mpd/src/mixer/MixerInternal.hxx
2021-01-01 19:54:28 +01:00

99 lines
2.2 KiB
C++

/*
* Copyright 2003-2021 The Music Player Daemon Project
* http://www.musicpd.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef MPD_MIXER_INTERNAL_HXX
#define MPD_MIXER_INTERNAL_HXX
#include "MixerPlugin.hxx"
#include "MixerList.hxx"
#include "thread/Mutex.hxx"
#include "util/Compiler.h"
class MixerListener;
class Mixer {
public:
const MixerPlugin &plugin;
MixerListener &listener;
/**
* This mutex protects all of the mixer struct, including its
* implementation, so plugins don't have to deal with that.
*/
Mutex mutex;
/**
* Is the mixer device currently open?
*/
bool open = false;
/**
* Has this mixer failed, and should not be reopened
* automatically?
*/
bool failed = false;
public:
explicit Mixer(const MixerPlugin &_plugin,
MixerListener &_listener) noexcept
:plugin(_plugin), listener(_listener) {}
Mixer(const Mixer &) = delete;
virtual ~Mixer() {}
bool IsPlugin(const MixerPlugin &other) const noexcept {
return &plugin == &other;
}
/**
* Open mixer device
*
* Throws std::runtime_error on error.
*/
virtual void Open() = 0;
/**
* Close mixer device
*/
virtual void Close() noexcept = 0;
/**
* Reads the current volume.
*
* Throws std::runtime_error on error.
*
* @return the current volume (0..100 including) or -1 if
* unavailable
*/
virtual int GetVolume() = 0;
/**
* Sets the volume.
*
* Throws std::runtime_error on error.
*
* @param volume the new volume (0..100 including)
*/
virtual void SetVolume(unsigned volume) = 0;
};
#endif