--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/vm-limit.c	Mon Aug 13 08:45:50 2007 +0200
@@ -0,0 +1,135 @@
+/* Functions for memory limit warnings.
+   Copyright (C) 1990, 1992 Free Software Foundation, Inc.
+
+This file is part of XEmacs.
+
+XEmacs 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 2, or (at your option) any
+later version.
+
+XEmacs 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.
+
+You should have received a copy of the GNU General Public License
+along with XEmacs; see the file COPYING.  If not, write to
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+/* Synched up with: FSF 19.30. */
+
+#ifdef emacs
+#include <config.h>
+#include "lisp.h"
+#endif
+
+#ifndef emacs
+#include <stddef.h>
+typedef size_t SIZE;
+typedef void *POINTER;
+#define EXCEEDS_LISP_PTR(x) 0
+#endif
+
+#include "mem-limits.h"
+
+/*
+  Level number of warnings already issued.
+  0 -- no warnings issued.
+  1 -- 75% warning already issued.
+  2 -- 85% warning already issued.
+  3 -- 95% warning issued; keep warning frequently.
+*/
+static int warnlevel;
+
+/* Function to call to issue a warning;
+   0 means don't issue them.  */
+static void (*warn_function) (CONST char *);
+
+/* Get more memory space, complaining if we're near the end. */
+
+static void
+check_memory_limits ()
+{
+  extern POINTER (*__morecore) ();
+
+  POINTER cp;
+  unsigned long five_percent;
+  unsigned long data_size;
+
+  if (lim_data == 0)
+    get_lim_data ();
+  five_percent = lim_data / 20;
+
+  /* Find current end of memory and issue warning if getting near max */
+  cp = (char *) (*__morecore) (0);
+  data_size = (char *) cp - (char *) data_space_start;
+
+  if (warn_function)
+    switch (warnlevel)
+      {
+      case 0: 
+	if (data_size > five_percent * 15)
+	  {
+	    warnlevel++;
+	    (*warn_function) ("Warning: past 75% of memory limit");
+	  }
+	break;
+
+      case 1: 
+	if (data_size > five_percent * 17)
+	  {
+	    warnlevel++;
+	    (*warn_function) ("Warning: past 85% of memory limit");
+	  }
+	break;
+
+      case 2: 
+	if (data_size > five_percent * 19)
+	  {
+	    warnlevel++;
+	    (*warn_function) ("Warning: past 95% of memory limit");
+	  }
+	break;
+
+      default:
+	(*warn_function) ("Warning: past acceptable memory limits");
+	break;
+      }
+
+  /* If we go down below 70% full, issue another 75% warning
+     when we go up again.  */
+  if (data_size < five_percent * 14)
+    warnlevel = 0;
+  /* If we go down below 80% full, issue another 85% warning
+     when we go up again.  */
+  else if (warnlevel > 1 && data_size < five_percent * 16)
+    warnlevel = 1;
+  /* If we go down below 90% full, issue another 95% warning
+     when we go up again.  */
+  else if (warnlevel > 2 && data_size < five_percent * 18)
+    warnlevel = 2;
+
+  if (EXCEEDS_LISP_PTR (cp))
+    (*warn_function) ("Warning: memory in use exceeds lisp pointer size");
+}
+
+/* Cause reinitialization based on job parameters;
+   also declare where the end of pure storage is. */
+
+void
+memory_warnings (void *start, void (*warnfun) (CONST char *))
+{
+  extern void (* __after_morecore_hook) ();     /* From gmalloc.c */
+
+  if (start)
+    data_space_start = start;
+  else
+    data_space_start = start_of_data ();
+
+#ifndef _NO_MALLOC_WARNING_
+  warn_function = warnfun;
+  __after_morecore_hook = check_memory_limits;
+#endif
+}