| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT RUN-TIME COMPONENTS -- |
| -- -- |
| -- A D A . T A S K _ T E R M I N A T I O N -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 2005-2006, 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 2, 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. See the GNU General Public License -- |
| -- for more details. You should have received a copy of the GNU General -- |
| -- Public License distributed with GNAT; see file COPYING. If not, write -- |
| -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, -- |
| -- Boston, MA 02110-1301, USA. -- |
| -- -- |
| -- As a special exception, if other files instantiate generics from this -- |
| -- unit, or you link this unit with other files to produce an executable, -- |
| -- this unit does not by itself cause the resulting executable to be -- |
| -- covered by the GNU General Public License. This exception does not -- |
| -- however invalidate any other reasons why the executable file might be -- |
| -- covered by the GNU Public License. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| with System.Tasking; |
| -- used for Task_Id |
| |
| with System.Task_Primitives.Operations; |
| -- used for Self |
| -- Write_Lock |
| -- Unlock |
| -- Lock_RTS |
| -- Unlock_RTS |
| |
| with System.Parameters; |
| -- used for Single_Lock |
| |
| with System.Soft_Links; |
| -- use for Abort_Defer |
| -- Abort_Undefer |
| |
| with Unchecked_Conversion; |
| |
| package body Ada.Task_Termination is |
| |
| use type Ada.Task_Identification.Task_Id; |
| |
| package STPO renames System.Task_Primitives.Operations; |
| package SSL renames System.Soft_Links; |
| |
| use System.Parameters; |
| |
| ----------------------- |
| -- Local subprograms -- |
| ----------------------- |
| |
| function To_TT is new Unchecked_Conversion |
| (System.Tasking.Termination_Handler, Termination_Handler); |
| |
| function To_ST is new Unchecked_Conversion |
| (Termination_Handler, System.Tasking.Termination_Handler); |
| |
| function To_Task_Id is new Unchecked_Conversion |
| (Ada.Task_Identification.Task_Id, System.Tasking.Task_Id); |
| |
| ----------------------------------- |
| -- Current_Task_Fallback_Handler -- |
| ----------------------------------- |
| |
| function Current_Task_Fallback_Handler return Termination_Handler is |
| begin |
| -- There is no need for explicit protection against race conditions |
| -- for this function because this function can only be executed by |
| -- Self, and the Fall_Back_Handler can only be modified by Self. |
| |
| return To_TT (STPO.Self.Common.Fall_Back_Handler); |
| end Current_Task_Fallback_Handler; |
| |
| ------------------------------------- |
| -- Set_Dependents_Fallback_Handler -- |
| ------------------------------------- |
| |
| procedure Set_Dependents_Fallback_Handler |
| (Handler : Termination_Handler) |
| is |
| Self : constant System.Tasking.Task_Id := STPO.Self; |
| |
| begin |
| SSL.Abort_Defer.all; |
| |
| if Single_Lock then |
| STPO.Lock_RTS; |
| end if; |
| |
| STPO.Write_Lock (Self); |
| |
| Self.Common.Fall_Back_Handler := To_ST (Handler); |
| |
| STPO.Unlock (Self); |
| |
| if Single_Lock then |
| STPO.Unlock_RTS; |
| end if; |
| |
| SSL.Abort_Undefer.all; |
| end Set_Dependents_Fallback_Handler; |
| |
| -------------------------- |
| -- Set_Specific_Handler -- |
| -------------------------- |
| |
| procedure Set_Specific_Handler |
| (T : Ada.Task_Identification.Task_Id; |
| Handler : Termination_Handler) |
| is |
| begin |
| -- Tasking_Error is raised if the task identified by T has already |
| -- terminated. Program_Error is raised if the value of T is |
| -- Null_Task_Id. |
| |
| if T = Ada.Task_Identification.Null_Task_Id then |
| raise Program_Error; |
| elsif Ada.Task_Identification.Is_Terminated (T) then |
| raise Tasking_Error; |
| else |
| declare |
| Target : constant System.Tasking.Task_Id := To_Task_Id (T); |
| |
| begin |
| SSL.Abort_Defer.all; |
| |
| if Single_Lock then |
| STPO.Lock_RTS; |
| end if; |
| |
| STPO.Write_Lock (Target); |
| |
| Target.Common.Specific_Handler := To_ST (Handler); |
| |
| STPO.Unlock (Target); |
| |
| if Single_Lock then |
| STPO.Unlock_RTS; |
| end if; |
| |
| SSL.Abort_Undefer.all; |
| end; |
| end if; |
| end Set_Specific_Handler; |
| |
| ---------------------- |
| -- Specific_Handler -- |
| ---------------------- |
| |
| function Specific_Handler |
| (T : Ada.Task_Identification.Task_Id) return Termination_Handler |
| is |
| begin |
| -- Tasking_Error is raised if the task identified by T has already |
| -- terminated. Program_Error is raised if the value of T is |
| -- Null_Task_Id. |
| |
| if T = Ada.Task_Identification.Null_Task_Id then |
| raise Program_Error; |
| elsif Ada.Task_Identification.Is_Terminated (T) then |
| raise Tasking_Error; |
| else |
| declare |
| Target : constant System.Tasking.Task_Id := To_Task_Id (T); |
| TH : Termination_Handler; |
| |
| begin |
| SSL.Abort_Defer.all; |
| |
| if Single_Lock then |
| STPO.Lock_RTS; |
| end if; |
| |
| STPO.Write_Lock (Target); |
| |
| TH := To_TT (Target.Common.Specific_Handler); |
| |
| STPO.Unlock (Target); |
| |
| if Single_Lock then |
| STPO.Unlock_RTS; |
| end if; |
| |
| SSL.Abort_Undefer.all; |
| |
| return TH; |
| end; |
| end if; |
| end Specific_Handler; |
| |
| end Ada.Task_Termination; |
