base/win/iunknown_impl.cc

   1 // Copyright (c) 2011 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 #include "base/win/iunknown_impl.h"
   6
   7 namespace base {
   8 namespace win {
   9
  10 IUnknownImpl::IUnknownImpl()
  11     : ref_count_(0) {
  12 }
  13
  14 IUnknownImpl::~IUnknownImpl() {
  15 }
  16
  17 ULONG STDMETHODCALLTYPE IUnknownImpl::AddRef() {
  18   base::AtomicRefCountInc(&ref_count_);
  19   return 1;
  20 }
  21
  22 ULONG STDMETHODCALLTYPE IUnknownImpl::Release() {
  23   if (!base::AtomicRefCountDec(&ref_count_)) {
  24     delete this;
  25     return 0;
  26   }
  27   return 1;
  28 }
  29
  30 STDMETHODIMP IUnknownImpl::QueryInterface(REFIID riid, void** ppv) {
  31   if (riid == IID_IUnknown) {
  32     *ppv = static_cast<IUnknown*>(this);
  33     AddRef();
  34     return S_OK;
  35   }
  36
  37   *ppv = NULL;
  38   return E_NOINTERFACE;
  39 }
  40
  41 }  // namespace win
  42 }  // namespace base