| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS -- |
| -- -- |
| -- S Y S T E M . T A S K _ P R I M I T I V E S . O P E R A T I O N S . -- |
| -- S P E C I F I C -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- $Revision: 1.2 $ |
| -- -- |
| -- Copyright (C) 1991-2003, 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). -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| -- This is a RTEMS version of this package which uses a special |
| -- variable for Ada self which is contexted switch implicitly by RTEMS. |
| -- |
| -- This is the same as the POSIX version except that an RTEMS variable |
| -- is used instead of a POSIX key. |
| |
| separate (System.Task_Primitives.Operations) |
| package body Specific is |
| |
| -- The following gives the Ada run-time direct access to a variable |
| -- context switched by RTEMS at the lowest level. |
| |
| RTEMS_Ada_Self : System.Address; |
| pragma Import (C, RTEMS_Ada_Self, "rtems_ada_self"); |
| |
| ---------------- |
| -- Initialize -- |
| ---------------- |
| |
| procedure Initialize (Environment_Task : Task_ID) is |
| pragma Warnings (Off, Environment_Task); |
| Result : Interfaces.C.int; |
| |
| begin |
| RTEMS_Ada_Self := To_Address (Environment_Task); |
| end Initialize; |
| |
| ------------------- |
| -- Is_Valid_Task -- |
| ------------------- |
| |
| function Is_Valid_Task return Boolean is |
| begin |
| return RTEMS_Ada_Self /= System.Null_Address; |
| end Is_Valid_Task; |
| |
| --------- |
| -- Set -- |
| --------- |
| |
| procedure Set (Self_Id : Task_ID) is |
| Result : Interfaces.C.int; |
| begin |
| RTEMS_Ada_Self := To_Address (Self_Id); |
| end Set; |
| |
| ---------- |
| -- Self -- |
| ---------- |
| |
| -- To make Ada tasks and C threads interoperate better, we have added some |
| -- functionality to Self. Suppose a C main program (with threads) calls an |
| -- Ada procedure and the Ada procedure calls the tasking runtime system. |
| -- Eventually, a call will be made to self. Since the call is not coming |
| -- from an Ada task, there will be no corresponding ATCB. |
| |
| -- What we do in Self is to catch references that do not come from |
| -- recognized Ada tasks, and create an ATCB for the calling thread. |
| |
| -- The new ATCB will be "detached" from the normal Ada task master |
| -- hierarchy, much like the existing implicitly created signal-server |
| -- tasks. |
| |
| function Self return Task_ID is |
| Result : System.Address; |
| |
| begin |
| Result := RTEMS_Ada_Self; |
| |
| -- If the key value is Null, then it is a non-Ada task. |
| |
| if Result /= System.Null_Address then |
| return To_Task_Id (Result); |
| else |
| return Register_Foreign_Thread; |
| end if; |
| end Self; |
| |
| end Specific; |
