File : adagio-connect-peer_manager.adb


------------------------------------------------------------------------------

--                         ADAGIO - ADALID - AENEA.                         --

--                                                                          --

--                            Copyright (C) 2003                            --

--                                 A. Mosteo.                               --

--                                                                          --

--  Authors: A. Mosteo. (adagio@mosteo.com)                                 --

--                                                                          --

--  If you have any questions in regard to this software, please address    --

--  them to the above email.                                                --

--                                                                          --

--  This program is free software; you can redistribute it and/or modify    --

--  it under the terms of the GNU General Public License as published by    --

--  the Free Software Foundation; either version 2 of the License, or (at   --

--  your option) any later version.                                         --

--                                                                          --

--  This program is distributed in the hope that it will be useful, but     --

--  WITHOUT ANY WARRANTY; without even the implied warranty of              --

--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU       --

--  General Public License for more details.                                --

--                                                                          --

--  You should have received a copy of the GNU General Public License       --

--  along with this library; if not, write to the Free Software Foundation, --

--  Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.          --

--                                                                          --

--  You are not allowed to use any part of this code to develop a program   --

--  whose output would be used to harass or prosecute other users of the    --

--  networks Adagio connects with. All data collected with Adagio or a tool --

--  containing Adagio code about other network users must remain            --

--  confidential and cannot be made public by any mean, nor be used to      --

--  harass or legally prosecute these users.                                --

------------------------------------------------------------------------------

--  $Id: adagio-connect-peer_manager.adb,v 1.3 2004/01/21 21:05:36 Jano Exp $


--  For general purpose connections, like chats, browses, etc.


with Adagio.Statistics;
with Adagio.Statistics.Integers;
with Adagio.Trace;
with Generic_event_queue;

with Ada.Calendar;
with Ada.Real_time;
use  Ada;

package body Adagio.Connect.Peer_manager is

   Stat_peers : constant String := "Misc - Chat/browse peers";

   use type Slot_list.Iterator_type;

   ------------------------------------------------------------------------

   -- Event system                                                       --

   ------------------------------------------------------------------------

   procedure Process_event (Id : in String) is
   begin
      Object.Process (Id);
   end Process_event;

   package Event_queue is new Generic_event_queue (
      String, Process_event, 1024 * 1024);

   Events : Event_queue.Object;

   procedure Create_event (Id : in String; Sleep : in Duration) is
      Event : Event_queue.Event_type;
      use Real_time;
   begin
      Event_queue.Create (
         Events, Event, 
         Real_time.Clock + To_time_span (Sleep), Id);
   end Create_event;

   ------------------------------------------------------------------------

   -- Object                                                             --

   ------------------------------------------------------------------------

   protected body Object is

      ---------

      -- Add --

      ---------

      -- Enqueue a peer for management.

      procedure Add (This : access Peer.Object'Class) is
      begin
         if Slot_list.Find (Peers, Peer.Id (This.all)) /= 
            Slot_list.Back (Peers)
         then
            raise Already_connected;
         end if;

         -- Enqueue and first process.

         Slot_list.Insert (
            Peers, Peer.Id (This.all), (Peer => Peer.Object_access (This)));
         Process (Peer.Id (This.all));
      end Add;

      -------------

      -- Process --

      -------------

      -- Do the processing for a given Id (backcalled from timeout queue).

      procedure Process (Id : in String) is 
         use Calendar;
         use Slot_list;
         I : Iterator_type := Find (Peers, Id);
         C : Peer.Context_type;
         P : Peer.Object_access;
      begin
         if I = Back (Peers) then
            Trace.Log ("Peer_manager.Process: Received event for missing " &
               "peer: " & Id, Trace.Warning);
         else
            begin
               P := Element (I).Peer;
               Peer.Process (P.all, C);
            exception
               when E : others =>
                  Trace.Log ("Peer_manager.Process [dispatched process]: " &
                     Trace.Report (E), Trace.Error);
               Trace.Log ("Peer connection with " & Id & " dropped.");
               Peer.Free (P);
               Delete (Peers, Id);
               Statistics.Object.Set (
                  Stat_peers,
                  Statistics.Integers.Create (Length (Peers)));
               return;
            end;
            -- Finished?

            if C.Is_done then
               Trace.Log ("Peer connection with " & Id & " finished.");
               Peer.Free (P);
               Delete (Peers, Id);
            elsif C.Sleep < 0.1 then
               Create_event (Id, 0.1);
            else
               Create_event (id, C.Sleep);
            end if;
         end if;

         -- Stats

         Statistics.Object.Set (
            Stat_peers,
            Statistics.Integers.Create (Length (Peers)));
      end Process;

   end Object;

   ------------------------------------------------------------------------

   -- Shutdown                                                           --

   ------------------------------------------------------------------------

   procedure Shutdown is
   begin
      Event_queue.Shutdown (Events);
   end Shutdown;

begin
   -- Initial stats

   Statistics.Object.Set (
      Stat_peers,
      Statistics.Integers.Create (0));
end Adagio.Connect.Peer_manager;