1------------------------------------------------------------------------------
2--                                                                          --
3--                 GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS                 --
4--                                                                          --
5--         S Y S T E M . T A S K I N G . T A S K _ A T T R I B U T E S      --
6--                                                                          --
7--                                  S p e c                                 --
8--                                                                          --
9--            Copyright (C) 2014-2020, Free Software Foundation, Inc.       --
10--                                                                          --
11-- GNAT is free software;  you can  redistribute it  and/or modify it under --
12-- terms of the  GNU General Public License as published  by the Free Soft- --
13-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
14-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
15-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
16-- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
17--                                                                          --
18-- As a special exception under Section 7 of GPL version 3, you are granted --
19-- additional permissions described in the GCC Runtime Library Exception,   --
20-- version 3.1, as published by the Free Software Foundation.               --
21--                                                                          --
22-- You should have received a copy of the GNU General Public License and    --
23-- a copy of the GCC Runtime Library Exception along with this program;     --
24-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
25-- <http://www.gnu.org/licenses/>.                                          --
26--                                                                          --
27-- GNARL was developed by the GNARL team at Florida State University.       --
28-- Extensive contributions were provided by Ada Core Technologies, Inc.     --
29--                                                                          --
30------------------------------------------------------------------------------
31
32--  This package provides support for the body of Ada.Task_Attributes
33
34with Ada.Unchecked_Conversion;
35
36package System.Tasking.Task_Attributes is
37
38   type Deallocator is access procedure (Ptr : Atomic_Address);
39   pragma Favor_Top_Level (Deallocator);
40
41   type Attribute_Record is record
42      Free : Deallocator;
43   end record;
44   --  The real type is declared in Ada.Task_Attributes body: Real_Attribute.
45   --  As long as the first field is the deallocator we are good.
46
47   type Attribute_Access is access all Attribute_Record;
48   pragma No_Strict_Aliasing (Attribute_Access);
49
50   function To_Attribute is new
51     Ada.Unchecked_Conversion (Atomic_Address, Attribute_Access);
52
53   function Next_Index (Require_Finalization : Boolean) return Integer;
54   --  Return the next attribute index available. Require_Finalization is True
55   --  if the attribute requires finalization and in particular its deallocator
56   --  (Free field in Attribute_Record) should be called. Raise Storage_Error
57   --  if no index is available.
58
59   function Require_Finalization (Index : Integer) return Boolean;
60   --  Return True if a given attribute index requires call to Free. This call
61   --  is not protected against concurrent access, should only be called during
62   --  finalization of the corresponding instantiation of Ada.Task_Attributes,
63   --  or during finalization of a task.
64
65   procedure Finalize (Index : Integer);
66   --  Finalize given Index, possibly allowing future reuse
67
68private
69   pragma Inline (Finalize);
70   pragma Inline (Require_Finalization);
71end System.Tasking.Task_Attributes;
72