AVFoundation: fix mediaStatus and state changes

When both state and mediaStatus are updated at the same time, make sure
both variables are updated before emitting the corresponding signals.
Also, always emit mediaStatusChanged() signals before stateChanged() to
make sure mediaStatus changes are not cancelled by some action
resulting from a state change.

Task-number: QTBUG-49578
Change-Id: I0caea8261120595227834dbac7fed286d125bcab
Reviewed-by: Christian Stromme <christian.stromme@qt.io>

1 files changed, 15 insertions, 6 deletions

diff --git a/src/plugins/avfoundation/mediaplayer/avfmediaplayersession.mm b/src/plugins/avfoundation/mediaplayer/avfmediaplayersession.mm
index 53cdebd82..d3ec2ff9c 100644
--- a/src/plugins/avfoundation/mediaplayer/avfmediaplayersession.mm
+++ b/src/plugins/avfoundation/mediaplayer/avfmediaplayersession.mm
@@ -458,15 +458,19 @@ void AVFMediaPlayerSession::setMedia(const QMediaContent &content, QIODevice *st
     m_requestedPosition = -1;
     Q_EMIT positionChanged(position());
 
-    QMediaPlayer::MediaStatus oldMediaStatus = m_mediaStatus;
+    const QMediaPlayer::MediaStatus oldMediaStatus = m_mediaStatus;
+    const QMediaPlayer::State oldState = m_state;
 
     if (content.isNull() || content.canonicalUrl().isEmpty()) {
         m_mediaStatus = QMediaPlayer::NoMedia;
-        if (m_state != QMediaPlayer::StoppedState)
-            Q_EMIT stateChanged(m_state = QMediaPlayer::StoppedState);
+        m_state = QMediaPlayer::StoppedState;
 
         if (m_mediaStatus != oldMediaStatus)
             Q_EMIT mediaStatusChanged(m_mediaStatus);
+
+        if (m_state != oldState)
+            Q_EMIT stateChanged(m_state);
+
         return;
     } else {
 
@@ -777,14 +781,15 @@ void AVFMediaPlayerSession::processEOS()
 #endif
     Q_EMIT positionChanged(position());
     m_mediaStatus = QMediaPlayer::EndOfMedia;
+    m_state = QMediaPlayer::StoppedState;
 
     // At this point, frames should not be rendered anymore.
     // Clear the output layer to make sure of that.
     if (m_videoOutput)
         m_videoOutput->setLayer(0);
 
-    Q_EMIT stateChanged(m_state = QMediaPlayer::StoppedState);
     Q_EMIT mediaStatusChanged(m_mediaStatus);
+    Q_EMIT stateChanged(m_state);
 }
 
 void AVFMediaPlayerSession::processLoadStateChange()
@@ -864,7 +869,11 @@ void AVFMediaPlayerSession::processMediaLoadError()
         m_requestedPosition = -1;
         Q_EMIT positionChanged(position());
     }
+
+    m_mediaStatus = QMediaPlayer::InvalidMedia;
+    m_state = QMediaPlayer::StoppedState;
+
     Q_EMIT error(QMediaPlayer::FormatError, tr("Failed to load media"));
-    Q_EMIT mediaStatusChanged(m_mediaStatus = QMediaPlayer::InvalidMedia);
-    Q_EMIT stateChanged(m_state = QMediaPlayer::StoppedState);
+    Q_EMIT mediaStatusChanged(m_mediaStatus);
+    Q_EMIT stateChanged(m_state);
 }