src/mixer_all.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 /** \file
  21  *
  22  * Functions which affect the mixers of all audio outputs.
  23  */
  24
  25 #ifndef MPD_MIXER_ALL_H
  26 #define MPD_MIXER_ALL_H
  27
  28 #include <stdbool.h>
  29
  30 /**
  31  * Returns the average volume of all available mixers (range 0..100).
  32  * Returns -1 if no mixer can be queried.
  33  */
  34 int
  35 mixer_all_get_volume(void);
  36
  37 /**
  38  * Sets the volume on all available mixers.
  39  *
  40  * @param volume the volume (range 0..100)
  41  * @return true on success, false on failure
  42  */
  43 bool
  44 mixer_all_set_volume(unsigned volume);
  45
  46 /**
  47  * Similar to mixer_all_get_volume(), but gets the volume only for
  48  * software mixers.  See #software_mixer_plugin.  This function fails
  49  * if no software mixer is configured.
  50  */
  51 int
  52 mixer_all_get_software_volume(void);
  53
  54 /**
  55  * Similar to mixer_all_set_volume(), but sets the volume only for
  56  * software mixers.  See #software_mixer_plugin.  This function cannot
  57  * fail, because the underlying software mixers cannot fail either.
  58  */
  59 void
  60 mixer_all_set_software_volume(unsigned volume);
  61
  62 #endif