# See the License for the specific language governing permissions and
# limitations under the License.
-# Module to manage standard C signals
+# ANSI C signal handling
#
# Common usage imply 5 steps:
#
#define _POSIX_SOURCE 1
#include <signal.h>
#include <stdio.h>
+ #include <unistd.h>
/*
- This guard prevents errors by the C compiler when the Nit code imports this
- module but do not use handle_signal. When it is _not_ used, the C type
- SignalHandler and C function SignalHandler_receive_signal are not generated.
- Which does not please the C compiler. This guard ensure that we compile this
- code only if the type SignalHandler has been defined.
-
- This is a HACK, FIXME by:
- * Adding the macro to the FFI spec, or
- * Attach the callbacks to this code block (or the module itself)
- * Avoid using Nit types and callbacks or use them only in the C implementation
- of Nit method.
*/
- #ifdef NIT_TYPE_SignalHandler
+ void (*nit_SignalHandler_receive_signal)(void* self, long signal);
/*
Structure to manage each possible signals
*/
struct nit_signals_ent {
char raised; /* !=0 if has been raised */
- SignalHandler handler; /* instance to receive call */
+ void* handler; /* instance to receive call */
char safely; /* if !=0 then manage signal safely, otherwise react when raised */
- } nit_signals_list[32] = {0x0};
+ } nit_signals_list[32] = {{0}};
/* Receiver to all signals
If unsafe, it calls directly the Nit receiver,
if (nit_signals_list[sig].safely) {
nit_signals_list[sig].raised += 1;
} else {
- SignalHandler_receive_signal(nit_signals_list[sig].handler, sig);
+ nit_SignalHandler_receive_signal(nit_signals_list[sig].handler, sig);
}
}
}
-
- #endif
`}
# Receives the callback from system when a given signal arise
#
# class MyReceiver
# super SignalHandler
- #
+ #
# redef fun receive_signal(signal) do print "received safely {signal}"
# end
- #
+ #
# var r = new MyReceiver
# r.handle_signal(sigint, true) # will call back when "check_signals" is called
# # ...
#
# class MyReceiver
# super SignalHandler
- #
+ #
# redef fun receive_signal_unsafe(signal) do print "received unsafely {signal}"
# end
- #
+ #
# var r = new MyReceiver
# r.handle_signal(sigsegv, false) # `r.receive_signal_unsafe` will be invoked on sigsegv
fun receive_signal_unsafe(signal: Int) do end
# If `safely`, receiver will be called when `check_signals` in invoked
# otherwise the receiver is invoked when the signal is raised, it may
# crash the Nit system but is unavoidable for unstoppable signals.
- fun handle_signal(signal: Int, safely: Bool) import
- receive_signal `{
- SignalHandler last_handler;
+ fun handle_signal(signal: Int, safely: Bool) import receive_signal `{
if (signal < 32 && signal >=0) {
struct sigaction act;
sigemptyset(&act.sa_mask);
sigaction(signal, &act, NULL);
- last_handler = nit_signals_list[signal].handler;
+ #ifdef SignalHandler_decr_ref
+ SignalHandler last_handler = (SignalHandler)nit_signals_list[signal].handler;
if (last_handler != NULL)
SignalHandler_decr_ref(last_handler);
+ #endif
nit_signals_list[signal].handler = self;
+
+ #ifdef SignalHandler_incr_ref
SignalHandler_incr_ref(self);
+ #endif
nit_signals_list[signal].safely = safely;
+
+ nit_SignalHandler_receive_signal = SignalHandler_receive_signal;
}
`}
# Set to ignore the signal
fun ignore_signal(signal: Int) `{
- SignalHandler last_handler;
if (signal < 32 && signal >=0) {
struct sigaction act;
sigemptyset(&act.sa_mask);
act.sa_handler = SIG_IGN;
sigaction(signal, &act, NULL);
- last_handler = nit_signals_list[signal].handler;
+ #ifdef SignalHandler_decr_ref
+ SignalHandler last_handler = (SignalHandler)nit_signals_list[signal].handler;
if (last_handler != NULL)
SignalHandler_decr_ref(last_handler);
+ #endif
}
`}
# Set default action for the signal
fun default_signal(signal: Int) `{
- SignalHandler last_handler;
if (signal < 32 && signal >=0) {
struct sigaction act;
sigemptyset(&act.sa_mask);
act.sa_handler = SIG_DFL;
sigaction(signal, &act, NULL);
- last_handler = nit_signals_list[signal].handler;
+ #ifdef SignalHandler_decr_ref
+ SignalHandler last_handler = (SignalHandler)nit_signals_list[signal].handler;
if (last_handler != NULL)
SignalHandler_decr_ref(last_handler);
+ #endif
}
`}
end
-redef interface Object
-
- # Check signals for safe operation
- # will callback receiver of raised signals
- # can callback any instance of SignalHandler, not just this one
- protected fun check_signals: Bool is extern import SignalHandler.receive_signal `{
- int sig;
- int raised_something = 0;
-
- for (sig = 0; sig < 32; sig ++)
- if (nit_signals_list[sig].raised) {
- nit_signals_list[sig].raised = 0;
- raised_something = 1;
- SignalHandler_receive_signal(nit_signals_list[sig].handler, sig);
- }
+# Check signals for safe operation
+# will callback receiver of raised signals
+# can callback any instance of SignalHandler, not just this one
+fun check_signals: Bool is extern import SignalHandler.receive_signal `{
+ int sig;
+ int raised_something = 0;
+
+ for (sig = 0; sig < 32; sig ++)
+ if (nit_signals_list[sig].raised) {
+ nit_signals_list[sig].raised = 0;
+ raised_something = 1;
+ SignalHandler handler = (SignalHandler)nit_signals_list[sig].handler;
+ SignalHandler_receive_signal(handler, sig);
+ }
- return raised_something;
- `}
+ return raised_something;
+`}
- # Set alarm signal
- # can callback any instance of SignalHandler, not just this one
- protected fun set_alarm(sec: Int) `{ alarm(sec); `}
-end
+# Set alarm signal
+# can callback any instance of SignalHandler, not just this one
+fun set_alarm(sec: Int) `{ alarm(sec); `}
redef class Process
# Send a signal to the process
# Send the kill signal to the process
fun kill do signal(sigkill)
-
+
# Native implementation of `signal`
private fun native_kill(pid, signal: Int) `{ kill(pid, signal); `}
end
# Profiling timer expired
fun sigprof: Int do return 27
-# Sent to a process when its controlling terminal changes its window size
+# Sent to a process when its controlling terminal changes its window size
fun sigwinch: Int do return 28
# Sent to a process when the system experiences a power failure
nitlanguage / nit.git / blobdiff