--- gforth/engine/signals.c	2000/07/20 14:07:37	1.7
+++ gforth/engine/signals.c	2003/01/20 17:07:41	1.22
@@ -1,6 +1,6 @@
 /* signal handling
 
-  Copyright (C) 1995,1996,1997,1998 Free Software Foundation, Inc.
+  Copyright (C) 1995,1996,1997,1998,2000 Free Software Foundation, Inc.
 
   This file is part of Gforth.
 
@@ -16,13 +16,13 @@
 
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
-  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
 
 */
 
 
-#define _GNU_SOURCE
-
+#include "config.h"
+#include "forth.h"
 #include <stdio.h>
 #include <setjmp.h>
 #include <string.h>
@@ -31,11 +31,14 @@
 #include <sys/ioctl.h>
 #endif
 /* #include <asm/signal.h> */
+#include <sys/types.h>
 #include <signal.h>
-#include "config.h"
-#include "forth.h"
 #include "io.h"
 
+#ifndef HAVE_STACK_T
+/* Darwin uses "struct sigaltstack" instead of "stack_t" */
+typedef struct sigaltstack stack_t;
+#endif
 
 #define DEFAULTCOLS 80
 #if defined(MSDOS) || defined (_WIN32)
@@ -48,10 +51,14 @@ UCell cols=DEFAULTCOLS;
 UCell rows=DEFAULTROWS;
 
 #ifndef SA_NODEFER
-#define SA_NODEDER 0
+#define SA_NODEFER 0
 /* systems that don't have SA_NODEFER hopefully don't block anyway */
 #endif
 
+#ifndef SA_ONSTACK
+#define SA_ONSTACK 0
+#endif
+
 #ifdef SA_SIGINFO
 void install_signal_handler(int sig, void (*handler)(int, siginfo_t *, void *))
      /* installs three-argument signal handler for sig */
@@ -60,7 +67,7 @@ void install_signal_handler(int sig, voi
 
   action.sa_sigaction=handler;
   sigemptyset(&action.sa_mask);
-  action.sa_flags=SA_RESTART|SA_NODEFER|SA_SIGINFO; /* pass siginfo */
+  action.sa_flags=SA_RESTART|SA_NODEFER|SA_SIGINFO|SA_ONSTACK; /* pass siginfo */
   sigaction(sig, &action, NULL);
 }
 #endif
@@ -73,7 +80,7 @@ Sigfunc *bsd_signal(int signo, Sigfunc *
 
   act.sa_handler=func;
   sigemptyset(&act.sa_mask);
-  act.sa_flags=SA_NODEFER;
+  act.sa_flags=SA_NODEFER; /* SA_ONSTACK does not work for graceful_exit */
   if (sigaction(signo,&act,&oact) < 0)
     return SIG_ERR;
   else
@@ -114,14 +121,20 @@ static void fpe_handler(int sig, siginfo
   int code;
 
   switch(info->si_code) {
+#ifdef FPE_INTDIV
   case FPE_INTDIV: code=-10; break; /* integer divide by zero */
+#endif
+#ifdef FPE_INTOVF
   case FPE_INTOVF: code=-11; break; /* integer overflow */
+#endif
   case FPE_FLTDIV: code=-42; break; /* floating point divide by zero */
   case FPE_FLTOVF: code=-43; break; /* floating point overflow  */
   case FPE_FLTUND: code=-54; break; /* floating point underflow  */
   case FPE_FLTRES: code=-41; break; /* floating point inexact result  */
+#if 0 /* defined by Unix95, but unnecessary */
   case FPE_FLTINV: /* invalid floating point operation  */
   case FPE_FLTSUB: /* subscript out of range  */
+#endif
   default: code=-55; break;
   }
   longjmp(throw_jmp_buf,code);
@@ -163,7 +176,7 @@ static void segv_handler(int sig, siginf
 #endif /* defined(SA_SIGINFO) */
 
 #ifdef SIGCONT
-static void termprep (int sig)
+static void termprep(int sig)
 {
   bsd_signal(sig,termprep);
   terminal_prepped=0;
@@ -174,6 +187,7 @@ void get_winsize()
 {
 #ifdef TIOCGWINSZ
   struct winsize size;
+  size.ws_row = size.ws_col = 0;
   
   if (ioctl (1, TIOCGWINSZ, (char *) &size) >= 0) {
     rows = size.ws_row;
@@ -183,15 +197,15 @@ void get_winsize()
   char *s;
   if ((s=getenv("LINES"))) {
     rows=atoi(s);
-    if (rows==0)
-      rows=DEFAULTROWS;
   }
   if ((s=getenv("COLUMNS"))) {
     rows=atoi(s);
-    if (rows==0)
-      cols=DEFAULTCOLS;
   }
 #endif
+  if (rows==0)
+    rows=DEFAULTROWS;
+  if (rows==0)
+    cols=DEFAULTCOLS;
 }
 
 #ifdef SIGWINCH
@@ -355,6 +369,18 @@ void install_signal_handlers(void)
   };
   int i;
   void (*throw_handler)() = die_on_signal ? graceful_exit : signal_throw;
+#ifdef SIGSTKSZ 
+  stack_t sigstack;
+  int sas_retval=-1;
+
+  sigstack.ss_size=SIGSTKSZ;
+  if ((sigstack.ss_sp = my_alloc(sigstack.ss_size)) != NULL) {
+    sigstack.ss_flags=0;
+    sas_retval=sigaltstack(&sigstack,(stack_t *)0);
+  }
+  if (debug)
+    fprintf(stderr,"sigaltstack: %s\n",strerror(sas_retval));
+#endif
 
 #define DIM(X)		(sizeof (X) / sizeof *(X))
 /*
@@ -366,8 +392,10 @@ void install_signal_handlers(void)
   for (i = 0; i < DIM (sigs_to_quit); i++)
     bsd_signal(sigs_to_quit [i], graceful_exit);
 #ifdef SA_SIGINFO
-  install_signal_handler(SIGFPE, fpe_handler);
-  install_signal_handler(SIGSEGV, segv_handler);
+  if (!die_on_signal) {
+    install_signal_handler(SIGFPE, fpe_handler);
+    install_signal_handler(SIGSEGV, segv_handler);
+  }
 #endif
 #ifdef SIGCONT
     bsd_signal(SIGCONT, termprep);