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------------------------------------------------------------------------------

--                                                                          --

--                 GNAT RUN-TIME 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                                 --

--                                                                          --

--          Copyright (C) 1992-2009, 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 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    --

-- <http://www.gnu.org/licenses/>.                                          --

--                                                                          --

-- GNARL was developed by the GNARL team at Florida State University.       --

-- Extensive contributions were provided by Ada Core Technologies, Inc.     --

--                                                                          --

------------------------------------------------------------------------------

--  This is the VxWorks version of this package

--  This package encapsulates and centralizes information about all

--  uses of interrupts (or signals), including the target-dependent

--  mapping of interrupts (or signals) to exceptions.

--  Unlike the original design, System.Interrupt_Management can only

--  be used for tasking systems.

--  PLEASE DO NOT put any subprogram declarations with arguments of

--  type Interrupt_ID into the visible part of this package. The type

--  Interrupt_ID is used to derive the type in Ada.Interrupts, and

--  adding more operations to that type would be illegal according

--  to the Ada Reference Manual. This is the reason why the signals

--  sets are implemented using visible arrays rather than functions.

with System.OS_Interface;

with Interfaces.C;

package System.Interrupt_Management is

   pragma Preelaborate;

   type Interrupt_Mask is limited private;

   type Interrupt_ID is new Interfaces.C.int

     range 0 .. System.OS_Interface.Max_Interrupt;

   type Interrupt_Set is array (Interrupt_ID) of Boolean;

   subtype Signal_ID is Interrupt_ID

     range 0 .. Interfaces.C."-" (System.OS_Interface.NSIG, 1);

   type Signal_Set is array (Signal_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 : Signal_ID;

   --  The signal that is used to implement task abort if an interrupt is used

   --  for that purpose. This is one of the reserved signals.

   Keep_Unmasked : Signal_Set := (others => False);

   --  Keep_Unmasked (I) is true iff the signal I is one that must that must

   --  be kept unmasked at all times, except (perhaps) for short critical

   --  sections. This includes signals that are mapped to exceptions, but may

   --  also include interrupts (e.g. timer) that need to be kept unmasked for

   --  other reasons. Where signal masking is per-task, the signal 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 abort,

   --  or used to implement time delays.

   procedure Initialize_Interrupts;

   --  Under VxWorks, there is no signal inheritance between tasks.

   --  This procedure is used to initialize signal-to-exception mapping in

   --  each task.

   procedure Initialize;

   --  Initialize the various variables defined in this package. This procedure

   --  must be called before accessing any object from this package and can be

   --  called multiple times (only the first call has any effect).

private

   type Interrupt_Mask is new System.OS_Interface.sigset_t;

   --  In some implementation Interrupt_Mask can be represented as a linked

   --  list.

end System.Interrupt_Management;