Add a way for auxiliary threads to handle events without CoreApp

Long-lived threads started by Qt itself can now receive events even if
QCoreApplication hasn't been created. This is required in all threads we
start that will handle events, unless we're sure that the thread will
exit before the global application object begins destruction.

Otherwise, those threads will have race conditions dealing with the
event delivery system trying to call the QCoreApplication::notify()
virtual while the object is being destroyed.

Change-Id: I27eaacb532114dd188c4ffff13d4ad2a4bb443e6
Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com>

4 files changed, 6 insertions, 4 deletions

diff --git a/src/platformsupport/input/evdevtablet/qevdevtablet.cpp b/src/platformsupport/input/evdevtablet/qevdevtablet.cpp
index c59f0f390a..c6f952c64d 100644
--- a/src/platformsupport/input/evdevtablet/qevdevtablet.cpp
+++ b/src/platformsupport/input/evdevtablet/qevdevtablet.cpp
@@ -292,7 +292,7 @@ void QEvdevTabletHandler::readData()
 
 
 QEvdevTabletHandlerThread::QEvdevTabletHandlerThread(const QString &spec, QObject *parent)
-    : QThread(parent), m_spec(spec), m_handler(0)
+    : QDaemonThread(parent), m_spec(spec), m_handler(0)
 {
     start();
 }
diff --git a/src/platformsupport/input/evdevtablet/qevdevtablet_p.h b/src/platformsupport/input/evdevtablet/qevdevtablet_p.h
index f9682290d9..f546f9a88a 100644
--- a/src/platformsupport/input/evdevtablet/qevdevtablet_p.h
+++ b/src/platformsupport/input/evdevtablet/qevdevtablet_p.h
@@ -48,6 +48,7 @@
 #include <QObject>
 #include <QString>
 #include <QThread>
+#include <QtCore/private/qthread_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -68,7 +69,7 @@ private:
     QEvdevTabletData *d;
 };
 
-class QEvdevTabletHandlerThread : public QThread
+class QEvdevTabletHandlerThread : public QDaemonThread
 {
 public:
     explicit QEvdevTabletHandlerThread(const QString &spec, QObject *parent = 0);
diff --git a/src/platformsupport/input/evdevtouch/qevdevtouchhandler.cpp b/src/platformsupport/input/evdevtouch/qevdevtouchhandler.cpp
index 1556be5cc1..1ca95074b9 100644
--- a/src/platformsupport/input/evdevtouch/qevdevtouchhandler.cpp
+++ b/src/platformsupport/input/evdevtouch/qevdevtouchhandler.cpp
@@ -642,7 +642,7 @@ void QEvdevTouchScreenData::reportPoints()
 
 
 QEvdevTouchScreenHandlerThread::QEvdevTouchScreenHandlerThread(const QString &device, const QString &spec, QObject *parent)
-    : QThread(parent), m_device(device), m_spec(spec), m_handler(0)
+    : QDaemonThread(parent), m_device(device), m_spec(spec), m_handler(0)
 {
     start();
 }
diff --git a/src/platformsupport/input/evdevtouch/qevdevtouchhandler_p.h b/src/platformsupport/input/evdevtouch/qevdevtouchhandler_p.h
index a6d3a860f5..8e7dfe59bb 100644
--- a/src/platformsupport/input/evdevtouch/qevdevtouchhandler_p.h
+++ b/src/platformsupport/input/evdevtouch/qevdevtouchhandler_p.h
@@ -49,6 +49,7 @@
 #include <QString>
 #include <QList>
 #include <QThread>
+#include <QtCore/private/qthread_p.h>
 #include <qpa/qwindowsysteminterface.h>
 
 #if !defined(QT_NO_MTDEV)
@@ -80,7 +81,7 @@ private:
 #endif
 };
 
-class QEvdevTouchScreenHandlerThread : public QThread
+class QEvdevTouchScreenHandlerThread : public QDaemonThread
 {
 public:
     explicit QEvdevTouchScreenHandlerThread(const QString &device, const QString &spec, QObject *parent = 0);