Support more than 62 instances of QWinEventNotifier

QWinEventNotifiers were limited to 62 instances, because of
WaitForMultipleObject's limitation to MAXIMUM_WAIT_OBJECTS - 1 handles.

Use the RegisterWaitForSingleObject API which does not have this
restriction and executes waits in threads managed by the system. A
central manual reset event per event dispatcher is signaled in the
RegisterWaitForSingleObject callback and waited for in the event loop.

[ChangeLog][QtCore][QWinEventNotifier] QWinEventNotifier is not
restricted to 62 instances anymore.

Task-number: QTBUG-8819
Change-Id: I2c749951453a4b699cc50dada0d6017440b67a4a
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/corelib/kernel/qeventdispatcher_win_p.h b/src/corelib/kernel/qeventdispatcher_win_p.h
index f6d1bffdf5..683c7f8f36 100644
--- a/src/corelib/kernel/qeventdispatcher_win_p.h
+++ b/src/corelib/kernel/qeventdispatcher_win_p.h
@@ -161,6 +161,7 @@ class Q_CORE_EXPORT QEventDispatcherWin32Private : public QAbstractEventDispatch
 public:
     QEventDispatcherWin32Private();
     ~QEventDispatcherWin32Private();
+    static QEventDispatcherWin32Private *get(QEventDispatcherWin32 *q) { return q->d_func(); }
 
     DWORD threadId;
 
@@ -192,6 +193,7 @@ public:
     void postActivateSocketNotifiers();
     void doWsaAsyncSelect(int socket, long event);
 
+    HANDLE winEventNotifierActivatedEvent;
     QList<QWinEventNotifier *> winEventNotifierList;
     void activateEventNotifier(QWinEventNotifier * wen);