| ------------------------------------------------------------------------------ |
| -- -- |
| -- 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: 1.2 $ |
| -- -- |
| -- 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 GNU/Linux version of this package |
| |
| -- This file performs the system-dependent translation between machine |
| -- exceptions and the Ada exceptions, if any, that should be raised when they |
| -- occur. This version works for the x86 running linux. |
| |
| -- 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. |
| |
| -- The definitions of "reserved" differ slightly between the ARM and POSIX. |
| -- Here is the ARM definition of reserved interrupt: |
| |
| -- The set of reserved interrupts is implementation defined. A reserved |
| -- interrupt is either an interrupt for which user-defined handlers are not |
| -- supported, or one which already has an attached handler by some other |
| -- implementation-defined means. Program units can be connected to |
| -- non-reserved interrupts. |
| |
| -- POSIX.5b/.5c specifies further: |
| |
| -- Signals which the application cannot accept, and for which the application |
| -- cannot modify the signal action or masking, because the signals are |
| -- reserved for use by the Ada language implementation. The reserved signals |
| -- defined by this standard are Signal_Abort, Signal_Alarm, |
| -- Signal_Floating_Point_Error, Signal_Illegal_Instruction, |
| -- Signal_Segmentation_Violation, Signal_Bus_Error. If the implementation |
| -- supports any signals besides those defined by this standard, the |
| -- implementation may also reserve some of those. |
| |
| -- The signals defined by POSIX.5b/.5c that are not specified as being |
| -- reserved are SIGHUP, SIGINT, SIGPIPE, SIGQUIT, SIGTERM, SIGUSR1, SIGUSR2, |
| -- SIGCHLD, SIGCONT, SIGSTOP, SIGTSTP, SIGTTIN, SIGTTOU, SIGIO SIGURG, and all |
| -- the real-time signals. |
| |
| -- Beware of reserving signals that POSIX.5b/.5c require to be available for |
| -- users. POSIX.5b/.5c say: |
| |
| -- An implementation shall not impose restrictions on the ability of an |
| -- application to send, accept, block, or ignore the signals defined by this |
| -- standard, except as specified in this standard. |
| |
| -- Here are some other relevant requirements from POSIX.5b/.5c: |
| |
| -- For the environment task, the initial signal mask is that specified for |
| -- the process... |
| |
| -- It is anticipated that the paragraph above may be modified by a future |
| -- revision of this standard, to require that the realtime signals always be |
| -- initially masked for a process that is an Ada active partition. |
| |
| -- For all other tasks, the initial signal mask shall include all the signals |
| -- that are not reserved signals and are not bound to entries of the task. |
| |
| with Interfaces.C; |
| -- used for int and other types |
| |
| with System.Error_Reporting; |
| -- used for Shutdown |
| |
| with System.OS_Interface; |
| -- used for various Constants, Signal and types |
| |
| with Ada.Exceptions; |
| -- used for Exception_Id |
| -- Raise_From_Signal_Handler |
| |
| with System.Soft_Links; |
| -- used for Get_Machine_State_Addr |
| |
| with Unchecked_Conversion; |
| |
| package body System.Interrupt_Management is |
| |
| use Interfaces.C; |
| use System.Error_Reporting; |
| use System.OS_Interface; |
| |
| package TSL renames System.Soft_Links; |
| |
| 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"); |
| |
| subtype int is Interfaces.C.int; |
| subtype unsigned_short is Interfaces.C.unsigned_short; |
| subtype unsigned_long is Interfaces.C.unsigned_long; |
| |
| ---------------------- |
| -- Notify_Exception -- |
| ---------------------- |
| |
| Signal_Mask : aliased sigset_t; |
| -- The set of signals handled by 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; |
| gs : unsigned_short; |
| fs : unsigned_short; |
| es : unsigned_short; |
| ds : unsigned_short; |
| edi : unsigned_long; |
| esi : unsigned_long; |
| ebp : unsigned_long; |
| esp : unsigned_long; |
| ebx : unsigned_long; |
| edx : unsigned_long; |
| ecx : unsigned_long; |
| eax : unsigned_long; |
| trapno : unsigned_long; |
| err : unsigned_long; |
| eip : unsigned_long; |
| cs : unsigned_short; |
| eflags : unsigned_long; |
| esp_at_signal : unsigned_long; |
| ss : unsigned_short; |
| fpstate : System.Address; |
| oldmask : unsigned_long; |
| cr2 : unsigned_long); |
| |
| procedure Notify_Exception |
| (signo : Signal; |
| gs : unsigned_short; |
| fs : unsigned_short; |
| es : unsigned_short; |
| ds : unsigned_short; |
| edi : unsigned_long; |
| esi : unsigned_long; |
| ebp : unsigned_long; |
| esp : unsigned_long; |
| ebx : unsigned_long; |
| edx : unsigned_long; |
| ecx : unsigned_long; |
| eax : unsigned_long; |
| trapno : unsigned_long; |
| err : unsigned_long; |
| eip : unsigned_long; |
| cs : unsigned_short; |
| eflags : unsigned_long; |
| esp_at_signal : unsigned_long; |
| ss : unsigned_short; |
| fpstate : System.Address; |
| oldmask : unsigned_long; |
| cr2 : unsigned_long) |
| is |
| |
| function To_Machine_State_Ptr is new |
| Unchecked_Conversion (Address, Machine_State_Ptr); |
| |
| -- These are not directly visible |
| |
| procedure Raise_From_Signal_Handler |
| (E : Ada.Exceptions.Exception_Id; |
| M : System.Address); |
| pragma Import |
| (Ada, Raise_From_Signal_Handler, |
| "ada__exceptions__raise_from_signal_handler"); |
| pragma No_Return (Raise_From_Signal_Handler); |
| |
| mstate : Machine_State_Ptr; |
| message : aliased constant String := "" & ASCII.Nul; |
| -- a null terminated String. |
| |
| Result : int; |
| |
| begin |
| |
| -- Raise_From_Signal_Handler makes sure that the exception is raised |
| -- safely from this signal handler. |
| |
| -- ??? The original signal mask (the one we had before coming into this |
| -- signal catching function) should be restored by |
| -- Raise_From_Signal_Handler. For now, 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. |
| |
| mstate := To_Machine_State_Ptr (TSL.Get_Machine_State_Addr.all); |
| mstate.eip := eip; |
| mstate.ebx := ebx; |
| mstate.esp := esp_at_signal; |
| mstate.ebp := ebp; |
| mstate.esi := esi; |
| mstate.edi := edi; |
| |
| case signo is |
| when SIGFPE => |
| Raise_From_Signal_Handler |
| (Constraint_Error'Identity, message'Address); |
| when SIGILL => |
| Raise_From_Signal_Handler |
| (Constraint_Error'Identity, message'Address); |
| when SIGSEGV => |
| Raise_From_Signal_Handler |
| (Storage_Error'Identity, message'Address); |
| when others => |
| if Shutdown ("Unexpected signal") then |
| null; |
| end if; |
| end case; |
| end Notify_Exception; |
| |
| --------------------------- |
| -- Initialize_Interrupts -- |
| --------------------------- |
| |
| -- Nothing needs to be done on this platform. |
| |
| procedure Initialize_Interrupts is |
| begin |
| null; |
| end Initialize_Interrupts; |
| |
| begin |
| declare |
| act : aliased struct_sigaction; |
| old_act : aliased struct_sigaction; |
| Result : 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 J in Exception_Interrupts'Range loop |
| Result := |
| sigaddset (Signal_Mask'Access, Signal (Exception_Interrupts (J))); |
| pragma Assert (Result = 0); |
| end loop; |
| |
| act.sa_mask := Signal_Mask; |
| |
| Result := |
| sigaction |
| (Signal (SIGFPE), act'Unchecked_Access, |
| old_act'Unchecked_Access); |
| pragma Assert (Result = 0); |
| |
| 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; |
| |
| Keep_Unmasked (Abort_Task_Interrupt) := True; |
| Keep_Unmasked (SIGXCPU) := True; |
| Keep_Unmasked (SIGBUS) := True; |
| Keep_Unmasked (SIGFPE) := True; |
| |
| -- By keeping SIGINT unmasked, allow the user to do a Ctrl-C, but in the |
| -- same time, disable the ability of handling this signal |
| -- via 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 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; |
| |
| Reserve (0) := True; |
| -- 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. |
| |
| end; |
| end System.Interrupt_Management; |