base/win/iunknown_impl.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef BASE_WIN_IUNKNOWN_IMPL_H_
   6 #define BASE_WIN_IUNKNOWN_IMPL_H_
   7
   8 #include <unknwn.h>
   9
  10 #include "base/atomic_ref_count.h"
  11 #include "base/base_export.h"
  12 #include "base/compiler_specific.h"
  13
  14 namespace base {
  15 namespace win {
  16
  17 // IUnknown implementation for other classes to derive from.
  18 class BASE_EXPORT IUnknownImpl : public IUnknown {
  19  public:
  20   IUnknownImpl();
  21
  22   virtual ULONG STDMETHODCALLTYPE AddRef() OVERRIDE;
  23   virtual ULONG STDMETHODCALLTYPE Release() OVERRIDE;
  24
  25   // Subclasses should extend this to return any interfaces they provide.
  26   virtual STDMETHODIMP QueryInterface(REFIID riid, void** ppv) OVERRIDE;
  27
  28  protected:
  29   virtual ~IUnknownImpl();
  30
  31  private:
  32   AtomicRefCount ref_count_;
  33 };
  34
  35 }  // namespace win
  36 }  // namespace base
  37
  38 #endif  // BASE_WIN_IUNKNOWN_IMPL_H_