winrt: Fix two possible null pointer exceptions

If camera state is changed rapidly these can occur.

Change-Id: Ia9ccf9e03162350cd411ff9fc059c14f47b9a42e
Reviewed-by: Oliver Wolff <oliver.wolff@theqtcompany.com>
Reviewed-by: Andrew Knight <andrew.knight@intopalo.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/src/plugins/winrt/qwinrtcameracontrol.cpp b/src/plugins/winrt/qwinrtcameracontrol.cpp
index d20955da3..3489048d8 100644
--- a/src/plugins/winrt/qwinrtcameracontrol.cpp
+++ b/src/plugins/winrt/qwinrtcameracontrol.cpp
@@ -445,7 +445,7 @@ public:
     {
         m_stream->Flush();
         m_videoRenderer->setActive(false);
-        return m_presentationClock->Stop();
+        return m_presentationClock ? m_presentationClock->Stop() : S_OK;
     }
 
     HRESULT __stdcall OnClockStart(MFTIME systemTime, LONGLONG clockStartOffset) Q_DECL_OVERRIDE
@@ -624,8 +624,10 @@ void QWinRTCameraControl::setState(QCamera::State state)
             if (FAILED(hr))
                 emit error(QCamera::InvalidRequestError, qt_error_string(hr));
 
-            d->mediaSink->Shutdown();
-            d->mediaSink.Reset();
+            if (d->mediaSink) {
+                d->mediaSink->Shutdown();
+                d->mediaSink.Reset();
+            }
 
             d->state = QCamera::LoadedState;
             emit stateChanged(d->state);