1/*
2 * Copyright (C) 2009 Apple Inc. All rights reserved.
3 * Copyright (C) 2013 Google Inc. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
17 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
18 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
21 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
22 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#ifndef ArrayBufferContents_h
28#define ArrayBufferContents_h
29
30#include "wtf/ArrayBufferDeallocationObserver.h"
31#include "wtf/Noncopyable.h"
32#include "wtf/WTFExport.h"
33
34namespace WTF {
35
36class WTF_EXPORT ArrayBufferContents {
37    WTF_MAKE_NONCOPYABLE(ArrayBufferContents);
38public:
39    enum InitializationPolicy {
40        ZeroInitialize,
41        DontInitialize
42    };
43
44    ArrayBufferContents();
45    ArrayBufferContents(unsigned numElements, unsigned elementByteSize, ArrayBufferContents::InitializationPolicy);
46
47    // Use with care. data must be allocated with allocateMemory.
48    // ArrayBufferContents will take ownership of the data and free it (using freeMemorY)
49    // upon destruction.
50    // This constructor will not call observer->StartObserving(), so it is a responsibility
51    // of the caller to make sure JS knows about external memory.
52    ArrayBufferContents(void* data, unsigned sizeInBytes, ArrayBufferDeallocationObserver*);
53
54    ~ArrayBufferContents();
55
56    void clear();
57
58    void* data() const { return m_data; }
59    unsigned sizeInBytes() const { return m_sizeInBytes; }
60
61    void setDeallocationObserver(ArrayBufferDeallocationObserver* observer)
62    {
63        if (!m_deallocationObserver) {
64            m_deallocationObserver = observer;
65            m_deallocationObserver->blinkAllocatedMemory(m_sizeInBytes);
66        }
67    }
68
69    void transfer(ArrayBufferContents& other);
70    void copyTo(ArrayBufferContents& other);
71
72    static void allocateMemory(size_t, InitializationPolicy, void*&);
73    static void freeMemory(void*, size_t);
74
75private:
76    void* m_data;
77    unsigned m_sizeInBytes;
78    ArrayBufferDeallocationObserver* m_deallocationObserver;
79};
80
81} // namespace WTF
82
83#endif // ArrayBufferContents_h
84