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 #include <regex.h>
  14
  15 #include "para.h"
  16 #include "error.h"
  17 #include "string.h"
  18 #include "afh.h"
  19
  20 /* The mp3 audio format handler does not need any libs. */
  21 void mp3_init(struct audio_format_handler *);
  22
  23 #ifdef HAVE_OGGVORBIS
  24         void ogg_init(struct audio_format_handler *);
  25 #endif
  26 #ifdef HAVE_FAAD
  27         void aac_afh_init(struct audio_format_handler *);
  28 #endif
  29
  30 /**
  31  * The list of supported audio formats.
  32  *
  33  * We always define the full array of audio formats even if some audio formats
  34  * were not compiled in. This is because for each audio file the number of its
  35  * audio format is stored in the database. We don't want that numbers to become
  36  * stale just because the user installed a new version of paraslash that
  37  * supports a different set of audio formats.
  38  *
  39  * It can still be easily detected whether an audio format is compiled in by
  40  * checking if the init function pointer is not \p NULL.
  41  */
  42 static struct audio_format_handler afl[] = {
  43         {
  44                 .name = "mp3",
  45                 .init = mp3_init,
  46         },
  47         {
  48                 .name = "ogg",
  49 #ifdef HAVE_OGGVORBIS
  50                 .init = ogg_init,
  51 #endif
  52         },
  53         {
  54                 .name = "aac",
  55 #ifdef HAVE_FAAD
  56                 .init = aac_afh_init,
  57 #endif
  58         },
  59         {
  60                 .name = NULL,
  61         }
  62 };
  63
  64 static inline int next_audio_format(int format)
  65 {
  66         for (;;) {
  67                 if (!afl[format].name)
  68                         return format;
  69                 format++;
  70                 if (afl[format].init)
  71                         return format;
  72         }
  73
  74 }
  75
  76 /** Iterate over each supported audio format. */
  77 #define FOR_EACH_AUDIO_FORMAT(i) for (i = 0; afl[i].name; i = next_audio_format(i))
  78
  79 /**
  80  * Call the init function of each supported audio format handler.
  81  */
  82 void afh_init(void)
  83 {
  84         int i;
  85
  86         PARA_INFO_LOG("supported audio formats: %s\n",
  87                 SUPPORTED_AUDIO_FORMATS);
  88         FOR_EACH_AUDIO_FORMAT(i) {
  89                 PARA_NOTICE_LOG("initializing %s handler\n",
  90                         audio_format_name(i));
  91                 afl[i].init(&afl[i]);
  92         }
  93 }
  94
  95 /**
  96  * Guess the audio format judging from filename.
  97  *
  98  * \param name The filename.
  99  *
 100  * \return This function returns \p -E_AUDIO_FORMAT if it has no idea what kind
 101  * of audio file this might be. Otherwise the (non-negative) number of the
 102  * audio format is returned.
 103  */
 104 int guess_audio_format(const char *name)
 105 {
 106         int i,j, len = strlen(name);
 107
 108         FOR_EACH_AUDIO_FORMAT(i) {
 109                 for (j = 0; afl[i].suffixes[j]; j++) {
 110                         const char *p = afl[i].suffixes[j];
 111                         int plen = strlen(p);
 112                         if (len < plen + 1)
 113                                 continue;
 114                         if (name[len - plen - 1] != '.')
 115                                 continue;
 116                         if (strcasecmp(name + len - plen, p))
 117                                 continue;
 118 //                      PARA_DEBUG_LOG("might be %s\n", audio_format_name(i));
 119                         return i;
 120                 }
 121         }
 122         return -E_AUDIO_FORMAT;
 123 }
 124
 125 /**
 126  * Call get_file_info() to obtain an afhi structure.
 127  *
 128  * \param path The full path of the audio file.
 129  * \param data Pointer to the contents of the (mapped) file.
 130  * \param size The file size in bytes.
 131  * \param fd The open file descriptor.
 132  * \param afhi Result pointer.
 133  *
 134  * \return The number of the audio format on success, \p -E_AUDIO_FORMAT if no
 135  * compiled in audio format handler is able to handler the file.
 136  *
 137  * This function tries to find an audio format handler that can interpret the
 138  * file given by \a data and \a size.
 139  *
 140  * It first tries to determine the audio format from the filename given by \a
 141  * path. If this doesn't work, all other audio format handlers are tried until
 142  * one is found that can handle the file.
 143  */
 144 int compute_afhi(const char *path, char *data, size_t size, int fd,
 145                 struct afh_info *afhi)
 146 {
 147         int ret, i, format;
 148
 149         afhi->header_offset = 0;
 150         afhi->header_len = 0;
 151         afhi->techinfo = NULL;
 152         afhi->tags.artist = NULL;
 153         afhi->tags.title = NULL;
 154         afhi->tags.year = NULL;
 155         afhi->tags.album = NULL;
 156         afhi->tags.comment = NULL;
 157         format = guess_audio_format(path);
 158
 159         if (format >= 0) {
 160                 ret = afl[format].get_file_info(data, size, fd, afhi);
 161                 if (ret >= 0) {
 162                         ret = format;
 163                         goto success;
 164                 }
 165         }
 166         FOR_EACH_AUDIO_FORMAT(i) {
 167                 if (i == format) /* we already tried this one to no avail */
 168                         continue;
 169                 ret = afl[i].get_file_info(data, size, fd, afhi);
 170                 if (ret >= 0) {
 171                         ret = i;
 172                         goto success;
 173                 }
 174                 PARA_WARNING_LOG("%s\n", para_strerror(-ret));
 175         }
 176         return -E_AUDIO_FORMAT;
 177 success:
 178         if (!afhi->techinfo)
 179                 afhi->techinfo = para_strdup(NULL);
 180         if (!afhi->tags.artist)
 181                 afhi->tags.artist = para_strdup(NULL);
 182         if (!afhi->tags.title)
 183                 afhi->tags.title = para_strdup(NULL);
 184         if (!afhi->tags.year)
 185                 afhi->tags.year = para_strdup(NULL);
 186         if (!afhi->tags.album)
 187                 afhi->tags.album = para_strdup(NULL);
 188         if (!afhi->tags.comment)
 189                 afhi->tags.comment = para_strdup(NULL);
 190         PARA_DEBUG_LOG("techinfo: %s\n", afhi->techinfo);
 191         PARA_DEBUG_LOG("artist: %s\n", afhi->tags.artist);
 192         PARA_DEBUG_LOG("title: %s\n", afhi->tags.title);
 193         PARA_DEBUG_LOG("year: %s\n", afhi->tags.year);
 194         PARA_DEBUG_LOG("album: %s\n", afhi->tags.album);
 195         PARA_DEBUG_LOG("comment: %s\n", afhi->tags.comment);
 196         return ret;
 197 }
 198
 199 /**
 200  * Get the name of the given audio format.
 201  *
 202  * \param i The audio format number.
 203  *
 204  * This returns a pointer to statically allocated memory so it
 205  * must not be freed by the caller.
 206  */
 207 const char *audio_format_name(int i)
 208 {
 209         if (i < 0 || i >= ARRAY_SIZE(afl) - 1)
 210                 return "???";
 211         return afl[i].name;
 212 }
 213
 214 /**
 215  * Get one chunk of audio data.
 216  *
 217  * \param chunk_num The number of the chunk to get.
 218  * \param afhi Describes the audio file.
 219  * \param map The memory mapped audio file.
 220  * \param buf Result pointer.
 221  * \param len The length of the chunk in bytes.
 222  *
 223  * Upon return, \a buf will point so memory inside \a map. The returned buffer
 224  * must therefore not be freed by the caller.
 225  */
 226 void afh_get_chunk(long unsigned chunk_num, struct afh_info *afhi,
 227                 void *map, const char **buf, size_t *len)
 228 {
 229         size_t pos = afhi->chunk_table[chunk_num];
 230         *buf = map + pos;
 231         *len = afhi->chunk_table[chunk_num + 1] - pos;
 232 }
 233
 234 uint32_t afh_get_largest_chunk_size(struct afh_info *afhi)
 235 {
 236         uint32_t n, largest = 0, *ct = afhi->chunk_table;
 237
 238         for (n = 1; n <= afhi->chunks_total; n++)
 239                 largest = PARA_MAX(largest, ct[n] - ct[n - 1]);
 240         return largest;
 241 }
 242
 243 /**
 244  * Get the header of an audio file.
 245  *
 246  * \param afhi The audio file handler data describing the file.
 247  * \param map The data of the audio file.
 248  * \param buf The length of the header is stored here.
 249  * \param len Points to a buffer containing the header on return.
 250  *
 251  * This function sets \a buf to \p NULL and \a len to zero if \a map or \a
 252  * afhi is \p NULL, or if the current audio format does not need special
 253  * header treatment.
 254  */
 255 void afh_get_header(struct afh_info *afhi, void *map, const char **buf, size_t *len)
 256 {
 257         if (!map || !afhi || !afhi->header_len) {
 258                 *buf = NULL;
 259                 *len = 0;
 260                 return;
 261         }
 262         *len = afhi->header_len;
 263         *buf = map + afhi->header_offset;
 264 }