| ------------------------------------------------------------------------------ |
| -- -- |
| -- 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 -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- $Revision: 1.1 $ |
| -- -- |
| -- Copyright (C) 1991-2001, Florida State University -- |
| -- -- |
| -- 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). -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| -- This is the default version of this package |
| |
| -- This is a Sun OS (FSU THREADS) version of this package |
| |
| -- PLEASE DO NOT add any dependences on other packages. ??? why not ??? |
| -- This package is designed to work with or without tasking support. |
| |
| -- See the other warnings in the package specification before making |
| -- any modifications to this file. |
| |
| -- 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. |
| |
| -- Since this is a multi target file, the signal <-> exception mapping |
| -- is simple minded. If you need a more precise and target specific |
| -- signal handling, create a new s-intman.adb that will fit your needs. |
| |
| -- This file assumes that: |
| -- |
| -- SIGFPE, SIGILL, SIGSEGV and SIGBUS exist. They are mapped as follows: |
| -- SIGPFE => Constraint_Error |
| -- SIGILL => Program_Error |
| -- SIGSEGV => Storage_Error |
| -- SIGBUS => Storage_Error |
| -- |
| -- SIGINT exists and will be kept unmasked unless the pragma |
| -- Unreserve_All_Interrupts is specified anywhere in the application. |
| -- |
| -- System.OS_Interface contains the following: |
| -- SIGADAABORT: the signal that will be used to abort tasks. |
| -- Unmasked: the OS specific set of signals that should be unmasked in |
| -- all the threads. SIGADAABORT is unmasked by |
| -- default |
| -- Reserved: the OS specific set of signals that are reserved. |
| |
| with Interfaces.C; |
| -- used for int and other types |
| |
| with System.OS_Interface; |
| -- used for various Constants, Signal and types |
| |
| 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"); |
| |
| ----------------------- |
| -- Local Subprograms -- |
| ----------------------- |
| |
| procedure Notify_Exception (signo : Signal); |
| -- 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. |
| |
| ---------------------- |
| -- Notify_Exception -- |
| ---------------------- |
| |
| Signal_Mask : aliased sigset_t; |
| -- The set of signals handled by Notify_Exception |
| |
| procedure Notify_Exception (signo : Signal) is |
| Result : Interfaces.C.int; |
| |
| begin |
| -- With the __builtin_longjmp, the signal mask is not restored, so we |
| -- need to restore it explicitly. |
| |
| Result := pthread_sigmask (SIG_UNBLOCK, Signal_Mask'Access, null); |
| pragma Assert (Result = 0); |
| |
| -- 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 => |
| raise Constraint_Error; |
| when SIGILL => |
| raise Program_Error; |
| when SIGSEGV => |
| raise Storage_Error; |
| when SIGBUS => |
| raise Storage_Error; |
| when others => |
| null; |
| end case; |
| end Notify_Exception; |
| |
| --------------------------- |
| -- Initialize_Interrupts -- |
| --------------------------- |
| |
| -- Nothing needs to be done on this platform. |
| |
| procedure Initialize_Interrupts is |
| begin |
| null; |
| end Initialize_Interrupts; |
| |
| ------------------------- |
| -- Package Elaboration -- |
| ------------------------- |
| |
| begin |
| declare |
| act : aliased struct_sigaction; |
| old_act : aliased struct_sigaction; |
| Result : Interfaces.C.int; |
| |
| begin |
| -- Need to call pthread_init very early because it is doing signal |
| -- initializations. |
| |
| pthread_init; |
| |
| Abort_Task_Interrupt := SIGADAABORT; |
| |
| act.sa_handler := Notify_Exception'Address; |
| |
| act.sa_flags := 0; |
| |
| -- On some targets, we 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. |
| |
| -- Since SA_NODEFER is obsolete, instead we reset explicitly |
| -- the mask in the exception handler. |
| |
| Result := sigemptyset (Signal_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 := Signal_Mask; |
| |
| Keep_Unmasked (Abort_Task_Interrupt) := True; |
| Keep_Unmasked (SIGXCPU) := True; |
| Keep_Unmasked (SIGFPE) := True; |
| Result := |
| sigaction |
| (Signal (SIGFPE), act'Unchecked_Access, |
| old_act'Unchecked_Access); |
| pragma Assert (Result = 0); |
| |
| -- By keeping SIGINT unmasked, allow the user to do a Ctrl-C, but at |
| -- the same time, disable the ability of handling this signal via |
| -- package Ada.Interrupts. |
| |
| -- The pragma Unreserve_All_Interrupts let the user the ability to |
| -- change this behavior. |
| |
| if Unreserve_All_Interrupts = 0 then |
| Keep_Unmasked (SIGINT) := True; |
| end if; |
| |
| for J in |
| Exception_Interrupts'First + 1 .. Exception_Interrupts'Last |
| loop |
| Keep_Unmasked (Exception_Interrupts (J)) := True; |
| |
| if Unreserve_All_Interrupts = 0 then |
| Result := |
| sigaction |
| (Signal (Exception_Interrupts (J)), act'Unchecked_Access, |
| old_act'Unchecked_Access); |
| pragma Assert (Result = 0); |
| end if; |
| end loop; |
| |
| for J in Unmasked'Range loop |
| Keep_Unmasked (Interrupt_ID (Unmasked (J))) := True; |
| end loop; |
| |
| Reserve := Keep_Unmasked or Keep_Masked; |
| |
| for J in Reserved'Range loop |
| Reserve (Interrupt_ID (Reserved (J))) := True; |
| end loop; |
| |
| -- We do not have Signal 0 in reality. We just use this value |
| -- to identify non-existent 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; |
| end System.Interrupt_Management; |
