3092
+ − 1 /* Virtual diry bit implementation for XEmacs.
+ − 2 Copyright (C) 2005 Marcus Crestani.
+ − 3
+ − 4 This file is part of XEmacs.
+ − 5
+ − 6 XEmacs is free software; you can redistribute it and/or modify it
+ − 7 under the terms of the GNU General Public License as published by the
+ − 8 Free Software Foundation; either version 2, or (at your option) any
+ − 9 later version.
+ − 10
+ − 11 XEmacs is distributed in the hope that it will be useful, but WITHOUT
+ − 12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ − 13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ − 14 for more details.
+ − 15
+ − 16 You should have received a copy of the GNU General Public License
+ − 17 along with XEmacs; see the file COPYING. If not, write to
+ − 18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ − 19 Boston, MA 02111-1307, USA. */
+ − 20
+ − 21 /* Synched up with: Not in FSF. */
+ − 22
+ − 23 #include <config.h>
+ − 24 #include "lisp.h"
+ − 25 #include "gc.h"
+ − 26 #include "mc-alloc.h"
+ − 27 #include "vdb.h"
+ − 28
+ − 29 #include "syswindows.h"
+ − 30
+ − 31
+ − 32 DWORD WINAPI
+ − 33 win32_fault_handler (LPEXCEPTION_POINTERS e)
+ − 34 {
+ − 35 #define GET_FAULT_ADDRESS (void *) e->ExceptionRecord->ExceptionInformation[1]
+ − 36 if ((e->ExceptionRecord->ExceptionCode == EXCEPTION_ACCESS_VIOLATION)
+ − 37 && (e->ExceptionRecord->ExceptionInformation[0] == 1)
+ − 38 && write_barrier_enabled
+ − 39 && (fault_on_protected_page (GET_FAULT_ADDRESS)))
+ − 40 {
+ − 41 vdb_designate_modified (GET_FAULT_ADDRESS);
+ − 42 unprotect_page_and_mark_dirty (GET_FAULT_ADDRESS);
+ − 43 return EXCEPTION_CONTINUE_EXECUTION;
+ − 44 }
+ − 45 else
+ − 46 return EXCEPTION_CONTINUE_SEARCH;
+ − 47 }
+ − 48
+ − 49 typedef DWORD (WINAPI *gcPVECTORED_EXCEPTION_HANDLER) (LPEXCEPTION_POINTERS e);
+ − 50
+ − 51
+ − 52 void
+ − 53 vdb_install_signal_handler (void)
+ − 54 {
+ − 55 HMODULE hm;
+ − 56 PVOID (WINAPI *aveh) (ULONG, gcPVECTORED_EXCEPTION_HANDLER);
+ − 57
+ − 58 /* See init_signals_very_early () in signal.c. */
+ − 59 if (noninteractive && !initialized)
+ − 60 {
+ − 61 allow_incremental_gc = 0;
+ − 62 return;
+ − 63 }
+ − 64
+ − 65 hm = qxeGetModuleHandle (XETEXT ("kernel32"));
+ − 66 if (hm)
+ − 67 aveh = (PVOID (WINAPI *) (ULONG, gcPVECTORED_EXCEPTION_HANDLER))
+ − 68 GetProcAddress (hm, "AddVectoredExceptionHandler");
+ − 69 else
+ − 70 {
+ − 71 fprintf (stderr, "\nFAILED TO LOAD LIBRARY\n");
+ − 72 aveh = NULL;
+ − 73 }
+ − 74 if (aveh)
+ − 75 {
+ − 76 allow_incremental_gc = 1;
+ − 77 aveh (TRUE, win32_fault_handler);
+ − 78 }
+ − 79 else
+ − 80 {
+ − 81 fprintf (stderr, "\nFAILED TO INSTALL SIGNAL HANDLER\n");
+ − 82 ABORT ();
+ − 83 }
+ − 84 }
+ − 85
+ − 86
+ − 87 void
+ − 88 vdb_protect (void *ptr, EMACS_INT len)
+ − 89 {
+ − 90 DWORD old;
+ − 91 VirtualProtect (ptr, len, PAGE_READONLY, &old);
+ − 92 }
+ − 93
+ − 94
+ − 95 void
+ − 96 vdb_unprotect (void *ptr, EMACS_INT len)
+ − 97 {
+ − 98 DWORD old;
+ − 99 VirtualProtect (ptr, len, PAGE_READWRITE, &old);
+ − 100 }