src/decoder/mpg123_decoder_plugin.c

   1 /*
   2  * Copyright (C) 2003-2010 The Music Player Daemon Project
   3  * http://www.musicpd.org
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #include "config.h" /* must be first for large file support */
  21 #include "decoder_api.h"
  22 #include "audio_check.h"
  23
  24 #include <glib.h>
  25
  26 #include <mpg123.h>
  27
  28 #undef G_LOG_DOMAIN
  29 #define G_LOG_DOMAIN "mpg123"
  30
  31 static bool
  32 mpd_mpg123_init(G_GNUC_UNUSED const struct config_param *param)
  33 {
  34         mpg123_init();
  35
  36         return true;
  37 }
  38
  39 static void
  40 mpd_mpg123_finish(void)
  41 {
  42         mpg123_exit();
  43 }
  44
  45 /**
  46  * Opens a file with an existing #mpg123_handle.
  47  *
  48  * @param handle a handle which was created before; on error, this
  49  * function will not free it
  50  * @param audio_format this parameter is filled after successful
  51  * return
  52  * @return true on success
  53  */
  54 static bool
  55 mpd_mpg123_open(mpg123_handle *handle, const char *path_fs,
  56                 struct audio_format *audio_format)
  57 {
  58         GError *gerror = NULL;
  59         char *path_dup;
  60         int error;
  61         int channels, encoding;
  62         long rate;
  63
  64         /* mpg123_open() wants a writable string :-( */
  65         path_dup = g_strdup(path_fs);
  66
  67         error = mpg123_open(handle, path_dup);
  68         g_free(path_dup);
  69         if (error != MPG123_OK) {
  70                 g_warning("libmpg123 failed to open %s: %s",
  71                           path_fs, mpg123_plain_strerror(error));
  72                 return false;
  73         }
  74
  75         /* obtain the audio format */
  76
  77         error = mpg123_getformat(handle, &rate, &channels, &encoding);
  78         if (error != MPG123_OK) {
  79                 g_warning("mpg123_getformat() failed: %s",
  80                           mpg123_plain_strerror(error));
  81                 return false;
  82         }
  83
  84         if (encoding != MPG123_ENC_SIGNED_16) {
  85                 /* other formats not yet implemented */
  86                 g_warning("expected MPG123_ENC_SIGNED_16, got %d", encoding);
  87                 return false;
  88         }
  89
  90         if (!audio_format_init_checked(audio_format, rate, SAMPLE_FORMAT_S16,
  91                                        channels, &gerror)) {
  92                 g_warning("%s", gerror->message);
  93                 g_error_free(gerror);
  94                 return false;
  95         }
  96
  97         return true;
  98 }
  99
 100 static void
 101 mpd_mpg123_file_decode(struct decoder *decoder, const char *path_fs)
 102 {
 103         struct audio_format audio_format;
 104         mpg123_handle *handle;
 105         int error;
 106         off_t num_samples;
 107         enum decoder_command cmd;
 108
 109         /* open the file */
 110
 111         handle = mpg123_new(NULL, &error);
 112         if (handle == NULL) {
 113                 g_warning("mpg123_new() failed: %s",
 114                           mpg123_plain_strerror(error));
 115                 return;
 116         }
 117
 118         if (!mpd_mpg123_open(handle, path_fs, &audio_format)) {
 119                 mpg123_delete(handle);
 120                 return;
 121         }
 122
 123         num_samples = mpg123_length(handle);
 124
 125         /* tell MPD core we're ready */
 126
 127         decoder_initialized(decoder, &audio_format, false,
 128                             (float)num_samples /
 129                             (float)audio_format.sample_rate);
 130
 131         /* the decoder main loop */
 132
 133         do {
 134                 unsigned char buffer[8192];
 135                 size_t nbytes;
 136
 137                 /* decode */
 138
 139                 error = mpg123_read(handle, buffer, sizeof(buffer), &nbytes);
 140                 if (error != MPG123_OK) {
 141                         if (error != MPG123_DONE)
 142                                 g_warning("mpg123_read() failed: %s",
 143                                           mpg123_plain_strerror(error));
 144                         break;
 145                 }
 146
 147                 /* send to MPD */
 148
 149                 cmd = decoder_data(decoder, NULL, buffer, nbytes,
 150                                    0, NULL);
 151
 152                 /* seeking not yet implemented */
 153         } while (cmd == DECODE_COMMAND_NONE);
 154
 155         /* cleanup */
 156
 157         mpg123_delete(handle);
 158 }
 159
 160 static struct tag *
 161 mpd_mpg123_tag_dup(const char *path_fs)
 162 {
 163         struct audio_format audio_format;
 164         mpg123_handle *handle;
 165         int error;
 166         off_t num_samples;
 167         struct tag *tag;
 168
 169         handle = mpg123_new(NULL, &error);
 170         if (handle == NULL) {
 171                 g_warning("mpg123_new() failed: %s",
 172                           mpg123_plain_strerror(error));
 173                 return NULL;
 174         }
 175
 176         if (!mpd_mpg123_open(handle, path_fs, &audio_format)) {
 177                 mpg123_delete(handle);
 178                 return NULL;
 179         }
 180
 181         num_samples = mpg123_length(handle);
 182         if (num_samples <= 0) {
 183                 mpg123_delete(handle);
 184                 return NULL;
 185         }
 186
 187         tag = tag_new();
 188
 189         tag->time = num_samples / audio_format.sample_rate;
 190
 191         /* ID3 tag support not yet implemented */
 192
 193         mpg123_delete(handle);
 194         return tag;
 195 }
 196
 197 static const char *const mpg123_suffixes[] = {
 198         "mp3",
 199         NULL
 200 };
 201
 202 const struct decoder_plugin mpg123_decoder_plugin = {
 203         .name = "mpg123",
 204         .init = mpd_mpg123_init,
 205         .finish = mpd_mpg123_finish,
 206         .file_decode = mpd_mpg123_file_decode,
 207         /* streaming not yet implemented */
 208         .tag_dup = mpd_mpg123_tag_dup,
 209         .suffixes = mpg123_suffixes,
 210 };