lib/signals/signals.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org ).
   2 #
   3 # Copyright 2011 Alexis Laferrière <alexis.laf@xymus.net>
   4 #
   5 # Licensed under the Apache License, Version 2.0 (the "License");
   6 # you may not use this file except in compliance with the License.
   7 # You may obtain a copy of the License at
   8 #
   9 #     http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16
  17 # Module to manage standard C signals
  18 module signals
  19
  20 # Receives the callback from system when a given signal arise
  21 interface SignalHandler
  22         # Called on any signal received
  23         fun receive_signal( signal : Int ) is abstract
  24
  25         # Called on any unsafe signal received
  26         fun receive_signal_unsafe( signal : Int ) is abstract
  27
  28         # Set the receiver as the handler of the signal
  29         # If safely, receiver will be called when check_signals in invoked
  30         #    otherwise the receiver is invoked when the signal is raised, it may
  31         #    crash the Nit system but is unavoidable for unstoppable signals
  32         fun handle_signal( signal : Int, safely : Bool ) is extern import
  33                 receive_signal
  34
  35         # Set to ignore the signal
  36         fun ignore_signal( signal : Int ) is extern
  37
  38         # Set default action for the signal
  39         fun default_signal( signal : Int ) is extern
  40
  41         fun sigalarm : Int do return 14
  42         fun sighup : Int do return 1
  43         fun sigint : Int do return 2
  44         fun sigkill : Int do return 9
  45         fun sigpipe : Int do return 13
  46         fun sigterm : Int do return 15
  47         fun sigabrt : Int do return 6
  48         fun sigfpe : Int do return 8
  49         fun sigquit : Int do return 3
  50         fun sigsegv : Int do return 11
  51 end
  52
  53 redef interface Object
  54
  55         # Check signals for safe operation
  56         # will callback receiver of raised signals
  57         # can callback any instance of SignalHandler, not just this one
  58         protected fun check_signals : Bool is extern import SignalHandler::receive_signal
  59
  60         # Set alarm signal
  61         # can callback any instance of SignalHandler, not just this one
  62         protected fun set_alarm( sec : Int ) is extern
  63 end