Failure free restart of the launcher and a comment

why we do that

3 files changed, 28 insertions, 0 deletions

diff --git a/core/launcher/serverapp.cpp b/core/launcher/serverapp.cpp
index 522ef07..28316a4 100644
--- a/core/launcher/serverapp.cpp
+++ b/core/launcher/serverapp.cpp
@@ -714,27 +714,46 @@ void ServerApplication::shutdown( ShutdownImpl::Type t )
         // clipboard applet has to stop its poll timer, or Qt/E
         // will hang on quit() right before it emits aboutToQuit()
         emit aboutToQuit ( );
 
         quit();
         break;
     }
 }
 
 void ServerApplication::restart()
 {
     if ( allowRestart ) {
+
+        /*
+         * Applets and restart is a problem. Some applets delete
+         * their widgets even if ownership gets transfered to the
+         * parent (Systray ) but deleting the applet may be unsafe
+         * as well ( double deletion ). Some have topLevel widgets
+         * and when we dlclose and then delete the widget we will
+         * crash and an crash during restart is not nice
+         */
+#ifdef ALL_APPLETS_ON_THIS_WORLD_ARE_FIXED
+        /* same as above */
+        emit aboutToQuit();
 	prepareForTermination(TRUE);
 	doRestart = TRUE;
 	quit();
+#else
+        prepareForTermination( true );
+        for ( int fd = 3; fd < 100; fd++ )
+		close( fd );
+        execl( ( qpeDir() + "/bin/qpe" ).latin1(), "qpe", 0 );
+        exit( 1 );
+#endif
     }
 }
 
 void ServerApplication::rereadVolumes()
 {
     Config cfg( "qpe" );
     cfg. setGroup ( "Volume" );
 
     m_screentap_sound = cfg. readBoolEntry ( "TouchSound" );
     m_keyclick_sound  = cfg. readBoolEntry ( "KeySound" );
     m_alarm_sound     = cfg. readBoolEntry ( "AlarmSound" );
 }
diff --git a/core/launcher/systray.cpp b/core/launcher/systray.cpp
index 64356ca..6122770 100644
--- a/core/launcher/systray.cpp
+++ b/core/launcher/systray.cpp
@@ -60,24 +60,32 @@ static int compareAppletPositions(const void *a, const void *b)
 
 void SysTray::loadApplets()
 {
     hide();
     clearApplets();
     addApplets();
 }
 
 void SysTray::clearApplets()
 {
 #ifndef QT_NO_COMPONENTS
 
+    /*
+     * Note on clearing. SOme applets delete their
+     * applets themselves some don't do it
+     * and on restart this can crash. If we delete it
+     * here we might end up in a double deletion. We could
+     * use QGuardedPtr but that would be one QOBject
+     * for every applet more but only useful for restart
+     */
     QValueList<TaskbarApplet>::Iterator mit;
     for ( mit = appletList.begin(); mit != appletList.end(); ++mit ) {
         (*mit).iface->release();
 	(*mit).library->unload();
 	delete (*mit).library;
     }
 
 #endif
     appletList.clear();
     if ( layout )
 	delete layout;
     layout = new QHBoxLayout( this, 0, 1 );
diff --git a/core/launcher/systray.h b/core/launcher/systray.h
index 77c581f..b989d58 100644
--- a/core/launcher/systray.h
+++ b/core/launcher/systray.h
@@ -18,24 +18,25 @@
 **
 **********************************************************************/
 
 #ifndef __SYSTRAY_H__
 #define __SYSTRAY_H__
 
 #ifndef QT_NO_COMPONENT
 #include <qtopia/taskbarappletinterface.h>
 #endif
 
 #include <qframe.h>
 #include <qvaluelist.h>
+#include <qguardedptr.h>
 
 class QHBoxLayout;
 class QLibrary;
 
 struct TaskbarApplet
 {
 #ifndef QT_NO_COMPONENT
     QLibrary *library;
     TaskbarAppletInterface *iface;
 #endif
     QWidget *applet;
     QString name;