Gracefully handling signals

Signed-off-by: Dušan Poizl <nou.spiro@gmail.com>

mainwindow.h

@@ -2,6 +2,7 @@
 #define MAINWINDOW_H
 
 #include <QMainWindow>
+#include <QSocketNotifier>
 #include "imageringlist.h"
 #include "imagescrollarea.h"
 #include "database.h"
@@ -14,13 +15,18 @@ class MainWindow : public QMainWindow
     Database *m_database;
     bool loading;
     int queued;
+    static int socketPair[2];
+    QSocketNotifier *socketNotifier;
 public:
     MainWindow(QWidget *parent = 0);
     ~MainWindow();
 protected:
     void keyPressEvent(QKeyEvent *event);
     void keyReleaseEvent(QKeyEvent *event);
+    void setupSigterm();
+    static void signalHandler(int);
 protected slots:
+    void socketNotify();
     void updateWindowTitle();
     void pixmapLoaded(QPixmap pix);
     void openFile();