1 ------------------------------------------------------------------------------
3 -- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS --
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 --
9 -- Copyright (C) 1991-1994, Florida State University --
10 -- Copyright (C) 1995-2003, Ada Core Technologies --
12 -- GNARL is free software; you can redistribute it and/or modify it under --
13 -- terms of the GNU General Public License as published by the Free Soft- --
14 -- ware Foundation; either version 2, or (at your option) any later ver- --
15 -- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
16 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
17 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
18 -- for more details. You should have received a copy of the GNU General --
19 -- Public License distributed with GNARL; see file COPYING. If not, write --
20 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
21 -- MA 02111-1307, USA. --
23 -- As a special exception, if other files instantiate generics from this --
24 -- unit, or you link this unit with other files to produce an executable, --
25 -- this unit does not by itself cause the resulting executable to be --
26 -- covered by the GNU General Public License. This exception does not --
27 -- however invalidate any other reasons why the executable file might be --
28 -- covered by the GNU Public License. --
30 -- GNARL was developed by the GNARL team at Florida State University. --
31 -- Extensive contributions were provided by Ada Core Technologies, Inc. --
33 ------------------------------------------------------------------------------
35 -- This package provides support for the body of Ada.Task_Attributes.
37 with Ada.Finalization;
38 -- used for Limited_Controlled
40 with System.Storage_Elements;
41 -- used for Integer_Address
43 package System.Tasking.Task_Attributes is
45 type Attribute is new Integer;
46 -- A stand-in for the generic formal type of Ada.Task_Attributes
47 -- in the following declarations.
50 type Access_Node is access all Node;
51 -- This needs comments ???
54 type Access_Dummy_Wrapper is access all Dummy_Wrapper;
55 for Access_Dummy_Wrapper'Storage_Size use 0;
56 -- This is a stand-in for the generic type Wrapper defined in
57 -- Ada.Task_Attributes. The real objects allocated are always
58 -- of type Wrapper, no Dummy_Wrapper objects are ever created.
60 type Deallocator is access procedure (P : in out Access_Node);
61 -- Called to deallocate an Wrapper. P is a pointer to a Node within.
65 type Access_Instance is access all Instance;
67 type Instance is new Ada.Finalization.Limited_Controlled with record
68 Deallocate : Deallocator;
69 Initial_Value : aliased System.Storage_Elements.Integer_Address;
72 -- The index of the TCB location used by this instantiation,
73 -- if it is stored in the TCB, otherwise zero.
75 Next : Access_Instance;
76 -- Next instance in All_Attributes list.
79 procedure Finalize (X : in out Instance);
82 Wrapper : Access_Dummy_Wrapper;
83 Instance : Access_Instance;
87 -- The following type is a stand-in for the actual
88 -- wrapper type, which is different for each instantiation
89 -- of Ada.Task_Attributes.
91 type Dummy_Wrapper is record
94 Value : aliased Attribute;
95 -- The generic formal type, may be controlled
98 for Dummy_Wrapper'Alignment use Standard'Maximum_Alignment;
99 -- A number of unchecked conversions involving Dummy_Wrapper_Access
100 -- sources are performed in other units (e.g. Ada.Task_Attributes).
101 -- Ensure that the designated object is always strictly enough aligned.
103 In_Use : Direct_Index_Vector := 0;
104 -- is True for direct indices that are already used.
106 All_Attributes : Access_Instance;
107 -- A linked list of all indirectly access attributes,
108 -- which includes all those that require finalization.
110 procedure Initialize_Attributes (T : Task_ID);
111 -- Initialize all attributes created via Ada.Task_Attributes for T.
112 -- This must be called by the creator of the task, inside Create_Task,
113 -- via soft-link Initialize_Attributes_Link. On entry, abortion must
114 -- be deferred and the caller must hold no locks
116 procedure Finalize_Attributes (T : Task_ID);
117 -- Finalize all attributes created via Ada.Task_Attributes for T.
118 -- This is to be called by the task after it is marked as terminated
119 -- (and before it actually dies), inside Vulnerable_Free_Task, via the
120 -- soft-link Finalize_Attributes_Link. On entry, abortion must be deferred
121 -- and T.L must be write-locked.
123 end System.Tasking.Task_Attributes;