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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 --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-2007, 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, 51 Franklin Street, Fifth Floor, --
-- Boston, MA 02110-1301, 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 a Solaris version of this package
-- Make a careful study of all signals available under the OS, to see which
-- need to be reserved, kept always unmasked, or kept always unmasked.
-- Be on the lookout for special signals that may be used by the thread
-- library.
package body System.Interrupt_Management is
use Interfaces.C;
use System.OS_Interface;
type Interrupt_List is array (Interrupt_ID range <>) of Interrupt_ID;
Exception_Interrupts : constant Interrupt_List :=
(SIGFPE, SIGILL, SIGSEGV, SIGBUS);
Unreserve_All_Interrupts : Interfaces.C.int;
pragma Import
(C, Unreserve_All_Interrupts, "__gl_unreserve_all_interrupts");
function State (Int : Interrupt_ID) return Character;
pragma Import (C, State, "__gnat_get_interrupt_state");
-- Get interrupt state. Defined in init.c
-- The input argument is the interrupt number,
-- and the result is one of the following:
User : constant Character := 'u';
Runtime : constant Character := 'r';
Default : constant Character := 's';
-- 'n' this interrupt not set by any Interrupt_State pragma
-- 'u' Interrupt_State pragma set state to User
-- 'r' Interrupt_State pragma set state to Runtime
-- 's' Interrupt_State pragma set state to System (use "default"
-- system handler)
----------------------
-- Notify_Exception --
----------------------
-- This function identifies the Ada exception to be raised using the
-- information when the system received a synchronous signal. Since this
-- function is machine and OS dependent, different code has to be provided
-- for different target.
procedure Notify_Exception
(signo : Signal;
info : access siginfo_t;
context : access ucontext_t);
----------------------
-- Notify_Exception --
----------------------
procedure Notify_Exception
(signo : Signal;
info : access siginfo_t;
context : access ucontext_t)
is
begin
-- Perform the necessary context adjustments prior to a raise
-- from a signal handler.
Adjust_Context_For_Raise (signo, context.all'Address);
-- Check that treatment of exception propagation here
-- is consistent with treatment of the abort signal in
-- System.Task_Primitives.Operations.
case signo is
when SIGFPE =>
case info.si_code is
when FPE_INTDIV |
FPE_INTOVF |
FPE_FLTDIV |
FPE_FLTOVF |
FPE_FLTUND |
FPE_FLTRES |
FPE_FLTINV |
FPE_FLTSUB =>
raise Constraint_Error;
when others =>
pragma Assert (False);
null;
end case;
when SIGILL | SIGSEGV | SIGBUS =>
raise Storage_Error;
when others =>
pragma Assert (False);
null;
end case;
end Notify_Exception;
----------------
-- Initialize --
----------------
Initialized : Boolean := False;
procedure Initialize is
act : aliased struct_sigaction;
old_act : aliased struct_sigaction;
mask : aliased sigset_t;
Result : Interfaces.C.int;
begin
if Initialized then
return;
end if;
Initialized := True;
-- Need to call pthread_init very early because it is doing signal
-- initializations.
pthread_init;
-- Change this if you want to use another signal for task abort.
-- SIGTERM might be a good one.
Abort_Task_Interrupt := SIGABRT;
act.sa_handler := Notify_Exception'Address;
-- Set sa_flags to SA_NODEFER so that during the handler execution
-- we do not change the Signal_Mask to be masked for the Signal.
-- This is a temporary fix to the problem that the Signal_Mask is
-- not restored after the exception (longjmp) from the handler.
-- The right fix should be made in sigsetjmp so that we save
-- the Signal_Set and restore it after a longjmp.
-- In that case, this field should be changed back to 0. ??? (Dong-Ik)
act.sa_flags := 16;
Result := sigemptyset (mask'Access);
pragma Assert (Result = 0);
-- ??? For the same reason explained above, we can't mask these signals
-- because otherwise we won't be able to catch more than one signal.
act.sa_mask := mask;
pragma Assert (Keep_Unmasked = (Interrupt_ID'Range => False));
pragma Assert (Reserve = (Interrupt_ID'Range => False));
for J in Exception_Interrupts'Range loop
if State (Exception_Interrupts (J)) /= User then
Keep_Unmasked (Exception_Interrupts (J)) := True;
Reserve (Exception_Interrupts (J)) := True;
if State (Exception_Interrupts (J)) /= Default then
Result :=
sigaction
(Signal (Exception_Interrupts (J)), act'Unchecked_Access,
old_act'Unchecked_Access);
pragma Assert (Result = 0);
end if;
end if;
end loop;
if State (Abort_Task_Interrupt) /= User then
Keep_Unmasked (Abort_Task_Interrupt) := True;
Reserve (Abort_Task_Interrupt) := True;
end if;
-- Set SIGINT to unmasked state as long as it's
-- not in "User" state. Check for Unreserve_All_Interrupts last
if State (SIGINT) /= User then
Keep_Unmasked (SIGINT) := True;
Reserve (SIGINT) := True;
end if;
-- Check all signals for state that requires keeping them
-- unmasked and reserved
for J in Interrupt_ID'Range loop
if State (J) = Default or else State (J) = Runtime then
Keep_Unmasked (J) := True;
Reserve (J) := True;
end if;
end loop;
-- Add the set of signals that must always be unmasked for this target
for J in Unmasked'Range loop
Keep_Unmasked (Interrupt_ID (Unmasked (J))) := True;
Reserve (Interrupt_ID (Unmasked (J))) := True;
end loop;
-- Add target-specific reserved signals
for J in Reserved'Range loop
Reserve (Interrupt_ID (Reserved (J))) := True;
end loop;
-- Process pragma Unreserve_All_Interrupts. This overrides any
-- settings due to pragma Interrupt_State:
if Unreserve_All_Interrupts /= 0 then
Keep_Unmasked (SIGINT) := False;
Reserve (SIGINT) := False;
end if;
-- We do not have Signal 0 in reality. We just use this value to
-- identify not existing signals (see s-intnam.ads). Therefore, Signal 0
-- should not be used in all signal related operations hence mark it as
-- reserved.
Reserve (0) := True;
end Initialize;
end System.Interrupt_Management;
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