1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT RUN-TIME COMPONENTS                         --
4--                                                                          --
5--          A D A . R E A L _ T I M E . T I M I N G _ E V E N T S           --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--           Copyright (C) 2005-2019, Free Software Foundation, Inc.        --
10--                                                                          --
11-- This specification is derived from the Ada Reference Manual for use with --
12-- GNAT. The copyright notice above, and the license provisions that follow --
13-- apply solely to the  contents of the part following the private keyword. --
14--                                                                          --
15-- GNAT is free software;  you can  redistribute it  and/or modify it under --
16-- terms of the  GNU General Public License as published  by the Free Soft- --
17-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
18-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
19-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
20-- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
21--                                                                          --
22-- As a special exception under Section 7 of GPL version 3, you are granted --
23-- additional permissions described in the GCC Runtime Library Exception,   --
24-- version 3.1, as published by the Free Software Foundation.               --
25--                                                                          --
26-- You should have received a copy of the GNU General Public License and    --
27-- a copy of the GCC Runtime Library Exception along with this program;     --
28-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
29-- <http://www.gnu.org/licenses/>.                                          --
30--                                                                          --
31-- GNAT was originally developed  by the GNAT team at  New York University. --
32-- Extensive contributions were provided by Ada Core Technologies Inc.      --
33--                                                                          --
34------------------------------------------------------------------------------
35
36with Ada.Finalization;
37
38package Ada.Real_Time.Timing_Events is
39
40   type Timing_Event is tagged limited private;
41
42   type Timing_Event_Handler
43     is access protected procedure (Event : in out Timing_Event);
44
45   procedure Set_Handler
46     (Event   : in out Timing_Event;
47      At_Time : Time;
48      Handler : Timing_Event_Handler);
49
50   procedure Set_Handler
51     (Event   : in out Timing_Event;
52      In_Time : Time_Span;
53      Handler : Timing_Event_Handler);
54
55   function Current_Handler
56     (Event : Timing_Event) return Timing_Event_Handler;
57
58   procedure Cancel_Handler
59     (Event     : in out Timing_Event;
60      Cancelled : out Boolean);
61
62   function Time_Of_Event (Event : Timing_Event) return Time;
63
64private
65
66   type Timing_Event is new Ada.Finalization.Limited_Controlled with record
67      Timeout : Time := Time_First;
68      --  The time at which the user's handler should be invoked when the
69      --  event is "set" (i.e., when Handler is not null).
70
71      Handler : Timing_Event_Handler;
72      --  An access value designating the protected procedure to be invoked
73      --  at the Timeout time in the future.  When this value is null the event
74      --  is said to be "cleared" and no timeout is processed.
75   end record;
76
77   overriding procedure Finalize (This : in out Timing_Event);
78   --  Finalization procedure is required to satisfy (RM D.15 (19/2)), which
79   --  says that the object must be cleared on finalization.
80
81end Ada.Real_Time.Timing_Events;
82