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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S Y S T E M . S O F T _ L I N K S . T A S K I N G --
-- --
-- B o d y --
-- --
-- Copyright (C) 2004-2014, 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. --
-- --
------------------------------------------------------------------------------
pragma Style_Checks (All_Checks);
-- Turn off subprogram alpha ordering check, since we group soft link bodies
-- and dummy soft link bodies together separately in this unit.
pragma Polling (Off);
-- Turn polling off for this package. We don't need polling during any of the
-- routines in this package, and more to the point, if we try to poll it can
-- cause infinite loops.
with Ada.Exceptions;
with Ada.Exceptions.Is_Null_Occurrence;
with System.Task_Primitives.Operations;
with System.Tasking;
with System.Stack_Checking;
package body System.Soft_Links.Tasking is
package STPO renames System.Task_Primitives.Operations;
package SSL renames System.Soft_Links;
use Ada.Exceptions;
use type System.Tasking.Task_Id;
use type System.Tasking.Termination_Handler;
----------------
-- Local Data --
----------------
Initialized : Boolean := False;
-- Boolean flag that indicates whether the tasking soft links have
-- already been set.
-----------------------------------------------------------------
-- Tasking Versions of Services Needed by Non-Tasking Programs --
-----------------------------------------------------------------
function Get_Jmpbuf_Address return Address;
procedure Set_Jmpbuf_Address (Addr : Address);
-- Get/Set Jmpbuf_Address for current task
function Get_Sec_Stack_Addr return Address;
procedure Set_Sec_Stack_Addr (Addr : Address);
-- Get/Set location of current task's secondary stack
procedure Timed_Delay_T (Time : Duration; Mode : Integer);
-- Task-safe version of SSL.Timed_Delay
procedure Task_Termination_Handler_T (Excep : SSL.EO);
-- Task-safe version of the task termination procedure
function Get_Stack_Info return Stack_Checking.Stack_Access;
-- Get access to the current task's Stack_Info
--------------------------
-- Soft-Link Get Bodies --
--------------------------
function Get_Jmpbuf_Address return Address is
begin
return STPO.Self.Common.Compiler_Data.Jmpbuf_Address;
end Get_Jmpbuf_Address;
function Get_Sec_Stack_Addr return Address is
begin
return Result : constant Address :=
STPO.Self.Common.Compiler_Data.Sec_Stack_Addr
do
pragma Assert (Result /= Null_Address);
end return;
end Get_Sec_Stack_Addr;
function Get_Stack_Info return Stack_Checking.Stack_Access is
begin
return STPO.Self.Common.Compiler_Data.Pri_Stack_Info'Access;
end Get_Stack_Info;
--------------------------
-- Soft-Link Set Bodies --
--------------------------
procedure Set_Jmpbuf_Address (Addr : Address) is
begin
STPO.Self.Common.Compiler_Data.Jmpbuf_Address := Addr;
end Set_Jmpbuf_Address;
procedure Set_Sec_Stack_Addr (Addr : Address) is
begin
STPO.Self.Common.Compiler_Data.Sec_Stack_Addr := Addr;
end Set_Sec_Stack_Addr;
-------------------
-- Timed_Delay_T --
-------------------
procedure Timed_Delay_T (Time : Duration; Mode : Integer) is
Self_Id : constant System.Tasking.Task_Id := STPO.Self;
begin
-- In case pragma Detect_Blocking is active then Program_Error
-- must be raised if this potentially blocking operation
-- is called from a protected operation.
if System.Tasking.Detect_Blocking
and then Self_Id.Common.Protected_Action_Nesting > 0
then
raise Program_Error with "potentially blocking operation";
else
Abort_Defer.all;
STPO.Timed_Delay (Self_Id, Time, Mode);
Abort_Undefer.all;
end if;
end Timed_Delay_T;
--------------------------------
-- Task_Termination_Handler_T --
--------------------------------
procedure Task_Termination_Handler_T (Excep : SSL.EO) is
Self_Id : constant System.Tasking.Task_Id := STPO.Self;
Cause : System.Tasking.Cause_Of_Termination;
EO : Ada.Exceptions.Exception_Occurrence;
begin
-- We can only be here because we are terminating the environment task.
-- Task termination for all other tasks is handled in the Task_Wrapper.
-- We do not want to enable this check and e.g. call System.OS_Lib.Abort
-- here because some restricted run-times may not have System.OS_Lib
-- (e.g. JVM), and calling abort may do more harm than good to the
-- main application.
pragma Assert (Self_Id = STPO.Environment_Task);
-- Normal task termination
if Is_Null_Occurrence (Excep) then
Cause := System.Tasking.Normal;
Ada.Exceptions.Save_Occurrence (EO, Ada.Exceptions.Null_Occurrence);
-- Abnormal task termination
elsif Exception_Identity (Excep) = Standard'Abort_Signal'Identity then
Cause := System.Tasking.Abnormal;
Ada.Exceptions.Save_Occurrence (EO, Ada.Exceptions.Null_Occurrence);
-- Termination because of an unhandled exception
else
Cause := System.Tasking.Unhandled_Exception;
Ada.Exceptions.Save_Occurrence (EO, Excep);
end if;
-- There is no need for explicit protection against race conditions for
-- this part because it can only be executed by the environment task
-- after all the other tasks have been finalized. Note that there is no
-- fall-back handler which could apply to this environment task because
-- it has no parents, and, as specified in ARM C.7.3 par. 9/2, "the
-- fall-back handler applies only to the dependent tasks of the task".
if Self_Id.Common.Specific_Handler /= null then
Self_Id.Common.Specific_Handler.all (Cause, Self_Id, EO);
end if;
end Task_Termination_Handler_T;
-----------------------------
-- Init_Tasking_Soft_Links --
-----------------------------
procedure Init_Tasking_Soft_Links is
begin
-- Set links only if not set already
if not Initialized then
-- Mark tasking soft links as initialized
Initialized := True;
-- The application being executed uses tasking so that the tasking
-- version of the following soft links need to be used.
SSL.Get_Jmpbuf_Address := Get_Jmpbuf_Address'Access;
SSL.Set_Jmpbuf_Address := Set_Jmpbuf_Address'Access;
SSL.Get_Sec_Stack_Addr := Get_Sec_Stack_Addr'Access;
SSL.Get_Stack_Info := Get_Stack_Info'Access;
SSL.Set_Sec_Stack_Addr := Set_Sec_Stack_Addr'Access;
SSL.Timed_Delay := Timed_Delay_T'Access;
SSL.Task_Termination_Handler := Task_Termination_Handler_T'Access;
-- No need to create a new secondary stack, since we will use the
-- default one created in s-secsta.adb.
SSL.Set_Sec_Stack_Addr (SSL.Get_Sec_Stack_Addr_NT);
SSL.Set_Jmpbuf_Address (SSL.Get_Jmpbuf_Address_NT);
end if;
pragma Assert (Get_Sec_Stack_Addr /= Null_Address);
end Init_Tasking_Soft_Links;
end System.Soft_Links.Tasking;
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