gcc/ada/ctrl_c.c

   1 /****************************************************************************
   2  *                                                                          *
   3  *                         GNAT COMPILER COMPONENTS                         *
   4  *                                                                          *
   5  *                               C T R L _ C                                *
   6  *                                                                          *
   7  *                          C Implementation File                           *
   8  *                                                                          *
   9  *        Copyright (C) 2002-2003, Free Software Foundation, Inc.           *
  10  *                                                                          *
  11  * GNAT is free software;  you can  redistribute it  and/or modify it under *
  12  * terms of the  GNU General Public License as published  by the Free Soft- *
  13  * ware  Foundation;  either version 2,  or (at your option) any later ver- *
  14  * sion.  GNAT is distributed in the hope that it will be useful, but WITH- *
  15  * OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY *
  16  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License *
  17  * for  more details.  You should have  received  a copy of the GNU General *
  18  * Public License  distributed with GNAT;  see file COPYING.  If not, write *
  19  * to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, *
  20  * Boston, MA 02110-1301, USA.                                              *
  21  *                                                                          *
  22  * As a  special  exception,  if you  link  this file  with other  files to *
  23  * produce an executable,  this file does not by itself cause the resulting *
  24  * executable to be covered by the GNU General Public License. This except- *
  25  * ion does not  however invalidate  any other reasons  why the  executable *
  26  * file might be covered by the  GNU Public License.                        *
  27  *                                                                          *
  28  * GNAT was originally developed  by the GNAT team at  New York University. *
  29  * Extensive contributions were provided by Ada Core Technologies Inc.      *
  30  *                                                                          *
  31  ****************************************************************************/
  32
  33 #ifdef IN_RTS
  34 #include "tconfig.h"
  35 #include "tsystem.h"
  36 #include <sys/stat.h>
  37 #else
  38 #include "config.h"
  39 #include "system.h"
  40 #endif
  41
  42 /* Services to intercept Ctrl-C */
  43
  44 /* __gnat_install_int_handler will install the specified handler.
  45    If called for the first time, it will also save the original handler */
  46 void __gnat_install_int_handler (void (*) (void));
  47
  48 /* __gnat_uninstall_int_handler will reinstall the original handler */
  49 void __gnat_uninstall_int_handler (void);
  50
  51 /* POSIX implementation */
  52
  53 #if (defined (_AIX) || defined (unix)) && !defined (__vxworks)
  54
  55 #include <signal.h>
  56
  57 void (*sigint_intercepted) (void) = 0;
  58
  59 struct sigaction original_act;
  60
  61 static void
  62 __gnat_int_handler (int sig __attribute__ ((unused)))
  63 {
  64   if (sigint_intercepted != 0)
  65     sigint_intercepted ();
  66 }
  67
  68 /* Install handler and save original handler. */
  69
  70 void
  71 __gnat_install_int_handler (void (*proc) (void))
  72 {
  73   struct sigaction act;
  74
  75   if (sigint_intercepted == 0)
  76     {
  77       act.sa_handler = __gnat_int_handler;
  78       act.sa_flags = SA_RESTART;
  79       sigemptyset (&act.sa_mask);
  80       sigaction (SIGINT, &act, &original_act);
  81     }
  82
  83   sigint_intercepted = proc;
  84 }
  85
  86 /* Restore original handler */
  87
  88 void
  89 __gnat_uninstall_int_handler (void)
  90 {
  91  if (sigint_intercepted != 0)
  92    {
  93      sigaction (SIGINT, &original_act, 0);
  94      sigint_intercepted = 0;
  95    }
  96 }
  97
  98 /* Windows implementation */
  99
 100 #elif defined (__MINGW32__)
 101
 102 #include "mingw32.h"
 103 #include <windows.h>
 104
 105 void (*sigint_intercepted) (void) = NULL;
 106
 107 static BOOL WINAPI
 108 __gnat_int_handler  (DWORD dwCtrlType)
 109 {
 110   switch (dwCtrlType)
 111     {
 112     case CTRL_C_EVENT:
 113     case CTRL_BREAK_EVENT:
 114       if (sigint_intercepted != 0)
 115         sigint_intercepted ();
 116       break;
 117
 118     case CTRL_CLOSE_EVENT:
 119     case CTRL_LOGOFF_EVENT:
 120     case CTRL_SHUTDOWN_EVENT:
 121       break;
 122     }
 123 }
 124
 125 void
 126 __gnat_install_int_handler (void (*proc) (void))
 127 {
 128   if (sigint_intercepted == NULL)
 129     SetConsoleCtrlHandler (__gnat_int_handler, TRUE);
 130
 131   sigint_intercepted = proc;
 132 }
 133
 134 void
 135 __gnat_uninstall_int_handler (void)
 136 {
 137   if (sigint_intercepted != NULL)
 138     SetConsoleCtrlHandler (__gnat_int_handler, FALSE);
 139
 140   sigint_intercepted = NULL;
 141 }
 142
 143 /* Default implementation: do nothing */
 144
 145 #else
 146
 147 void
 148 __gnat_install_int_handler (void (*proc) (void) __attribute__ ((unused)))
 149 {
 150 }
 151
 152 void
 153 __gnat_uninstall_int_handler (void)
 154 {
 155 }
 156 #endif