------------------------------------------------------------------------------ -- -- -- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS -- -- -- -- S Y S T E M . T A S K I N G . P R O T E C T E D _ O B J E C T S -- -- -- -- B o d y -- -- -- -- Copyright (C) 1991-1994, Florida State University -- -- Copyright (C) 1995-2004, Ada Core Technologies -- -- -- -- GNARL 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. GNARL 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 GNARL; see file COPYING. If not, write -- -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- -- MA 02111-1307, 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. -- -- -- -- GNARL was developed by the GNARL team at Florida State University. -- -- Extensive contributions were provided by Ada Core Technologies, Inc. -- -- -- ------------------------------------------------------------------------------ pragma Polling (Off); -- Turn off polling, we do not want ATC polling to take place during -- tasking operations. It causes infinite loops and other problems. with System.Task_Primitives.Operations; -- used for Write_Lock -- Unlock -- Self with System.Parameters; -- used for Runtime_Traces with System.Traces; -- used for Send_Trace_Info with System.Soft_Links.Tasking; -- Used for Init_Tasking_Soft_Links package body System.Tasking.Protected_Objects is use System.Task_Primitives.Operations; use System.Traces; ------------------------- -- Finalize_Protection -- ------------------------- procedure Finalize_Protection (Object : in out Protection) is begin Finalize_Lock (Object.L'Unrestricted_Access); end Finalize_Protection; --------------------------- -- Initialize_Protection -- --------------------------- procedure Initialize_Protection (Object : Protection_Access; Ceiling_Priority : Integer) is Init_Priority : Integer := Ceiling_Priority; begin if Init_Priority = Unspecified_Priority then Init_Priority := System.Priority'Last; end if; Initialize_Lock (Init_Priority, Object.L'Access); Object.Ceiling := System.Any_Priority (Init_Priority); end Initialize_Protection; ---------- -- Lock -- ---------- procedure Lock (Object : Protection_Access) is Ceiling_Violation : Boolean; begin -- The lock is made without defering abortion. -- Therefore the abortion has to be deferred before calling this -- routine. This means that the compiler has to generate a Defer_Abort -- call before the call to Lock. -- The caller is responsible for undeferring abortion, and compiler -- generated calls must be protected with cleanup handlers to ensure -- that abortion is undeferred in all cases. Write_Lock (Object.L'Access, Ceiling_Violation); if Parameters.Runtime_Traces then Send_Trace_Info (PO_Lock); end if; if Ceiling_Violation then raise Program_Error; end if; -- We are entering in a protected action, so that we increase the -- protected object nesting level (if pragma Detect_Blocking is -- active). if Detect_Blocking then declare Self_Id : constant Task_Id := Self; begin Self_Id.Common.Protected_Action_Nesting := Self_Id.Common.Protected_Action_Nesting + 1; end; end if; end Lock; -------------------- -- Lock_Read_Only -- -------------------- procedure Lock_Read_Only (Object : Protection_Access) is Ceiling_Violation : Boolean; begin Read_Lock (Object.L'Access, Ceiling_Violation); if Parameters.Runtime_Traces then Send_Trace_Info (PO_Lock); end if; if Ceiling_Violation then raise Program_Error; end if; -- We are entering in a protected action, so that we increase the -- protected object nesting level (if pragma Detect_Blocking is -- active). if Detect_Blocking then declare Self_Id : constant Task_Id := Self; begin Self_Id.Common.Protected_Action_Nesting := Self_Id.Common.Protected_Action_Nesting + 1; end; end if; end Lock_Read_Only; ------------ -- Unlock -- ------------ procedure Unlock (Object : Protection_Access) is begin -- We are exiting from a protected action, so that we decrease the -- protected object nesting level (if pragma Detect_Blocking is -- active). if Detect_Blocking then declare Self_Id : constant Task_Id := Self; begin -- Cannot call this procedure without being within a protected -- action. pragma Assert (Self_Id.Common.Protected_Action_Nesting > 0); Self_Id.Common.Protected_Action_Nesting := Self_Id.Common.Protected_Action_Nesting - 1; end; end if; Unlock (Object.L'Access); if Parameters.Runtime_Traces then Send_Trace_Info (PO_Unlock); end if; end Unlock; begin -- Ensure that tasking soft links are set when using protected objects System.Soft_Links.Tasking.Init_Tasking_Soft_Links; end System.Tasking.Protected_Objects;