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) 1991-1994, Florida State University -- 10-- Copyright (C) 1995-2010, AdaCore -- 11-- -- 12-- GNAT 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 3, or (at your option) any later ver- -- 15-- sion. GNAT 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. -- 18-- -- 19-- As a special exception under Section 7 of GPL version 3, you are granted -- 20-- additional permissions described in the GCC Runtime Library Exception, -- 21-- version 3.1, as published by the Free Software Foundation. -- 22-- -- 23-- You should have received a copy of the GNU General Public License and -- 24-- a copy of the GCC Runtime Library Exception along with this program; -- 25-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- 26-- <http://www.gnu.org/licenses/>. -- 27-- -- 28-- GNARL was developed by the GNARL team at Florida State University. -- 29-- Extensive contributions were provided by Ada Core Technologies, Inc. -- 30-- -- 31------------------------------------------------------------------------------ 32 33-- This package provides support for the body of Ada.Task_Attributes 34 35with Ada.Finalization; 36 37with System.Storage_Elements; 38 39package System.Tasking.Task_Attributes is 40 41 type Attribute is new Integer; 42 -- A stand-in for the generic formal type of Ada.Task_Attributes 43 -- in the following declarations. 44 45 type Node; 46 type Access_Node is access all Node; 47 -- This needs comments ??? 48 49 function To_Access_Node is new Ada.Unchecked_Conversion 50 (Access_Address, Access_Node); 51 -- Used to fetch pointer to indirect attribute list. Declaration is in 52 -- spec to avoid any problems with aliasing assumptions. 53 54 type Dummy_Wrapper; 55 type Access_Dummy_Wrapper is access all Dummy_Wrapper; 56 pragma No_Strict_Aliasing (Access_Dummy_Wrapper); 57 -- Needed to avoid possible incorrect aliasing situations from 58 -- instantiation of Unchecked_Conversion in body of Ada.Task_Attributes. 59 60 for Access_Dummy_Wrapper'Storage_Size use 0; 61 -- Access_Dummy_Wrapper is a stand-in for the generic type Wrapper defined 62 -- in Ada.Task_Attributes. The real objects allocated are always 63 -- of type Wrapper, no Dummy_Wrapper objects are ever created. 64 65 type Deallocator is access procedure (P : in out Access_Node); 66 -- Called to deallocate an Wrapper. P is a pointer to a Node within 67 68 type Instance; 69 70 type Access_Instance is access all Instance; 71 72 type Instance is new Ada.Finalization.Limited_Controlled with record 73 Deallocate : Deallocator; 74 Initial_Value : aliased System.Storage_Elements.Integer_Address; 75 76 Index : Direct_Index; 77 -- The index of the TCB location used by this instantiation, if it is 78 -- stored in the TCB, otherwise zero. 79 80 Next : Access_Instance; 81 -- Next instance in All_Attributes list 82 end record; 83 84 procedure Finalize (X : in out Instance); 85 86 type Node is record 87 Wrapper : Access_Dummy_Wrapper; 88 Instance : Access_Instance; 89 Next : Access_Node; 90 end record; 91 92 -- The following type is a stand-in for the actual wrapper type, which is 93 -- different for each instantiation of Ada.Task_Attributes. 94 95 type Dummy_Wrapper is record 96 Dummy_Node : aliased Node; 97 98 Value : aliased Attribute; 99 -- The generic formal type, may be controlled 100 end record; 101 102 for Dummy_Wrapper'Alignment use Standard'Maximum_Alignment; 103 -- A number of unchecked conversions involving Dummy_Wrapper_Access 104 -- sources are performed in other units (e.g. Ada.Task_Attributes). 105 -- Ensure that the designated object is always strictly enough aligned. 106 107 In_Use : Direct_Index_Vector := 0; 108 -- Set True for direct indexes that are already used (True??? type???) 109 110 All_Attributes : Access_Instance; 111 -- A linked list of all indirectly access attributes, which includes all 112 -- those that require finalization. 113 114 procedure Initialize_Attributes (T : Task_Id); 115 -- Initialize all attributes created via Ada.Task_Attributes for T. This 116 -- must be called by the creator of the task, inside Create_Task, via 117 -- soft-link Initialize_Attributes_Link. On entry, abort must be deferred 118 -- and the caller must hold no locks 119 120 procedure Finalize_Attributes (T : Task_Id); 121 -- Finalize all attributes created via Ada.Task_Attributes for T. 122 -- This is to be called by the task after it is marked as terminated 123 -- (and before it actually dies), inside Vulnerable_Free_Task, via the 124 -- soft-link Finalize_Attributes_Link. On entry, abort must be deferred 125 -- and T.L must be write-locked. 126 127end System.Tasking.Task_Attributes; 128