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         if ( signal < 32 && signal >=0 ) {
  57                 struct sigaction act;
  58                 sigemptyset(&act.sa_mask);
  59                 act.sa_flags = 0;
  60                 act.sa_handler = receiver;
  61
  62                 sigaction(signal, &act, NULL);
  63
  64                 SignalHandler last_handler = nit_signals_list[signal].handler;
  65                 if ( last_handler != NULL )
  66                         SignalHandler_decr_ref( last_handler );
  67
  68                 nit_signals_list[signal].handler = recv;
  69                 SignalHandler_incr_ref( recv );
  70
  71                 nit_signals_list[signal].safely = safely;
  72         }
  73 }
  74
  75 /*
  76 C implementation of signals::SignalHandler::ignore_signal
  77 */
  78 void SignalHandler_ignore_signal___impl( SignalHandler recv, bigint signal )
  79 {
  80         if ( signal < 32 && signal >=0 ) {
  81                 struct sigaction act;
  82                 sigemptyset(&act.sa_mask);
  83                 act.sa_flags = 0;
  84                 act.sa_handler = SIG_IGN;
  85                 sigaction(signal, &act, NULL);
  86
  87                 SignalHandler last_handler = nit_signals_list[signal].handler;
  88                 if ( last_handler != NULL )
  89                         SignalHandler_decr_ref( last_handler );
  90         }
  91 }
  92
  93 /*
  94 C implementation of signals::SignalHandler::default_signal
  95 */
  96 void SignalHandler_default_signal___impl( SignalHandler recv, bigint signal )
  97 {
  98         if ( signal < 32 && signal >=0 ) {
  99                 struct sigaction act;
 100                 sigemptyset(&act.sa_mask);
 101                 act.sa_flags = 0;
 102                 act.sa_handler = SIG_DFL;
 103                 sigaction(signal, &act, NULL);
 104
 105                 SignalHandler last_handler = nit_signals_list[signal].handler;
 106                 if ( last_handler != NULL )
 107                         SignalHandler_decr_ref( last_handler );
 108         }
 109 }
 110
 111 void Object_set_alarm___impl( Object recv, bigint sec )
 112 {
 113         alarm( sec );
 114 }
 115
 116 /*
 117 C implementation of signals::Object::check_signals
 118
 119 Imported methods signatures:
 120         void SignalHandler_receive_signal( SignalHandler recv, bigint signal ) for signals::SignalHandler::receive_signal
 121 */
 122 int Object_check_signals___impl( Object recv )
 123 {
 124         int sig;
 125         int raised_something = 0;
 126
 127         for ( sig = 0; sig < 32; sig ++ )
 128                 if ( nit_signals_list[sig].raised ) {
 129                         nit_signals_list[sig].raised = 0;
 130                         raised_something = 1;
 131                         SignalHandler_receive_signal( nit_signals_list[sig].handler, sig );
 132                 }
 133
 134         return raised_something;
 135 }