+++ /dev/null
-------------------------------------------------------------------------------
--- --
--- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS --
--- --
--- A D A . D Y N A M I C _ P R I O R I T I E S --
--- --
--- B o d y --
--- --
--- $Revision: 1.1 $
--- --
--- Copyright (C) 1991-2001 Florida State University --
--- --
--- 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. It is --
--- now maintained by Ada Core Technologies Inc. in cooperation with Florida --
--- State University (http://www.gnat.com). --
--- --
-------------------------------------------------------------------------------
-
-with Ada.Task_Identification;
--- used for Task_Id
--- Current_Task
--- Null_Task_Id
--- Is_Terminated
-
-with System.Task_Primitives.Operations;
--- used for Write_Lock
--- Unlock
--- Set_Priority
--- Wakeup
--- Self
-
-with System.Tasking;
--- used for Task_ID
-
-with Ada.Exceptions;
--- used for Raise_Exception
-
-with System.Tasking.Initialization;
--- used for Defer/Undefer_Abort
-
-with Unchecked_Conversion;
-
-package body Ada.Dynamic_Priorities is
-
- use System.Tasking;
- use Ada.Exceptions;
-
- function Convert_Ids is new
- Unchecked_Conversion
- (Task_Identification.Task_Id, System.Tasking.Task_ID);
-
- ------------------
- -- Get_Priority --
- ------------------
-
- -- Inquire base priority of a task
-
- function Get_Priority
- (T : Ada.Task_Identification.Task_Id :=
- Ada.Task_Identification.Current_Task)
- return System.Any_Priority is
-
- Target : constant Task_ID := Convert_Ids (T);
- Error_Message : constant String := "Trying to get the priority of a ";
-
- begin
- if Target = Convert_Ids (Ada.Task_Identification.Null_Task_Id) then
- Raise_Exception (Program_Error'Identity,
- Error_Message & "null task");
- end if;
-
- if Task_Identification.Is_Terminated (T) then
- Raise_Exception (Tasking_Error'Identity,
- Error_Message & "null task");
- end if;
-
- return Target.Common.Base_Priority;
- end Get_Priority;
-
- ------------------
- -- Set_Priority --
- ------------------
-
- -- Change base priority of a task dynamically
-
- procedure Set_Priority
- (Priority : System.Any_Priority;
- T : Ada.Task_Identification.Task_Id :=
- Ada.Task_Identification.Current_Task)
- is
- Target : constant Task_ID := Convert_Ids (T);
- Self_ID : constant Task_ID := System.Task_Primitives.Operations.Self;
- Error_Message : constant String := "Trying to set the priority of a ";
-
- begin
- if Target = Convert_Ids (Ada.Task_Identification.Null_Task_Id) then
- Raise_Exception (Program_Error'Identity,
- Error_Message & "null task");
- end if;
-
- if Task_Identification.Is_Terminated (T) then
- Raise_Exception (Tasking_Error'Identity,
- Error_Message & "terminated task");
- end if;
-
- System.Tasking.Initialization.Defer_Abort (Self_ID);
- System.Task_Primitives.Operations.Write_Lock (Target);
-
- if Self_ID = Target then
- Target.Common.Base_Priority := Priority;
- System.Task_Primitives.Operations.Set_Priority (Target, Priority);
- System.Task_Primitives.Operations.Unlock (Target);
- System.Task_Primitives.Operations.Yield;
- -- Yield is needed to enforce FIFO task dispatching.
- -- LL Set_Priority is made while holding the RTS lock so that
- -- it is inheriting high priority until it release all the RTS
- -- locks.
- -- If this is used in a system where Ceiling Locking is
- -- not enforced we may end up getting two Yield effects.
- else
- Target.New_Base_Priority := Priority;
- Target.Pending_Priority_Change := True;
- Target.Pending_Action := True;
-
- System.Task_Primitives.Operations.Wakeup
- (Target, Target.Common.State);
- -- If the task is suspended, wake it up to perform the change.
- -- check for ceiling violations ???
- System.Task_Primitives.Operations.Unlock (Target);
-
- end if;
- System.Tasking.Initialization.Undefer_Abort (Self_ID);
-
- end Set_Priority;
-
-end Ada.Dynamic_Priorities;
projects / msp430-gcc.git / blobdiff