Make sure delayed events are cancelled when a state machine halts

Otherwise the events might creep into the event loop if the state
machine is restarted.

Reviewed-by: Eskil Abrahamsen Blomfeldt

2 files changed, 21 insertions, 0 deletions

diff --git a/src/corelib/statemachine/qstatemachine.cpp b/src/corelib/statemachine/qstatemachine.cpp
index 256763bcbf..c7144e493c 100644
--- a/src/corelib/statemachine/qstatemachine.cpp
+++ b/src/corelib/statemachine/qstatemachine.cpp
@@ -1265,11 +1265,13 @@ void QStateMachinePrivate::_q_process()
         break;
     case Finished:
         state = NotRunning;
+        cancelAllDelayedEvents();
         unregisterAllTransitions();
         emit q->finished();
         break;
     case Stopped:
         state = NotRunning;
+        cancelAllDelayedEvents();
         unregisterAllTransitions();
         emit q->stopped();
         break;
@@ -1291,6 +1293,19 @@ void QStateMachinePrivate::processEvents(EventProcessingMode processingMode)
     }
 }
 
+void QStateMachinePrivate::cancelAllDelayedEvents()
+{
+    Q_Q(QStateMachine);
+    QHash<int, QEvent*>::const_iterator it;
+    for (it = delayedEvents.constBegin(); it != delayedEvents.constEnd(); ++it) {
+        int id = it.key();
+        QEvent *e = it.value();
+        q->killTimer(id);
+        delete e;
+    }
+    delayedEvents.clear();
+}
+
 namespace {
 
 class GoToStateTransition : public QAbstractTransition
@@ -1946,6 +1961,11 @@ bool QStateMachine::event(QEvent *e)
     if (e->type() == QEvent::Timer) {
         QTimerEvent *te = static_cast<QTimerEvent*>(e);
         int tid = te->timerId();
+        if (d->state != QStateMachinePrivate::Running) {
+            // This event has been cancelled already
+            Q_ASSERT(!d->delayedEvents.contains(tid));
+            return true;
+        }
         QEvent *ee = d->delayedEvents.take(tid);
         if (ee != 0) {
             killTimer(tid);
diff --git a/src/corelib/statemachine/qstatemachine_p.h b/src/corelib/statemachine/qstatemachine_p.h
index 141bc5c65d..cf7a073369 100644
--- a/src/corelib/statemachine/qstatemachine_p.h
+++ b/src/corelib/statemachine/qstatemachine_p.h
@@ -160,6 +160,7 @@ public:
     void handleTransitionSignal(QObject *sender, int signalIndex,
                                 void **args);    
     void processEvents(EventProcessingMode processingMode);
+    void cancelAllDelayedEvents();
     
 #ifndef QT_NO_PROPERTIES
     typedef QPair<QObject *, QByteArray> RestorableId;