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173 | ------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S Y S T E M . S O F T _ L I N K S --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-2023, Free Software Foundation, Inc. --
-- --
-- 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 3, 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. --
-- --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception, --
-- version 3.1, as published by the Free Software Foundation. --
-- --
-- You should have received a copy of the GNU General Public License and --
-- a copy of the GCC Runtime Library Exception along with this program; --
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
-- <http://www.gnu.org/licenses/>. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This is a Ravenscar bare board version of this body. Tasking version of
-- these functions are always used.
with System.Tasking;
with System.Task_Primitives.Operations;
package body System.Soft_Links is
use System.Task_Primitives.Operations;
use type System.Tasking.Termination_Handler;
----------------
-- Local data --
----------------
Caller_Priority : Any_Priority;
-- Task's active priority when the global lock is seized. This priority is
-- restored when the task releases the global lock.
----------------------------
-- Get_Current_Excep_Soft --
----------------------------
function Get_Current_Excep_Soft return EOA is
begin
return Self.Common.Compiler_Data.Current_Excep'Access;
end Get_Current_Excep_Soft;
------------------------
-- Get_GNAT_Exception --
------------------------
function Get_GNAT_Exception return Ada.Exceptions.Exception_Id is
begin
return Ada.Exceptions.Exception_Identity (Get_Current_Excep.all.all);
end Get_GNAT_Exception;
-------------------
-- Adafinal_Soft --
-------------------
procedure Adafinal_Soft is
begin
-- Handle normal task termination by the environment task, but only for
-- the normal task termination. Abnormal termination is not supported by
-- this run time, and in the case of Unhandled_Exception the last chance
-- handler is invoked (which does not return).
Task_Termination_Handler.all (Ada.Exceptions.Null_Occurrence);
-- Here we should typically finalize all library-level controlled
-- objects. However, in Ravenscar tasks (including the environment task)
-- are non-terminating, so we avoid finalization.
-- We used to raise a Program_Error here to signal the task termination
-- event in order to avoid silent task death. It has been removed
-- because the Ada.Task_Termination functionality serves the same
-- purpose in a more flexible (and standard) way. In addition, this
-- exception triggered a second execution of the termination handler
-- (if any was installed).
end Adafinal_Soft;
--------------------
-- Task_Lock_Soft --
--------------------
procedure Task_Lock_Soft is
Self_Id : constant System.Tasking.Task_Id := Self;
begin
Self_Id.Common.Global_Task_Lock_Nesting :=
Self_Id.Common.Global_Task_Lock_Nesting + 1;
if Self_Id.Common.Global_Task_Lock_Nesting = 1 then
declare
Prio : constant System.Any_Priority := Get_Priority (Self_Id);
begin
-- Increase priority
Set_Priority (Self_Id, System.Any_Priority'Last);
-- Store caller's active priority so that it can be later restored
-- when releasing the global lock.
Caller_Priority := Prio;
end;
end if;
end Task_Lock_Soft;
---------------------------
-- Task_Termination_Soft --
---------------------------
procedure Task_Termination_Soft (Except : EO) is
pragma Unreferenced (Except);
Self_Id : constant System.Tasking.Task_Id := Self;
TH : System.Tasking.Termination_Handler := null;
begin
-- Raise the priority to prevent race conditions when using
-- System.Tasking.Fall_Back_Handler.
Set_Priority (Self_Id, Any_Priority'Last);
TH := System.Tasking.Fall_Back_Handler;
-- Restore original priority after retrieving shared data
Set_Priority (Self_Id, Self_Id.Common.Base_Priority);
-- Execute the task termination handler if we found it
if TH /= null then
TH.all (Self_Id);
end if;
end Task_Termination_Soft;
----------------------
-- Task_Unlock_Soft --
----------------------
procedure Task_Unlock_Soft is
Self_Id : constant System.Tasking.Task_Id := Self;
begin
pragma Assert (Self_Id.Common.Global_Task_Lock_Nesting > 0);
Self_Id.Common.Global_Task_Lock_Nesting :=
Self_Id.Common.Global_Task_Lock_Nesting - 1;
if Self_Id.Common.Global_Task_Lock_Nesting = 0 then
-- Restore the task's active priority
Set_Priority (Self_Id, Caller_Priority);
end if;
end Task_Unlock_Soft;
end System.Soft_Links;
|