Send the reason of the connection close to the user

src/irc/irc_client.cpp

@@ -93,9 +93,11 @@ void IrcClient::on_connected()
   this->send_pending_data();
 }
 
-void IrcClient::on_connection_close()
+void IrcClient::on_connection_close(const std::string& error_msg)
 {
-  static const std::string message = "Connection closed by remote server.";
+  std::string message = "Connection closed by remote server.";
+  if (!error_msg.empty())
+    message += ": " + error_msg;
   const IrcMessage error{"ERROR", {message}};
   this->on_error(error);
   log_warning(message);

src/irc/irc_client.hpp

@@ -41,7 +41,7 @@ public:
   /**
    * Close the connection, remove us from the poller
    */
-  void on_connection_close() override final;
+  void on_connection_close(const std::string& error) override final;
   /**
    * Parse the data we have received so far and try to get one or more
    * complete messages from it.

src/network/tcp_socket_handler.cpp

@@ -207,22 +207,17 @@ ssize_t TCPSocketHandler::do_recv(void* recv_buf, const size_t buf_size)
   ssize_t size = ::recv(this->socket, recv_buf, buf_size, 0);
   if (0 == size)
     {
-      this->on_connection_close();
+      this->on_connection_close("");
       this->close();
     }
   else if (-1 == size)
     {
       log_warning("Error while reading from socket: " << strerror(errno));
+      this->close();
       if (this->connecting)
-        {
-          this->close();
         this->on_connection_failed(strerror(errno));
-        }
       else
-        {
-          this->close();
-          this->on_connection_close();
-        }
+        this->on_connection_close(strerror(errno));
     }
   return size;
 }
@@ -245,7 +240,7 @@ void TCPSocketHandler::on_send()
   if (res < 0)
     {
       log_error("sendmsg failed: " << strerror(errno));
-      this->on_connection_close();
+      this->on_connection_close(strerror(errno));
       this->close();
     }
   else

src/network/tcp_socket_handler.hpp

@@ -96,7 +96,7 @@ public:
   /**
    * Called when we detect a disconnection from the remote host.
    */
-  virtual void on_connection_close() = 0;
+  virtual void on_connection_close(const std::string& error) = 0;
   /**
    * Handle/consume (some of) the data received so far.  The data to handle
    * may be in the in_buf buffer, or somewhere else, depending on what

src/xmpp/xmpp_component.cpp

@@ -108,10 +108,17 @@ void XmppComponent::on_connected()
   this->send_pending_data();
 }
 
-void XmppComponent::on_connection_close()
+void XmppComponent::on_connection_close(const std::string& error)
+{
+  if (error.empty())
     {
       log_info("XMPP server closed connection");
     }
+  else
+    {
+      log_info("XMPP server closed connection: " << error);
+    }
+}
 
 void XmppComponent::parse_in_buffer(const size_t size)
 {

src/xmpp/xmpp_component.hpp

@@ -38,7 +38,7 @@ public:
 
   void on_connection_failed(const std::string& reason) override final;
   void on_connected() override final;
-  void on_connection_close() override final;
+  void on_connection_close(const std::string& error) override final;
   void parse_in_buffer(const size_t size) override final;
 
   /**