1/* 2 * Copyright (c) 2013 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11#ifndef WEBRTC_MODULES_DESKTOP_CAPTURE_WIN_SCOPED_GDI_HANDLE_H_ 12#define WEBRTC_MODULES_DESKTOP_CAPTURE_WIN_SCOPED_GDI_HANDLE_H_ 13 14#include <windows.h> 15 16#include "webrtc/base/constructormagic.h" 17#include "webrtc/typedefs.h" 18 19namespace webrtc { 20namespace win { 21 22// Scoper for GDI objects. 23template<class T, class Traits> 24class ScopedGDIObject { 25 public: 26 ScopedGDIObject() : handle_(NULL) {} 27 explicit ScopedGDIObject(T object) : handle_(object) {} 28 29 ~ScopedGDIObject() { 30 Traits::Close(handle_); 31 } 32 33 T Get() { 34 return handle_; 35 } 36 37 void Set(T object) { 38 if (handle_ && object != handle_) 39 Traits::Close(handle_); 40 handle_ = object; 41 } 42 43 ScopedGDIObject& operator=(T object) { 44 Set(object); 45 return *this; 46 } 47 48 T release() { 49 T object = handle_; 50 handle_ = NULL; 51 return object; 52 } 53 54 operator T() { return handle_; } 55 56 private: 57 T handle_; 58 59 DISALLOW_COPY_AND_ASSIGN(ScopedGDIObject); 60}; 61 62// The traits class that uses DeleteObject() to close a handle. 63template <typename T> 64class DeleteObjectTraits { 65 public: 66 // Closes the handle. 67 static void Close(T handle) { 68 if (handle) 69 DeleteObject(handle); 70 } 71 72 private: 73 DISALLOW_IMPLICIT_CONSTRUCTORS(DeleteObjectTraits); 74}; 75 76// The traits class that uses DestroyCursor() to close a handle. 77class DestroyCursorTraits { 78 public: 79 // Closes the handle. 80 static void Close(HCURSOR handle) { 81 if (handle) 82 DestroyCursor(handle); 83 } 84 85 private: 86 DISALLOW_IMPLICIT_CONSTRUCTORS(DestroyCursorTraits); 87}; 88 89typedef ScopedGDIObject<HBITMAP, DeleteObjectTraits<HBITMAP> > ScopedBitmap; 90typedef ScopedGDIObject<HCURSOR, DestroyCursorTraits> ScopedCursor; 91 92} // namespace win 93} // namespace webrtc 94 95#endif // WEBRTC_MODULES_DESKTOP_CAPTURE_WIN_SCOPED_GDI_HANDLE_H_ 96