File : asl-semaphore-counting.adb
-- The Ada Structured Library - A set of container classes and general
-- tools for use with Ada95.
-- Copyright (C) 1998-1999 Corey Minyard (minyard@acm.org)
--
-- This library 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 library 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
--
-- As a special exception, if other files instantiate generics from this
-- unit, or you link this unit with other files to produce an executable,
-- this unit does not by itself cause the resulting executable to be
-- covered by the GNU General Public License. This exception does not
-- however invalidate any other reasons why the executable file might be
-- covered by the GNU Public License.
--
package body Asl.Semaphore.Counting is
------------------------------------------------------------------------
procedure Take (O : in out Object) is
begin
O.The_Mutex.Wait;
end Take;
------------------------------------------------------------------------
procedure Give (O : in out Object) is
begin
O.The_Mutex.Release;
end Give;
------------------------------------------------------------------------
procedure Try_To_Take (O : in out Object;
Success : out Boolean;
Timeout : in Duration := 0.0) is
begin
select
O.The_Mutex.Wait;
Success := True;
or
delay Timeout;
Success := False;
end select;
end Try_To_Take;
------------------------------------------------------------------------
------------------------------------------------------------------------
protected body Mutex is
---------------------------------------------------------------------
entry Wait when (Count > 0) is
begin
Count := Count - 1;
end Wait;
---------------------------------------------------------------------
procedure Release is
begin
Count := Count + 1;
end Release;
end Mutex;
end Asl.Semaphore.Counting;