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------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS --
-- --
-- A D A . C A L E N D A R . D E L A Y S --
-- --
-- B o d y --
-- --
-- Copyright (C) 1991-2017, Florida State University --
-- Copyright (C) 1995-2021, AdaCore --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. --
-- --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception, --
-- version 3.1, as published by the Free Software Foundation. --
-- --
-- You should have received a copy of the GNU General Public License and --
-- a copy of the GCC Runtime Library Exception along with this program; --
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
-- <http://www.gnu.org/licenses/>. --
-- --
-- GNARL was developed by the GNARL team at Florida State University. --
-- Extensive contributions were provided by Ada Core Technologies, Inc. --
-- --
------------------------------------------------------------------------------
with System.OS_Primitives;
with System.Soft_Links;
package body Ada.Calendar.Delays is
package OSP renames System.OS_Primitives;
package SSL renames System.Soft_Links;
use type SSL.Timed_Delay_Call;
-- Earlier, System.Time_Operations was used to implement the following
-- operations. The idea was to avoid sucking in the tasking packages. This
-- did not work. Logically, we can't have it both ways. There is no way to
-- implement time delays that will have correct task semantics without
-- reference to the tasking run-time system. To achieve this goal, we now
-- use soft links.
-----------------------
-- Local Subprograms --
-----------------------
procedure Timed_Delay_NT (Time : Duration; Mode : Integer);
-- Timed delay procedure used when no tasking is active
---------------
-- Delay_For --
---------------
procedure Delay_For (D : Duration) is
begin
SSL.Timed_Delay.all (Duration'Min (D, OSP.Max_Sensible_Delay),
OSP.Relative);
end Delay_For;
-----------------
-- Delay_Until --
-----------------
procedure Delay_Until (T : Time) is
D : constant Duration := To_Duration (T);
begin
SSL.Timed_Delay.all (D, OSP.Absolute_Calendar);
end Delay_Until;
--------------------
-- Timed_Delay_NT --
--------------------
procedure Timed_Delay_NT (Time : Duration; Mode : Integer) is
begin
OSP.Timed_Delay (Time, Mode);
end Timed_Delay_NT;
-----------------
-- To_Duration --
-----------------
function To_Duration (T : Time) return Duration is
begin
-- Since time has multiple representations on different platforms, a
-- target independent operation in Ada.Calendar is used to perform
-- this conversion.
return Delay_Operations.To_Duration (T);
end To_Duration;
begin
-- Set up the Timed_Delay soft link to the non tasking version if it has
-- not been already set. If tasking is present, Timed_Delay has already set
-- this soft link, or this will be overridden during the elaboration of
-- System.Tasking.Initialization
pragma Annotate (CodePeer, Modified, SSL.Timed_Delay);
if SSL.Timed_Delay = null then
SSL.Timed_Delay := Timed_Delay_NT'Access;
end if;
end Ada.Calendar.Delays;