74 lines
2.1 KiB
C++
74 lines
2.1 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.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#pragma once
|
||
|
|
|
||
|
|
#include "system/PeriodClock.hxx"
|
||
|
|
|
||
|
|
class MultipleOutputs;
|
||
|
|
class BufferedOutputStream;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Cache for hardware/software volume levels.
|
||
|
|
*/
|
||
|
|
class MixerMemento {
|
||
|
|
unsigned volume_software_set = 100;
|
||
|
|
|
||
|
|
/** the cached hardware mixer value; invalid if negative */
|
||
|
|
int last_hardware_volume = -1;
|
||
|
|
|
||
|
|
/** the age of #last_hardware_volume */
|
||
|
|
PeriodClock hardware_volume_clock;
|
||
|
|
|
||
|
|
public:
|
||
|
|
/**
|
||
|
|
* Flush the hardware volume cache.
|
||
|
|
*/
|
||
|
|
void InvalidateHardwareVolume() noexcept {
|
||
|
|
last_hardware_volume = -1;
|
||
|
|
}
|
||
|
|
|
||
|
|
[[gnu::pure]]
|
||
|
|
int GetVolume(const MultipleOutputs &outputs) noexcept;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Throws on error.
|
||
|
|
*/
|
||
|
|
void SetVolume(MultipleOutputs &outputs, unsigned volume);
|
||
|
|
|
||
|
|
bool LoadSoftwareVolumeState(const char *line, MultipleOutputs &outputs);
|
||
|
|
|
||
|
|
void SaveSoftwareVolumeState(BufferedOutputStream &os) const;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Generates a hash number for the current state of the software
|
||
|
|
* volume control. This is used by timer_save_state_file() to
|
||
|
|
* determine whether the state has changed and the state file should
|
||
|
|
* be saved.
|
||
|
|
*/
|
||
|
|
[[gnu::pure]]
|
||
|
|
unsigned GetSoftwareVolumeStateHash() const noexcept {
|
||
|
|
return volume_software_set;
|
||
|
|
}
|
||
|
|
|
||
|
|
private:
|
||
|
|
bool SetSoftwareVolume(MultipleOutputs &outputs, unsigned volume);
|
||
|
|
void SetHardwareVolume(MultipleOutputs &outputs, unsigned volume);
|
||
|
|
};
|