Never start playback at an empty chunk.
[paraslash.git] / afh_common.c
1 /*
2 * Copyright (C) 1997-2014 Andre Noll <maan@systemlinux.org>
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 /* The mp3 audio format handler does not need any libs. */
19 void mp3_init(struct audio_format_handler *);
20
21 #ifdef HAVE_OGGVORBIS
22 void ogg_init(struct audio_format_handler *);
23 #endif
24 #ifdef HAVE_FAAD
25 void aac_afh_init(struct audio_format_handler *);
26 #endif
27 #ifdef HAVE_SPEEX
28 void spx_afh_init(struct audio_format_handler *);
29 #endif
30 #ifdef HAVE_FLAC
31 void flac_afh_init(struct audio_format_handler *);
32 #endif
33
34 #ifdef HAVE_OPUS
35 void opus_afh_init(struct audio_format_handler *);
36 #endif
37
38 void wma_afh_init(struct audio_format_handler *);
39
40 /** The list of all status items */
41 const char *status_item_list[] = {STATUS_ITEM_ARRAY};
42
43 /**
44 * The list of supported audio formats.
45 *
46 * We always define the full array of audio formats even if some audio formats
47 * were not compiled in. This is because for each audio file the number of its
48 * audio format is stored in the database. We don't want that numbers to become
49 * stale just because the user installed a new version of paraslash that
50 * supports a different set of audio formats.
51 *
52 * It can still be easily detected whether an audio format is compiled in by
53 * checking if the init function pointer is not \p NULL.
54 */
55 static struct audio_format_handler afl[] = {
56 {
57 .name = "mp3",
58 .init = mp3_init,
59 },
60 {
61 .name = "ogg",
62 #ifdef HAVE_OGGVORBIS
63 .init = ogg_init,
64 #endif
65 },
66 {
67 .name = "aac",
68 #ifdef HAVE_FAAD
69 .init = aac_afh_init,
70 #endif
71 },
72 {
73 .name = "wma",
74 .init = wma_afh_init,
75 },
76 {
77 .name = "spx",
78 #ifdef HAVE_SPEEX
79 .init = spx_afh_init,
80 #endif
81 },
82 {
83 .name = "flac",
84 #ifdef HAVE_FLAC
85 .init = flac_afh_init,
86 #endif
87 },
88 {
89 .name = "opus",
90 #ifdef HAVE_OPUS
91 .init = opus_afh_init,
92 #endif
93 },
94 {
95 .name = NULL,
96 }
97 };
98
99 static inline int next_audio_format(int format)
100 {
101 for (;;) {
102 if (!afl[format].name)
103 return format;
104 format++;
105 if (afl[format].init)
106 return format;
107 }
108
109 }
110
111 /** Iterate over each supported audio format. */
112 #define FOR_EACH_AUDIO_FORMAT(i) for (i = 0; afl[i].name; i = next_audio_format(i))
113
114 /**
115 * Call the init function of each supported audio format handler.
116 */
117 void afh_init(void)
118 {
119 int i;
120
121 PARA_INFO_LOG("supported audio formats: %s\n", AUDIO_FORMAT_HANDLERS);
122 FOR_EACH_AUDIO_FORMAT(i) {
123 PARA_NOTICE_LOG("initializing %s handler\n",
124 audio_format_name(i));
125 afl[i].init(&afl[i]);
126 }
127 }
128
129 /**
130 * Guess the audio format judging from filename.
131 *
132 * \param name The filename.
133 *
134 * \return This function returns \p -E_AUDIO_FORMAT if it has no idea what kind
135 * of audio file this might be. Otherwise the (non-negative) number of the
136 * audio format is returned.
137 */
138 int guess_audio_format(const char *name)
139 {
140 int i,j, len = strlen(name);
141
142 FOR_EACH_AUDIO_FORMAT(i) {
143 for (j = 0; afl[i].suffixes[j]; j++) {
144 const char *p = afl[i].suffixes[j];
145 int plen = strlen(p);
146 if (len < plen + 1)
147 continue;
148 if (name[len - plen - 1] != '.')
149 continue;
150 if (strcasecmp(name + len - plen, p))
151 continue;
152 // PARA_DEBUG_LOG("might be %s\n", audio_format_name(i));
153 return i;
154 }
155 }
156 return -E_AUDIO_FORMAT;
157 }
158
159 /**
160 * Call get_file_info() to obtain an afhi structure.
161 *
162 * \param path The full path of the audio file.
163 * \param data Pointer to the contents of the (mapped) file.
164 * \param size The file size in bytes.
165 * \param fd The open file descriptor.
166 * \param afhi Result pointer.
167 *
168 * \return The number of the audio format on success, \p -E_AUDIO_FORMAT if no
169 * compiled in audio format handler is able to handler the file.
170 *
171 * This function tries to find an audio format handler that can interpret the
172 * file given by \a data and \a size.
173 *
174 * It first tries to determine the audio format from the filename given by \a
175 * path. If this doesn't work, all other audio format handlers are tried until
176 * one is found that can handle the file.
177 */
178 int compute_afhi(const char *path, char *data, size_t size, int fd,
179 struct afh_info *afhi)
180 {
181 int ret, i, format;
182
183 afhi->header_len = 0;
184 afhi->techinfo = NULL;
185 afhi->tags.artist = NULL;
186 afhi->tags.title = NULL;
187 afhi->tags.year = NULL;
188 afhi->tags.album = NULL;
189 afhi->tags.comment = NULL;
190 format = guess_audio_format(path);
191
192 if (format >= 0) {
193 ret = afl[format].get_file_info(data, size, fd, afhi);
194 if (ret >= 0) {
195 ret = format;
196 goto success;
197 }
198 }
199 FOR_EACH_AUDIO_FORMAT(i) {
200 if (i == format) /* we already tried this one to no avail */
201 continue;
202 ret = afl[i].get_file_info(data, size, fd, afhi);
203 if (ret >= 0) {
204 ret = i;
205 goto success;
206 }
207 PARA_WARNING_LOG("%s\n", para_strerror(-ret));
208 }
209 return -E_AUDIO_FORMAT;
210 success:
211 if (!afhi->techinfo)
212 afhi->techinfo = para_strdup(NULL);
213 if (!afhi->tags.artist)
214 afhi->tags.artist = para_strdup(NULL);
215 if (!afhi->tags.title)
216 afhi->tags.title = para_strdup(NULL);
217 if (!afhi->tags.year)
218 afhi->tags.year = para_strdup(NULL);
219 if (!afhi->tags.album)
220 afhi->tags.album = para_strdup(NULL);
221 if (!afhi->tags.comment)
222 afhi->tags.comment = para_strdup(NULL);
223 PARA_DEBUG_LOG("techinfo: %s\n", afhi->techinfo);
224 PARA_DEBUG_LOG("artist: %s\n", afhi->tags.artist);
225 PARA_DEBUG_LOG("title: %s\n", afhi->tags.title);
226 PARA_DEBUG_LOG("year: %s\n", afhi->tags.year);
227 PARA_DEBUG_LOG("album: %s\n", afhi->tags.album);
228 PARA_DEBUG_LOG("comment: %s\n", afhi->tags.comment);
229 return ret;
230 }
231
232 /**
233 * Deallocate contents of a filled-in ahi structure
234 *
235 * \param afhi The structure to clear.
236 *
237 * The given pointer is kept, everything else is freed.
238 */
239 void clear_afhi(struct afh_info *afhi)
240 {
241 if (!afhi)
242 return;
243 free(afhi->chunk_table);
244 free(afhi->techinfo);
245 free(afhi->tags.artist);
246 free(afhi->tags.title);
247 free(afhi->tags.year);
248 free(afhi->tags.album);
249 free(afhi->tags.comment);
250 }
251
252 /**
253 * Get the name of the given audio format.
254 *
255 * \param i The audio format number.
256 *
257 * \return This returns a pointer to statically allocated memory so it
258 * must not be freed by the caller.
259 */
260 const char *audio_format_name(int i)
261 {
262 if (i < 0 || i >= ARRAY_SIZE(afl) - 1)
263 return "???";
264 return afl[i].name;
265 }
266
267 static inline size_t get_chunk_len(long unsigned chunk_num,
268 const struct afh_info *afhi)
269 {
270 return afhi->chunk_table[chunk_num + 1] - afhi->chunk_table[chunk_num];
271 }
272
273 /**
274 * Get one chunk of audio data.
275 *
276 * \param chunk_num The number of the chunk to get.
277 * \param afhi Describes the audio file.
278 * \param map The memory mapped audio file.
279 * \param buf Result pointer.
280 * \param len The length of the chunk in bytes.
281 *
282 * Upon return, \a buf will point so memory inside \a map. The returned buffer
283 * must therefore not be freed by the caller.
284 */
285 void afh_get_chunk(long unsigned chunk_num, struct afh_info *afhi,
286 void *map, const char **buf, size_t *len)
287 {
288 size_t pos = afhi->chunk_table[chunk_num];
289 *buf = map + pos;
290 *len = get_chunk_len(chunk_num, afhi);
291 }
292
293 /**
294 * Find a suitable start chunk.
295 *
296 * \param approx_chunk_num Upper bound for the chunk number to return.
297 * \param afhi Needed for the chunk table.
298 *
299 * \return The first non-empty chunk <= \a approx_chunk_num.
300 *
301 * \sa \ref afh_get_chunk().
302 */
303 int32_t afh_get_start_chunk(int32_t approx_chunk_num,
304 const struct afh_info *afhi)
305 {
306 int32_t k;
307
308 for (k = PARA_MAX(0, approx_chunk_num); k >= 0; k--)
309 if (get_chunk_len(k, afhi) > 0)
310 break;
311 return k;
312 }
313
314 /**
315 * Get the header of an audio file.
316 *
317 * \param afhi The audio file handler data describing the file.
318 * \param audio_format_id Determines the audio format handler.
319 * \param map The data of the audio file.
320 * \param mapsize The amount of bytes of the mmapped audio file.
321 * \param buf The length of the header is stored here.
322 * \param len Points to a buffer containing the header on return.
323 *
324 * This function sets \a buf to \p NULL and \a len to zero if \a map or \a
325 * afhi is \p NULL, or if the current audio format does not need special
326 * header treatment.
327 *
328 * Otherwise, it is checked whether the audio format handler given by
329 * \a audio_format_id defines a ->get_header() method. If it does, this
330 * method is called to obtain the header. If ->get_header() is \p NULL,
331 * a reference to the first chunk of the audio file is returned.
332 *
333 * Once the header is no longer needed, the caller must call \ref
334 * afh_free_header() to free the resources allocated by this function.
335 */
336 void afh_get_header(struct afh_info *afhi, uint8_t audio_format_id,
337 void *map, size_t mapsize, char **buf, size_t *len)
338 {
339 struct audio_format_handler *afh = afl + audio_format_id;
340
341 if (!map || !afhi || !afhi->header_len) {
342 *buf = NULL;
343 *len = 0;
344 return;
345 }
346 if (!afh->get_header) {
347 *len = afhi->header_len;
348 *buf = map;
349 return;
350 }
351 afh->get_header(map, mapsize, buf, len);
352 }
353
354 /**
355 * Deallocate any resources obtained from afh_get_header().
356 *
357 * \param header_buf Pointer obtained via afh_get_header().
358 * \param audio_format_id Determines the audio format handler.
359 */
360 void afh_free_header(char *header_buf, uint8_t audio_format_id)
361 {
362 struct audio_format_handler *afh = afl + audio_format_id;
363
364 if (afh->get_header)
365 free(header_buf);
366 }
367
368 /**
369 * Pretty-print the contents of a struct afh_info into a buffer.
370 *
371 * \param audio_format_num The audio format number.
372 * \param afhi Pointer to the structure that contains the information.
373 * \param result Pretty-printed ahfi is here after the call.
374 *
375 * The \a result buffer is dynamically allocated and should be freed by the
376 * caller.
377 *
378 * \return The number of bytes. This function never fails.
379 */
380 unsigned afh_get_afhi_txt(int audio_format_num, struct afh_info *afhi, char **result)
381 {
382 return xasprintf(result, "%s: %dkbit/s\n" /* bitrate */
383 "%s: %s\n" /* format */
384 "%s: %dHz\n" /* frequency */
385 "%s: %d\n" /* channels */
386 "%s: %lu\n" /* seconds total */
387 "%s: %lu: %lu\n" /* chunk time */
388 "%s: %lu\n" /* num chunks */
389 "%s: %s\n" /* techinfo */
390 "%s: %s\n" /* artist */
391 "%s: %s\n" /* title */
392 "%s: %s\n" /* year */
393 "%s: %s\n" /* album */
394 "%s: %s\n", /* comment */
395 status_item_list[SI_BITRATE], afhi->bitrate,
396 status_item_list[SI_FORMAT], audio_format_name(audio_format_num),
397 status_item_list[SI_FREQUENCY], afhi->frequency,
398 status_item_list[SI_CHANNELS], afhi->channels,
399 status_item_list[SI_SECONDS_TOTAL], afhi->seconds_total,
400 status_item_list[SI_CHUNK_TIME], (long unsigned)afhi->chunk_tv.tv_sec,
401 (long unsigned)afhi->chunk_tv.tv_usec,
402 status_item_list[SI_NUM_CHUNKS], afhi->chunks_total,
403 status_item_list[SI_TECHINFO], afhi->techinfo? afhi->techinfo : "",
404 status_item_list[SI_ARTIST], afhi->tags.artist? afhi->tags.artist : "",
405 status_item_list[SI_TITLE], afhi->tags.title? afhi->tags.title : "",
406 status_item_list[SI_YEAR], afhi->tags.year? afhi->tags.year : "",
407 status_item_list[SI_ALBUM], afhi->tags.album? afhi->tags.album : "",
408 status_item_list[SI_COMMENT], afhi->tags.comment? afhi->tags.comment : ""
409 );
410 }