desklink: recycle MixerControl and correctly release media nodes.

Change-Id: Id00a7fdb3bfd995bf6891bac85d21931f527606c
Reviewed-on: https://review.haiku-os.org/c/haiku/+/2237
Reviewed-by: waddlesplash <[email protected]>
Reviewed-by: Stephan Aßmus <[email protected]>

src/bin/desklink/MediaReplicant.cpp

@@ -180,6 +180,7 @@ MediaReplicant::MediaReplicant(BRect frame, const char* name,
 		uint32 resizeMask, uint32 flags)
 	:
 	BView(frame, name, resizeMask, flags),
+	fMixerControl(NULL),
 	fVolumeSlider(NULL),
 	fMuted(false)
 {
@@ -190,6 +191,7 @@ MediaReplicant::MediaReplicant(BRect frame, const char* name,
 MediaReplicant::MediaReplicant(BMessage* message)
 	:
 	BView(message),
+	fMixerControl(NULL),
 	fVolumeSlider(NULL),
 	fMuted(false)
 {
@@ -414,12 +416,11 @@ MediaReplicant::MessageReceived(BMessage* message)
 			media_node_id mixerNodeID;
 			BMediaRoster* roster = BMediaRoster::CurrentRoster();
 			if (roster != NULL
-				&& message->FindInt32("media_node_id",&mixerNodeID) == B_OK
+				&& message->FindInt32("media_node_id", &mixerNodeID) == B_OK
 				&& roster->GetNodeFor(mixerNodeID, &mixerNode) == B_OK) {
-				if (mixerNode.kind == B_SYSTEM_MIXER) {
+				if (mixerNode.kind == B_SYSTEM_MIXER)
 					_ConnectMixer();
-					roster->ReleaseNode(mixerNode);
-				}
+				roster->ReleaseNode(mixerNode);
 			}
 			break;
 		}
@@ -595,6 +596,9 @@ MediaReplicant::_DisconnectMixer()
 
 	roster->StopWatching(this, B_MEDIA_SERVER_STARTED | B_MEDIA_NODE_CREATED);
 
+	if (fMixerControl == NULL)
+		return;
+
 	if (fMixerControl->MuteNode() != media_node::null) {
 		roster->StopWatching(this, fMixerControl->MuteNode(),
 			B_MEDIA_NEW_PARAMETER_VALUE);
@@ -624,6 +628,8 @@ MediaReplicant::_ConnectMixer()
 
 	if (errorString != NULL) {
 		SetToolTip(errorString);
+		delete fMixerControl;
+		fMixerControl = NULL;
 		return B_ERROR;
 	}
 

src/bin/desklink/MixerControl.cpp

@@ -155,7 +155,7 @@ MixerControl::Connect(int32 volumeWhich, float* _value, const char** _error)
 		errorString = "Media services not running";
 
 	if (status != B_OK) {
-		fGainMediaNode = media_node::null;
+		_Disconnect();
 		fMuteMediaNode = media_node::null;
 	}