mirror of
https://github.com/xiaoyifang/goldendict-ng.git
synced 2024-11-23 20:14:05 +00:00
92 lines
2.8 KiB
C++
92 lines
2.8 KiB
C++
/* This file is (c) 2018 Igor Kushnir <igorkuo@gmail.com>
|
|
* Part of GoldenDict. Licensed under GPLv3 or later, see the LICENSE file */
|
|
|
|
#include "externalaudioplayer.hh"
|
|
#include "externalviewer.hh"
|
|
|
|
ExternalAudioPlayer::ExternalAudioPlayer():
|
|
exitingViewer( 0 )
|
|
{
|
|
}
|
|
|
|
ExternalAudioPlayer::~ExternalAudioPlayer()
|
|
{
|
|
// Destroy viewers immediately to prevent memory and temporary file leaks
|
|
// at application exit.
|
|
|
|
// Set viewer to null first and foremost to make sure that onViewerDestroyed()
|
|
// doesn't attempt to start viewer or mess the smart pointer up.
|
|
stopAndDestroySynchronously( viewer.release() );
|
|
|
|
stopAndDestroySynchronously( exitingViewer );
|
|
}
|
|
|
|
void ExternalAudioPlayer::setPlayerCommandLine( QString const & playerCommandLine_ )
|
|
{
|
|
playerCommandLine = playerCommandLine_;
|
|
}
|
|
|
|
QString ExternalAudioPlayer::play( const char * data, int size )
|
|
{
|
|
stop();
|
|
|
|
Q_ASSERT( !viewer && "viewer must be null at this point for exception safety." );
|
|
try {
|
|
// Our destructor properly destroys viewers we remember about.
|
|
// In the unlikely case that we call viewer.reset() during the application
|
|
// exit, ~QObject() prevents leaks as this class is a parent of all viewers.
|
|
viewer.reset( new ExternalViewer( data, size, "wav", playerCommandLine, this ) );
|
|
}
|
|
catch ( const ExternalViewer::Ex & e ) {
|
|
return e.what();
|
|
}
|
|
|
|
if ( exitingViewer )
|
|
return QString(); // Will start later.
|
|
return startViewer();
|
|
}
|
|
|
|
void ExternalAudioPlayer::stop()
|
|
{
|
|
if ( !exitingViewer && viewer && !viewer->stop() ) {
|
|
// Give the previous viewer a chance to stop before starting a new one.
|
|
// This prevents overlapping audio and possible conflicts between
|
|
// external program instances.
|
|
// Graceful stopping is better than calling viewer.reset() because:
|
|
// 1) the process gets a chance to clean up and save its state;
|
|
// 2) there is no event loop blocking and consequently no (short) UI freeze
|
|
// while synchronously waiting for the external process to exit.
|
|
exitingViewer = viewer.release();
|
|
}
|
|
else // viewer is either not started or already stopped -> simply destroy it.
|
|
viewer.reset();
|
|
}
|
|
|
|
void ExternalAudioPlayer::onViewerDestroyed( QObject * destroyedViewer )
|
|
{
|
|
if ( exitingViewer == destroyedViewer ) {
|
|
exitingViewer = 0;
|
|
if ( viewer ) {
|
|
QString errorMessage = startViewer();
|
|
if ( !errorMessage.isEmpty() )
|
|
emit error( errorMessage );
|
|
}
|
|
}
|
|
else if ( viewer.get() == destroyedViewer )
|
|
viewer.reset( nullptr ); // viewer finished and died -> reset
|
|
}
|
|
|
|
QString ExternalAudioPlayer::startViewer()
|
|
{
|
|
Q_ASSERT( !exitingViewer && viewer );
|
|
connect( viewer.get(), &QObject::destroyed, this, &ExternalAudioPlayer::onViewerDestroyed );
|
|
try {
|
|
viewer->start();
|
|
}
|
|
catch ( const ExternalViewer::Ex & e ) {
|
|
viewer.reset();
|
|
return e.what();
|
|
}
|
|
return QString();
|
|
}
|