| ------------------------------------------------------------------------------ |
| -- -- |
| -- 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: 1.15 $ -- |
| -- -- |
| -- 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 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. |
| |
| -- 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. |
| |
| with Interfaces.C; |
| -- used for int |
| |
| with System.Error_Reporting; |
| -- used for Shutdown |
| |
| with System.OS_Interface; |
| -- used for various Constants, Signal and types |
| |
| package body System.Interrupt_Management is |
| |
| use Interfaces.C; |
| use System.Error_Reporting; |
| use System.OS_Interface; |
| |
| type Interrupt_List is array (Interrupt_ID range <>) of Interrupt_ID; |
| Exception_Interrupts : constant Interrupt_List := |
| (SIGFPE, SIGILL, SIGSEGV); |
| |
| Unreserve_All_Interrupts : Interfaces.C.int; |
| pragma Import |
| (C, Unreserve_All_Interrupts, "__gl_unreserve_all_interrupts"); |
| |
| ----------------------- |
| -- Local Subprograms -- |
| ----------------------- |
| |
| procedure Notify_Exception |
| (signo : Signal; |
| info : access siginfo_t; |
| context : access struct_sigcontext); |
| -- 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 -- |
| ---------------------- |
| |
| -- The following code is intended for SunOS on Sparcstation. |
| |
| procedure Notify_Exception |
| (signo : Signal; |
| info : access siginfo_t; |
| context : access struct_sigcontext) |
| is |
| begin |
| -- As long as we are using a longjmp to return control to the |
| -- exception handler on the runtime stack, we are safe. The original |
| -- signal mask (the one we had before coming into this signal catching |
| -- function) will be restored by the longjmp. Therefore, raising |
| -- an exception in this handler should be a safe operation. |
| |
| -- 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_INTOVF_TRAP | |
| FPE_STARTSIG_TRAP | |
| FPE_INTDIV_TRAP | |
| FPE_FLTDIV_TRAP | |
| FPE_FLTUND_TRAP | |
| FPE_FLTOPERR_TRAP | |
| FPE_FLTOVF_TRAP => |
| raise Constraint_Error; |
| |
| when others => |
| pragma Assert (Shutdown ("Unexpected SIGFPE signal")); |
| null; |
| end case; |
| |
| when SIGILL => |
| case info.si_code is |
| when ILL_STACK | |
| ILL_ILLINSTR_FAULT | |
| ILL_PRIVINSTR_FAULT => |
| raise Constraint_Error; |
| |
| when others => |
| pragma Assert (Shutdown ("Unexpected SIGILL signal")); |
| null; |
| end case; |
| |
| when SIGSEGV => |
| |
| -- was caused by accessing a null pointer. |
| |
| -- ???? Origin of this code is unclear, may be broken ??? |
| |
| if context.sc_o0 in 0 .. 16#2000# then |
| raise Constraint_Error; |
| else |
| raise Storage_Error; |
| end if; |
| |
| when others => |
| pragma Assert (Shutdown ("Unexpected signal")); |
| 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; |
| mask : aliased sigset_t; |
| Result : Interfaces.C.int; |
| |
| begin |
| -- Need to call pthread_init very early because it is doing signal |
| -- initializations. |
| |
| pthread_init; |
| |
| -- Change the following assignment to use another signal for task abort. |
| -- For example, SIGTERM might be a good one if SIGABRT is required for |
| -- use elsewhere. |
| |
| 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. ??? |
| |
| act.sa_flags := 16; |
| |
| Result := sigemptyset (mask'Access); |
| pragma Assert (Result = 0); |
| |
| for J in Exception_Interrupts'Range loop |
| Result := sigaddset (mask'Access, Signal (Exception_Interrupts (J))); |
| pragma Assert (Result = 0); |
| end loop; |
| |
| act.sa_mask := mask; |
| |
| for J in Exception_Interrupts'Range 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; |
| |
| Keep_Unmasked (Abort_Task_Interrupt) := True; |
| Keep_Unmasked (SIGBUS) := True; |
| Keep_Unmasked (SIGFPE) := True; |
| Result := |
| sigaction |
| (Signal (SIGFPE), act'Unchecked_Access, |
| old_act'Unchecked_Access); |
| |
| Keep_Unmasked (SIGALRM) := True; |
| Keep_Unmasked (SIGSTOP) := True; |
| Keep_Unmasked (SIGKILL) := True; |
| Keep_Unmasked (SIGXCPU) := True; |
| |
| -- By keeping SIGINT unmasked, allow the user to do a Ctrl-C, but at |
| -- the same time, disable the ability of handling this signal using |
| -- package Ada.Interrupts. |
| |
| -- The pragma Unreserve_All_Interrupts allows the user the ability to |
| -- change this behavior. |
| |
| if Unreserve_All_Interrupts = 0 then |
| Keep_Unmasked (SIGINT) := True; |
| end if; |
| |
| -- Reserve this not to interfere with thread scheduling |
| |
| -- ??? consider adding this to interrupt exceptions |
| -- Keep_Unmasked (SIGALRM) := True; |
| |
| -- An earlier version had a comment about SIGALRM needing to be unmasked |
| -- in at least one thread for cond_timedwait to work. |
| |
| -- It is unclear whether this is True for Solaris threads, FSU threads, |
| -- both, or maybe just an old version of FSU threads. ???? |
| |
| -- Following signals should not be disturbed. Found by experiment |
| |
| Keep_Unmasked (SIGEMT) := True; |
| Keep_Unmasked (SIGCHLD) := True; |
| |
| -- 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 := Reserve or Keep_Unmasked or Keep_Masked; |
| Reserve (0) := True; |
| end; |
| end System.Interrupt_Management; |
