Fix QAudioSink on Windows and make the auto tests pass

Windows tests became working, but on CI they are still
not available since there're no audio devices on Win CI.

- use QPointer for IO device
  (a corner case for close() in the destructor)
- fix the method reset(), it should close the sink and
  change the state
- There's a bunch of futher improvements to be done,
  namely, stop() should be improved for having more
  accurate behavior.

Change-Id: I575a1d97d6d07564164c8b2de91166315d8f28d7
Reviewed-by: Lars Knoll <lars@knoll.priv.no>
(cherry picked from commit 44067974d2ba15c323f8146d619f67390d3042b8)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

2 files changed, 16 insertions, 6 deletions

diff --git a/src/multimedia/windows/qwindowsaudiosink.cpp b/src/multimedia/windows/qwindowsaudiosink.cpp
index 30bf054f1..f585b83e2 100644
--- a/src/multimedia/windows/qwindowsaudiosink.cpp
+++ b/src/multimedia/windows/qwindowsaudiosink.cpp
@@ -203,6 +203,9 @@ QIODevice* QWindowsAudioSink::start()
 
 bool QWindowsAudioSink::open()
 {
+    if (m_audioClient)
+        return true;
+
     HRESULT hr = m_device->Activate(__uuidof(IAudioClient), CLSCTX_INPROC_SERVER,
                             nullptr, (void**)m_audioClient.address());
     if (FAILED(hr)) {
@@ -210,6 +213,8 @@ bool QWindowsAudioSink::open()
         return false;
     }
 
+    auto resetClient = qScopeGuard([this](){ m_audioClient.reset(); });
+
     WAVEFORMATEX *pwfx = nullptr;
     hr = m_audioClient->GetMixFormat(&pwfx);
     if (FAILED(hr)) {
@@ -259,6 +264,8 @@ bool QWindowsAudioSink::open()
         return false;
     }
 
+    resetClient.dismiss();
+
     return true;
 }
 
@@ -373,12 +380,14 @@ void QWindowsAudioSink::setVolume(qreal v)
     m_volume = qBound(qreal(0), v, qreal(1));
 }
 
+void QWindowsAudioSink::stop() {
+    // TODO: investigate and find a way to drain and stop instead of closing
+    close();
+}
+
 void QWindowsAudioSink::reset()
 {
-    if (m_audioClient) {
-        m_audioClient->Stop();
-        m_audioClient->Reset();
-    }
+    close();
 }
 
 QT_END_NAMESPACE
diff --git a/src/multimedia/windows/qwindowsaudiosink_p.h b/src/multimedia/windows/qwindowsaudiosink_p.h
index 95bc05e11..1178d8ad0 100644
--- a/src/multimedia/windows/qwindowsaudiosink_p.h
+++ b/src/multimedia/windows/qwindowsaudiosink_p.h
@@ -23,6 +23,7 @@
 #include <QtCore/qdatetime.h>
 #include <QtCore/qmutex.h>
 #include <QtCore/qtimer.h>
+#include <QtCore/qpointer.h>
 
 #include <QtMultimedia/qaudio.h>
 #include <QtMultimedia/qaudiodevice.h>
@@ -48,7 +49,7 @@ public:
     QAudioFormat format() const override;
     QIODevice* start() override;
     void start(QIODevice* device) override;
-    void stop() override { close(); }
+    void stop() override;
     void reset() override;
     void suspend() override;
     void resume() override;
@@ -83,7 +84,7 @@ private:
     qreal m_volume = 1.0;
     QTimer *m_timer = nullptr;
     QScopedPointer<QIODevice> m_pushSource;
-    QIODevice *m_pullSource = nullptr;
+    QPointer<QIODevice> m_pullSource;
     QComPtr<IMMDevice> m_device;
     QComPtr<IAudioClient> m_audioClient;
     QComPtr<IAudioRenderClient> m_renderClient;