------------------------------------------------------------------------------ -- -- -- 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 -- -- . -- -- -- -- 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;