Package Name: system.interrupt_management
------------------------------------------------------------------------------
-- --
-- GNU ADA RUNTIME LIBRARY (GNARL) COMPONENTS --
-- --
-- S Y S T E M . I N T E R R U P T _ M A N A G E M E N T --
-- --
-- S p e c --
-- (Version for new GNARL) --
-- --
-- $Revision: 1.1 $ --
-- --
-- Copyright (C) 1991,92,93,94,95,1996 Free Software Foundation, Inc. --
-- --
-- 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 System.OS_Interface;
-- used for Signal
-- sigset_t
package System.Interrupt_Management is
pragma Elaborate_Body;
type Interrupt_Mask is limited private;
type Interrupt_ID is new System.OS_Interface.Signal;
type Interrupt_Set is array (Interrupt_ID) of Boolean;
-- The following objects serve as constants, but are initialized
-- in the body to aid portability. This permits us
-- to use more portable names for interrupts,
-- where distinct names may map to the same interrupt ID value.
-- For example, suppose SIGRARE is a signal that is not defined on
-- all systems, but is always reserved when it is defined.
-- If we have the convention that ID zero is not used for any "real"
-- signals, and SIGRARE = 0 when SIGRARE is not one of the locally
-- supported signals, we can write
-- Reserved (SIGRARE) := true;
-- and the initialization code will be portable.
Abort_Task_Interrupt : Interrupt_ID;
-- The interrupt that is used to implement task abortion,
-- if an interrupt is used for that purpose.
-- This is one of the reserved interrupts.
Keep_Unmasked : Interrupt_Set := (others => False);
-- Keep_Unmasked (I) is true iff the interrupt I is
-- one that must be kept unmasked at all times,
-- except (perhaps) for short critical sections.
-- This includes interrupts that are mapped to exceptions
-- (see System.Interrupt_Exceptions.Is_Exception), but may also
-- include interrupts (e.g. timer) that need to be kept unmasked
-- for other reasons.
-- Where interrupts are implemented as OS signals, and signal masking
-- is per-task, the interrupt should be unmasked in ALL TASKS.
Reserve : Interrupt_Set := (others => False);
-- Reserve (I) is true iff the interrupt I is one that
-- cannot be permitted to be attached to a user handler.
-- The possible reasons are many. For example,
-- it may be mapped to an exception, used to implement task abortion,
-- or used to implement time delays.
Keep_Masked : Interrupt_Set := (others => False);
-- Keep_Masked (I) is true iff the interrupt I must always be masked.
-- Where interrupts are implemented as OS signals, and signal masking
-- is per-task, the interrupt should be masked in ALL TASKS.
-- There might not be any interrupts in this class, depending on
-- the environment. For example, if interrupts are OS signals
-- and signal masking is per-task, use of the sigwait operation
-- requires the signal be masked in all tasks.
private
type Interrupt_Mask is new System.OS_Interface.sigset_t;
-- in some implementation Interrupt_Mask can be represented
-- as a linked list.
procedure Initialize;
-- to advertise the work done by the body
end System.Interrupt_Management;