1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS --
5 -- 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 --
9 -- Copyright (C) 1992-2007, Free Software Foundation, Inc. --
11 -- GNARL is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 2, or (at your option) any later ver- --
14 -- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNARL; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- As a special exception, if other files instantiate generics from this --
23 -- unit, or you link this unit with other files to produce an executable, --
24 -- this unit does not by itself cause the resulting executable to be --
25 -- covered by the GNU General Public License. This exception does not --
26 -- however invalidate any other reasons why the executable file might be --
27 -- covered by the GNU Public License. --
29 -- GNARL was developed by the GNARL team at Florida State University. --
30 -- Extensive contributions were provided by Ada Core Technologies, Inc. --
32 ------------------------------------------------------------------------------
34 -- This is a Solaris version of this package
36 -- Make a careful study of all signals available under the OS, to see which
37 -- need to be reserved, kept always unmasked, or kept always unmasked.
39 -- Be on the lookout for special signals that may be used by the thread
42 package body System.Interrupt_Management is
45 use System.OS_Interface;
47 type Interrupt_List is array (Interrupt_ID range <>) of Interrupt_ID;
49 Exception_Interrupts : constant Interrupt_List :=
50 (SIGFPE, SIGILL, SIGSEGV, SIGBUS);
52 Unreserve_All_Interrupts : Interfaces.C.int;
54 (C, Unreserve_All_Interrupts, "__gl_unreserve_all_interrupts");
56 function State (Int : Interrupt_ID) return Character;
57 pragma Import (C, State, "__gnat_get_interrupt_state");
58 -- Get interrupt state. Defined in init.c
59 -- The input argument is the interrupt number,
60 -- and the result is one of the following:
62 User : constant Character := 'u';
63 Runtime : constant Character := 'r';
64 Default : constant Character := 's';
65 -- 'n' this interrupt not set by any Interrupt_State pragma
66 -- 'u' Interrupt_State pragma set state to User
67 -- 'r' Interrupt_State pragma set state to Runtime
68 -- 's' Interrupt_State pragma set state to System (use "default"
71 ----------------------
72 -- Notify_Exception --
73 ----------------------
75 -- This function identifies the Ada exception to be raised using the
76 -- information when the system received a synchronous signal. Since this
77 -- function is machine and OS dependent, different code has to be provided
78 -- for different target.
80 procedure Notify_Exception
82 info : access siginfo_t;
83 context : access ucontext_t);
85 ----------------------
86 -- Notify_Exception --
87 ----------------------
89 procedure Notify_Exception
91 info : access siginfo_t;
92 context : access ucontext_t)
95 -- Perform the necessary context adjustments prior to a raise
96 -- from a signal handler.
98 Adjust_Context_For_Raise (signo, context.all'Address);
100 -- Check that treatment of exception propagation here
101 -- is consistent with treatment of the abort signal in
102 -- System.Task_Primitives.Operations.
116 raise Constraint_Error;
119 pragma Assert (False);
123 when SIGILL | SIGSEGV | SIGBUS =>
127 pragma Assert (False);
130 end Notify_Exception;
136 Initialized : Boolean := False;
138 procedure Initialize is
139 act : aliased struct_sigaction;
140 old_act : aliased struct_sigaction;
141 mask : aliased sigset_t;
142 Result : Interfaces.C.int;
151 -- Need to call pthread_init very early because it is doing signal
156 -- Change this if you want to use another signal for task abort.
157 -- SIGTERM might be a good one.
159 Abort_Task_Interrupt := SIGABRT;
161 act.sa_handler := Notify_Exception'Address;
163 -- Set sa_flags to SA_NODEFER so that during the handler execution
164 -- we do not change the Signal_Mask to be masked for the Signal.
165 -- This is a temporary fix to the problem that the Signal_Mask is
166 -- not restored after the exception (longjmp) from the handler.
167 -- The right fix should be made in sigsetjmp so that we save
168 -- the Signal_Set and restore it after a longjmp.
170 -- In that case, this field should be changed back to 0. ??? (Dong-Ik)
174 Result := sigemptyset (mask'Access);
175 pragma Assert (Result = 0);
177 -- ??? For the same reason explained above, we can't mask these signals
178 -- because otherwise we won't be able to catch more than one signal.
182 pragma Assert (Keep_Unmasked = (Interrupt_ID'Range => False));
183 pragma Assert (Reserve = (Interrupt_ID'Range => False));
185 for J in Exception_Interrupts'Range loop
186 if State (Exception_Interrupts (J)) /= User then
187 Keep_Unmasked (Exception_Interrupts (J)) := True;
188 Reserve (Exception_Interrupts (J)) := True;
190 if State (Exception_Interrupts (J)) /= Default then
193 (Signal (Exception_Interrupts (J)), act'Unchecked_Access,
194 old_act'Unchecked_Access);
195 pragma Assert (Result = 0);
200 if State (Abort_Task_Interrupt) /= User then
201 Keep_Unmasked (Abort_Task_Interrupt) := True;
202 Reserve (Abort_Task_Interrupt) := True;
205 -- Set SIGINT to unmasked state as long as it's
206 -- not in "User" state. Check for Unreserve_All_Interrupts last
208 if State (SIGINT) /= User then
209 Keep_Unmasked (SIGINT) := True;
210 Reserve (SIGINT) := True;
213 -- Check all signals for state that requires keeping them
214 -- unmasked and reserved
216 for J in Interrupt_ID'Range loop
217 if State (J) = Default or else State (J) = Runtime then
218 Keep_Unmasked (J) := True;
223 -- Add the set of signals that must always be unmasked for this target
225 for J in Unmasked'Range loop
226 Keep_Unmasked (Interrupt_ID (Unmasked (J))) := True;
227 Reserve (Interrupt_ID (Unmasked (J))) := True;
230 -- Add target-specific reserved signals
232 for J in Reserved'Range loop
233 Reserve (Interrupt_ID (Reserved (J))) := True;
236 -- Process pragma Unreserve_All_Interrupts. This overrides any
237 -- settings due to pragma Interrupt_State:
239 if Unreserve_All_Interrupts /= 0 then
240 Keep_Unmasked (SIGINT) := False;
241 Reserve (SIGINT) := False;
244 -- We do not have Signal 0 in reality. We just use this value to
245 -- identify not existing signals (see s-intnam.ads). Therefore, Signal 0
246 -- should not be used in all signal related operations hence mark it as
252 end System.Interrupt_Management;