auto-saves every minute and recovers upon crash

auto-save time is not configurable yet. saves "recover.mmp" to
WORKING_DIR every 60 seconds. Deletes recover.mmp on successful
close of LMMS. If recover.mmp is found upon start, it loads that
project.
(cherry picked from comit f73ccadc17)

include/MainWindow.h

@@ -27,6 +27,7 @@
 #define _MAIN_WINDOW_H
 
 #include <QtCore/QBasicTimer>
+#include <QtCore/QTimer>
 #include <QtCore/QList>
 #include <QtGui/QMainWindow>
 #include <QtGui/QWhatsThis>
@@ -160,6 +161,7 @@ private:
 	QList<PluginView *> m_tools;
 
 	QBasicTimer m_updateTimer;
+	QTimer m_autoSaveTimer;
 
 
 	friend class engine;
@@ -173,6 +175,8 @@ private slots:
 	void updateRecentlyOpenedProjectsMenu( void );
 
 
+	void autoSave();
+
 signals:
 	void periodicUpdate( void );
 

src/core/main.cpp

@@ -25,6 +25,7 @@
 #include "lmmsconfig.h"
 #include "lmmsversion.h"
 
+#include <QtCore/QDir>
 #include <QtCore/QFileInfo>
 #include <QtCore/QLocale>
 #include <QtCore/QProcess>
@@ -414,6 +415,13 @@ int main( int argc, char * * argv )
 		// srandom() calls in their init procedure
 		srand( getpid() + time( 0 ) );
 
+		// recover a file?
+		QString recoveryFile = QDir(configManager::inst()->workingDir()).absoluteFilePath("recover.mmp");
+		if( QFileInfo(recoveryFile).exists() )
+		{
+			file_to_load = recoveryFile;
+		}
+
 		// we try to load given file
 		if( !file_to_load.isEmpty() )
 		{

src/gui/MainWindow.cpp

@@ -72,7 +72,8 @@ MainWindow::MainWindow( void ) :
 	m_workspace( NULL ),
 	m_templatesMenu( NULL ),
 	m_recentlyOpenedProjectsMenu( NULL ),
-	m_toolsMenu( NULL )
+	m_toolsMenu( NULL ),
+	m_autoSaveTimer( this )
 {
 	setAttribute( Qt::WA_DeleteOnClose );
 
@@ -182,6 +183,10 @@ MainWindow::MainWindow( void ) :
 
 
 	m_updateTimer.start( 1000 / 20, this );	// 20 fps
+
+	// connect auto save
+	connect(&m_autoSaveTimer, SIGNAL(timeout()), this, SLOT(autoSave()));
+	m_autoSaveTimer.start(1000 * 60); // 1 minute
 }
 
 
@@ -898,6 +903,9 @@ void MainWindow::closeEvent( QCloseEvent * _ce )
 {
 	if( mayChangeProject() )
 	{
+		// delete recovery file
+		QDir working(configManager::inst()->workingDir());
+		working.remove("recover.mmp");
 		_ce->accept();
 	}
 	else
@@ -969,7 +977,7 @@ void MainWindow::keyReleaseEvent( QKeyEvent * _ke )
 
 
 
-void MainWindow::timerEvent( QTimerEvent * )
+void MainWindow::timerEvent( QTimerEvent * _te)
 {
 	emit periodicUpdate();
 }
@@ -1037,6 +1045,13 @@ void MainWindow::browseHelp( void )
 
 
 
+void MainWindow::autoSave()
+{
+	QDir work(configManager::inst()->workingDir());
+	engine::getSong()->saveProjectAs(work.absoluteFilePath("recover.mmp"));
+}
+
+
 #include "moc_MainWindow.cxx"