--- gforth/engine/signals.c	2000/07/20 13:29:43	1.5
+++ gforth/engine/signals.c	2002/10/25 15:57:03	1.15
@@ -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.
 
@@ -16,7 +16,7 @@
 
   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.
 
 */
 
@@ -47,6 +47,11 @@
 UCell cols=DEFAULTCOLS;
 UCell rows=DEFAULTROWS;
 
+#ifndef SA_NODEFER
+#define SA_NODEFER 0
+/* systems that don't have SA_NODEFER hopefully don't block anyway */
+#endif
+
 #ifdef SA_SIGINFO
 void install_signal_handler(int sig, void (*handler)(int, siginfo_t *, void *))
      /* installs three-argument signal handler for sig */
@@ -55,7 +60,7 @@ void install_signal_handler(int sig, voi
 
   action.sa_sigaction=handler;
   sigemptyset(&action.sa_mask);
-  action.sa_flags=SA_RESTART|SA_SIGINFO; /* pass siginfo */
+  action.sa_flags=SA_RESTART|SA_NODEFER|SA_SIGINFO|SA_ONSTACK; /* pass siginfo */
   sigaction(sig, &action, NULL);
 }
 #endif
@@ -68,7 +73,7 @@ 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;
   if (sigaction(signo,&act,&oact) < 0)
     return SIG_ERR;
   else
@@ -158,7 +163,7 @@ 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;
@@ -169,6 +174,7 @@ 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;
@@ -178,15 +184,15 @@ 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
@@ -350,6 +356,16 @@ void install_signal_handlers(void)
   };
   int i;
   void (*throw_handler)() = die_on_signal ? graceful_exit : signal_throw;
+  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));
 
 #define DIM(X)		(sizeof (X) / sizeof *(X))
 /*
@@ -361,8 +377,10 @@ 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);