Fixed client ejections causing segfaults

src/clientagent/client_participant.cpp

@@ -52,7 +52,8 @@ ClientParticipant::ClientParticipant(
 }
 
 ClientParticipant::~ClientParticipant() {
-  NetworkClient::Shutdown();
+  // Call shutdown just in-case (most likely redundant.)
+  Shutdown();
 
   _clientAgent->ParticipantLeft();
 }
@@ -61,6 +62,13 @@ ClientParticipant::~ClientParticipant() {
  * Manually disconnect and delete this client participant.
  */
 void ClientParticipant::Shutdown() {
+  if (_disconnected) {
+    return;
+  }
+
+  // Kill the network connection.
+  NetworkClient::Shutdown();
+
   // Stop the heartbeat timer (if we have one.)
   if (_heartbeatTimer) {
     _heartbeatTimer->stop();

src/messagedirector/md_participant.cpp

@@ -17,14 +17,24 @@ MDParticipant::MDParticipant(const std::shared_ptr<uvw::tcp_handle> &socket)
 }
 
 MDParticipant::~MDParticipant() {
-  NetworkClient::Shutdown();
+  // Call shutdown just in-case (most likely redundant.)
+  Shutdown();
+
   MessageDirector::Instance()->ParticipantLeft();
 }
 
 /**
  * Manually disconnect and delete this MD participant.
  */
 void MDParticipant::Shutdown() {
+  if (_disconnected) {
+    return;
+  }
+
+  // Kill the network connection.
+  NetworkClient::Shutdown();
+
+  // Unsubscribe from all channels so post removes aren't accidently routed to us.
   ChannelSubscriber::Shutdown();
 
   Logger::Verbose(std::format("[MD] Routing {} post-remove(s) for '{}'",

src/messagedirector/md_participant.h

@@ -11,10 +11,10 @@
 
 namespace Ardos {
 
-class MDParticipant : public NetworkClient, public ChannelSubscriber {
+class MDParticipant final : public NetworkClient, public ChannelSubscriber {
 public:
   explicit MDParticipant(const std::shared_ptr<uvw::tcp_handle> &socket);
-  ~MDParticipant();
+  ~MDParticipant() override;
 
 private:
   void Shutdown() override;

src/net/network_client.cpp

@@ -35,9 +35,10 @@ NetworkClient::NetworkClient(const std::shared_ptr<uvw::tcp_handle> &socket)
 
   _socket->on<uvw::write_event>(
       [this](const uvw::write_event &event, uvw::tcp_handle &) {
-        if (_disconnected && _socket != nullptr) {
+        if (_disconnected && !_socketClosed) {
           _socket->close();
-          _socket.reset();
+
+          _socketClosed = true;
         }
 
         _isWriting = false;
@@ -61,15 +62,16 @@ bool NetworkClient::Disconnected() const { return _disconnected; }
 uvw::socket_address NetworkClient::GetRemoteAddress() { return _remoteAddress; }
 
 void NetworkClient::Shutdown() {
-  if (_socket == nullptr) {
+  if (_disconnected) {
     return;
   }
 
   _disconnected = true;
 
-  if (!_isWriting) {
+  if (!_isWriting && !_socketClosed) {
     _socket->close();
-    _socket.reset();
+
+    _socketClosed = true;
   }
 }
 
@@ -79,7 +81,7 @@ void NetworkClient::HandleClose(uv_errno_t code) {
     return;
   }
 
-  _disconnected = true;
+  _socketClosed = true;
 
   HandleDisconnect(code);
 }
@@ -139,14 +141,14 @@ void NetworkClient::SendDatagram(const std::shared_ptr<Datagram> &dg) {
     return;
   }
 
-  size_t sendSize = sizeof(uint16_t) + dg->Size();
+  const size_t sendSize = sizeof(uint16_t) + dg->Size();
   auto sendBuffer = std::unique_ptr<char[]>(new char[sendSize]);
 
-  uint16_t dgSize = dg->Size();
+  const uint16_t dgSize = dg->Size();
 
-  auto sendPtr = &sendBuffer.get()[0];
+  const auto sendPtr = &sendBuffer.get()[0];
   // Datagram size tag.
-  memcpy(sendPtr, (char *)&dgSize, sizeof(uint16_t));
+  memcpy(sendPtr, &dgSize, sizeof(uint16_t));
   // Datagram data.
   memcpy(sendPtr + sizeof(uint16_t), dg->GetData(), dg->Size());
 

src/net/network_client.h

@@ -25,6 +25,8 @@ class NetworkClient {
   virtual void HandleClientDatagram(const std::shared_ptr<Datagram> &dg) = 0;
   void SendDatagram(const std::shared_ptr<Datagram> &dg);
 
+  bool _disconnected = false;
+
 private:
   void HandleClose(uv_errno_t code);
   void HandleData(const std::unique_ptr<char[]> &data, size_t size);
@@ -33,8 +35,9 @@ class NetworkClient {
   std::shared_ptr<uvw::tcp_handle> _socket;
   uvw::socket_address _remoteAddress;
   std::vector<uint8_t> _data_buf;
-  bool _disconnected = false;
+
   bool _isWriting = false;
+  bool _socketClosed = false;
 };
 
 } // namespace Ardos