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) 1992-2009, 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 3, or (at your option) any later ver- --
14 -- sion. GNAT 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. --
18 -- As a special exception under Section 7 of GPL version 3, you are granted --
19 -- additional permissions described in the GCC Runtime Library Exception, --
20 -- version 3.1, as published by the Free Software Foundation. --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
27 -- GNARL was developed by the GNARL team at Florida State University. --
28 -- Extensive contributions were provided by Ada Core Technologies, Inc. --
30 ------------------------------------------------------------------------------
32 -- This is a Solaris version of this package
34 -- Make a careful study of all signals available under the OS, to see which
35 -- need to be reserved, kept always unmasked, or kept always unmasked.
37 -- Be on the lookout for special signals that may be used by the thread
40 package body System.Interrupt_Management is
43 use System.OS_Interface;
45 type Interrupt_List is array (Interrupt_ID range <>) of Interrupt_ID;
47 Exception_Interrupts : constant Interrupt_List :=
48 (SIGFPE, SIGILL, SIGSEGV, SIGBUS);
50 Unreserve_All_Interrupts : Interfaces.C.int;
52 (C, Unreserve_All_Interrupts, "__gl_unreserve_all_interrupts");
54 function State (Int : Interrupt_ID) return Character;
55 pragma Import (C, State, "__gnat_get_interrupt_state");
56 -- Get interrupt state. Defined in init.c
57 -- The input argument is the interrupt number,
58 -- and the result is one of the following:
60 User : constant Character := 'u';
61 Runtime : constant Character := 'r';
62 Default : constant Character := 's';
63 -- 'n' this interrupt not set by any Interrupt_State pragma
64 -- 'u' Interrupt_State pragma set state to User
65 -- 'r' Interrupt_State pragma set state to Runtime
66 -- 's' Interrupt_State pragma set state to System (use "default"
69 ----------------------
70 -- Notify_Exception --
71 ----------------------
73 -- This function identifies the Ada exception to be raised using the
74 -- information when the system received a synchronous signal. Since this
75 -- function is machine and OS dependent, different code has to be provided
76 -- for different target.
78 procedure Notify_Exception
80 info : access siginfo_t;
81 context : access ucontext_t);
83 ----------------------
84 -- Notify_Exception --
85 ----------------------
87 procedure Notify_Exception
89 info : access siginfo_t;
90 context : access ucontext_t)
93 -- Perform the necessary context adjustments prior to a raise
94 -- from a signal handler.
96 Adjust_Context_For_Raise (signo, context.all'Address);
98 -- Check that treatment of exception propagation here
99 -- is consistent with treatment of the abort signal in
100 -- System.Task_Primitives.Operations.
114 raise Constraint_Error;
117 pragma Assert (False);
121 when SIGILL | SIGSEGV | SIGBUS =>
125 pragma Assert (False);
128 end Notify_Exception;
134 Initialized : Boolean := False;
136 procedure Initialize is
137 act : aliased struct_sigaction;
138 old_act : aliased struct_sigaction;
139 mask : aliased sigset_t;
140 Result : Interfaces.C.int;
149 -- Need to call pthread_init very early because it is doing signal
154 -- Change this if you want to use another signal for task abort.
155 -- SIGTERM might be a good one.
157 Abort_Task_Interrupt := SIGABRT;
159 act.sa_handler := Notify_Exception'Address;
161 -- Set sa_flags to SA_NODEFER so that during the handler execution
162 -- we do not change the Signal_Mask to be masked for the Signal.
163 -- This is a temporary fix to the problem that the Signal_Mask is
164 -- not restored after the exception (longjmp) from the handler.
165 -- The right fix should be made in sigsetjmp so that we save
166 -- the Signal_Set and restore it after a longjmp.
168 -- In that case, this field should be changed back to 0. ??? (Dong-Ik)
172 Result := sigemptyset (mask'Access);
173 pragma Assert (Result = 0);
175 -- ??? For the same reason explained above, we can't mask these signals
176 -- because otherwise we won't be able to catch more than one signal.
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 to
243 -- identify not existing signals (see s-intnam.ads). Therefore, Signal 0
244 -- should not be used in all signal related operations hence mark it as
250 end System.Interrupt_Management;