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
32namespace WebCore {
33
34class HWndDC {
35    WTF_MAKE_NONCOPYABLE(HWndDC);
36public:
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
82private:
83    HWND m_hwnd;
84    HDC m_hdc;
85};
86
87} // namespace WebCore
88
89#endif // HWndDC_h
90