1 /* 2 * Copyright (C) 2012 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #ifndef HWndDC_h 27 #define HWndDC_h 28 29 #include <windows.h> 30 #include "wtf/NonCopyable.h" 31 32 namespace blink { 33 34 class HWndDC { 35 WTF_MAKE_NONCOPYABLE(HWndDC); 36 public: 37 HWndDC() 38 : m_hwnd(0) 39 , m_hdc(0) 40 { 41 } 42 43 explicit HWndDC(HWND hwnd) 44 : m_hwnd(hwnd) 45 , m_hdc(::GetDC(hwnd)) 46 { 47 } 48 49 HWndDC(HWND hwnd, HRGN hrgnClip, DWORD flags) 50 : m_hwnd(hwnd) 51 , m_hdc(::GetDCEx(hwnd, hrgnClip, flags)) 52 { 53 } 54 55 ~HWndDC() 56 { 57 clear(); 58 } 59 60 HDC setHWnd(HWND hwnd) 61 { 62 clear(); 63 m_hwnd = hwnd; 64 m_hdc = ::GetDC(hwnd); 65 return m_hdc; 66 } 67 68 void clear() 69 { 70 if (!m_hdc) 71 return; 72 ::ReleaseDC(m_hwnd, m_hdc); 73 m_hwnd = 0; 74 m_hdc = 0; 75 } 76 77 operator HDC() 78 { 79 return m_hdc; 80 } 81 82 private: 83 HWND m_hwnd; 84 HDC m_hdc; 85 }; 86 87 } // namespace blink 88 89 #endif // HWndDC_h 90