Add a helper process to Chrome Frame to allow for non-administrative installs...

chrome_frame/bho_loader.h

+// Copyright (c) 2010 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.
+
+#ifndef CHROME_FRAME_BHO_LOADER_H_
+#define CHROME_FRAME_BHO_LOADER_H_
+
+#include <windows.h>
+
+// Forward.
+class EventHooker;
+
+// This class simulates BHO loading in an IE process. It watches for the
+// creation of a specific window and then retrieves the web browser object
+// for that window and simulates loading of the BHO.
+class BHOLoader {
+ public:
+  BHOLoader();
+  ~BHOLoader();
+
+  // Callback invoked on receipt of an accessibility event.
+  void OnHookEvent(DWORD event, HWND window);
+
+  // Call this to install event hooks that will trigger on window creation
+  // and reparenting. Returns true if the hooks are successfully installed,
+  // false otherwise.
+  bool StartHook();
+
+  // Call this to remove the event hooks that are installed by StartHook().
+  void StopHook();
+
+  // Retrieve the BHOLoader instance. Note that this is NOT thread-safe.
+  static BHOLoader* GetInstance();
+
+ private:
+  EventHooker* hooker_;
+};
+
+#endif  // CHROME_FRAME_BHO_LOADER_H_