1// Copyright (C) 2013 Google Inc. All rights reserved.
2//
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4// modification, are permitted provided that the following conditions are
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28
29#ifndef GraphicsContextStateSaver_h
30#define GraphicsContextStateSaver_h
31
32#include "platform/PlatformExport.h"
33#include "platform/graphics/GraphicsContext.h"
34
35namespace blink {
36
37class PLATFORM_EXPORT GraphicsContextStateSaver {
38    WTF_MAKE_FAST_ALLOCATED;
39public:
40    GraphicsContextStateSaver(GraphicsContext& context, bool saveAndRestore = true)
41        : m_context(context)
42        , m_saveAndRestore(saveAndRestore)
43    {
44        if (m_saveAndRestore)
45            m_context.save();
46    }
47
48    ~GraphicsContextStateSaver()
49    {
50        if (m_saveAndRestore)
51            m_context.restore();
52    }
53
54    void save()
55    {
56        ASSERT(!m_saveAndRestore);
57        m_context.save();
58        m_saveAndRestore = true;
59    }
60
61    void saveIfNeeded()
62    {
63        if (saved())
64            return;
65        save();
66    }
67
68    void restore()
69    {
70        ASSERT(m_saveAndRestore);
71        m_context.restore();
72        m_saveAndRestore = false;
73    }
74
75    GraphicsContext* context() const { return &m_context; }
76    bool saved() const { return m_saveAndRestore; }
77
78private:
79    GraphicsContext& m_context;
80    bool m_saveAndRestore;
81};
82
83} // namespace blink
84
85#endif // GraphicsContextStateSaver_h
86