| ------------------------------------------------------------------------------ |
| -- -- |
| -- 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) 1992-2022, 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 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; |
| |
| -- 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 abort 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 abort, |
| -- or used to implement time delays. |
| |
| 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. |
| |
| private |
| type Interrupt_Mask is new System.OS_Interface.sigset_t; |
| -- In some implementations Interrupt_Mask is represented as a linked list |
| |
| procedure Adjust_Context_For_Raise |
| (Signo : System.OS_Interface.Signal; |
| Ucontext : System.Address); |
| pragma Import |
| (C, Adjust_Context_For_Raise, "__gnat_adjust_context_for_raise"); |
| -- Target specific hook performing adjustments to the signal's machine |
| -- context, to be called before an exception may be raised from a signal |
| -- handler. This service is provided by init.c, together with the |
| -- non-tasking signal handler. |
| |
| end System.Interrupt_Management; |