1 ------------------------------------------------------------------------------
3 -- GNAT 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) 1995-2007, AdaCore --
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, 51 Franklin Street, Fifth Floor, --
21 -- Boston, MA 02110-1301, 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 with System.Task_Primitives.Operations;
36 -- used for Write_Lock
40 with System.Tasking.Initialization;
41 -- used for Defer_Abort
44 with Ada.Unchecked_Conversion;
46 package body System.Tasking.Task_Attributes is
48 use Task_Primitives.Operations;
49 use Tasking.Initialization;
51 function To_Access_Address is new Ada.Unchecked_Conversion
52 (Access_Node, Access_Address);
53 -- Store pointer to indirect attribute list
59 procedure Finalize (X : in out Instance) is
60 Q, To_Be_Freed : Access_Node;
61 Self_Id : constant Task_Id := Self;
64 -- Defer abort. Note that we use the nestable versions of Defer_Abort
65 -- and Undefer_Abort, because abort can already deferred when this is
66 -- called during finalization, which would cause an assert failure
69 Defer_Abort_Nestable (Self_Id);
72 -- Remove this instantiation from the list of all instantiations
76 Q : Access_Instance := All_Attributes;
79 while Q /= null and then Q /= X'Unchecked_Access loop
83 pragma Assert (Q /= null);
86 All_Attributes := Q.Next;
94 -- Free location of this attribute, for reuse
96 In_Use := In_Use and not (2**Natural (X.Index));
98 -- There is no need for finalization in this case, since controlled
99 -- types are too big to fit in the TCB.
102 -- Remove nodes for this attribute from the lists of all tasks,
103 -- and deallocate the nodes. Deallocation does finalization, if
107 C : System.Tasking.Task_Id := All_Tasks_List;
114 Q := To_Access_Node (C.Indirect_Attributes);
116 and then Q.Instance /= X'Unchecked_Access
124 C.Indirect_Attributes := To_Access_Address (Q.Next);
129 -- Can't Deallocate now since we are holding RTS_Lock
131 Q.Next := To_Be_Freed;
136 C := C.Common.All_Tasks_Link;
143 while To_Be_Freed /= null loop
145 To_Be_Freed := To_Be_Freed.Next;
146 X.Deallocate.all (Q);
149 Undefer_Abort_Nestable (Self_Id);
154 pragma Assert (False,
155 "Exception in task attribute instance finalization");
158 -------------------------
159 -- Finalize Attributes --
160 -------------------------
162 -- This is to be called just before the ATCB is deallocated.
163 -- It relies on the caller holding T.L write-lock on entry.
165 procedure Finalize_Attributes (T : Task_Id) is
167 Q : Access_Node := To_Access_Node (T.Indirect_Attributes);
170 -- Deallocate all the indirect attributes of this task
174 Q := Q.Next; P.Instance.Deallocate.all (P);
177 T.Indirect_Attributes := null;
182 pragma Assert (False,
183 "Exception in per-task attributes finalization");
184 end Finalize_Attributes;
186 ---------------------------
187 -- Initialize Attributes --
188 ---------------------------
190 -- This is to be called by System.Tasking.Stages.Create_Task
192 procedure Initialize_Attributes (T : Task_Id) is
194 Self_Id : constant Task_Id := Self;
197 Defer_Abort (Self_Id);
200 -- Initialize all the direct-access attributes of this task
206 T.Direct_Attributes (P.Index) :=
207 Direct_Attribute_Element
208 (System.Storage_Elements.To_Address (P.Initial_Value));
215 Undefer_Abort (Self_Id);
220 pragma Assert (False);
221 end Initialize_Attributes;
223 end System.Tasking.Task_Attributes;