# limitations under the License.
# Module to manage standard C signals
+#
+# Common usage imply 5 steps:
+#
+# 1. Implement the `SignalHandler` interface
+# 2. `redef receive_signal_unsafe` to handle `sigsegv`
+# 3. `redef receive_signal` to handle other signals safely
+# 4, Notify what signals to handle with `handle_signal`
+# 5. If using the safe handler method, routinely call `check_signals`
+#
+# Usage example:
+#
+# ~~~~
+# class MyReceiver
+# super SignalHandler
+#
+# redef fun receive_signal(signal)
+# do
+# print "received safely {signal}"
+# if signal == sigalarm then print "Alarm!"
+# end
+# redef fun receive_signal_unsafe( signal ) do print "received unsafely {signal}"
+# end
+#
+# var r = new MyReceiver
+#
+# # Handle `sigsegv` signal unsafely (the only way for this one)
+# r.handle_signal(sigsegv, false)
+#
+# # Handle `sigint` and `sigalarm` safely
+# r.handle_signal(sigint, true)
+# r.handle_signal(sigalarm, true)
+#
+# # Ask system to receive a `sigalarm` signal in 1 second
+# set_alarm(1)
+#
+# loop
+# # Check signals and callback `receive_signal`
+# var hit = check_signals
+#
+# if hit then break
+# end
+# ~~~~
module signals
`{
#include <stdio.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
+
+ /*
Structure to manage each possible signals
are used in an array of 32 maximum signals.
This array is global to the software.
}
}
}
+
+ #endif
`}
# Receives the callback from system when a given signal arise
# r.handle_signal(sigint, true) # will call back when "check_signals" is called
# # ...
# check_signals # if a signal was received, it will invoke `r.receive_signal`
- fun receive_signal(signal: Int) `{
- `}
+ fun receive_signal(signal: Int) do end
# Called immediatly on receiving an unsafe signal (should be redefed by subclasses)
#
#
# var r = new MyReceiver
# r.handle_signal(sigsegv, false) # `r.receive_signal_unsafe` will be invoked on sigsegv
- fun receive_signal_unsafe(signal: Int) `{
- `}
+ fun receive_signal_unsafe(signal: Int) do end
# Set the receiver as the handler of the signal
#
end
# Hang up detected on controlling terminal or death of controlling process
-protected fun sighup: Int do return 1
+fun sighup: Int do return 1
# Issued if the user sends an interrupt signal
-protected fun sigint: Int do return 2
+fun sigint: Int do return 2
# Issued if the user sends a quit signal
-protected fun sigquit: Int do return 3
+fun sigquit: Int do return 3
# Issued if the user attempts to execute an illegal, malformed, unknown, or privileged instruction
-protected fun sigill: Int do return 4
+fun sigill: Int do return 4
# Issued when an exception occurs: a condition that a debugger has requested to be informed of
-protected fun sigtrap: Int do return 5
+fun sigtrap: Int do return 5
# This signal is sent to a process to tell it to abort, i. e. to terminate
-protected fun sigabrt: Int do return 6
+fun sigabrt: Int do return 6
# This signal is sent to a process when it causes a bus error
-protected fun sigbus: Int do return 7
+fun sigbus: Int do return 7
# Issued if an illegal mathematical operation is attempted
-protected fun sigfpe: Int do return 8
+fun sigfpe: Int do return 8
# If a process gets this signal it must quit immediately and will not perform any clean-up operations
-protected fun sigkill: Int do return 9
+fun sigkill: Int do return 9
# Sent to a process to indicate user-defined conditions
-protected fun sigusr1: Int do return 10
+fun sigusr1: Int do return 10
# Sent to a process when it makes an invalid virtual memory reference, or segmentation fault
-protected fun sigsegv: Int do return 11
+fun sigsegv: Int do return 11
# Sent to a process to indicate user-defined conditions
-protected fun sigusr2: Int do return 12
+fun sigusr2: Int do return 12
# Sent to a process when it attempts to write to a pipe without a process connected to the other end
-protected fun sigpipe: Int do return 13
+fun sigpipe: Int do return 13
# Alarm Clock signal
-protected fun sigalarm: Int do return 14
+fun sigalarm: Int do return 14
# Software termination signal
-protected fun sigterm: Int do return 15
+fun sigterm: Int do return 15
# Sent to a process when a child process terminates or is interrupted
-protected fun sigchild: Int do return 17
+fun sigchild: Int do return 17
# Tell the operating system to continue (restart) a process previously paused by the SIGSTOP or SIGTSTP signal
-protected fun sigcont: Int do return 18
+fun sigcont: Int do return 18
# Tell the operating system to stop a process
-protected fun sigstop: Int do return 19
+fun sigstop: Int do return 19
# Sent to a process by its terminal to request it to stop temporarily
-protected fun sigtstp: Int do return 20
+fun sigtstp: Int do return 20
# Sent to a process when a socket has urgent or out-of-band data available to read
-protected fun sigurg: Int do return 23
+fun sigurg: Int do return 23
# Sent to a process when it has used the CPU for a duration that exceeds a user-settable value
-protected fun sigxcpu: Int do return 24
+fun sigxcpu: Int do return 24
# Sent to a process when it grows a file larger than the maximum allowed size
-protected fun sigxfsz: Int do return 25
+fun sigxfsz: Int do return 25
# Virtual timer expired
-protected fun sigvtalrm: Int do return 26
+fun sigvtalrm: Int do return 26
# Profiling timer expired
-protected fun sigprof: Int do return 27
+fun sigprof: Int do return 27
# Sent to a process when its controlling terminal changes its window size
-protected fun sigwinch: Int do return 28
+fun sigwinch: Int do return 28
# Sent to a process when the system experiences a power failure
-protected fun sigpwr: Int do return 30
+fun sigpwr: Int do return 30
# Sent to a process when it passes a bad argument to a system call
-protected fun sigsys: Int do return 31
+fun sigsys: Int do return 31
nitlanguage / nit.git / blobdiff