Merge branch 'refs/heads/t/si_conversion'
[paraslash.git] / afh_common.c
1 /*
2 * Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file afh_common.c Common audio format handler functions. */
8
9 #include <sys/mman.h> /* mmap */
10 #include <sys/types.h>
11 #include <regex.h>
12
13 #include "para.h"
14 #include "error.h"
15 #include "string.h"
16 #include "afh.h"
17
18 typedef void afh_init_func(struct audio_format_handler *);
19
20 /*
21 * Declaration of the audio format handler init functions.
22 *
23 * These symbols are referenced in the afl array below.
24 *
25 * Most audio format handlers depend on an external library and are not
26 * compiled in if the library is not installed. Hence it is well possible that
27 * not all of these functions are defined. It does not hurt to declare them
28 * anyway, and this avoids another set of ifdefs.
29 */
30 extern afh_init_func mp3_afh_init, ogg_afh_init, aac_afh_init, wma_afh_init,
31 spx_afh_init, flac_afh_init, opus_afh_init;
32
33 /** The list of all status items */
34 const char *status_item_list[] = {STATUS_ITEMS};
35
36 /**
37 * The list of supported audio formats.
38 *
39 * We always define the full array of audio formats even if some audio formats
40 * were not compiled in. This is because for each audio file the number of its
41 * audio format is stored in the database. We don't want these numbers to become
42 * stale just because the user installed a new version of paraslash that
43 * supports a different set of audio formats.
44 *
45 * It can still be easily detected whether an audio format is compiled in by
46 * checking if the init function pointer is not \p NULL.
47 */
48 static struct audio_format_handler afl[] = {
49 {
50 .name = "mp3",
51 .init = mp3_afh_init,
52 },
53 {
54 .name = "ogg",
55 #if defined(HAVE_OGG) && defined(HAVE_VORBIS)
56 .init = ogg_afh_init,
57 #endif
58 },
59 {
60 .name = "aac",
61 #if defined(HAVE_FAAD)
62 .init = aac_afh_init,
63 #endif
64 },
65 {
66 .name = "wma",
67 .init = wma_afh_init,
68 },
69 {
70 .name = "spx",
71 #if defined(HAVE_OGG) && defined(HAVE_SPEEX)
72 .init = spx_afh_init,
73 #endif
74 },
75 {
76 .name = "flac",
77 #if defined(HAVE_OGG) && defined(HAVE_FLAC)
78 .init = flac_afh_init,
79 #endif
80 },
81 {
82 .name = "opus",
83 #if defined(HAVE_OGG) && defined(HAVE_OPUS)
84 .init = opus_afh_init,
85 #endif
86 },
87 {
88 .name = NULL,
89 }
90 };
91
92 static inline int next_audio_format(int format)
93 {
94 for (;;) {
95 if (!afl[format].name)
96 return format;
97 format++;
98 if (afl[format].init)
99 return format;
100 }
101 }
102
103 /** Iterate over each supported audio format. */
104 #define FOR_EACH_AUDIO_FORMAT(i) for (i = 0; afl[i].name; i = next_audio_format(i))
105
106 /**
107 * Call the init function of each supported audio format handler.
108 */
109 void afh_init(void)
110 {
111 int i;
112
113 PARA_NOTICE_LOG("supported audio formats: %s\n", AUDIO_FORMAT_HANDLERS);
114 FOR_EACH_AUDIO_FORMAT(i) {
115 PARA_INFO_LOG("initializing %s handler\n",
116 audio_format_name(i));
117 afl[i].init(&afl[i]);
118 }
119 }
120
121 /**
122 * Tell whether an audio format handler provides chunk tables.
123 *
124 * Each audio format handler either provides a chunk table or supports dynamic
125 * chunks.
126 *
127 * \param audio_format_id Offset in the afl array.
128 *
129 * \return True if dynamic chunks are supported, false if the audio format
130 * handler provides chunk tables.
131 */
132 bool afh_supports_dynamic_chunks(int audio_format_id)
133 {
134 return afl[audio_format_id].get_chunk;
135 }
136
137 /**
138 * Guess the audio format judging from filename.
139 *
140 * \param name The filename.
141 *
142 * \return This function returns \p -E_AUDIO_FORMAT if it has no idea what kind
143 * of audio file this might be. Otherwise the (non-negative) number of the
144 * audio format is returned.
145 */
146 int guess_audio_format(const char *name)
147 {
148 int i,j, len = strlen(name);
149
150 FOR_EACH_AUDIO_FORMAT(i) {
151 for (j = 0; afl[i].suffixes[j]; j++) {
152 const char *p = afl[i].suffixes[j];
153 int plen = strlen(p);
154 if (len < plen + 1)
155 continue;
156 if (name[len - plen - 1] != '.')
157 continue;
158 if (strcasecmp(name + len - plen, p))
159 continue;
160 // PARA_DEBUG_LOG("might be %s\n", audio_format_name(i));
161 return i;
162 }
163 }
164 return -E_AUDIO_FORMAT;
165 }
166
167 /**
168 * Get the name of the given audio format.
169 *
170 * \param i The audio format number.
171 *
172 * \return This returns a pointer to statically allocated memory so it
173 * must not be freed by the caller.
174 */
175 const char *audio_format_name(int i)
176 {
177 if (i < 0 || i >= ARRAY_SIZE(afl) - 1)
178 return "???";
179 return afl[i].name;
180 }
181
182 static int get_file_info(int format, const char *path, char *data,
183 size_t size, int fd, struct afh_info *afhi)
184 {
185 int ret;
186 const char *fmt = audio_format_name(format);
187
188 memset(afhi, 0, sizeof(*afhi));
189 ret = afl[format].get_file_info(data, size, fd, afhi);
190 if (ret < 0) {
191 PARA_WARNING_LOG("%s: %s format not detected: %s\n",
192 path, fmt, para_strerror(-ret));
193 return ret;
194 }
195 PARA_NOTICE_LOG("%s: detected %s format\n", path, fmt);
196 return format;
197 }
198
199 /**
200 * Call get_file_info() to obtain an afhi structure.
201 *
202 * \param path The full path of the audio file.
203 * \param data Pointer to the contents of the (mapped) file.
204 * \param size The file size in bytes.
205 * \param fd The open file descriptor.
206 * \param afhi Result pointer.
207 *
208 * \return The number of the audio format on success, \p -E_AUDIO_FORMAT if no
209 * compiled in audio format handler is able to handler the file.
210 *
211 * This function tries to find an audio format handler that can interpret the
212 * file given by \a data and \a size.
213 *
214 * It first tries to determine the audio format from the filename given by \a
215 * path. If this doesn't work, all other audio format handlers are tried until
216 * one is found that can handle the file.
217 */
218 int compute_afhi(const char *path, char *data, size_t size, int fd,
219 struct afh_info *afhi)
220 {
221 int ret, i, format;
222
223 format = guess_audio_format(path);
224 if (format >= 0) {
225 ret = get_file_info(format, path, data, size, fd, afhi);
226 if (ret >= 0)
227 goto success;
228 }
229 FOR_EACH_AUDIO_FORMAT(i) {
230 if (i == format) /* we already tried this one to no avail */
231 continue;
232 ret = get_file_info(i, path, data, size, fd, afhi);
233 if (ret >= 0)
234 goto success;
235 }
236 return -E_AUDIO_FORMAT;
237 success:
238 if (!afhi->techinfo)
239 afhi->techinfo = para_strdup(NULL);
240 if (!afhi->tags.artist)
241 afhi->tags.artist = para_strdup(NULL);
242 if (!afhi->tags.title)
243 afhi->tags.title = para_strdup(NULL);
244 if (!afhi->tags.year)
245 afhi->tags.year = para_strdup(NULL);
246 if (!afhi->tags.album)
247 afhi->tags.album = para_strdup(NULL);
248 if (!afhi->tags.comment)
249 afhi->tags.comment = para_strdup(NULL);
250 PARA_DEBUG_LOG("techinfo: %s\n", afhi->techinfo);
251 PARA_DEBUG_LOG("artist: %s\n", afhi->tags.artist);
252 PARA_DEBUG_LOG("title: %s\n", afhi->tags.title);
253 PARA_DEBUG_LOG("year: %s\n", afhi->tags.year);
254 PARA_DEBUG_LOG("album: %s\n", afhi->tags.album);
255 PARA_DEBUG_LOG("comment: %s\n", afhi->tags.comment);
256 return ret;
257 }
258
259 /**
260 * Deallocate the contents of an afh_info structure.
261 *
262 * \param afhi The structure to clear.
263 *
264 * This only frees the memory the various pointer fields of \a afhi point to.
265 * It does *not* free \a afhi itself.
266 */
267 void clear_afhi(struct afh_info *afhi)
268 {
269 if (!afhi)
270 return;
271 free(afhi->chunk_table);
272 free(afhi->techinfo);
273 free(afhi->tags.artist);
274 free(afhi->tags.title);
275 free(afhi->tags.year);
276 free(afhi->tags.album);
277 free(afhi->tags.comment);
278 }
279
280 static inline size_t get_chunk_len(long unsigned chunk_num,
281 const struct afh_info *afhi)
282 {
283 return afhi->chunk_table[chunk_num + 1] - afhi->chunk_table[chunk_num];
284 }
285
286 /**
287 * Get one chunk of audio data.
288 *
289 * This implicitly calls the ->open method of the audio format handler at the
290 * first call.
291 *
292 * \param chunk_num The number of the chunk to get.
293 * \param afhi Describes the audio file.
294 * \param audio_format_id Determines the afh.
295 * \param map The memory mapped audio file.
296 * \param mapsize Passed to the afh's ->open() method.
297 * \param buf Result pointer.
298 * \param len The length of the chunk in bytes.
299 * \param afh_context Value/result, determines whether ->open() is called.
300 *
301 * Upon return, \a buf will point so memory inside \a map. The returned buffer
302 * must therefore not be freed by the caller.
303 *
304 * \return Standard.
305 */
306 __must_check int afh_get_chunk(long unsigned chunk_num, struct afh_info *afhi,
307 uint8_t audio_format_id, const void *map, size_t mapsize,
308 const char **buf, size_t *len, void **afh_context)
309 {
310 struct audio_format_handler *afh = afl + audio_format_id;
311
312 if (afh_supports_dynamic_chunks(audio_format_id)) {
313 int ret;
314
315 if (!*afh_context) {
316 ret = afh->open(map, mapsize, afh_context);
317 if (ret < 0)
318 return ret;
319 }
320 ret = afl[audio_format_id].get_chunk(chunk_num, *afh_context,
321 buf, len);
322 if (ret < 0) {
323 afh->close(*afh_context);
324 *afh_context = NULL;
325 }
326 return ret;
327 } else {
328 size_t pos = afhi->chunk_table[chunk_num];
329 *buf = map + pos;
330 *len = get_chunk_len(chunk_num, afhi);
331 return 0;
332 }
333 }
334
335 /**
336 * Deallocate resources allocated due to dynamic chunk handling.
337 *
338 * This function should be called if afh_get_chunk() was called at least once.
339 * It is OK to call it even for audio formats which do not support dynamic
340 * chunks, in which case the function does nothing.
341 *
342 * \param afh_context As returned from the ->open method of the afh.
343 * \param audio_format_id Determines the afh.
344 */
345 void afh_close(void *afh_context, uint8_t audio_format_id)
346 {
347 struct audio_format_handler *afh = afl + audio_format_id;
348
349 if (!afh_supports_dynamic_chunks(audio_format_id))
350 return;
351 if (!afh->close)
352 return;
353 if (!afh_context)
354 return;
355 afh->close(afh_context);
356 }
357
358 /**
359 * Find a suitable start chunk.
360 *
361 * \param approx_chunk_num Upper bound for the chunk number to return.
362 * \param afhi Needed for the chunk table.
363 * \param audio_format_id Determines the afh.
364 *
365 * \return For audio format handlers which support dynamic chunks, the function
366 * returns the given chunk number. Otherwise it returns the first non-empty
367 * chunk <= \a approx_chunk_num.
368 *
369 * \sa \ref afh_get_chunk().
370 */
371 int32_t afh_get_start_chunk(int32_t approx_chunk_num,
372 const struct afh_info *afhi, uint8_t audio_format_id)
373 {
374 int32_t k;
375
376 if (afh_supports_dynamic_chunks(audio_format_id))
377 return approx_chunk_num;
378
379 for (k = PARA_MAX(0, approx_chunk_num); k >= 0; k--)
380 if (get_chunk_len(k, afhi) > 0)
381 return k;
382 return 0;
383 }
384
385 /**
386 * Get the header of an audio file.
387 *
388 * \param afhi The audio file handler data describing the file.
389 * \param audio_format_id Determines the audio format handler.
390 * \param map The data of the audio file.
391 * \param mapsize The amount of bytes of the mmapped audio file.
392 * \param buf The length of the header is stored here.
393 * \param len Points to a buffer containing the header on return.
394 *
395 * This function sets \a buf to \p NULL and \a len to zero if \a map or \a
396 * afhi is \p NULL, or if the current audio format does not need special
397 * header treatment.
398 *
399 * Otherwise, it is checked whether the audio format handler given by
400 * \a audio_format_id defines a ->get_header() method. If it does, this
401 * method is called to obtain the header. If ->get_header() is \p NULL,
402 * a reference to the first chunk of the audio file is returned.
403 *
404 * Once the header is no longer needed, the caller must call \ref
405 * afh_free_header() to free the resources allocated by this function.
406 */
407 void afh_get_header(struct afh_info *afhi, uint8_t audio_format_id,
408 void *map, size_t mapsize, char **buf, size_t *len)
409 {
410 struct audio_format_handler *afh = afl + audio_format_id;
411
412 if (!map || !afhi || !afhi->header_len) {
413 *buf = NULL;
414 *len = 0;
415 return;
416 }
417 if (!afh->get_header) {
418 *len = afhi->header_len;
419 *buf = map;
420 return;
421 }
422 afh->get_header(map, mapsize, buf, len);
423 }
424
425 /**
426 * Deallocate any resources obtained from afh_get_header().
427 *
428 * \param header_buf Pointer obtained via afh_get_header().
429 * \param audio_format_id Determines the audio format handler.
430 */
431 void afh_free_header(char *header_buf, uint8_t audio_format_id)
432 {
433 struct audio_format_handler *afh = afl + audio_format_id;
434
435 if (afh->get_header)
436 free(header_buf);
437 }
438
439 /**
440 * Pretty-print the contents of a struct afh_info into a buffer.
441 *
442 * \param audio_format_num The audio format number.
443 * \param afhi Pointer to the structure that contains the information.
444 * \param result Pretty-printed ahfi is here after the call.
445 *
446 * The \a result buffer is dynamically allocated and should be freed by the
447 * caller.
448 *
449 * \return The number of bytes. This function never fails.
450 */
451 unsigned afh_get_afhi_txt(int audio_format_num, struct afh_info *afhi, char **result)
452 {
453 return xasprintf(result, "%s: %dkbit/s\n" /* bitrate */
454 "%s: %s\n" /* format */
455 "%s: %dHz\n" /* frequency */
456 "%s: %d\n" /* channels */
457 "%s: %" PRIu32 "\n" /* seconds total */
458 "%s: %lu: %lu\n" /* chunk time */
459 "%s: %" PRIu32 "\n" /* num chunks */
460 "%s: %" PRIu32 "\n" /* max chunk size */
461 "%s: %s\n" /* techinfo */
462 "%s: %s\n" /* artist */
463 "%s: %s\n" /* title */
464 "%s: %s\n" /* year */
465 "%s: %s\n" /* album */
466 "%s: %s\n", /* comment */
467 status_item_list[SI_bitrate], afhi->bitrate,
468 status_item_list[SI_format], audio_format_name(audio_format_num),
469 status_item_list[SI_frequency], afhi->frequency,
470 status_item_list[SI_channels], afhi->channels,
471 status_item_list[SI_seconds_total], afhi->seconds_total,
472 status_item_list[SI_chunk_time], (long unsigned)afhi->chunk_tv.tv_sec,
473 (long unsigned)afhi->chunk_tv.tv_usec,
474 status_item_list[SI_num_chunks], afhi->chunks_total,
475 status_item_list[SI_max_chunk_size], afhi->max_chunk_size,
476 status_item_list[SI_techinfo], afhi->techinfo? afhi->techinfo : "",
477 status_item_list[SI_artist], afhi->tags.artist? afhi->tags.artist : "",
478 status_item_list[SI_title], afhi->tags.title? afhi->tags.title : "",
479 status_item_list[SI_year], afhi->tags.year? afhi->tags.year : "",
480 status_item_list[SI_album], afhi->tags.album? afhi->tags.album : "",
481 status_item_list[SI_comment], afhi->tags.comment? afhi->tags.comment : ""
482 );
483 }
484
485 /**
486 * Determine the maximal chunk size by investigating the chunk table.
487 *
488 * \param afhi Value/result.
489 *
490 * This function iterates over the chunk table and sets ->max_chunk_size
491 * accordingly. The function exists only for backward compatibility since as of
492 * version 0.6.0, para_server stores the maximal chunk size in its database.
493 * This function is only called if the database value is zero, indicating that
494 * the file was added by an older server version.
495 */
496 void set_max_chunk_size(struct afh_info *afhi)
497 {
498 uint32_t n, max = 0, old = 0;
499
500 for (n = 0; n <= afhi->chunks_total; n++) {
501 uint32_t val = afhi->chunk_table[n];
502 /*
503 * If the first chunk is the header, do not consider it for the
504 * calculation of the largest chunk size.
505 */
506 if (n == 0 || (n == 1 && afhi->header_len > 0)) {
507 old = val;
508 continue;
509 }
510 max = PARA_MAX(max, val - old);
511 old = val;
512 }
513 afhi->max_chunk_size = max;
514 }
515
516 /**
517 * Create a copy of the given file with altered meta tags.
518 *
519 * \param audio_format_id Specifies the audio format.
520 * \param map The (read-only) memory map of the input file.
521 * \param mapsize The size of the input file in bytes.
522 * \param tags The new tags.
523 * \param output_fd Altered file is created using this file descriptor.
524 * \param filename The name of the temporary output file.
525 *
526 * This calls the ->rewrite_tags method of the audio format handler associated
527 * with \a audio_format_id to create a copy of the memory-mapped file given
528 * by \a map and \a mapsize, but with altered tags according to \a tags. If
529 * the audio format handler for \a audio_format_id lacks this optional method,
530 * the function returns (the paraslash error code of) \p ENOTSUP.
531 *
532 * \return Standard.
533 */
534 int afh_rewrite_tags(int audio_format_id, void *map, size_t mapsize,
535 struct taginfo *tags, int output_fd, const char *filename)
536 {
537 struct audio_format_handler *afh = afl + audio_format_id;
538
539 if (!afh->rewrite_tags)
540 return -ERRNO_TO_PARA_ERROR(ENOTSUP);
541 return afh->rewrite_tags(map, mapsize, tags, output_fd, filename);
542 }