linux: add flash workarounds

webkit/glue/plugins/flash_workarounds_linux.cc

+// Copyright (c) 2006-2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "webkit/glue/plugins/flash_workarounds_linux.h"
+
+#include <dlfcn.h>
+#include <gtk/gtk.h>
+#include <gdk/gdkx.h>
+
+#include "base/logging.h"
+#include "base/native_library.h"
+
+namespace {
+
+typedef void (*Type_gtk_widget_modify_bg)(
+    GtkWidget* widget, GtkStateType state, const GdkColor* color);
+Type_gtk_widget_modify_bg g_real_gtk_widget_modify_bg = NULL;
+bool g_enable_gtk_widget_modify_bg_workaround = false;
+
+typedef Status (* Type_XGetWindowAttributes)(
+    Display *display, Window w, XWindowAttributes *window_attributes_return);
+Type_XGetWindowAttributes g_real_XGetWindowAttributes = NULL;
+
+}  // anonymous namespace
+
+extern "C" {
+
+// Flash calls gtk_widget_modify_bg from an expose handler, but that function
+// can generate more expose events, leading to an infinite loop.
+// So we intercept that function and disable it in the flash plugin process.
+void gtk_widget_modify_bg(GtkWidget* widget, GtkStateType state,
+                          const GdkColor* color) {
+  if (!g_real_gtk_widget_modify_bg) {
+    g_real_gtk_widget_modify_bg = (Type_gtk_widget_modify_bg)(
+        dlsym(RTLD_NEXT, "gtk_widget_modify_bg"));
+    DCHECK(g_real_gtk_widget_modify_bg);
+  }
+  if (g_enable_gtk_widget_modify_bg_workaround)
+    return;
+  g_real_gtk_widget_modify_bg(widget, state, color);
+}
+
+// Flash calls XGetWindowAttributes with a NULL display, which crashes.
+// So we intercept that function and make sure the display is set.
+Status XGetWindowAttributes(Display *display, Window w,
+                            XWindowAttributes *window_attributes_return) {
+  if (!g_real_XGetWindowAttributes) {
+    g_real_XGetWindowAttributes = (Type_XGetWindowAttributes)(
+        dlsym(RTLD_NEXT, "XGetWindowAttributes"));
+    DCHECK(g_real_XGetWindowAttributes);
+  }
+  if (!display)
+    display = GDK_DISPLAY();
+  DCHECK(display);
+  return g_real_XGetWindowAttributes(display, w, window_attributes_return);
+}
+
+}  // extern "C"
+
+void EnableFlashWorkarounds(const FilePath &library_path) {
+  base::AddShallowBindPath(library_path);
+  g_enable_gtk_widget_modify_bg_workaround = true;
+}