[vlmc-devel] commit: MetadataWorker: Don't hang if the file has no length. ( Hugo Beauzée-Luyssen )

[git at videolan.org]

vlmc | branch: master | Hugo Beauzée-Luyssen <beauze.h at gmail.com> | Thu Jul  1 17:32:19 2010 +0200| [1a0b7c659e4cfe70c6e2cc4616cd9af8217f4277] | committer: Hugo Beauzée-Luyssen 

MetadataWorker: Don't hang if the file has no length.

> http://git.videolan.org/gitweb.cgi/vlmc.git/?a=commit;h=1a0b7c659e4cfe70c6e2cc4616cd9af8217f4277
---

 src/Metadata/MetaDataWorker.cpp |   23 +++++++++++++++++++++++
 src/Metadata/MetaDataWorker.h   |    4 ++++
 2 files changed, 27 insertions(+), 0 deletions(-)

diff --git a/src/Metadata/MetaDataWorker.cpp b/src/Metadata/MetaDataWorker.cpp
index 0590743..4d8091a 100644
--- a/src/Metadata/MetaDataWorker.cpp
+++ b/src/Metadata/MetaDataWorker.cpp
@@ -36,6 +36,8 @@
 # include <QImage>
 #endif
 
+#include <QTimer>
+
 MetaDataWorker::MetaDataWorker( LibVLCpp::MediaPlayer* mediaPlayer, Media* media ) :
         m_mediaPlayer( mediaPlayer ),
         m_media( media ),
@@ -43,10 +45,13 @@ MetaDataWorker::MetaDataWorker( LibVLCpp::MediaPlayer* mediaPlayer, Media* media
         m_lengthHasChanged( false ),
         m_audioBuffer( NULL )
 {
+    m_lengthChangedTimer = new QTimer;
+    m_lengthChangedTimer->setSingleShot( true );
 }
 
 MetaDataWorker::~MetaDataWorker()
 {
+    delete m_lengthChangedTimer;
     if ( m_audioBuffer )
         delete m_audioBuffer;
 }
@@ -62,11 +67,14 @@ MetaDataWorker::compute()
 
     m_media->addConstantParam( ":vout=dummy" );
     m_mediaPlayer->setMedia( m_media->vlcMedia() );
+    connect( m_lengthChangedTimer, SIGNAL( timeout() ),
+             this, SLOT( lengthChangedTimeout() ), Qt::QueuedConnection );
     connect( m_mediaPlayer, SIGNAL( playing() ),
              this, SLOT( entrypointPlaying() ), Qt::QueuedConnection );
     connect( m_mediaPlayer, SIGNAL( errorEncountered() ), this, SLOT( failure() ) );
     connect( m_mediaPlayer, SIGNAL( endReached() ), this, SLOT( failure() ) );
     m_mediaPlayer->play();
+    m_lengthChangedTimer->start( 3000 );
     m_media->flushVolatileParameters();
 }
 
@@ -201,10 +209,25 @@ MetaDataWorker::finalize()
 }
 
 void
+MetaDataWorker::lengthChangedTimeout()
+{
+    //No race condition possible, since both lengthChanged methods are called from the Qt event loop.
+    m_lengthChangedTimer->disconnect();
+    if ( m_lengthHasChanged == true )
+        return ; //This should never happen as this slot is beeing disconnected if a real length is computed.
+    disconnect( m_mediaPlayer, SIGNAL( lengthChanged( qint64 ) ),
+                this, SLOT( entrypointLengthChanged( qint64 ) ) );
+    m_lengthHasChanged = true;
+    if ( m_mediaIsPlaying == true )
+        metaDataAvailable();
+}
+
+void
 MetaDataWorker::entrypointLengthChanged( qint64 newLength )
 {
     if ( newLength <= 0 )
         return ;
+    m_lengthChangedTimer->disconnect();
     disconnect( m_mediaPlayer, SIGNAL( lengthChanged( qint64 ) ),
                 this, SLOT( entrypointLengthChanged( qint64 ) ) );
     m_lengthHasChanged = true;
diff --git a/src/Metadata/MetaDataWorker.h b/src/Metadata/MetaDataWorker.h
index 6795cdb..9281179 100644
--- a/src/Metadata/MetaDataWorker.h
+++ b/src/Metadata/MetaDataWorker.h
@@ -31,6 +31,8 @@
 #include <QTemporaryFile>
 #include <QTime>
 
+class   QTimer;
+
 namespace LibVLCpp
 {
     class   MediaPlayer;
@@ -70,10 +72,12 @@ class MetaDataWorker : public QObject
 
         unsigned char*              m_audioBuffer;
         QTime                       m_timer;
+        QTimer                      *m_lengthChangedTimer;
 
     private slots:
         void    entrypointPlaying();
         void    entrypointLengthChanged( qint64 );
+        void    lengthChangedTimeout();
 //        void    generateAudioSpectrum();
         void    failure();