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/****************************************************************************
* *
* GNAT COMPILER COMPONENTS *
* *
* C T R L _ C *
* *
* C Implementation File *
* *
* Copyright (C) 2002-2022, Free Software Foundation, Inc. *
* *
* GNAT is free software; you can redistribute it and/or modify it under *
* terms of the GNU General Public License as published by the Free Soft- *
* ware Foundation; either version 3, or (at your option) any later ver- *
* sion. GNAT is distributed in the hope that it will be useful, but WITH- *
* OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY *
* or FITNESS FOR A PARTICULAR PURPOSE. *
* *
* As a special exception under Section 7 of GPL version 3, you are granted *
* additional permissions described in the GCC Runtime Library Exception, *
* version 3.1, as published by the Free Software Foundation. *
* *
* You should have received a copy of the GNU General Public License and *
* a copy of the GCC Runtime Library Exception along with this program; *
* see the files COPYING3 and COPYING.RUNTIME respectively. If not, see *
* <http://www.gnu.org/licenses/>. *
* *
* GNAT was originally developed by the GNAT team at New York University. *
* Extensive contributions were provided by Ada Core Technologies Inc. *
* *
****************************************************************************/
#ifndef IN_RTS
#include "config.h"
#include "system.h"
#endif
/* Services to intercept Ctrl-C */
/* __gnat_install_int_handler will install the specified handler.
If called for the first time, it will also save the original handler */
void __gnat_install_int_handler (void (*) (void));
/* __gnat_uninstall_int_handler will reinstall the original handler */
void __gnat_uninstall_int_handler (void);
/* POSIX implementation */
#if (defined (__unix__) || defined (_AIX) || defined (__APPLE__)) \
|| defined (VMS) && !defined (__vxworks)
#ifdef VMS
/* On VMS _gnat_handle_vms_condition gets control first, and it has to
resignal the Ctrl/C in order for sigaction to gain control and execute
the user handler routine, but in doing so propagates the condition
causing the program to terminate. So instead we install a dummy handler
routine and put the real user handler in a special global variable so
that __gnat_handle_vms_condition can declare an AST to asynchronously
execute the Ctrl/C user handler at some future time and allow
__gnat_handle_vms_condition to return and not be held up waiting for
the potentially unbounded time required to execute the Crtl/C handler. */
void
dummy_handler () {}
/* Lives in init.c. */
extern void (*__gnat_ctrl_c_handler) (void);
#endif
#include <signal.h>
void (*sigint_intercepted) (void) = 0;
struct sigaction original_act;
static void
__gnat_int_handler (int sig __attribute__ ((unused)))
{
if (sigint_intercepted != 0)
sigint_intercepted ();
}
/* Install handler and save original handler. */
void
__gnat_install_int_handler (void (*proc) (void))
{
struct sigaction act;
if (sigint_intercepted == 0)
{
act.sa_handler = __gnat_int_handler;
#if defined (__Lynx__) || defined (VMS) || defined(__DJGPP__)
/* LynxOS, VMS and DJGPP do not support SA_RESTART. */
act.sa_flags = 0;
#else
act.sa_flags = SA_RESTART;
#endif
sigemptyset (&act.sa_mask);
sigaction (SIGINT, &act, &original_act);
}
#ifdef VMS
sigint_intercepted = &dummy_handler;
__gnat_ctrl_c_handler = proc;
#else
sigint_intercepted = proc;
#endif
}
/* Restore original handler */
void
__gnat_uninstall_int_handler (void)
{
if (sigint_intercepted != 0)
{
sigaction (SIGINT, &original_act, 0);
sigint_intercepted = 0;
}
#ifdef VMS
if (__gnat_ctrl_c_handler)
__gnat_ctrl_c_handler = 0;
#endif
}
/* Windows implementation */
#elif defined (__MINGW32__)
#include "mingw32.h"
#include <windows.h>
void (*sigint_intercepted) (void) = NULL;
static BOOL WINAPI
__gnat_int_handler (DWORD dwCtrlType)
{
switch (dwCtrlType)
{
case CTRL_C_EVENT:
case CTRL_BREAK_EVENT:
if (sigint_intercepted != 0)
{
sigint_intercepted ();
return TRUE;
}
break;
case CTRL_CLOSE_EVENT:
case CTRL_LOGOFF_EVENT:
case CTRL_SHUTDOWN_EVENT:
break;
}
return FALSE;
}
void
__gnat_install_int_handler (void (*proc) (void))
{
if (sigint_intercepted == NULL)
SetConsoleCtrlHandler (__gnat_int_handler, TRUE);
sigint_intercepted = proc;
}
void
__gnat_uninstall_int_handler (void)
{
if (sigint_intercepted != NULL)
SetConsoleCtrlHandler (__gnat_int_handler, FALSE);
sigint_intercepted = NULL;
}
/* Default implementation: do nothing */
#else
void
__gnat_install_int_handler (void (*proc) (void) __attribute__ ((unused)))
{
}
void
__gnat_uninstall_int_handler (void)
{
}
#endif
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