File : agpl-event_queues-calendar.ads
------------------------------------------------------------------------------
-- 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: event_queue.ads,v 1.6 2004/01/29 21:47:09 Jano Exp $
-- Efficient event queue. Useful for timeouts, as an example.
-- Implemented with tagged types. That makes genericity unnecesary. A queue
-- can perform multiple kind of events.
with Agpl.Protected_sorted_index;
with Agpl.Sequence;
with Ada.Calendar;
use Ada.Calendar;
package Agpl.Event_queues.Calendar is
-- Handle for an event. Can be used to cancel it:
type Event_type is private;
-- Get time of an event:
function Get_Deadline (Event : in Event_Type) return Ada.Calendar.Time;
type Object (Stack_size : Natural := 64 * 1024) is limited private;
type Object_access is access all Object;
-- Create an event
procedure Create (
This : in out Object;
Event : out Event_type;
Deadline : in Time;
Action : in Action_procedure;
Context : in Context_type'Class);
procedure Cancel (
This : in out Object;
Event : in out Event_type);
-- Pending events?
function Is_empty (This : in Object) return Boolean;
function Length (This : in Object) return Natural;
procedure Shutdown (This : in out Object);
private
-- Uses timestamp
function Less (L, R : in Event_type) return Boolean;
-- Uses Id.
function Equal (L, R : in Event_type) return Boolean;
pragma Inline (Less, Equal);
-- Maximum simultaneous pending events:
type Id_type is mod 2 ** 32;
package Id_sequence is new Sequence (Id_type);
type Event_type is record
Deadline : Time;
Id : Id_type;
Action : Action_procedure;
Context : Context_access;
end record;
package Event_list is new
Protected_sorted_index (Event_type, Less, Equal);
type Action_type is (New_event, Job_finished);
task type Active_object (Parent : access Object) is
entry Reschedule (Action : in Action_type);
entry Shutdown;
end Active_object;
task type Worker (Parent : access Object) is
pragma Storage_size (Parent.Stack_size);
entry Execute (Event : in Event_type);
end Worker;
type Object (Stack_size : Natural := 64 * 1024) is record
List : Event_list.Sorted_index;
Seq : Id_sequence.Object;
Waiter : Active_object (Object'Access);
Doer : Worker (Object'Access);
end record;
end Agpl.Event_queues.Calendar;