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 /* It does not hurt to declare init functions which are not available. */
  20 extern afh_init_func mp3_init, ogg_init, aac_afh_init, wma_afh_init,
  21         spx_afh_init, flac_afh_init, opus_afh_init;
  22
  23 /** The list of all status items */
  24 const char *status_item_list[] = {STATUS_ITEM_ARRAY};
  25
  26 /**
  27  * The list of supported audio formats.
  28  *
  29  * We always define the full array of audio formats even if some audio formats
  30  * were not compiled in. This is because for each audio file the number of its
  31  * audio format is stored in the database. We don't want that numbers to become
  32  * stale just because the user installed a new version of paraslash that
  33  * supports a different set of audio formats.
  34  *
  35  * It can still be easily detected whether an audio format is compiled in by
  36  * checking if the init function pointer is not \p NULL.
  37  */
  38 static struct audio_format_handler afl[] = {
  39         {
  40                 .name = "mp3",
  41                 .init = mp3_init,
  42         },
  43         {
  44                 .name = "ogg",
  45 #if defined(HAVE_OGG) && defined(HAVE_VORBIS)
  46                 .init = ogg_init,
  47 #endif
  48         },
  49         {
  50                 .name = "aac",
  51 #ifdef HAVE_FAAD
  52                 .init = aac_afh_init,
  53 #endif
  54         },
  55         {
  56                 .name = "wma",
  57                 .init = wma_afh_init,
  58         },
  59         {
  60                 .name = "spx",
  61 #if defined(HAVE_OGG) && defined(HAVE_SPEEX)
  62                 .init = spx_afh_init,
  63 #endif
  64         },
  65         {
  66                 .name = "flac",
  67 #ifdef HAVE_FLAC
  68                 .init = flac_afh_init,
  69 #endif
  70         },
  71         {
  72                 .name = "opus",
  73 #if defined(HAVE_OGG) && defined(HAVE_OPUS)
  74                 .init = opus_afh_init,
  75 #endif
  76         },
  77         {
  78                 .name = NULL,
  79         }
  80 };
  81
  82 static inline int next_audio_format(int format)
  83 {
  84         for (;;) {
  85                 if (!afl[format].name)
  86                         return format;
  87                 format++;
  88                 if (afl[format].init)
  89                         return format;
  90         }
  91
  92 }
  93
  94 /** Iterate over each supported audio format. */
  95 #define FOR_EACH_AUDIO_FORMAT(i) for (i = 0; afl[i].name; i = next_audio_format(i))
  96
  97 /**
  98  * Call the init function of each supported audio format handler.
  99  */
 100 void afh_init(void)
 101 {
 102         int i;
 103
 104         PARA_NOTICE_LOG("supported audio formats: %s\n", AUDIO_FORMAT_HANDLERS);
 105         FOR_EACH_AUDIO_FORMAT(i) {
 106                 PARA_INFO_LOG("initializing %s handler\n",
 107                         audio_format_name(i));
 108                 afl[i].init(&afl[i]);
 109         }
 110 }
 111
 112 /**
 113  * Guess the audio format judging from filename.
 114  *
 115  * \param name The filename.
 116  *
 117  * \return This function returns \p -E_AUDIO_FORMAT if it has no idea what kind
 118  * of audio file this might be. Otherwise the (non-negative) number of the
 119  * audio format is returned.
 120  */
 121 int guess_audio_format(const char *name)
 122 {
 123         int i,j, len = strlen(name);
 124
 125         FOR_EACH_AUDIO_FORMAT(i) {
 126                 for (j = 0; afl[i].suffixes[j]; j++) {
 127                         const char *p = afl[i].suffixes[j];
 128                         int plen = strlen(p);
 129                         if (len < plen + 1)
 130                                 continue;
 131                         if (name[len - plen - 1] != '.')
 132                                 continue;
 133                         if (strcasecmp(name + len - plen, p))
 134                                 continue;
 135 //                      PARA_DEBUG_LOG("might be %s\n", audio_format_name(i));
 136                         return i;
 137                 }
 138         }
 139         return -E_AUDIO_FORMAT;
 140 }
 141
 142 /**
 143  * Call get_file_info() to obtain an afhi structure.
 144  *
 145  * \param path The full path of the audio file.
 146  * \param data Pointer to the contents of the (mapped) file.
 147  * \param size The file size in bytes.
 148  * \param fd The open file descriptor.
 149  * \param afhi Result pointer.
 150  *
 151  * \return The number of the audio format on success, \p -E_AUDIO_FORMAT if no
 152  * compiled in audio format handler is able to handler the file.
 153  *
 154  * This function tries to find an audio format handler that can interpret the
 155  * file given by \a data and \a size.
 156  *
 157  * It first tries to determine the audio format from the filename given by \a
 158  * path. If this doesn't work, all other audio format handlers are tried until
 159  * one is found that can handle the file.
 160  */
 161 int compute_afhi(const char *path, char *data, size_t size, int fd,
 162                 struct afh_info *afhi)
 163 {
 164         int ret, i, format;
 165
 166         afhi->header_len = 0;
 167         afhi->techinfo = NULL;
 168         afhi->tags.artist = NULL;
 169         afhi->tags.title = NULL;
 170         afhi->tags.year = NULL;
 171         afhi->tags.album = NULL;
 172         afhi->tags.comment = NULL;
 173         format = guess_audio_format(path);
 174
 175         if (format >= 0) {
 176                 ret = afl[format].get_file_info(data, size, fd, afhi);
 177                 if (ret >= 0) {
 178                         ret = format;
 179                         goto success;
 180                 }
 181         }
 182         FOR_EACH_AUDIO_FORMAT(i) {
 183                 if (i == format) /* we already tried this one to no avail */
 184                         continue;
 185                 ret = afl[i].get_file_info(data, size, fd, afhi);
 186                 if (ret >= 0) {
 187                         ret = i;
 188                         goto success;
 189                 }
 190                 PARA_WARNING_LOG("%s\n", para_strerror(-ret));
 191         }
 192         return -E_AUDIO_FORMAT;
 193 success:
 194         if (!afhi->techinfo)
 195                 afhi->techinfo = para_strdup(NULL);
 196         if (!afhi->tags.artist)
 197                 afhi->tags.artist = para_strdup(NULL);
 198         if (!afhi->tags.title)
 199                 afhi->tags.title = para_strdup(NULL);
 200         if (!afhi->tags.year)
 201                 afhi->tags.year = para_strdup(NULL);
 202         if (!afhi->tags.album)
 203                 afhi->tags.album = para_strdup(NULL);
 204         if (!afhi->tags.comment)
 205                 afhi->tags.comment = para_strdup(NULL);
 206         PARA_DEBUG_LOG("techinfo: %s\n", afhi->techinfo);
 207         PARA_DEBUG_LOG("artist: %s\n", afhi->tags.artist);
 208         PARA_DEBUG_LOG("title: %s\n", afhi->tags.title);
 209         PARA_DEBUG_LOG("year: %s\n", afhi->tags.year);
 210         PARA_DEBUG_LOG("album: %s\n", afhi->tags.album);
 211         PARA_DEBUG_LOG("comment: %s\n", afhi->tags.comment);
 212         return ret;
 213 }
 214
 215 /**
 216  * Deallocate the contents of an afh_info structure.
 217  *
 218  * \param afhi The structure to clear.
 219  *
 220  * This only frees the memory the various pointer fields of \a afhi point to.
 221  * It does *not* free \a afhi itself.
 222  */
 223 void clear_afhi(struct afh_info *afhi)
 224 {
 225         if (!afhi)
 226                 return;
 227         free(afhi->chunk_table);
 228         free(afhi->techinfo);
 229         free(afhi->tags.artist);
 230         free(afhi->tags.title);
 231         free(afhi->tags.year);
 232         free(afhi->tags.album);
 233         free(afhi->tags.comment);
 234 }
 235
 236 /**
 237  * Get the name of the given audio format.
 238  *
 239  * \param i The audio format number.
 240  *
 241  * \return This returns a pointer to statically allocated memory so it
 242  * must not be freed by the caller.
 243  */
 244 const char *audio_format_name(int i)
 245 {
 246         if (i < 0 || i >= ARRAY_SIZE(afl) - 1)
 247                 return "???";
 248         return afl[i].name;
 249 }
 250
 251 static inline size_t get_chunk_len(long unsigned chunk_num,
 252                 const struct afh_info *afhi)
 253 {
 254         return afhi->chunk_table[chunk_num + 1] - afhi->chunk_table[chunk_num];
 255 }
 256
 257 /**
 258  * Get one chunk of audio data.
 259  *
 260  * \param chunk_num The number of the chunk to get.
 261  * \param afhi Describes the audio file.
 262  * \param map The memory mapped audio file.
 263  * \param buf Result pointer.
 264  * \param len The length of the chunk in bytes.
 265  *
 266  * Upon return, \a buf will point so memory inside \a map. The returned buffer
 267  * must therefore not be freed by the caller.
 268  */
 269 void afh_get_chunk(long unsigned chunk_num, struct afh_info *afhi,
 270                 void *map, const char **buf, size_t *len)
 271 {
 272         size_t pos = afhi->chunk_table[chunk_num];
 273         *buf = map + pos;
 274         *len = get_chunk_len(chunk_num, afhi);
 275 }
 276
 277 /**
 278  * Find a suitable start chunk.
 279  *
 280  * \param approx_chunk_num Upper bound for the chunk number to return.
 281  * \param afhi Needed for the chunk table.
 282  *
 283  * \return The first non-empty chunk <= \a approx_chunk_num.
 284  *
 285  * \sa \ref afh_get_chunk().
 286  */
 287 int32_t afh_get_start_chunk(int32_t approx_chunk_num,
 288                 const struct afh_info *afhi)
 289 {
 290         int32_t k;
 291
 292         for (k = PARA_MAX(0, approx_chunk_num); k >= 0; k--)
 293                 if (get_chunk_len(k, afhi) > 0)
 294                         break;
 295         return k;
 296 }
 297
 298 /**
 299  * Get the header of an audio file.
 300  *
 301  * \param afhi The audio file handler data describing the file.
 302  * \param audio_format_id Determines the audio format handler.
 303  * \param map The data of the audio file.
 304  * \param mapsize The amount of bytes of the mmapped audio file.
 305  * \param buf The length of the header is stored here.
 306  * \param len Points to a buffer containing the header on return.
 307  *
 308  * This function sets \a buf to \p NULL and \a len to zero if \a map or \a
 309  * afhi is \p NULL, or if the current audio format does not need special
 310  * header treatment.
 311  *
 312  * Otherwise, it is checked whether the audio format handler given by
 313  * \a audio_format_id defines a ->get_header() method. If it does, this
 314  * method is called to obtain the header. If ->get_header() is \p NULL,
 315  * a reference to the first chunk of the audio file is returned.
 316  *
 317  * Once the header is no longer needed, the caller must call \ref
 318  * afh_free_header() to free the resources allocated by this function.
 319  */
 320 void afh_get_header(struct afh_info *afhi, uint8_t audio_format_id,
 321                 void *map, size_t mapsize, char **buf, size_t *len)
 322 {
 323         struct audio_format_handler *afh = afl + audio_format_id;
 324
 325         if (!map || !afhi || !afhi->header_len) {
 326                 *buf = NULL;
 327                 *len = 0;
 328                 return;
 329         }
 330         if (!afh->get_header) {
 331                 *len = afhi->header_len;
 332                 *buf = map;
 333                 return;
 334         }
 335         afh->get_header(map, mapsize, buf, len);
 336 }
 337
 338 /**
 339  * Deallocate any resources obtained from afh_get_header().
 340  *
 341  * \param header_buf Pointer obtained via afh_get_header().
 342  * \param audio_format_id Determines the audio format handler.
 343  */
 344 void afh_free_header(char *header_buf, uint8_t audio_format_id)
 345 {
 346         struct audio_format_handler *afh = afl + audio_format_id;
 347
 348         if (afh->get_header)
 349                 free(header_buf);
 350 }
 351
 352 /**
 353  * Pretty-print the contents of a struct afh_info into a buffer.
 354  *
 355  * \param audio_format_num The audio format number.
 356  * \param afhi Pointer to the structure that contains the information.
 357  * \param result Pretty-printed ahfi is here after the call.
 358  *
 359  * The \a result buffer is dynamically allocated and should be freed by the
 360  * caller.
 361  *
 362  * \return The number of bytes. This function never fails.
 363  */
 364 unsigned afh_get_afhi_txt(int audio_format_num, struct afh_info *afhi, char **result)
 365 {
 366         return xasprintf(result, "%s: %dkbit/s\n" /* bitrate */
 367                 "%s: %s\n" /* format */
 368                 "%s: %dHz\n" /* frequency */
 369                 "%s: %d\n" /* channels */
 370                 "%s: %lu\n" /* seconds total */
 371                 "%s: %lu: %lu\n" /* chunk time */
 372                 "%s: %lu\n" /* num chunks */
 373                 "%s: %s\n" /* techinfo */
 374                 "%s: %s\n" /* artist */
 375                 "%s: %s\n" /* title */
 376                 "%s: %s\n" /* year */
 377                 "%s: %s\n" /* album */
 378                 "%s: %s\n", /* comment */
 379                 status_item_list[SI_BITRATE], afhi->bitrate,
 380                 status_item_list[SI_FORMAT], audio_format_name(audio_format_num),
 381                 status_item_list[SI_FREQUENCY], afhi->frequency,
 382                 status_item_list[SI_CHANNELS], afhi->channels,
 383                 status_item_list[SI_SECONDS_TOTAL], afhi->seconds_total,
 384                 status_item_list[SI_CHUNK_TIME], (long unsigned)afhi->chunk_tv.tv_sec,
 385                         (long unsigned)afhi->chunk_tv.tv_usec,
 386                 status_item_list[SI_NUM_CHUNKS], afhi->chunks_total,
 387                 status_item_list[SI_TECHINFO], afhi->techinfo? afhi->techinfo : "",
 388                 status_item_list[SI_ARTIST], afhi->tags.artist? afhi->tags.artist : "",
 389                 status_item_list[SI_TITLE], afhi->tags.title? afhi->tags.title : "",
 390                 status_item_list[SI_YEAR], afhi->tags.year? afhi->tags.year : "",
 391                 status_item_list[SI_ALBUM], afhi->tags.album? afhi->tags.album : "",
 392                 status_item_list[SI_COMMENT], afhi->tags.comment? afhi->tags.comment : ""
 393         );
 394 }
 395
 396 /**
 397  * Create a copy of the given file with altered meta tags.
 398  *
 399  * \param audio_format_id Specifies the audio format.
 400  * \param map The (read-only) memory map of the input file.
 401  * \param mapsize The size of the input file in bytes.
 402  * \param tags The new tags.
 403  * \param output_fd Altered file is created using this file descriptor.
 404  * \param filename The name of the temporary output file.
 405  *
 406  * This calls the ->rewrite_tags method of the audio format handler associated
 407  * with \a audio_format_id to create a copy of the memory-mapped file given
 408  * by \a map and \a mapsize, but with altered tags according to \a tags. If
 409  * the audio format handler for \a audio_format_id lacks this optional method,
 410  * the function returns (the paraslash error code of) \p ENOTSUP.
 411  *
 412  * \return Standard.
 413  */
 414 int afh_rewrite_tags(int audio_format_id, void *map, size_t mapsize,
 415                 struct taginfo *tags, int output_fd, const char *filename)
 416 {
 417         struct audio_format_handler *afh = afl + audio_format_id;
 418
 419         if (!afh->rewrite_tags)
 420                 return -ERRNO_TO_PARA_ERROR(ENOTSUP);
 421         return afh->rewrite_tags(map, mapsize, tags, output_fd, filename);
 422 }