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- /*
- * Copyright 2011 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
- #ifndef SkBitSet_DEFINED
- #define SkBitSet_DEFINED
- #include "include/private/SkTemplates.h"
- class SkBitSet {
- public:
- explicit SkBitSet(int numberOfBits) {
- SkASSERT(numberOfBits >= 0);
- fDwordCount = (numberOfBits + 31) / 32; // Round up size to 32-bit boundary.
- if (fDwordCount > 0) {
- fBitData.reset((uint32_t*)sk_calloc_throw(fDwordCount * sizeof(uint32_t)));
- }
- }
- /** Set the value of the index-th bit to true. */
- void set(int index) {
- uint32_t mask = 1 << (index & 31);
- uint32_t* chunk = this->internalGet(index);
- SkASSERT(chunk);
- *chunk |= mask;
- }
- bool has(int index) const {
- const uint32_t* chunk = this->internalGet(index);
- uint32_t mask = 1 << (index & 31);
- return chunk && SkToBool(*chunk & mask);
- }
- // Calls f(unsigned) for each set value.
- template<typename FN>
- void getSetValues(FN f) const {
- const uint32_t* data = fBitData.get();
- for (unsigned i = 0; i < fDwordCount; ++i) {
- if (uint32_t value = data[i]) { // There are set bits
- unsigned index = i * 32;
- for (unsigned j = 0; j < 32; ++j) {
- if (0x1 & (value >> j)) {
- f(index | j);
- }
- }
- }
- }
- }
- private:
- std::unique_ptr<uint32_t, SkFunctionWrapper<void, void, sk_free>> fBitData;
- size_t fDwordCount; // Dword (32-bit) count of the bitset.
- uint32_t* internalGet(int index) const {
- size_t internalIndex = index / 32;
- if (internalIndex >= fDwordCount) {
- return nullptr;
- }
- return fBitData.get() + internalIndex;
- }
- };
- #endif
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