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diff --git a/gcc/ada/s-interr.ads b/gcc/ada/s-interr.ads new file mode 100644 index 00000000000..e6cc8836395 --- /dev/null +++ b/gcc/ada/s-interr.ads @@ -0,0 +1,281 @@ +------------------------------------------------------------------------------ +-- -- +-- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS -- +-- -- +-- S Y S T E M . I N T E R R U P T S -- +-- -- +-- S p e c -- +-- -- +-- $Revision: 1.18 $ +-- -- +-- Copyright (C) 1992-2001 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). -- +-- -- +------------------------------------------------------------------------------ + +-- Note: the compiler generates direct calls to this interface, via Rtsfind. +-- Any changes to this interface may require corresponding compiler changes. + +-- This package encapsulates the implementation of interrupt or signal +-- handlers. It is logically an extension of the body of Ada.Interrupts. +-- It is made a child of System to allow visibility of various +-- runtime system internal data and operations. + +-- See System.Interrupt_Management for core interrupt/signal interfaces. + +-- These two packages are separated in order to allow +-- System.Interrupt_Management to be used without requiring the whole +-- tasking implementation to be linked and elaborated. + +with System.Tasking; +-- used for Task_ID + +with System.Tasking.Protected_Objects.Entries; +-- used for Protection_Entries + +with System.OS_Interface; +-- used for Max_Interrupt + +package System.Interrupts is + + pragma Elaborate_Body; + -- Comment needed on why this is here ??? + + ------------------------- + -- Constants and types -- + ------------------------- + + Default_Interrupt_Priority : constant System.Interrupt_Priority := + System.Interrupt_Priority'Last; + -- Default value used when a pragma Interrupt_Handler or Attach_Handler is + -- specified without an Interrupt_Priority pragma, see D.3(10). + + type Ada_Interrupt_ID is range 0 .. System.OS_Interface.Max_Interrupt; + -- Avoid inheritance by Ada.Interrupts.Interrupt_ID of unwanted operations + + type Interrupt_ID is range 0 .. System.OS_Interface.Max_Interrupt; + + type Parameterless_Handler is access protected procedure; + + ---------------------- + -- General services -- + ---------------------- + + -- Attempt to attach a Handler to an Interrupt to which an Entry is + -- already bound will raise a Program_Error. + + function Is_Reserved (Interrupt : Interrupt_ID) return Boolean; + + function Is_Entry_Attached (Interrupt : Interrupt_ID) return Boolean; + + function Is_Handler_Attached (Interrupt : Interrupt_ID) return Boolean; + + function Current_Handler + (Interrupt : Interrupt_ID) + return Parameterless_Handler; + + -- Calling the following procedures with New_Handler = null + -- and Static = true means that we want to modify the current handler + -- regardless of the previous handler's binding status. + -- (i.e. we do not care whether it is a dynamic or static handler) + + procedure Attach_Handler + (New_Handler : Parameterless_Handler; + Interrupt : Interrupt_ID; + Static : Boolean := False); + + procedure Exchange_Handler + (Old_Handler : out Parameterless_Handler; + New_Handler : Parameterless_Handler; + Interrupt : Interrupt_ID; + Static : Boolean := False); + + procedure Detach_Handler + (Interrupt : Interrupt_ID; + Static : Boolean := False); + + function Reference + (Interrupt : Interrupt_ID) + return System.Address; + + --------------------------------- + -- Interrupt entries services -- + --------------------------------- + + -- Routines needed for Interrupt Entries + -- Attempt to bind an Entry to an Interrupt to which a Handler is + -- already attached will raise a Program_Error. + + procedure Bind_Interrupt_To_Entry + (T : System.Tasking.Task_ID; + E : System.Tasking.Task_Entry_Index; + Int_Ref : System.Address); + + procedure Detach_Interrupt_Entries (T : System.Tasking.Task_ID); + -- This procedure detaches all the Interrupt Entries bound to a task. + + ------------------------------- + -- POSIX.5 signals services -- + ------------------------------- + + -- Routines needed for POSIX dot5 POSIX_Signals + + procedure Block_Interrupt (Interrupt : Interrupt_ID); + -- Block the Interrupt on the process level + + procedure Unblock_Interrupt (Interrupt : Interrupt_ID); + + function Unblocked_By + (Interrupt : Interrupt_ID) + return System.Tasking.Task_ID; + -- It returns the ID of the last Task which Unblocked this Interrupt. + -- It returns Null_Task if no tasks have ever requested the + -- Unblocking operation or the Interrupt is currently Blocked. + + function Is_Blocked (Interrupt : Interrupt_ID) return Boolean; + -- Comment needed ??? + + procedure Ignore_Interrupt (Interrupt : Interrupt_ID); + -- Set the sigacion for the interrupt to SIG_IGN. + + procedure Unignore_Interrupt (Interrupt : Interrupt_ID); + -- Comment needed ??? + + function Is_Ignored (Interrupt : Interrupt_ID) return Boolean; + -- Comment needed ??? + + -- Note : Direct calls to sigaction, sigprocmask, thr_sigsetmask or any + -- other low-level interface that changes the signal action or signal mask + -- needs a careful thought. + + -- One may acheive the effect of system calls first making RTS blocked + -- (by calling Block_Interrupt) for the signal under consideration. + -- This will make all the tasks in RTS blocked for the Interrupt. + + ---------------------- + -- Protection types -- + ---------------------- + + -- Routines and types needed to implement Interrupt_Handler and + -- Attach_Handler. + + -- There are two kinds of protected objects that deal with interrupts: + + -- (1) Only Interrupt_Handler pragmas are used. We need to be able to + -- tell if an Interrupt_Handler applies to a given procedure, so + -- Register_Interrupt_Handler has to be called for all the potential + -- handlers, it should be done by calling Register_Interrupt_Handler + -- with the handler code address. On finalization, which can happen only + -- has part of library level finalization since PO with + -- Interrupt_Handler pragmas can only be declared at library level, + -- nothing special needs to be done since the default handlers have been + -- restored as part of task completion which is done just before global + -- finalization. Dynamic_Interrupt_Protection should be used in this + -- case. + + -- (2) Attach_Handler pragmas are used, and possibly Interrupt_Handler + -- pragma. We need to attach the handlers to the given interrupts when + -- the objet is elaborated. This should be done by constructing an array + -- of pairs (interrupt, handler) from the pragmas and calling + -- Install_Handlers with it (types to be used are New_Handler_Item and + -- New_Handler_Array). On finalization, we need to restore the handlers + -- that were installed before the elaboration of the PO, so we need to + -- store these previous handlers. This is also done by Install_Handlers, + -- the room for these informations is provided by adding a discriminant + -- which is the number of Attach_Handler pragmas and an array of this + -- size in the protection type, Static_Interrupt_Protection. + + procedure Register_Interrupt_Handler + (Handler_Addr : System.Address); + -- This routine should be called by the compiler to allow the + -- handler be used as an Interrupt Handler. That means call this + -- procedure for each pragma Interrup_Handler providing the + -- address of the handler (not including the pointer to the + -- actual PO, this way this routine is called only once for + -- each type definition of PO). + + type Static_Handler_Index is range 0 .. Integer'Last; + subtype Positive_Static_Handler_Index is + Static_Handler_Index range 1 .. Static_Handler_Index'Last; + -- Comment needed ??? + + type Previous_Handler_Item is record + Interrupt : Interrupt_ID; + Handler : Parameterless_Handler; + Static : Boolean; + end record; + -- Contains all the information needed to restore a previous handler. + + type Previous_Handler_Array is array + (Positive_Static_Handler_Index range <>) of Previous_Handler_Item; + + type New_Handler_Item is record + Interrupt : Interrupt_ID; + Handler : Parameterless_Handler; + end record; + -- Contains all the information from an Attach_Handler pragma. + + type New_Handler_Array is + array (Positive_Static_Handler_Index range <>) of New_Handler_Item; + -- Comment needed ??? + + -- Case (1) + + type Dynamic_Interrupt_Protection is new + Tasking.Protected_Objects.Entries.Protection_Entries with null record; + + -- ??? Finalize is not overloaded since we currently have no + -- way to detach the handlers during library level finalization. + + function Has_Interrupt_Or_Attach_Handler + (Object : access Dynamic_Interrupt_Protection) return Boolean; + -- Returns True. + + -- Case (2) + + type Static_Interrupt_Protection + (Num_Entries : Tasking.Protected_Objects.Protected_Entry_Index; + Num_Attach_Handler : Static_Handler_Index) + is new + Tasking.Protected_Objects.Entries.Protection_Entries (Num_Entries) with + record + Previous_Handlers : Previous_Handler_Array (1 .. Num_Attach_Handler); + end record; + + function Has_Interrupt_Or_Attach_Handler + (Object : access Static_Interrupt_Protection) + return Boolean; + -- Returns True. + + procedure Finalize (Object : in out Static_Interrupt_Protection); + -- Restore previous handlers as required by C.3.1(12) then call + -- Finalize (Protection). + + procedure Install_Handlers + (Object : access Static_Interrupt_Protection; + New_Handlers : in New_Handler_Array); + -- Store the old handlers in Object.Previous_Handlers and install + -- the new static handlers. + +end System.Interrupts; |