widget/gtk/mozgtk/mozgtk.c

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "mozilla/Types.h"
   8
   9 #include <gdk/gdk.h>
  10
  11 // Dummy call to gtk3 library to prevent the linker from removing
  12 // the gtk3 dependency with --as-needed.
  13 // see toolkit/library/moz.build for details.
  14 MOZ_EXPORT void mozgtk_linker_holder() { gdk_display_get_default(); }
  15
  16 #ifdef MOZ_X11
  17 #  include <X11/Xlib.h>
  18 // Bug 1271100
  19 // We need to trick system Cairo into not using the XShm extension due to
  20 // a race condition in it that results in frequent BadAccess errors. Cairo
  21 // relies upon XShmQueryExtension to initially detect if XShm is available.
  22 // So we define our own stub that always indicates XShm not being present.
  23 // mozgtk loads before libXext/libcairo and so this stub will take priority.
  24 // Our tree usage goes through xcb and remains unaffected by this.
  25 //
  26 // This is also used to force libxul to depend on the mozgtk library. If we
  27 // ever can remove this workaround for system Cairo, we'll need something
  28 // to replace it for that purpose.
  29 MOZ_EXPORT Bool XShmQueryExtension(Display* aDisplay) { return False; }
  30 #endif