use a comptr for the nsIRegion in nsWidget, fix a leak with lookandfeel objects in widget that both dbaron@fas.harvard.edu and I found at about the same time. and clean up more carefully and avoid processing events if we are destroyed or being destroyed to avoid those natsty lil crashes. fixes bug 20291 and 29342

widget/src/gtk/nsGtkEventHandler.cpp

@@ -773,6 +773,11 @@ handle_gdk_event (GdkEvent *event, gpointer data)
       // It was an event on one of our superwindows
 
       nsWindow *window = (nsWindow *)gtk_object_get_data (object, "nsWindow");
+
+      // if we don't have a window here anymore, we are probably in the process of being or have been destroyed
+      if (!window)
+        return;
+
       GtkWidget *current_grab = gtk_grab_get_current();
 
       // if there's a grab in progress, make sure to send it right to that widget.

widget/src/gtk/nsWidget.cpp

@@ -260,11 +260,8 @@ nsWidget::nsWidget()
   mIsDragDest = PR_FALSE;
   mIsToplevel = PR_FALSE;
 
-  if (NS_OK == nsComponentManager::CreateInstance(kRegionCID,
-                                                  nsnull,
-                                                  NS_GET_IID(nsIRegion),
-                                                  (void**)&mUpdateArea))
-  {
+  mUpdateArea = do_CreateInstance(kRegionCID);
+  if (mUpdateArea) {
     mUpdateArea->Init();
     mUpdateArea->SetTo(0, 0, 0, 0);
   }
@@ -338,13 +335,11 @@ nsWidget::~nsWidget()
   printf("nsWidget::~nsWidget:%p\n", this);
 #endif
 
-  NS_IF_RELEASE(mUpdateArea);
-
   // it's safe to always call Destroy() because it will only allow itself
   // to be called once
   Destroy();
 
-  if (!sWidgetCount--) {
+  if (!--sWidgetCount) {
     NS_IF_RELEASE(sLookAndFeel);
   }
 
@@ -424,6 +419,10 @@ NS_IMETHODIMP nsWidget::Destroy(void)
   if (mIsDestroying)
     return NS_OK;
 
+  // we don't want people sending us events if we are the button motion target
+  if (sButtonMotionTarget == this)
+    sButtonMotionTarget = nsnull;
+
   // ok, set our state
   mIsDestroying = PR_TRUE;
 
@@ -1642,6 +1641,9 @@ nsWidget::InstallRealizeSignal(GtkWidget * aWidget)
 nsWidget::OnMotionNotifySignal(GdkEventMotion * aGdkMotionEvent)
 {
   
+  if (mIsDestroying)
+    return;
+
   nsMouseEvent event;
 
   event.message = NS_MOUSE_MOVE;

widget/src/gtk/nsWidget.h

@@ -487,7 +487,7 @@ protected:
 
   // This is the composite update area (union of all the calls to
   // Invalidate)
-  nsIRegion *mUpdateArea;
+  nsCOMPtr<nsIRegion> mUpdateArea;
 
   PRBool mShown;
 

widget/src/gtk/nsWindow.cpp

@@ -165,6 +165,22 @@ nsWindow::~nsWindow()
     UnqueueDraw();
 }
 
+NS_IMETHODIMP nsWindow::Destroy(void)
+{
+  // remove our pointer from the object so that we event handlers don't send us events
+  // after we are gone or in the process of going away
+
+  if (mSuperWin)
+    gtk_object_remove_data(GTK_OBJECT(mSuperWin), "nsWindow");
+  if (mShell)
+    gtk_object_remove_data(GTK_OBJECT(mShell), "nsWindow");
+  if (mMozArea)
+    gtk_object_remove_data(GTK_OBJECT(mMozArea), "nsWindow");
+
+  return nsWidget::Destroy();
+}
+
+
 PRBool nsWindow::IsChild() const
 {
   return PR_FALSE;
@@ -1028,6 +1044,9 @@ nsWindow::InstallFocusOutSignal(GtkWidget * aWidget)
 void 
 nsWindow::HandleGDKEvent(GdkEvent *event)
 {
+  if (mIsDestroying)
+    return;
+
   switch (event->any.type)
   {
   case GDK_MOTION_NOTIFY:
@@ -2543,6 +2562,9 @@ nsWindow::HandleXlibExposeEvent(XEvent *event)
 void
 nsWindow::HandleXlibButtonEvent(XButtonEvent * aButtonEvent)
 {
+  if (mIsDestroying)
+    return;
+
   nsMouseEvent event;
   
   PRUint32 eventType = 0;

widget/src/gtk/nsWindow.h

@@ -86,6 +86,7 @@ public:
   NS_IMETHOD           SetCursor(nsCursor aCursor);
   NS_IMETHOD           SetFocus(void);
   NS_IMETHOD           GetAttention(void);
+  NS_IMETHOD           Destroy();
 
   void                 QueueDraw();
   void                 UnqueueDraw();