112 lines
5.0 KiB
Ada
112 lines
5.0 KiB
Ada
------------------------------------------------------------------------------
|
|
-- --
|
|
-- GNAT RUN-TIME COMPONENTS --
|
|
-- --
|
|
-- A D A . S Y N C H R O N O U S _ B A R R I E R S --
|
|
-- --
|
|
-- B o d y --
|
|
-- --
|
|
-- Copyright (C) 1992-2014, Free Software Foundation, Inc. --
|
|
-- --
|
|
-- This specification is derived from the Ada Reference Manual for use with --
|
|
-- GNAT. The copyright notice above, and the license provisions that follow --
|
|
-- apply solely to the contents of the part following the private keyword. --
|
|
-- --
|
|
-- 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/>. --
|
|
-- --
|
|
-- GNAT was originally developed by the GNAT team at New York University. --
|
|
-- Extensive contributions were provided by Ada Core Technologies Inc. --
|
|
-- --
|
|
------------------------------------------------------------------------------
|
|
|
|
-- This is the body of this package using POSIX barriers
|
|
|
|
with Interfaces.C; use Interfaces.C;
|
|
|
|
package body Ada.Synchronous_Barriers is
|
|
|
|
--------------------
|
|
-- POSIX barriers --
|
|
--------------------
|
|
|
|
function pthread_barrier_init
|
|
(barrier : not null access pthread_barrier_t;
|
|
attr : System.Address := System.Null_Address;
|
|
count : unsigned) return int;
|
|
pragma Import (C, pthread_barrier_init, "pthread_barrier_init");
|
|
-- Initialize barrier with the attributes in attr. The barrier is opened
|
|
-- when count waiters arrived. If attr is null the default barrier
|
|
-- attributes are used.
|
|
|
|
function pthread_barrier_destroy
|
|
(barrier : not null access pthread_barrier_t) return int;
|
|
pragma Import (C, pthread_barrier_destroy, "pthread_barrier_destroy");
|
|
-- Destroy a previously dynamically initialized barrier
|
|
|
|
function pthread_barrier_wait
|
|
(barrier : not null access pthread_barrier_t) return int;
|
|
pragma Import (C, pthread_barrier_wait, "pthread_barrier_wait");
|
|
-- Wait on barrier
|
|
|
|
--------------
|
|
-- Finalize --
|
|
--------------
|
|
|
|
overriding procedure Finalize (Barrier : in out Synchronous_Barrier) is
|
|
Result : int;
|
|
begin
|
|
Result := pthread_barrier_destroy (Barrier.POSIX_Barrier'Access);
|
|
pragma Assert (Result = 0);
|
|
end Finalize;
|
|
|
|
overriding procedure Initialize (Barrier : in out Synchronous_Barrier) is
|
|
Result : int;
|
|
begin
|
|
Result :=
|
|
pthread_barrier_init
|
|
(barrier => Barrier.POSIX_Barrier'Access,
|
|
attr => System.Null_Address,
|
|
count => unsigned (Barrier.Release_Threshold));
|
|
pragma Assert (Result = 0);
|
|
end Initialize;
|
|
|
|
----------------------
|
|
-- Wait_For_Release --
|
|
----------------------
|
|
|
|
procedure Wait_For_Release
|
|
(The_Barrier : in out Synchronous_Barrier;
|
|
Notified : out Boolean)
|
|
is
|
|
Result : int;
|
|
|
|
PTHREAD_BARRIER_SERIAL_THREAD : constant := -1;
|
|
-- Value used to indicate the task which receives the notification for
|
|
-- the barrier open.
|
|
|
|
begin
|
|
Result :=
|
|
pthread_barrier_wait
|
|
(barrier => The_Barrier.POSIX_Barrier'Access);
|
|
pragma Assert
|
|
(Result = 0 or else Result = PTHREAD_BARRIER_SERIAL_THREAD);
|
|
|
|
Notified := (Result = PTHREAD_BARRIER_SERIAL_THREAD);
|
|
end Wait_For_Release;
|
|
|
|
end Ada.Synchronous_Barriers;
|