_val);
267 if (ret < 0)
268 return -E_ID3_SETSTRING;
269
270 PARA_INFO_LOG("attaching %s frame, value: %s\n", id, val);
271 ret = id3_tag_attachframe(id3_t, fr);
272 if (ret < 0)
273 return -E_ID3_ATTACH;
274 return 1;
275 }
276
277 static int replace_tags(struct id3_tag *id3_t, struct taginfo *tags)
278 {
279 int ret, options = id3_tag_options(id3_t, 0, 0);
280
281 ret = replace_tag(ID3_FRAME_ARTIST, tags->artist, id3_t, options);
282 if (ret < 0)
283 return ret;
284 ret = replace_tag(ID3_FRAME_TITLE, tags->title, id3_t, options);
285 if (ret < 0)
286 return ret;
287 ret = replace_tag(ID3_FRAME_ALBUM, tags->album, id3_t, options);
288 if (ret < 0)
289 return ret;
290 ret = replace_tag(ID3_FRAME_YEAR, tags->year, id3_t, options);
291 if (ret < 0)
292 return ret;
293 ret = replace_tag(ID3_FRAME_COMMENT, tags->comment, id3_t, options);
294 if (ret < 0)
295 return ret;
296 return 1;
297 }
298
299 /* id3_tag_delete() does not seem to work due to refcount issues. */
300 static void free_tag(struct id3_tag *id3_t)
301 {
302 int i, j;
303
304 if (!id3_t)
305 return;
306 for (i = 0; i < id3_t->nframes; i++) {
307 struct id3_frame *fr = id3_t->frames[i];
308 for (j = 0; j < fr->nfields; j++) {
309 union id3_field *field = &fr->fields[j];
310 id3_field_finish(field);
311 }
312 free(fr);
313 }
314 free(id3_t->frames);
315 free(id3_t);
316 }
317
318 static int mp3_rewrite_tags(const char *map, size_t mapsize,
319 struct taginfo *tags, int fd, __a_unused const char *filename)
320 {
321 int ret;
322 id3_length_t old_v2size, new_v2size;
323 id3_byte_t v1_buffer[128], *v2_buffer;
324 size_t data_sz;
325 struct id3_tag *v1_tag = NULL, *v2_tag = NULL;
326
327 if (mapsize >= 128) {
328 v1_tag = id3_tag_parse((const id3_byte_t *)map + mapsize - 128,
329 128);
330 if (v1_tag) {
331 PARA_NOTICE_LOG("replacing id3v1 tag\n");
332 ret = replace_tags(v1_tag, tags);
333 if (ret < 0)
334 goto out;
335 id3_tag_render(v1_tag, v1_buffer);
336 }
337 }
338 old_v2size = 0;
339 v2_tag = id3_tag_parse((const id3_byte_t *)map, mapsize);
340 if (v2_tag) {
341 PARA_NOTICE_LOG("replacing id3v2 tag\n");
342 old_v2size = v2_tag->paddedsize;
343 } else {
344 PARA_NOTICE_LOG("adding id3v2 tag\n");
345 v2_tag = id3_tag_new();
346 assert(v2_tag);
347 }
348 /*
349 * Turn off all options to avoid creating an extended header. id321
350 * does not understand it.
351 */
352 id3_tag_options(v2_tag, ~0U, 0);
353 ret = replace_tags(v2_tag, tags);
354 if (ret < 0)
355 goto out;
356 new_v2size = id3_tag_render(v2_tag, NULL);
357 v2_buffer = para_malloc(new_v2size);
358 id3_tag_render(v2_tag, v2_buffer);
359 PARA_INFO_LOG("writing v2 tag (%lu bytes)\n", new_v2size);
360 ret = write_all(fd, (char *)v2_buffer, new_v2size);
361 free(v2_buffer);
362 if (ret < 0)
363 goto out;
364 data_sz = mapsize - old_v2size;
365 if (v1_tag && data_sz >= 128)
366 data_sz -= 128;
367 PARA_INFO_LOG("writing data part (%zu bytes)\n", data_sz);
368 ret = write_all(fd, map + old_v2size, data_sz);
369 if (ret < 0)
370 goto out;
371 if (v1_tag) {
372 PARA_INFO_LOG("writing v1 tag\n");
373 ret = write_all(fd, (char *)v1_buffer, 128);
374 }
375 out:
376 free_tag(v1_tag);
377 free_tag(v2_tag);
378 return ret;
379 }
380
381 #else /* HAVE_ID3TAG */
382
383 /*
384 * Remove trailing whitespace from the end of a string
385 */
386 static char *unpad(char *string)
387 {
388 char *pos = string + strlen(string) - 1;
389 while (para_isspace(pos[0]))
390 (pos--)[0] = 0;
391 return string;
392 }
393
394 static int mp3_get_id3(unsigned char *map, size_t numbytes, __a_unused int fd,
395 struct taginfo *tags)
396 {
397 char title[31], artist[31], album[31], year[5], comment[31];
398 off_t fpos;
399
400 if (numbytes < 128 || strncmp("TAG", (char *)map + numbytes - 128, 3)) {
401 PARA_DEBUG_LOG("no id3 v1 tag\n");
402 return 0;
403 }
404 fpos = numbytes - 125;
405 memcpy(title, map + fpos, 30);
406 fpos += 30;
407 title[30] = '\0';
408 memcpy(artist, map + fpos, 30);
409 fpos += 30;
410 artist[30] = '\0';
411 memcpy(album, map + fpos, 30);
412 fpos += 30;
413 album[30] = '\0';
414 memcpy(year, map + fpos, 4);
415 fpos += 4;
416 year[4] = '\0';
417 memcpy(comment, map + fpos, 30);
418 comment[30] = '\0';
419 unpad(title);
420 unpad(artist);
421 unpad(album);
422 unpad(year);
423 unpad(comment);
424 tags->artist = para_strdup(artist);
425 tags->title = para_strdup(title);
426 tags->year = para_strdup(year);
427 tags->album = para_strdup(album);
428 tags->comment = para_strdup(comment);
429 return 1;
430 }
431 #endif /* HAVE_ID3TAG */
432
433 static int header_frequency(struct mp3header *h)
434 {
435 if (h->version > 2 || h->freq > 3)
436 return -E_HEADER_FREQ;
437 return frequencies[h->version][h->freq];
438 }
439
440 static const char *header_mode(struct mp3header *h)
441 {
442 if (h->mode > 4)
443 h->mode = 4; /* invalid */
444 return mode_text[h->mode];
445 }
446
447 static int header_channels(struct mp3header *h)
448 {
449 if (h->mode > 3)
450 return 0;
451 if (h->mode < 3)
452 return 2;
453 return 1;
454 }
455
456 static int header_bitrate(struct mp3header *h)
457 {
458 if (!h->layer || h->layer > 3 || h->bitrate > 14 || !h->bitrate)
459 return -E_HEADER_BITRATE;
460 return mp3info_bitrate[h->version & 1][3 - h->layer][h->bitrate - 1];
461 }
462
463 static int frame_length(struct mp3header *header)
464 {
465 int hb, hf = header_frequency(header);
466
467 if (hf < 0)
468 return hf;
469 hb = header_bitrate(header);
470 if (hb < 0)
471 return hb;
472 if (header->sync != 0xFFE || header->layer > 3)
473 return -E_FRAME;
474 return frame_size_index[3 - header->layer] *
475 ((header->version & 1) + 1) * hb / hf
476 + header->padding;
477 }
478
479 static int compare_headers(struct mp3header *h1,struct mp3header *h2)
480 {
481 if ((*(unsigned int*)h1) == (*(unsigned int*)h2))
482 return 1;
483 if ((h1->version == h2->version) &&
484 (h1->layer == h2->layer) &&
485 (h1->crc == h2->crc) &&
486 (h1->freq == h2->freq) &&
487 (h1->mode == h2->mode) &&
488 (h1->copyright == h2->copyright) &&
489 (h1->original == h2->original) &&
490 (h1->emphasis == h2->emphasis))
491 return 1;
492 return 0;
493 }
494
495 /*
496 * get next MP3 frame header.
497 *
498 * On success, the header frame length is returned and the given header
499 * structure that is filled in. A return value of zero means that we did not
500 * retrieve a valid frame header, and a negative return value indicates an
501 * error.
502 */
503 static int get_header(unsigned char *map, size_t numbytes, off_t *fpos,
504 struct mp3header *header)
505 {
506 int fl, ret;
507
508 if (*fpos + FRAME_HEADER_SIZE > numbytes) {
509 *fpos = numbytes - 1;
510 header->sync = 0;
511 return 0;
512 }
513 header->layer = (map[*fpos + 1] >> 1) & 3;
514 header->sync = (((int)map[*fpos]<<4) | ((int)(map[*fpos + 1]&0xE0)>>4));
515 if (map[*fpos + 1] & 0x10)
516 header->version = (map[*fpos + 1] >> 3) & 1;
517 else
518 header->version = 2;
519 if ((header->sync != 0xFFE) || (header->layer != 1)) {
520 ret = 0;
521 header->sync = 0;
522 goto out;
523 }
524 header->crc = map[*fpos + 1] & 1;
525 header->bitrate = (map[*fpos + 2] >> 4) & 0x0F;
526 header->freq = (map[*fpos + 2] >> 2) & 0x3;
527 header->padding = (map[*fpos + 2] >>1) & 0x1;
528 header->mode = (map[*fpos + 3] >> 6) & 0x3;
529 fl = frame_length(header);
530 ret = (fl >= MIN_FRAME_SIZE)? fl : -E_FRAME_LENGTH;
531 out:
532 *fpos += FRAME_HEADER_SIZE;
533 return ret;
534 }
535
536 /*
537 * find the next mp3 header
538 *
539 * Return the length of the next frame header or zero if the end of the file is
540 * reached.
541 */
542 static int mp3_seek_next_header(unsigned char *map, size_t numbytes, off_t *fpos,
543 struct mp3header *result)
544 {
545 int k, l = 0, first_len;
546 struct mp3header h, h2;
547 long valid_start = 0;
548
549 for (; *fpos < numbytes; (*fpos)++) {
550 if (map[*fpos] != 0xff)
551 continue;
552 valid_start = *fpos;
553 first_len = get_header(map, numbytes, fpos, &h);
554 if (first_len <= 0)
555 continue;
556 *fpos += first_len - FRAME_HEADER_SIZE;
557 for (k = 1; k < MIN_CONSEC_GOOD_FRAMES; k++) {
558 if ((l = get_header(map, numbytes, fpos, &h2)) <= 0)
559 break;
560 if (!compare_headers(&h, &h2))
561 break;
562 *fpos += l - FRAME_HEADER_SIZE;
563 }
564 if (k == MIN_CONSEC_GOOD_FRAMES) {
565 *fpos = valid_start;
566 *result = h2;
567 return first_len;
568 }
569 }
570 return 0;
571 }
572
573 static int find_valid_start(unsigned char *map, size_t numbytes, off_t *fpos,
574 struct mp3header *header)
575 {
576 int frame_len;
577
578 frame_len = get_header(map, numbytes, fpos, header);
579 if (frame_len < 0)
580 return frame_len;
581 if (!frame_len) {
582 frame_len = mp3_seek_next_header(map, numbytes, fpos, header);
583 if (frame_len <= 0)
584 return frame_len;
585 } else
586 *fpos -= FRAME_HEADER_SIZE;
587 if (frame_len <= 1)
588 return -E_FRAME_LENGTH;
589 return frame_len;
590 }
591
592 static int mp3_read_info(unsigned char *map, size_t numbytes, int fd,
593 struct afh_info *afhi)
594 {
595 uint64_t freq_sum = 0, br_sum = 0;
596 int fl = 0, ret, len = 0, old_br = -1, vbr = 0;
597 struct timeval total_time = {0, 0};
598 unsigned chunk_table_size = 1000; /* gets increased on demand */
599 off_t fpos = 0;
600 struct mp3header header;
601 const char *tag_versions[] = {"no", "id3v1", "id3v2", "id3v1+id3v2"};
602
603 afhi->chunks_total = 0;
604 afhi->chunk_table = para_malloc(chunk_table_size * sizeof(uint32_t));
605 while (1) {
606 int freq, br;
607 struct timeval tmp, cct; /* current chunk time */
608 fpos += len;
609 len = find_valid_start(map, numbytes, &fpos, &header);
610 if (len <= 0) {
611 size_t end;
612 ret = -E_MP3_INFO;
613 if (!afhi->chunks_total)
614 goto err_out;
615 end = afhi->chunk_table[afhi->chunks_total - 1] + fl;
616 afhi->chunk_table[afhi->chunks_total]
617 = PARA_MIN(end, numbytes);
618 break;
619 }
620 ret = header_frequency(&header);
621 if (ret < 0)
622 continue;
623 freq = ret;
624 ret = header_bitrate(&header);
625 if (ret < 0)
626 continue;
627 br = ret;
628 ret = frame_length(&header);
629 if (ret < 0)
630 continue;
631 fl = ret;
632 tmp.tv_sec = fl - header.padding;
633 tmp.tv_usec = 0;
634 tv_divide(br * 125, &tmp, &cct);
635 tv_add(&cct, &total_time, &tmp);
636 total_time = tmp;
637 if (afhi->chunks_total >= chunk_table_size) {
638 chunk_table_size *= 2;
639 afhi->chunk_table = para_realloc(afhi->chunk_table,
640 chunk_table_size * sizeof(uint32_t));
641 }
642 afhi->chunk_table[afhi->chunks_total] = fpos;
643 afhi->chunks_total++;
644 freq_sum += freq;
645 br_sum += br;
646 if (afhi->chunks_total != 1 && old_br != br)
647 vbr = 1;
648 old_br = br;
649 }
650 ret = -E_MP3_INFO;
651 if (!freq_sum || !br_sum)
652 goto err_out;
653 afhi->bitrate = br_sum / afhi->chunks_total;
654 afhi->frequency = freq_sum / afhi->chunks_total;
655 afhi->channels = header_channels(&header);
656 afhi->seconds_total = (tv2ms(&total_time) + 500) / 1000;
657 tv_divide(afhi->chunks_total, &total_time, &afhi->chunk_tv);
658 PARA_DEBUG_LOG("%" PRIu32 "chunks, each %lums\n", afhi->chunks_total,
659 tv2ms(&afhi->chunk_tv));
660 ret = mp3_get_id3(map, numbytes, fd, &afhi->tags);
661 afhi->techinfo = make_message("%cbr, %s, %s tags", vbr? 'v' : 'c',
662 header_mode(&header), tag_versions[ret]);
663 return 1;
664 err_out:
665 free(afhi->chunk_table);
666 return ret;
667 }
668
669 /*
670 * Read mp3 information from audio file
671 */
672 static int mp3_get_file_info(char *map, size_t numbytes, int fd,
673 struct afh_info *afhi)
674 {
675 int ret;
676
677 ret = mp3_read_info((unsigned char *)map, numbytes, fd, afhi);
678 if (ret < 0)
679 return ret;
680 if (afhi->seconds_total < 2 || !afhi->chunks_total)
681 return -E_MP3_INFO;
682 return 1;
683 }
684
685 static const char * const mp3_suffixes[] = {"mp3", NULL};
686
687 /**
688 * the init function of the mp3 audio format handler
689 *
690 * \param afh pointer to the struct to initialize
691 */
692 void mp3_init(struct audio_format_handler *afh)
693 {
694 afh->get_file_info = mp3_get_file_info;
695 afh->suffixes = mp3_suffixes;
696 #ifdef HAVE_LIBID3TAG
697 afh->rewrite_tags = mp3_rewrite_tags;
698 #endif /* HAVE_LIBID3TAG */
699 }