1 ------------------------------------------------------------------------------
3 -- GNU ADA 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) 1992-2004 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, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, 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 the VxWorks version of this package.
36 -- It is likely to need tailoring to fit each operating system
37 -- and machine architecture.
39 -- PLEASE DO NOT add any dependences on other packages.
40 -- This package is designed to work with or without tasking support.
42 -- See the other warnings in the package specification before making
43 -- any modifications to this file.
45 -- Make a careful study of all signals available under the OS,
46 -- to see which need to be reserved, kept always unmasked,
47 -- or kept always unmasked.
48 -- Be on the lookout for special signals that
49 -- may be used by the thread library.
53 with System.OS_Interface;
54 -- used for various Constants, Signal and types
56 package body System.Interrupt_Management is
58 use System.OS_Interface;
59 use type Interfaces.C.int;
61 type Signal_List is array (Signal_ID range <>) of Signal_ID;
62 Exception_Signals : constant Signal_List (1 .. 4) :=
63 (SIGFPE, SIGILL, SIGSEGV, SIGBUS);
65 -- Keep these variables global so that they are initialized only once
66 -- What are "these variables" ???, I see only one
68 Exception_Action : aliased struct_sigaction;
70 procedure Map_And_Raise_Exception (signo : Signal);
71 pragma Import (C, Map_And_Raise_Exception, "__gnat_map_signal");
72 -- Map signal to Ada exception and raise it. Different versions
73 -- of VxWorks need different mappings.
75 -----------------------
76 -- Local Subprograms --
77 -----------------------
79 procedure Notify_Exception (signo : Signal);
80 -- Identify the Ada exception to be raised using
81 -- the information when the system received a synchronous signal.
83 ----------------------
84 -- Notify_Exception --
85 ----------------------
87 procedure Notify_Exception (signo : Signal) is
88 Mask : aliased sigset_t;
92 pragma Unreferenced (Result);
95 Result := pthread_sigmask (SIG_SETMASK, null, Mask'Unchecked_Access);
96 Result := sigdelset (Mask'Access, signo);
97 Result := pthread_sigmask (SIG_SETMASK, Mask'Unchecked_Access, null);
99 -- VxWorks will suspend the task when it gets a hardware
100 -- exception. We take the liberty of resuming the task
101 -- for the application.
105 if taskIsSuspended (My_Id) /= 0 then
106 Result := taskResume (My_Id);
109 Map_And_Raise_Exception (signo);
110 end Notify_Exception;
112 ---------------------------
113 -- Initialize_Interrupts --
114 ---------------------------
116 -- Since there is no signal inheritance between VxWorks tasks, we need
117 -- to initialize signal handling in each task.
119 procedure Initialize_Interrupts is
121 old_act : aliased struct_sigaction;
124 for J in Exception_Signals'Range loop
127 (Signal (Exception_Signals (J)), Exception_Action'Access,
128 old_act'Unchecked_Access);
129 pragma Assert (Result = 0);
131 end Initialize_Interrupts;
135 mask : aliased sigset_t;
138 function State (Int : Interrupt_ID) return Character;
139 pragma Import (C, State, "__gnat_get_interrupt_state");
140 -- Get interrupt state. Defined in a-init.c
141 -- The input argument is the interrupt number,
142 -- and the result is one of the following:
144 Runtime : constant Character := 'r';
145 Default : constant Character := 's';
146 -- 'n' this interrupt not set by any Interrupt_State pragma
147 -- 'u' Interrupt_State pragma set state to User
148 -- 'r' Interrupt_State pragma set state to Runtime
149 -- 's' Interrupt_State pragma set state to System (use "default"
153 -- Initialize signal handling
155 -- Change this if you want to use another signal for task abort.
156 -- SIGTERM might be a good one.
158 Abort_Task_Signal := SIGABRT;
160 Exception_Action.sa_handler := Notify_Exception'Address;
161 Exception_Action.sa_flags := SA_ONSTACK;
162 Result := sigemptyset (mask'Access);
163 pragma Assert (Result = 0);
165 for J in Exception_Signals'Range loop
166 Result := sigaddset (mask'Access, Signal (Exception_Signals (J)));
167 pragma Assert (Result = 0);
170 Exception_Action.sa_mask := mask;
172 -- Initialize hardware interrupt handling
174 pragma Assert (Reserve = (Interrupt_ID'Range => False));
176 -- Check all interrupts for state that requires keeping them reserved
178 for J in Interrupt_ID'Range loop
179 if State (J) = Default or else State (J) = Runtime then
184 -- Add exception signals to the set of unmasked signals
186 for J in Exception_Signals'Range loop
187 Keep_Unmasked (Exception_Signals (J)) := True;
190 -- The abort signal must also be unmasked
192 Keep_Unmasked (Abort_Task_Signal) := True;
194 end System.Interrupt_Management;