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) 1992-2006 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,
37 -- to see which need to be reserved, kept always unmasked,
38 -- or kept always unmasked.
40 -- Be on the lookout for special signals that
41 -- may be used by the thread library.
43 package body System.Interrupt_Management is
46 use System.OS_Interface;
48 type Interrupt_List is array (Interrupt_ID range <>) of Interrupt_ID;
50 Exception_Interrupts : constant Interrupt_List :=
51 (SIGFPE, SIGILL, SIGSEGV, SIGBUS);
53 Unreserve_All_Interrupts : Interfaces.C.int;
55 (C, Unreserve_All_Interrupts, "__gl_unreserve_all_interrupts");
57 function State (Int : Interrupt_ID) return Character;
58 pragma Import (C, State, "__gnat_get_interrupt_state");
59 -- Get interrupt state. Defined in init.c
60 -- The input argument is the interrupt number,
61 -- and the result is one of the following:
63 User : constant Character := 'u';
64 Runtime : constant Character := 'r';
65 Default : constant Character := 's';
66 -- 'n' this interrupt not set by any Interrupt_State pragma
67 -- 'u' Interrupt_State pragma set state to User
68 -- 'r' Interrupt_State pragma set state to Runtime
69 -- 's' Interrupt_State pragma set state to System (use "default"
72 ----------------------
73 -- Notify_Exception --
74 ----------------------
76 -- This function identifies the Ada exception to be raised using
77 -- the information when the system received a synchronous signal.
78 -- Since this function is machine and OS dependent, different code
79 -- has to be provided for different target.
81 procedure Notify_Exception
83 info : access siginfo_t;
84 context : access ucontext_t);
86 ----------------------
87 -- Notify_Exception --
88 ----------------------
90 procedure Notify_Exception
92 info : access siginfo_t;
93 context : access ucontext_t)
95 pragma Unreferenced (context);
97 -- Check that treatment of exception propagation here
98 -- is consistent with treatment of the abort signal in
99 -- System.Task_Primitives.Operations.
113 raise Constraint_Error;
116 pragma Assert (False);
120 when SIGILL | SIGSEGV | SIGBUS =>
124 pragma Assert (False);
127 end Notify_Exception;
133 Initialized : Boolean := False;
135 procedure Initialize is
136 act : aliased struct_sigaction;
137 old_act : aliased struct_sigaction;
138 mask : aliased sigset_t;
139 Result : Interfaces.C.int;
148 -- Need to call pthread_init very early because it is doing signal
153 -- Change this if you want to use another signal for task abort.
154 -- SIGTERM might be a good one.
156 Abort_Task_Interrupt := SIGABRT;
158 act.sa_handler := Notify_Exception'Address;
160 -- Set sa_flags to SA_NODEFER so that during the handler execution
161 -- we do not change the Signal_Mask to be masked for the Signal.
162 -- This is a temporary fix to the problem that the Signal_Mask is
163 -- not restored after the exception (longjmp) from the handler.
164 -- The right fix should be made in sigsetjmp so that we save
165 -- the Signal_Set and restore it after a longjmp.
167 -- In that case, this field should be changed back to 0. ??? (Dong-Ik)
171 Result := sigemptyset (mask'Access);
172 pragma Assert (Result = 0);
174 -- ??? For the same reason explained above, we can't mask these
175 -- signals because otherwise we won't be able to catch more than
180 pragma Assert (Keep_Unmasked = (Interrupt_ID'Range => False));
181 pragma Assert (Reserve = (Interrupt_ID'Range => False));
183 for J in Exception_Interrupts'Range loop
184 if State (Exception_Interrupts (J)) /= User then
185 Keep_Unmasked (Exception_Interrupts (J)) := True;
186 Reserve (Exception_Interrupts (J)) := True;
188 if State (Exception_Interrupts (J)) /= Default then
191 (Signal (Exception_Interrupts (J)), act'Unchecked_Access,
192 old_act'Unchecked_Access);
193 pragma Assert (Result = 0);
198 if State (Abort_Task_Interrupt) /= User then
199 Keep_Unmasked (Abort_Task_Interrupt) := True;
200 Reserve (Abort_Task_Interrupt) := True;
203 -- Set SIGINT to unmasked state as long as it's
204 -- not in "User" state. Check for Unreserve_All_Interrupts last
206 if State (SIGINT) /= User then
207 Keep_Unmasked (SIGINT) := True;
208 Reserve (SIGINT) := True;
211 -- Check all signals for state that requires keeping them
212 -- unmasked and reserved
214 for J in Interrupt_ID'Range loop
215 if State (J) = Default or else State (J) = Runtime then
216 Keep_Unmasked (J) := True;
221 -- Add the set of signals that must always be unmasked for this target
223 for J in Unmasked'Range loop
224 Keep_Unmasked (Interrupt_ID (Unmasked (J))) := True;
225 Reserve (Interrupt_ID (Unmasked (J))) := True;
228 -- Add target-specific reserved signals
230 for J in Reserved'Range loop
231 Reserve (Interrupt_ID (Reserved (J))) := True;
234 -- Process pragma Unreserve_All_Interrupts. This overrides any
235 -- settings due to pragma Interrupt_State:
237 if Unreserve_All_Interrupts /= 0 then
238 Keep_Unmasked (SIGINT) := False;
239 Reserve (SIGINT) := False;
242 -- We do not have Signal 0 in reality. We just use this value
243 -- to identify not existing signals (see s-intnam.ads). Therefore,
244 -- Signal 0 should not be used in all signal related operations hence
245 -- mark it as reserved.
250 end System.Interrupt_Management;