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Diffstat (limited to 'gcc/ada/s-intman-vms.ads')
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diff --git a/gcc/ada/s-intman-vms.ads b/gcc/ada/s-intman-vms.ads new file mode 100644 index 00000000000..60f410b01d7 --- /dev/null +++ b/gcc/ada/s-intman-vms.ads @@ -0,0 +1,142 @@ +------------------------------------------------------------------------------ +-- -- +-- GNU ADA 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) 1991-2003 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. -- +-- Extensive contributions were provided by Ada Core Technologies, Inc. -- +-- -- +------------------------------------------------------------------------------ + +-- This is the Alpha/VMS 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. + +-- PLEASE DO NOT add any with-clauses to this package. +-- This is designed to work for both tasking and non-tasking systems, +-- without pulling in any of the tasking support. + +-- PLEASE DO NOT remove the Elaborate_Body pragma from this package. +-- Elaboration of this package should happen early, as most other +-- initializations depend on it. +-- Forcing immediate elaboration of the body also helps to enforce +-- the design assumption that this is a second-level +-- package, just one level above System.OS_Interface, with no +-- cross-dependences. + +-- 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 +-- below are implemented as visible arrays rather than functions.) + +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. + + procedure Initialize_Interrupts; + -- On systems where there is no signal inheritance between tasks (e.g + -- VxWorks, GNU/LinuxThreads), this procedure is used to initialize + -- interrupts handling in each task. Otherwise this function should + -- only be called by initialize in this package body. + +private + + use type System.OS_Interface.unsigned_long; + + type Interrupt_Mask is new System.OS_Interface.sigset_t; + + -- Interrupts on VMS are implemented with a mailbox. A QIO read is + -- registered on the Rcv channel and the interrupt occurs by registering + -- a QIO write on the Snd channel. The maximum number of pending + -- interrupts is arbitrarily set at 1000. One nice feature of using + -- a mailbox is that it is trivially extendable to cross process + -- interrupts. + + Rcv_Interrupt_Chan : System.OS_Interface.unsigned_short := 0; + Snd_Interrupt_Chan : System.OS_Interface.unsigned_short := 0; + Interrupt_Mailbox : Interrupt_ID := 0; + Interrupt_Bufquo : System.OS_Interface.unsigned_long + := 1000 * (Interrupt_ID'Size / 8); + +end System.Interrupt_Management; |