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      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 
     12 SkBitSet::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 
     21 SkBitSet::SkBitSet(const SkBitSet& source)
     22     : fBitData(NULL), fDwordCount(0), fBitCount(0) {
     23     *this = source;
     24 }
     25 
     26 SkBitSet& 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 
     38 bool 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 
     49 bool SkBitSet::operator!=(const SkBitSet& rhs) {
     50     return !(*this == rhs);
     51 }
     52 
     53 void SkBitSet::clearAll() {
     54     if (fBitData.get() != NULL) {
     55         sk_bzero(fBitData.get(), fDwordCount * sizeof(uint32_t));
     56     }
     57 }
     58 
     59 void 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 
     68 bool SkBitSet::isBitSet(int index) const {
     69     uint32_t mask = 1 << (index % 32);
     70     return 0 != (*internalGet(index) & mask);
     71 }
     72 
     73 bool 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