lib/signals/signals.nit.c

   1 /* This file is part of NIT ( http://www.nitlanguage.org ).
   2  *
   3  * Copyright 2011 Alexis Laferrière <alexis.laf@xymus.net>
   4  *
   5  * This file is free software, which comes along with NIT.  This software is
   6  * distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
   7  * without  even  the implied warranty of  MERCHANTABILITY or  FITNESS FOR A
   8  * PARTICULAR PURPOSE.  You can modify it is you want,  provided this header
   9  * is kept unaltered, and a notification of the changes is added.
  10  * You  are  allowed  to  redistribute it and sell it, alone or is a part of
  11  * another product.
  12  */
  13
  14 #undef _POSIX_SOURCE
  15 #define _POSIX_SOURCE 1
  16 #include <signal.h>
  17 #include <stdio.h>
  18
  19 #include "signals.nit.h"
  20
  21 /*
  22         Structure to manage each possible signals
  23         are used in an array of 32 maximum signals.
  24         This array is global to the software.
  25 */
  26 struct nit_signals_ent {
  27         char raised; /* !=0 if has been raised */
  28         SignalHandler handler; /* instance to receive call */
  29         char safely; /* if !=0 then manage signal safely, otherwise react when raised */
  30 } nit_signals_list[32] = {0x0};
  31
  32 /* Receiver to all signals
  33         If unsafe, it calls directly the Nit receiver,
  34         otherwise it marks the signal as raised and returns.
  35 */
  36 void receiver( int sig )
  37 {
  38         if ( sig < 32 && sig >=0 )
  39         {
  40                 if ( nit_signals_list[sig].safely ) {
  41                         nit_signals_list[ sig ].raised += 1;
  42                 } else {
  43                         SignalHandler_receive_signal( nit_signals_list[ sig ].handler, sig );
  44                 }
  45         }
  46 }
  47
  48 /*
  49 C implementation of signals::SignalHandler::handle_signal
  50
  51 Imported methods signatures:
  52         void SignalHandler_receive_signal( SignalHandler recv, bigint signal ) for signals::SignalHandler::receive_signal
  53 */
  54 void SignalHandler_handle_signal___impl( SignalHandler recv, bigint signal, int safely )
  55 {
  56         SignalHandler last_handler;
  57         if ( signal < 32 && signal >=0 ) {
  58                 struct sigaction act;
  59                 sigemptyset(&act.sa_mask);
  60                 act.sa_flags = 0;
  61                 act.sa_handler = receiver;
  62
  63                 sigaction(signal, &act, NULL);
  64
  65                 last_handler = nit_signals_list[signal].handler;
  66                 if ( last_handler != NULL )
  67                         SignalHandler_decr_ref( last_handler );
  68
  69                 nit_signals_list[signal].handler = recv;
  70                 SignalHandler_incr_ref( recv );
  71
  72                 nit_signals_list[signal].safely = safely;
  73         }
  74 }
  75
  76 /*
  77 C implementation of signals::SignalHandler::ignore_signal
  78 */
  79 void SignalHandler_ignore_signal___impl( SignalHandler recv, bigint signal )
  80 {
  81         SignalHandler last_handler;
  82         if ( signal < 32 && signal >=0 ) {
  83                 struct sigaction act;
  84                 sigemptyset(&act.sa_mask);
  85                 act.sa_flags = 0;
  86                 act.sa_handler = SIG_IGN;
  87                 sigaction(signal, &act, NULL);
  88
  89                 last_handler = nit_signals_list[signal].handler;
  90                 if ( last_handler != NULL )
  91                         SignalHandler_decr_ref( last_handler );
  92         }
  93 }
  94
  95 /*
  96 C implementation of signals::SignalHandler::default_signal
  97 */
  98 void SignalHandler_default_signal___impl( SignalHandler recv, bigint signal )
  99 {
 100         SignalHandler last_handler;
 101         if ( signal < 32 && signal >=0 ) {
 102                 struct sigaction act;
 103                 sigemptyset(&act.sa_mask);
 104                 act.sa_flags = 0;
 105                 act.sa_handler = SIG_DFL;
 106                 sigaction(signal, &act, NULL);
 107
 108                 last_handler = nit_signals_list[signal].handler;
 109                 if ( last_handler != NULL )
 110                         SignalHandler_decr_ref( last_handler );
 111         }
 112 }
 113
 114 void Object_set_alarm___impl( Object recv, bigint sec )
 115 {
 116         alarm( sec );
 117 }
 118
 119 /*
 120 C implementation of signals::Object::check_signals
 121
 122 Imported methods signatures:
 123         void SignalHandler_receive_signal( SignalHandler recv, bigint signal ) for signals::SignalHandler::receive_signal
 124 */
 125 int Object_check_signals___impl( Object recv )
 126 {
 127         int sig;
 128         int raised_something = 0;
 129
 130         for ( sig = 0; sig < 32; sig ++ )
 131                 if ( nit_signals_list[sig].raised ) {
 132                         nit_signals_list[sig].raised = 0;
 133                         raised_something = 1;
 134                         SignalHandler_receive_signal( nit_signals_list[sig].handler, sig );
 135                 }
 136
 137         return raised_something;
 138 }