1/*
2 * Copyright (C) 2012 Apple 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 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 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 BitArray_h
27#define BitArray_h
28
29#include <string.h>
30#include "wtf/Assertions.h"
31
32namespace WTF {
33
34template<unsigned arraySize>
35class BitArray {
36public:
37    BitArray(bool value = false)
38    {
39        memset(m_data, value ? 0xFF : 0, sizeof(m_data));
40    }
41
42    void set(unsigned index)
43    {
44        ASSERT_WITH_SECURITY_IMPLICATION(index < arraySize);
45        m_data[index / 8] |= 1 << (index & 7);
46    }
47
48    void clear(unsigned index)
49    {
50        ASSERT_WITH_SECURITY_IMPLICATION(index < arraySize);
51        m_data[index / 8] &= ~(1 << (index & 7));
52    }
53
54    bool get(unsigned index) const
55    {
56        ASSERT_WITH_SECURITY_IMPLICATION(index < arraySize);
57        return !!(m_data[index / 8] & (1 << (index & 7)));
58    }
59
60private:
61    unsigned char m_data[arraySize / 8 + 1];
62};
63
64} // namespace WTF
65
66using WTF::BitArray;
67
68#endif // BitArray_h
69