afh_common.c

   1 /*
   2  * Copyright (C) 1997-2009 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/time.h> /* gettimeofday */
  11 #include <sys/types.h>
  12 #include <dirent.h>
  13
  14 #include "para.h"
  15 #include "error.h"
  16 #include "string.h"
  17 #include "afh.h"
  18
  19 /* The mp3 audio format handler does not need any libs. */
  20 void mp3_init(struct audio_format_handler *);
  21
  22 #ifdef HAVE_OGGVORBIS
  23         void ogg_init(struct audio_format_handler *);
  24 #endif
  25 #ifdef HAVE_FAAD
  26         void aac_afh_init(struct audio_format_handler *);
  27 #endif
  28
  29 /**
  30  * The list of supported audio formats.
  31  *
  32  * We always define the full array of audio formats even if some audio formats
  33  * were not compiled in. This is because for each audio file the number of its
  34  * audio format is stored in the database. We don't want that numbers to become
  35  * stale just because the user installed a new version of paraslash that
  36  * supports a different set of audio formats.
  37  *
  38  * It can still be easily detected whether an audio format is compiled in by
  39  * checking if the init function pointer is not \p NULL.
  40  */
  41 static struct audio_format_handler afl[] = {
  42         {
  43                 .name = "mp3",
  44                 .init = mp3_init,
  45         },
  46         {
  47                 .name = "ogg",
  48 #ifdef HAVE_OGGVORBIS
  49                 .init = ogg_init,
  50 #endif
  51         },
  52         {
  53                 .name = "aac",
  54 #ifdef HAVE_FAAD
  55                 .init = aac_afh_init,
  56 #endif
  57         },
  58         {
  59                 .name = NULL,
  60         }
  61 };
  62
  63 static inline int next_audio_format(int format)
  64 {
  65         for (;;) {
  66                 if (!afl[format].name)
  67                         return format;
  68                 format++;
  69                 if (afl[format].init)
  70                         return format;
  71         }
  72
  73 }
  74
  75 /** Iterate over each supported audio format. */
  76 #define FOR_EACH_AUDIO_FORMAT(i) for (i = 0; afl[i].name; i = next_audio_format(i))
  77
  78 /**
  79  * Call the init function of each supported audio format handler.
  80  */
  81 void afh_init(void)
  82 {
  83         int i;
  84
  85         PARA_INFO_LOG("supported audio formats: %s\n",
  86                 SUPPORTED_AUDIO_FORMATS);
  87         FOR_EACH_AUDIO_FORMAT(i) {
  88                 PARA_NOTICE_LOG("initializing %s handler\n",
  89                         audio_format_name(i));
  90                 afl[i].init(&afl[i]);
  91         }
  92 }
  93
  94 /**
  95  * Guess the audio format judging from filename.
  96  *
  97  * \param name The filename.
  98  *
  99  * \return This function returns \p -E_AUDIO_FORMAT if it has no idea what kind
 100  * of audio file this might be. Otherwise the (non-negative) number of the
 101  * audio format is returned.
 102  */
 103 int guess_audio_format(const char *name)
 104 {
 105         int i,j, len = strlen(name);
 106
 107         FOR_EACH_AUDIO_FORMAT(i) {
 108                 for (j = 0; afl[i].suffixes[j]; j++) {
 109                         const char *p = afl[i].suffixes[j];
 110                         int plen = strlen(p);
 111                         if (len < plen + 1)
 112                                 continue;
 113                         if (name[len - plen - 1] != '.')
 114                                 continue;
 115                         if (strcasecmp(name + len - plen, p))
 116                                 continue;
 117 //                      PARA_DEBUG_LOG("might be %s\n", audio_format_name(i));
 118                         return i;
 119                 }
 120         }
 121         return -E_AUDIO_FORMAT;
 122 }
 123
 124 /**
 125  * Pretty-print the given meta-info.
 126  *
 127  * \param title The title of the audio file.
 128  * \param artist The artist.
 129  * \param album The name of the album.
 130  * \param year Year of release.
 131  * \param comment Further comments.
 132  *
 133  * This function is called by each audio format handler to produce the tag info
 134  * status items. Usually, the audio format handlers read this info from the
 135  * audio file (id3 tags, vorbis comments, ...).
 136  *
 137  * It is OK to pass \p NULL pointers for any argument in which case a suitable
 138  * string is inserted which indicates that this information is not available.
 139  *
 140  * \return The status item string. It must be freed by the caller.
 141  */
 142 char *make_taginfo(char *title, char *artist, char *album, char *year,
 143                 char *comment)
 144 {
 145         return make_message("%s: %s, by %s\n" /* taginfo1 */
 146                 "%s: A: %s, Y: %s, C: %s\n", /* taginfo2 */
 147                 status_item_list[SI_TAGINFO1],
 148                 (title && *title)? title : "(title tag not set)",
 149                 (artist && *artist)? artist : "(artist tag not set)",
 150                 status_item_list[SI_TAGINFO2],
 151                 (album && *album)?  album : "(album tag not set)",
 152                 (year && *year)? year : "????",
 153                 (comment && *comment)? comment : "(comment tag not set)"
 154         );
 155 }
 156
 157 /**
 158  * Call get_file_info() to obtain an afhi structure.
 159  *
 160  * \param path The full path of the audio file.
 161  * \param data Pointer to the contents of the (mapped) file.
 162  * \param size The file size in bytes.
 163  * \param fd The open file descriptor.
 164  * \param afhi Result pointer.
 165  *
 166  * \return The number of the audio format on success, \p -E_AUDIO_FORMAT if no
 167  * compiled in audio format handler is able to handler the file.
 168  *
 169  * This function tries to find an audio format handler that can interpret the
 170  * file given by \a data and \a size.
 171  *
 172  * It first tries to determine the audio format from the filename given by \a
 173  * path. If this doesn't work, all other audio format handlers are tried until
 174  * one is found that can handle the file.
 175  */
 176 int compute_afhi(const char *path, char *data, size_t size, int fd,
 177                 struct afh_info *afhi)
 178 {
 179         int ret, i, format;
 180
 181         afhi->header_offset = 0;
 182         afhi->header_len = 0;
 183         format = guess_audio_format(path);
 184
 185         if (format >= 0) {
 186                 ret = afl[format].get_file_info(data, size, fd, afhi);
 187                 if (ret >= 0)
 188                         return format;
 189         }
 190         FOR_EACH_AUDIO_FORMAT(i) {
 191                 if (i == format) /* we already tried this one to no avail */
 192                         continue;
 193                 ret = afl[i].get_file_info(data, size, fd, afhi);
 194                 if (ret >= 0)
 195                         return i;
 196                 PARA_WARNING_LOG("%s\n", para_strerror(-ret));
 197         }
 198         return -E_AUDIO_FORMAT;
 199 }
 200
 201 /**
 202  * Get the name of the given audio format.
 203  *
 204  * \param i The audio format number.
 205  *
 206  * This returns a pointer to statically allocated memory so it
 207  * must not be freed by the caller.
 208  */
 209 const char *audio_format_name(int i)
 210 {
 211         //PARA_NOTICE_LOG("array size: %u¸ requested: %d\n", ARRAY_SIZE(afl), i);
 212         assert(i < 0 || i < ARRAY_SIZE(afl) - 1);
 213         return i >= 0?  afl[i].name : "(none)";
 214 }
 215
 216 /**
 217  * Get one chunk of audio data.
 218  *
 219  * \param chunk_num The number of the chunk to get.
 220  * \param afhi Describes the audio file.
 221  * \param map The memory mapped audio file.
 222  * \param buf Result pointer.
 223  * \param len The length of the chunk in bytes.
 224  *
 225  * Upon return, \a buf will point so memory inside \a map. The returned buffer
 226  * must therefore not be freed by the caller.
 227  */
 228 void afh_get_chunk(long unsigned chunk_num, struct afh_info *afhi,
 229                 void *map, const char **buf, size_t *len)
 230 {
 231         size_t pos = afhi->chunk_table[chunk_num];
 232         *buf = map + pos;
 233         *len = afhi->chunk_table[chunk_num + 1] - pos;
 234 }
 235
 236 uint32_t afh_get_largest_chunk_size(struct afh_info *afhi)
 237 {
 238         uint32_t n, largest = 0, *ct = afhi->chunk_table;
 239
 240         for (n = 1; n <= afhi->chunks_total; n++)
 241                 largest = PARA_MAX(largest, ct[n] - ct[n - 1]);
 242         return largest;
 243 }
 244
 245 /**
 246  * Get the header of an audio file.
 247  *
 248  * \param afhi The audio file handler data describing the file.
 249  * \param map The data of the audio file.
 250  * \param buf The length of the header is stored here.
 251  * \param len Points to a buffer containing the header on return.
 252  *
 253  * This function sets \a buf to \p NULL and \a len to zero if \a map or \a
 254  * afhi is \p NULL, or if the current audio format does not need special
 255  * header treamtment.
 256  */
 257 void afh_get_header(struct afh_info *afhi, void *map, const char **buf, size_t *len)
 258 {
 259         if (!map || !afhi || ! afhi->header_len) {
 260                 *buf = NULL;
 261                 *len = 0;
 262         }
 263         *len = afhi->header_len;
 264         *buf = map + afhi->header_offset;
 265 }