winrt: Add error handling for GeoPositionInfoSource creation

If something goes wrong while creating the source, the factory should
return a nullptr (same as in QGeoPositionInfoSourceFactoryGipsy). One
such error might be, that access to location is denied on first
application start.

Task-number: QTBUG-60299
Change-Id: I50e87895a74bcff856aa29a195762a83466bc5b9
Reviewed-by: Maurice Kalinowski <maurice.kalinowski@qt.io>

3 files changed, 26 insertions, 8 deletions

diff --git a/src/plugins/position/winrt/qgeopositioninfosource_winrt.cpp b/src/plugins/position/winrt/qgeopositioninfosource_winrt.cpp
index 32a20a16..87e350dd 100644
--- a/src/plugins/position/winrt/qgeopositioninfosource_winrt.cpp
+++ b/src/plugins/position/winrt/qgeopositioninfosource_winrt.cpp
@@ -97,8 +97,19 @@ QGeoPositionInfoSourceWinRT::QGeoPositionInfoSourceWinRT(QObject *parent)
     d->updatesOngoing = false;
 
     qRegisterMetaType<QGeoPositionInfo>();
+}
+
+QGeoPositionInfoSourceWinRT::~QGeoPositionInfoSourceWinRT()
+{
+}
 
-    requestAccess();
+int QGeoPositionInfoSourceWinRT::init()
+{
+    Q_D(QGeoPositionInfoSourceWinRT);
+    if (!requestAccess()) {
+        qWarning ("Location access failed.");
+        return -1;
+    }
     HRESULT hr = QEventDispatcherWinRT::runOnXamlThread([this, d]() {
         HRESULT hr = RoActivateInstance(HString::MakeReference(RuntimeClass_Windows_Devices_Geolocation_Geolocator).Get(),
                                         &d->locator);
@@ -114,13 +125,17 @@ QGeoPositionInfoSourceWinRT::QGeoPositionInfoSourceWinRT(QObject *parent)
 
         return hr;
     });
-    Q_ASSERT_SUCCEEDED(hr);
+    if (FAILED(hr)) {
+        setError(QGeoPositionInfoSource::UnknownSourceError);
+        qErrnoWarning(hr, "Could not register status changed callback");
+        return -1;
+    }
 
     hr = d->locator->put_DesiredAccuracy(PositionAccuracy::PositionAccuracy_Default);
     if (FAILED(hr)) {
         setError(QGeoPositionInfoSource::UnknownSourceError);
         qErrnoWarning(hr, "Could not initialize desired accuracy.");
-        return;
+        return -1;
     }
 
     d->positionToken.value = 0;
@@ -135,10 +150,7 @@ QGeoPositionInfoSourceWinRT::QGeoPositionInfoSourceWinRT(QObject *parent)
     setPreferredPositioningMethods(QGeoPositionInfoSource::AllPositioningMethods);
 
     connect(this, &QGeoPositionInfoSourceWinRT::nativePositionUpdate, this, &QGeoPositionInfoSourceWinRT::updateSynchronized);
-}
-
-QGeoPositionInfoSourceWinRT::~QGeoPositionInfoSourceWinRT()
-{
+    return 0;
 }
 
 QGeoPositionInfo QGeoPositionInfoSourceWinRT::lastKnownPosition(bool fromSatellitePositioningMethodsOnly) const
diff --git a/src/plugins/position/winrt/qgeopositioninfosource_winrt_p.h b/src/plugins/position/winrt/qgeopositioninfosource_winrt_p.h
index b8820dd2..9f3a1c7f 100644
--- a/src/plugins/position/winrt/qgeopositioninfosource_winrt_p.h
+++ b/src/plugins/position/winrt/qgeopositioninfosource_winrt_p.h
@@ -78,6 +78,7 @@ class QGeoPositionInfoSourceWinRT : public QGeoPositionInfoSource
 public:
     QGeoPositionInfoSourceWinRT(QObject *parent = 0);
     ~QGeoPositionInfoSourceWinRT();
+    int init();
 
     QGeoPositionInfo lastKnownPosition(bool fromSatellitePositioningMethodsOnly = false) const;
     PositioningMethods supportedPositioningMethods() const;
diff --git a/src/plugins/position/winrt/qgeopositioninfosourcefactory_winrt.cpp b/src/plugins/position/winrt/qgeopositioninfosourcefactory_winrt.cpp
index 81656c21..e58744a0 100644
--- a/src/plugins/position/winrt/qgeopositioninfosourcefactory_winrt.cpp
+++ b/src/plugins/position/winrt/qgeopositioninfosourcefactory_winrt.cpp
@@ -39,7 +39,12 @@
 
 QGeoPositionInfoSource *QGeoPositionInfoSourceFactoryWinRT::positionInfoSource(QObject *parent)
 {
-    return new QGeoPositionInfoSourceWinRT(parent);
+    QGeoPositionInfoSourceWinRT *src = new QGeoPositionInfoSourceWinRT(parent);
+    if (src->init() < 0) {
+        delete src;
+        src = 0;
+    }
+    return src;
 }
 
 QGeoSatelliteInfoSource *QGeoPositionInfoSourceFactoryWinRT::satelliteInfoSource(QObject *parent)