1
2/*
3 * Copyright 2011 Google Inc.
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9
10#include "SkBitSet.h"
11
12SkBitSet::SkBitSet(int numberOfBits)
13    : fBitData(NULL), fDwordCount(0), fBitCount(numberOfBits) {
14    SkASSERT(numberOfBits > 0);
15    // Round up size to 32-bit boundary.
16    fDwordCount = (numberOfBits + 31) / 32;
17    fBitData.set(malloc(fDwordCount * sizeof(uint32_t)));
18    clearAll();
19}
20
21SkBitSet::SkBitSet(const SkBitSet& source)
22    : fBitData(NULL), fDwordCount(0), fBitCount(0) {
23    *this = source;
24}
25
26SkBitSet& SkBitSet::operator=(const SkBitSet& rhs) {
27    if (this == &rhs) {
28        return *this;
29    }
30    fBitCount = rhs.fBitCount;
31    fBitData.free();
32    fDwordCount = rhs.fDwordCount;
33    fBitData.set(malloc(fDwordCount * sizeof(uint32_t)));
34    memcpy(fBitData.get(), rhs.fBitData.get(), fDwordCount * sizeof(uint32_t));
35    return *this;
36}
37
38bool SkBitSet::operator==(const SkBitSet& rhs) {
39    if (fBitCount == rhs.fBitCount) {
40        if (fBitData.get() != NULL) {
41            return (memcmp(fBitData.get(), rhs.fBitData.get(),
42                           fDwordCount * sizeof(uint32_t)) == 0);
43        }
44        return true;
45    }
46    return false;
47}
48
49bool SkBitSet::operator!=(const SkBitSet& rhs) {
50    return !(*this == rhs);
51}
52
53void SkBitSet::clearAll() {
54    if (fBitData.get() != NULL) {
55        sk_bzero(fBitData.get(), fDwordCount * sizeof(uint32_t));
56    }
57}
58
59void SkBitSet::setBit(int index, bool value) {
60    uint32_t mask = 1 << (index % 32);
61    if (value) {
62        *(internalGet(index)) |= mask;
63    } else {
64        *(internalGet(index)) &= ~mask;
65    }
66}
67
68bool SkBitSet::isBitSet(int index) const {
69    uint32_t mask = 1 << (index % 32);
70    return 0 != (*internalGet(index) & mask);
71}
72
73bool SkBitSet::orBits(const SkBitSet& source) {
74    if (fBitCount != source.fBitCount) {
75        return false;
76    }
77    uint32_t* targetBitmap = internalGet(0);
78    uint32_t* sourceBitmap = source.internalGet(0);
79    for (size_t i = 0; i < fDwordCount; ++i) {
80        targetBitmap[i] |= sourceBitmap[i];
81    }
82    return true;
83}
84