worker: Add Transport::Destroying() protected method (#1114)

CHANGELOG.md

@@ -1,6 +1,11 @@
 # Changelog
 
 
+### Next
+
+* `Worker`: Add `Transport::Destroying()` protected method ([PR #1114](https://github.com/versatica/mediasoup/pull/1114)).
+
+
 ### 3.12.5
 
 * `DataConsumer`: Fix removed 'bufferedamountlow' notification ([PR #1113](https://github.com/versatica/mediasoup/pull/1113)).

worker/include/RTC/Transport.hpp

@@ -144,6 +144,7 @@ namespace RTC
 
 	protected:
 		// Must be called from the subclass.
+		void Destroying();
 		void Connected();
 		void Disconnected();
 		void DataReceived(size_t len)

worker/src/RTC/DirectTransport.cpp

@@ -28,6 +28,10 @@ namespace RTC
 	{
 		MS_TRACE();
 
+		// Tell the Transport parent class that we are about to destroy
+		// the class instance.
+		Destroying();
+
 		this->shared->channelMessageRegistrator->UnregisterHandler(this->id);
 	}
 

worker/src/RTC/PipeTransport.cpp

@@ -117,6 +117,10 @@ namespace RTC
 	{
 		MS_TRACE();
 
+		// Tell the Transport parent class that we are about to destroy
+		// the class instance.
+		Destroying();
+
 		this->shared->channelMessageRegistrator->UnregisterHandler(this->id);
 
 		delete this->udpSocket;

worker/src/RTC/PlainTransport.cpp

@@ -206,6 +206,10 @@ namespace RTC
 	{
 		MS_TRACE();
 
+		// Tell the Transport parent class that we are about to destroy
+		// the class instance.
+		Destroying();
+
 		this->shared->channelMessageRegistrator->UnregisterHandler(this->id);
 
 		delete this->udpSocket;

worker/src/RTC/Transport.cpp

@@ -182,9 +182,6 @@ namespace RTC
 	{
 		MS_TRACE();
 
-		// Set the destroying flag.
-		this->destroying = true;
-
 		// The destructor must delete and clear everything silently.
 
 		// Delete all Producers.
@@ -1594,6 +1591,13 @@ namespace RTC
 		}
 	}
 
+	void Transport::Destroying()
+	{
+		MS_TRACE();
+
+		this->destroying = true;
+	}
+
 	void Transport::Connected()
 	{
 		MS_TRACE();

worker/src/RTC/WebRtcTransport.cpp

@@ -300,6 +300,11 @@ namespace RTC
 	{
 		MS_TRACE();
 
+		// We need to tell the Transport parent class that we are about to destroy
+		// the class instance. This is because child's destructor runs before
+		// parent's destructor. See comment in Transport::OnSctpAssociationSendData().
+		Destroying();
+
 		this->shared->channelMessageRegistrator->UnregisterHandler(this->id);
 
 		// Must delete the DTLS transport first since it will generate a DTLS alert