| /* Break.c - access to the signal handler for catching control C. |
| |
| Copyright (C) 2004-2023 Free Software Foundation, Inc. |
| Contributed by Gaius Mulley <gaius@glam.ac.uk>. |
| |
| This file is part of GNU Modula-2. |
| |
| GNU Modula-2 is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3, or (at your option) |
| any later version. |
| |
| GNU Modula-2 is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| 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/>. */ |
| |
| #include <stdio.h> |
| #include <stdarg.h> |
| #include "gm2-libs-host.h" |
| |
| #if defined(HAVE_STDLIB_H) |
| #include <stdlib.h> |
| #endif |
| |
| #if defined(HAVE_MALLOC_H) |
| #include <malloc.h> |
| #endif |
| |
| typedef void (*PROC) (void); |
| |
| #if defined(HAVE_SIGNAL_H) |
| #include <signal.h> |
| |
| struct plist |
| { |
| PROC proc; |
| struct plist *next; |
| }; |
| |
| static struct plist *head = NULL; |
| |
| /* localHandler - dismisses the parameter, p, and invokes the GNU |
| Modula-2 handler. */ |
| |
| static void |
| localHandler (int p) |
| { |
| if (head != NULL) |
| head->proc (); |
| } |
| |
| /* EnableBreak - enable the current break handler. */ |
| |
| void |
| Break_EnableBreak (void) |
| { |
| signal (SIGINT, localHandler); |
| } |
| |
| /* DisableBreak - disable the current break handler (and all |
| installed handlers). */ |
| |
| void |
| Break_DisableBreak (void) |
| { |
| signal (SIGINT, SIG_IGN); |
| } |
| |
| /* InstallBreak - installs a procedure, p, to be invoked when a |
| ctrl-c is caught. Any number of these procedures may be stacked. |
| Only the top procedure is run when ctrl-c is caught. */ |
| |
| void |
| Break_InstallBreak (PROC p) |
| { |
| struct plist *q = (struct plist *)malloc (sizeof (struct plist)); |
| |
| if (q == NULL) |
| { |
| perror ("out of memory error in module Break"); |
| exit (1); |
| } |
| q->next = head; |
| head = q; |
| head->proc = p; |
| } |
| |
| /* UnInstallBreak - pops the break handler stack. */ |
| |
| void |
| Break_UnInstallBreak (void) |
| { |
| struct plist *q = head; |
| |
| if (head != NULL) |
| { |
| head = head->next; |
| free (q); |
| } |
| } |
| #else |
| void |
| Break_EnableBreak (void) |
| { |
| } |
| void |
| Break_DisableBreak (void) |
| { |
| } |
| void |
| Break_InstallBreak (PROC *p) |
| { |
| } |
| void |
| Break_UnInstallBreak (void) |
| { |
| } |
| #endif |