------------------------------------------------------------------------------
-- --
-- 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 --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2022, 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 spec of this package using POSIX barriers
with System;
private with Ada.Finalization;
private with Interfaces.C;
package Ada.Synchronous_Barriers with SPARK_Mode => Off is
pragma Preelaborate (Synchronous_Barriers);
subtype Barrier_Limit is Positive range 1 .. Positive'Last;
type Synchronous_Barrier (Release_Threshold : Barrier_Limit) is
limited private;
procedure Wait_For_Release
(The_Barrier : in out Synchronous_Barrier;
Notified : out Boolean);
private
-- POSIX barrier data type
SIZEOF_PTHREAD_BARRIER_T : constant :=
(if System.Word_Size = 64 then 32 else 20);
-- Value defined according to the linux definition in pthreadtypes.h. On
-- other system, e.g. MIPS IRIX, the object is smaller, so it works
-- correctly although we are wasting some space.
type pthread_barrier_t_view is (size_based, align_based);
type pthread_barrier_t (Kind : pthread_barrier_t_view := size_based) is
record
case Kind is
when size_based =>
size : Interfaces.C.char_array (1 .. SIZEOF_PTHREAD_BARRIER_T);
when align_based =>
align : Interfaces.C.long;
end case;
end record;
pragma Unchecked_Union (pthread_barrier_t);
type Synchronous_Barrier (Release_Threshold : Barrier_Limit) is
new Ada.Finalization.Limited_Controlled with
record
POSIX_Barrier : aliased pthread_barrier_t;
end record;
overriding procedure Initialize (Barrier : in out Synchronous_Barrier);
overriding procedure Finalize (Barrier : in out Synchronous_Barrier);
end Ada.Synchronous_Barriers;