mpd/src/mixer/MixerControl.cxx
2016-09-09 14:44:15 +02:00

152 lines
2.8 KiB
C++

/*
* Copyright 2003-2016 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.
*/
#include "config.h"
#include "MixerControl.hxx"
#include "MixerInternal.hxx"
#include <assert.h>
Mixer *
mixer_new(EventLoop &event_loop,
const MixerPlugin &plugin, AudioOutput &ao,
MixerListener &listener,
const ConfigBlock &block)
{
Mixer *mixer = plugin.init(event_loop, ao, listener, block);
assert(mixer == nullptr || mixer->IsPlugin(plugin));
return mixer;
}
void
mixer_free(Mixer *mixer)
{
assert(mixer != nullptr);
/* mixers with the "global" flag set might still be open at
this point (see mixer_auto_close()) */
mixer_close(mixer);
delete mixer;
}
void
mixer_open(Mixer *mixer)
{
assert(mixer != nullptr);
const ScopeLock protect(mixer->mutex);
if (mixer->open)
return;
try {
mixer->Open();
mixer->open = true;
mixer->failed = false;
} catch (...) {
mixer->failed = true;
throw;
}
}
static void
mixer_close_internal(Mixer *mixer)
{
assert(mixer != nullptr);
assert(mixer->open);
mixer->Close();
mixer->open = false;
}
void
mixer_close(Mixer *mixer)
{
assert(mixer != nullptr);
const ScopeLock protect(mixer->mutex);
if (mixer->open)
mixer_close_internal(mixer);
}
void
mixer_auto_close(Mixer *mixer)
{
if (!mixer->plugin.global)
mixer_close(mixer);
}
/*
* Close the mixer due to failure. The mutex must be locked before
* calling this function.
*/
static void
mixer_failed(Mixer *mixer)
{
assert(mixer->open);
mixer_close_internal(mixer);
mixer->failed = true;
}
int
mixer_get_volume(Mixer *mixer)
{
int volume;
assert(mixer != nullptr);
if (mixer->plugin.global && !mixer->failed)
mixer_open(mixer);
const ScopeLock protect(mixer->mutex);
if (mixer->open) {
try {
volume = mixer->GetVolume();
} catch (...) {
mixer_failed(mixer);
throw;
}
} else
volume = -1;
return volume;
}
void
mixer_set_volume(Mixer *mixer, unsigned volume)
{
assert(mixer != nullptr);
assert(volume <= 100);
if (mixer->plugin.global && !mixer->failed)
mixer_open(mixer);
const ScopeLock protect(mixer->mutex);
if (mixer->open)
mixer->SetVolume(volume);
}