src/output_internal.h

   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 #ifndef MPD_OUTPUT_INTERNAL_H
  21 #define MPD_OUTPUT_INTERNAL_H
  22
  23 #include "audio_format.h"
  24
  25 #include <glib.h>
  26
  27 #include <time.h>
  28
  29 enum audio_output_command {
  30         AO_COMMAND_NONE = 0,
  31         AO_COMMAND_ENABLE,
  32         AO_COMMAND_DISABLE,
  33         AO_COMMAND_OPEN,
  34
  35         /**
  36          * This command is invoked when the input audio format
  37          * changes.
  38          */
  39         AO_COMMAND_REOPEN,
  40
  41         AO_COMMAND_CLOSE,
  42         AO_COMMAND_PAUSE,
  43
  44         /**
  45          * Drains the internal (hardware) buffers of the device.  This
  46          * operation may take a while to complete.
  47          */
  48         AO_COMMAND_DRAIN,
  49
  50         AO_COMMAND_CANCEL,
  51         AO_COMMAND_KILL
  52 };
  53
  54 struct audio_output {
  55         /**
  56          * The device's configured display name.
  57          */
  58         const char *name;
  59
  60         /**
  61          * The plugin which implements this output device.
  62          */
  63         const struct audio_output_plugin *plugin;
  64
  65         /**
  66          * The plugin's internal data.  It is passed to every plugin
  67          * method.
  68          */
  69         void *data;
  70
  71         /**
  72          * The #mixer object associated with this audio output device.
  73          * May be NULL if none is available, or if software volume is
  74          * configured.
  75          */
  76         struct mixer *mixer;
  77
  78         /**
  79          * Shall this output always play something (i.e. silence),
  80          * even when playback is stopped?
  81          */
  82         bool always_on;
  83
  84         /**
  85          * Has the user enabled this device?
  86          */
  87         bool enabled;
  88
  89         /**
  90          * Is this device actually enabled, i.e. the "enable" method
  91          * has succeeded?
  92          */
  93         bool really_enabled;
  94
  95         /**
  96          * Is the device (already) open and functional?
  97          *
  98          * This attribute may only be modified by the output thread.
  99          * It is protected with #mutex: write accesses inside the
 100          * output thread and read accesses outside of it may only be
 101          * performed while the lock is held.
 102          */
 103         bool open;
 104
 105         /**
 106          * Is the device paused?  i.e. the output thread is in the
 107          * ao_pause() loop.
 108          */
 109         bool pause;
 110
 111         /**
 112          * If not NULL, the device has failed, and this timer is used
 113          * to estimate how long it should stay disabled (unless
 114          * explicitly reopened with "play").
 115          */
 116         GTimer *fail_timer;
 117
 118         /**
 119          * The configured audio format.
 120          */
 121         struct audio_format config_audio_format;
 122
 123         /**
 124          * The audio_format in which audio data is received from the
 125          * player thread (which in turn receives it from the decoder).
 126          */
 127         struct audio_format in_audio_format;
 128
 129         /**
 130          * The audio_format which is really sent to the device.  This
 131          * is basically config_audio_format (if configured) or
 132          * in_audio_format, but may have been modified by
 133          * plugin->open().
 134          */
 135         struct audio_format out_audio_format;
 136
 137         /**
 138          * The filter object of this audio output.  This is an
 139          * instance of chain_filter_plugin.
 140          */
 141         struct filter *filter;
 142
 143         /**
 144          * The replay_gain_filter_plugin instance of this audio
 145          * output.
 146          */
 147         struct filter *replay_gain_filter;
 148
 149         /**
 150          * The serial number of the last replay gain info.  0 means no
 151          * replay gain info was available.
 152          */
 153         unsigned replay_gain_serial;
 154
 155         /**
 156          * The convert_filter_plugin instance of this audio output.
 157          * It is the last item in the filter chain, and is responsible
 158          * for converting the input data into the appropriate format
 159          * for this audio output.
 160          */
 161         struct filter *convert_filter;
 162
 163         /**
 164          * The thread handle, or NULL if the output thread isn't
 165          * running.
 166          */
 167         GThread *thread;
 168
 169         /**
 170          * The next command to be performed by the output thread.
 171          */
 172         enum audio_output_command command;
 173
 174         /**
 175          * The music pipe which provides music chunks to be played.
 176          */
 177         const struct music_pipe *pipe;
 178
 179         /**
 180          * This mutex protects #open, #chunk and #chunk_finished.
 181          */
 182         GMutex *mutex;
 183
 184         /**
 185          * This condition object wakes up the output thread after
 186          * #command has been set.
 187          */
 188         GCond *cond;
 189
 190         /**
 191          * The #music_chunk which is currently being played.  All
 192          * chunks before this one may be returned to the
 193          * #music_buffer, because they are not going to be used by
 194          * this output anymore.
 195          */
 196         const struct music_chunk *chunk;
 197
 198         /**
 199          * Has the output finished playing #chunk?
 200          */
 201         bool chunk_finished;
 202 };
 203
 204 /**
 205  * Notify object used by the thread's client, i.e. we will send a
 206  * notify signal to this object, expecting the caller to wait on it.
 207  */
 208 extern struct notify audio_output_client_notify;
 209
 210 static inline bool
 211 audio_output_is_open(const struct audio_output *ao)
 212 {
 213         return ao->open;
 214 }
 215
 216 static inline bool
 217 audio_output_command_is_finished(const struct audio_output *ao)
 218 {
 219         return ao->command == AO_COMMAND_NONE;
 220 }
 221
 222 #endif