Cocoa: clear queued user input events when window is destroyed

QCocoaEventDispatcher stores user input events in a queue in certain
cases. If the target of those events is destroyed, the events are later
sent to the stale window, causing a crash.

Task-number: QTBUG-39211
Change-Id: Ie55d2df5697c742bcb644ebf8c5028015a0b8148
Reviewed-by: Morten Johan Sørvig <morten.sorvig@digia.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/src/plugins/platforms/cocoa/qcocoaeventdispatcher.mm b/src/plugins/platforms/cocoa/qcocoaeventdispatcher.mm
index 45c0714b6b..e7f8992c6d 100644
--- a/src/plugins/platforms/cocoa/qcocoaeventdispatcher.mm
+++ b/src/plugins/platforms/cocoa/qcocoaeventdispatcher.mm
@@ -892,6 +892,21 @@ void QCocoaEventDispatcherPrivate::processPostedEvents()
     }
 }
 
+void QCocoaEventDispatcherPrivate::removeQueuedUserInputEvents(int nsWinNumber)
+{
+    if (nsWinNumber) {
+        int eventIndex = queuedUserInputEvents.size();
+
+        while (--eventIndex >= 0) {
+            NSEvent * nsevent = static_cast<NSEvent *>(queuedUserInputEvents.at(eventIndex));
+            if ([nsevent windowNumber] == nsWinNumber) {
+                queuedUserInputEvents.removeAt(eventIndex);
+                [nsevent release];
+            }
+        }
+    }
+}
+
 void QCocoaEventDispatcherPrivate::firstLoopEntry(CFRunLoopObserverRef ref,
                                                 CFRunLoopActivity activity,
                                                 void *info)