Re: Using GSocket in a GTK application

[Jacques Pelletier <jpelletier ieee org>]

On Sunday 13 February 2011 22:17:12 Jacques Pelletier wrote:
> Hi all,
>
> I'm using GSocket in a GTK application in non-blocking mode.
>
> Once the connection is done, I'm creating a source for the main event loop:
>       my_source = g_socket_create_source(my_socket, my_events, NULL);
>
> How do we specify a callback? Should I use g_source_set_callback ()?
> The callback would handle the input side from the host to my application.

I've been able to work this out. Here is how I implemented the client side:

...
          /* Connect asynchronously */
      mySocketClient = g_socket_client_new();

      g_socket_client_connect_to_host_async(
        mySocketClient,
        myUrl,
        myPort,
        NULL,
        my_client_connect_async_function,
        NULL);
...


void my_client_connect_async_function(GObject *source_object,
                          GAsyncResult *res,
                          gpointer user_data)
{
  mySocketConnection = 
g_socket_client_connect_to_host_finish(source_object,res,NULL);

  if (mySocketConnection != NULL)
    {
      mySocket = g_socket_connection_get_socket(mySocketConnection);
      mySource = g_socket_create_source(mySocket,
                                                                        G_IO_IN | G_IO_PRI | G_IO_NVAL,
                                                                        NULL);
      g_source_set_callback(mySource, myCallback,NULL,NULL);
      mySource_id = g_source_attach(mySource,NULL);

        /* Instructions for updating the GUI */
    }
  else
  {
        /* Socket connection failed */
  }
}

/* Process incoming data from socket */
gboolean myCallback(GSocket *source, GIOCondition condition, gpointer data)
{
  int Input_Length;
  gchar Receive_Buffer[1024];

  switch (condition)
        {
          /* Check for socket error */
        case (G_IO_ERR | G_IO_HUP):
        case G_IO_HUP:
      g_message("Socket error HUP\n");
          PortClose();
      goto error;

        case (G_IO_ERR | G_IO_NVAL):
        case (G_IO_NVAL):
      g_message("Socket error NVAL\n");
      goto error;

          /* Check for data to be read (or if the socket was closed) */
        case G_IO_IN:
          Input_Length = g_socket_receive(source, (gchar 
*)Receive_Buffer,1024,NULL,NULL);
          if (Input_Length != -1)
                {
                        /* Update GUI according to the received data */           
                        MyGuiUpdate(Receive_Buffer,Input_Length);
                }
          break;

        default:
          ;
        } /* condition */

  /* Returns TRUE so it remains installed until we remove it */
  return TRUE;

 error:
  return FALSE;
}

void SocketClose(void)
{
  g_socket_close(mySocket,NULL);
  g_object_unref(mySocketConnection);
  g_object_unref(mySocketClient);
  g_source_unref(mySource);
}


Any comments about how to improve, missing code, etc.?

I'm now working on the server side and post the result here for convenience.

Thanks,

JP