check if session is terminated before send

libi2pd_client/I2CP.cpp

@@ -806,6 +806,9 @@ namespace client
 	void I2CPSession::SendMessagePayloadMessage (const uint8_t * payload, size_t len)
 	{
 		// we don't use SendI2CPMessage to eliminate additional copy
+		auto socket = m_Socket;
+		if (socket)
+		{
 			auto l = len + 10 + I2CP_HEADER_SIZE;
 			uint8_t * buf = new uint8_t[l];
 			htobe32buf (buf + I2CP_HEADER_LENGTH_OFFSET, len + 10);
@@ -814,10 +817,13 @@ namespace client
 			htobe32buf (buf + I2CP_HEADER_SIZE + 2, m_MessageID++);
 			htobe32buf (buf + I2CP_HEADER_SIZE + 6, len);
 			memcpy (buf + I2CP_HEADER_SIZE + 10, payload, len);
-		boost::asio::async_write (*m_Socket, boost::asio::buffer (buf, l), boost::asio::transfer_all (),
+			boost::asio::async_write (*socket, boost::asio::buffer (buf, l), boost::asio::transfer_all (),
 			std::bind(&I2CPSession::HandleI2CPMessageSent, shared_from_this (),
 				std::placeholders::_1, std::placeholders::_2, buf));
 		}	
+		else
+			LogPrint (eLogError, "I2CP: Can't write to the socket");
+	}
 
 	I2CPServer::I2CPServer (const std::string& interface, int port, bool isSingleThread):
 		RunnableService ("I2CP"), m_IsSingleThread (isSingleThread),