Various NetworkConnection improvements.

- Keep connection state.
- Store remote id
- Getter for proto_rev
- Cleanup on Stop()
- Cleaner termination of write thread.

src/NetworkConnection.cpp

@@ -20,6 +20,7 @@ NetworkConnection::NetworkConnection(std::unique_ptr<TCPStream> stream,
       m_get_entry_type(get_entry_type) {
   m_active = false;
   m_proto_rev = 0x0300;
+  m_state = static_cast<int>(kCreated);
 }
 
 NetworkConnection::~NetworkConnection() { Stop(); }
@@ -27,18 +28,38 @@ NetworkConnection::~NetworkConnection() { Stop(); }
 void NetworkConnection::Start() {
   if (m_active) return;
   m_active = true;
+  m_state = static_cast<int>(kInit);
+  // clear queues
+  while (!m_incoming.empty()) m_incoming.pop();
+  while (!m_outgoing.empty()) m_outgoing.pop();
+  // start threads
   m_write_thread = std::thread(&NetworkConnection::WriteThreadMain, this);
   m_read_thread = std::thread(&NetworkConnection::ReadThreadMain, this);
 }
 
 void NetworkConnection::Stop() {
+  m_state = static_cast<int>(kDead);
   m_active = false;
   // closing the stream so the read thread terminates
   if (m_stream) m_stream->close();
-  // send a dummy outgoing message so the write thread terminates
-  m_outgoing.push(Outgoing{Message::KeepAlive()});
+  // send an empty outgoing message set so the write thread terminates
+  m_outgoing.push(Outgoing());
+  // wait for threads to terminate
   if (m_write_thread.joinable()) m_write_thread.join();
   if (m_read_thread.joinable()) m_read_thread.join();
+  // clear queues
+  while (!m_incoming.empty()) m_incoming.pop();
+  while (!m_outgoing.empty()) m_outgoing.pop();
+}
+
+std::string NetworkConnection::remote_id() const {
+  std::lock_guard<std::mutex> lock(m_remote_id_mutex);
+  return m_remote_id;
+}
+
+void NetworkConnection::set_remote_id(StringRef remote_id) {
+  std::lock_guard<std::mutex> lock(m_remote_id_mutex);
+  m_remote_id = remote_id;
 }
 
 void NetworkConnection::ReadThreadMain() {
@@ -59,6 +80,7 @@ void NetworkConnection::ReadThreadMain() {
     m_incoming.emplace(std::move(msg));
   }
   m_incoming.emplace(nullptr);  // notify anyone waiting that we disconnected
+  m_state = static_cast<int>(kDead);
   m_active = false;
 }
 
@@ -67,7 +89,7 @@ void NetworkConnection::WriteThreadMain() {
 
   while (m_active) {
     auto msgs = m_outgoing.pop();
-    if (!m_active) break;
+    if (msgs.empty()) break;
     encoder.set_proto_rev(m_proto_rev);
     encoder.Reset();
     for (auto& msg : msgs) msg->Write(encoder);
@@ -75,5 +97,6 @@ void NetworkConnection::WriteThreadMain() {
     if (!m_stream) break;
     if (m_stream->send(encoder.data(), encoder.size(), &err) == 0) break;
   }
+  m_state = static_cast<int>(kDead);
   m_active = false;
 }