--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/vdb-win32.c	Fri Nov 25 01:42:08 2005 +0000
@@ -0,0 +1,100 @@
+/* Virtual diry bit implementation for XEmacs.
+   Copyright (C) 2005 Marcus Crestani.
+
+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: Not in FSF. */
+
+#include <config.h>
+#include "lisp.h"
+#include "gc.h"
+#include "mc-alloc.h"
+#include "vdb.h"
+
+#include "syswindows.h"
+
+
+DWORD WINAPI 
+win32_fault_handler (LPEXCEPTION_POINTERS e)
+{
+#define GET_FAULT_ADDRESS (void *) e->ExceptionRecord->ExceptionInformation[1]
+  if ((e->ExceptionRecord->ExceptionCode == EXCEPTION_ACCESS_VIOLATION)
+      && (e->ExceptionRecord->ExceptionInformation[0] == 1)
+      && write_barrier_enabled
+      && (fault_on_protected_page (GET_FAULT_ADDRESS)))
+    {
+      vdb_designate_modified (GET_FAULT_ADDRESS);
+      unprotect_page_and_mark_dirty (GET_FAULT_ADDRESS);
+      return EXCEPTION_CONTINUE_EXECUTION;
+    } 
+  else
+    return EXCEPTION_CONTINUE_SEARCH;
+}
+
+typedef DWORD (WINAPI *gcPVECTORED_EXCEPTION_HANDLER) (LPEXCEPTION_POINTERS e);
+
+
+void
+vdb_install_signal_handler (void)
+{
+  HMODULE hm;
+  PVOID (WINAPI *aveh) (ULONG, gcPVECTORED_EXCEPTION_HANDLER);
+  
+  /* See init_signals_very_early () in signal.c. */
+  if (noninteractive && !initialized)
+    {
+      allow_incremental_gc = 0;
+      return;
+    }
+
+  hm = qxeGetModuleHandle (XETEXT ("kernel32"));
+  if (hm)
+    aveh = (PVOID (WINAPI *) (ULONG, gcPVECTORED_EXCEPTION_HANDLER))
+      GetProcAddress (hm, "AddVectoredExceptionHandler");
+  else
+    {
+      fprintf (stderr, "\nFAILED TO LOAD LIBRARY\n");
+      aveh = NULL;
+    }
+  if (aveh)
+    {
+      allow_incremental_gc = 1;
+      aveh (TRUE, win32_fault_handler);
+    }
+  else
+    {
+      fprintf (stderr, "\nFAILED TO INSTALL SIGNAL HANDLER\n");
+      ABORT ();
+    }
+}
+
+
+void
+vdb_protect (void *ptr, EMACS_INT len)
+{
+  DWORD old;
+  VirtualProtect (ptr, len, PAGE_READONLY, &old);
+}
+
+
+void
+vdb_unprotect (void *ptr, EMACS_INT len)
+{
+  DWORD old;
+  VirtualProtect (ptr, len, PAGE_READWRITE, &old);
+}