Add validity check to TCPListener

src/network/TCPListener.cpp

@@ -62,6 +62,11 @@ namespace Feather::Network
     {
     }
 
+    bool TCPListener::IsValid() const
+    {
+        return m_socket != nullptr;
+    }
+
     void TCPListener::OnClientConnect(TCPClientHandle&& client)
     {
         m_callbacks->OnClientConnect(std::move(client));

src/network/TCPListener.h

@@ -13,6 +13,8 @@ namespace Feather::Network
         TCPListener(uint16_t port, IListenerInterface* callbacks);
         ~TCPListener();
 
+        bool IsValid() const;
+
     protected:
 
         friend class TCPClient;