Make the event notification on Windows be mandatory in all dispatchers

This way, QWinEventNotifier will work on all Windows systems, not just
with the default event dispatcher. Other dispatchers (other than
QWin32EventDispatcher) are permitted, so the class should not abort just
because of that.

If a dispatcher really doesn't want to implement this, they need to
implement the virtuals to do nothing, possibly print a warning.

Change-Id: I2c132bcde95b9d5941c8906a0fcd2ad964087772
Reviewed-by: Bradley T. Hughes <bradley.hughes@nokia.com>

6 files changed, 36 insertions, 5 deletions

diff --git a/src/corelib/kernel/qabstracteventdispatcher.h b/src/corelib/kernel/qabstracteventdispatcher.h
index 96498d207d..e70530b283 100644
--- a/src/corelib/kernel/qabstracteventdispatcher.h
+++ b/src/corelib/kernel/qabstracteventdispatcher.h
@@ -53,6 +53,10 @@ QT_BEGIN_NAMESPACE
 class QAbstractEventDispatcherPrivate;
 class QSocketNotifier;
 
+#ifdef Q_OS_WIN
+class QWinEventNotifier;
+#endif
+
 class Q_CORE_EXPORT QAbstractEventDispatcher : public QObject
 {
     Q_OBJECT
@@ -95,6 +99,11 @@ public:
 
     virtual int remainingTime(int timerId) = 0;
 
+#ifdef Q_OS_WIN
+    virtual bool registerEventNotifier(QWinEventNotifier *notifier) = 0;
+    virtual void unregisterEventNotifier(QWinEventNotifier *notifier) = 0;
+#endif
+
     virtual void wakeUp() = 0;
     virtual void interrupt() = 0;
     virtual void flush() = 0;
diff --git a/src/corelib/kernel/qwineventnotifier.cpp b/src/corelib/kernel/qwineventnotifier.cpp
index b48bd0c8cc..d81d1ec460 100644
--- a/src/corelib/kernel/qwineventnotifier.cpp
+++ b/src/corelib/kernel/qwineventnotifier.cpp
@@ -134,10 +134,12 @@ QWinEventNotifier::QWinEventNotifier(HANDLE hEvent, QObject *parent)
  : QObject(*new QWinEventNotifierPrivate(hEvent, false), parent)
 {
     Q_D(QWinEventNotifier);
-    QEventDispatcherWin32 *eventDispatcher = qobject_cast<QEventDispatcherWin32 *>(d->threadData->eventDispatcher);
-    Q_ASSERT_X(eventDispatcher, "QWinEventNotifier::QWinEventNotifier()",
-               "Cannot create a win event notifier without a QEventDispatcherWin32");
-    eventDispatcher->registerEventNotifier(this);
+    QAbstractEventDispatcher *eventDispatcher = d->threadData->eventDispatcher;
+    if (!eventDispatcher) {
+        qWarning("QWinEventNotifier: Can only be used with threads started with QThread");
+    } else {
+        eventDispatcher->registerEventNotifier(this);
+    }
     d->enabled = true;
 }
 
@@ -205,7 +207,7 @@ void QWinEventNotifier::setEnabled(bool enable)
         return;
     d->enabled = enable;
 
-    QEventDispatcherWin32 *eventDispatcher = qobject_cast<QEventDispatcherWin32 *>(d->threadData->eventDispatcher);
+    QAbstractEventDispatcher *eventDispatcher = d->threadData->eventDispatcher;
     if (!eventDispatcher) // perhaps application is shutting down
         return;
 
diff --git a/tests/auto/corelib/kernel/qcoreapplication/tst_qcoreapplication.cpp b/tests/auto/corelib/kernel/qcoreapplication/tst_qcoreapplication.cpp
index e8f6c29a94..2ac075bebf 100644
--- a/tests/auto/corelib/kernel/qcoreapplication/tst_qcoreapplication.cpp
+++ b/tests/auto/corelib/kernel/qcoreapplication/tst_qcoreapplication.cpp
@@ -622,6 +622,11 @@ public:
     void interrupt() {}
     void flush() {}
 
+#ifdef Q_OS_WIN
+    bool registerEventNotifier(QWinEventNotifier *) { return false; }
+    void unregisterEventNotifier(QWinEventNotifier *) { }
+#endif
+
     bool visited;
 };
 
diff --git a/tests/auto/corelib/thread/qthread/tst_qthread.cpp b/tests/auto/corelib/thread/qthread/tst_qthread.cpp
index 41cfc52354..da49f43b7d 100644
--- a/tests/auto/corelib/thread/qthread/tst_qthread.cpp
+++ b/tests/auto/corelib/thread/qthread/tst_qthread.cpp
@@ -1239,6 +1239,11 @@ public:
     void interrupt() {}
     void flush() {}
 
+#ifdef Q_OS_WIN
+    bool registerEventNotifier(QWinEventNotifier *) { return false; }
+    void unregisterEventNotifier(QWinEventNotifier *) { }
+#endif
+
     bool visited;
 };
 
diff --git a/tests/auto/testlib/selftests/benchlibeventcounter/tst_benchlibeventcounter.cpp b/tests/auto/testlib/selftests/benchlibeventcounter/tst_benchlibeventcounter.cpp
index 82de653586..b077291cc6 100644
--- a/tests/auto/testlib/selftests/benchlibeventcounter/tst_benchlibeventcounter.cpp
+++ b/tests/auto/testlib/selftests/benchlibeventcounter/tst_benchlibeventcounter.cpp
@@ -64,6 +64,11 @@ public:
     bool unregisterTimers(QObject*) { return false; }
     int remainingTime(int) { return 0; }
     void wakeUp() {}
+
+#ifdef Q_OS_WIN
+    bool registerEventNotifier(QWinEventNotifier *) { return false; }
+    void unregisterEventNotifier(QWinEventNotifier *) { }
+#endif
 };
 
 class tst_BenchlibEventCounter: public QObject
diff --git a/tests/auto/testlib/selftests/benchliboptions/tst_benchliboptions.cpp b/tests/auto/testlib/selftests/benchliboptions/tst_benchliboptions.cpp
index d3be93b715..7673aa396e 100644
--- a/tests/auto/testlib/selftests/benchliboptions/tst_benchliboptions.cpp
+++ b/tests/auto/testlib/selftests/benchliboptions/tst_benchliboptions.cpp
@@ -64,6 +64,11 @@ public:
     bool unregisterTimers(QObject*) { return false; }
     int remainingTime(int) { return 0; }
     void wakeUp() {}
+
+#ifdef Q_OS_WIN
+    bool registerEventNotifier(QWinEventNotifier *) { return false; }
+    void unregisterEventNotifier(QWinEventNotifier *) { }
+#endif
 };
 
 class tst_BenchlibOptions: public QObject