Files
Xenia-Canary/src/xenia/base/bit_map.h
2015-12-29 13:09:58 -08:00

56 lines
1.6 KiB
C++

/**
******************************************************************************
* Xenia : Xbox 360 Emulator Research Project *
******************************************************************************
* Copyright 2015 Ben Vanik. All rights reserved. *
* Released under the BSD license - see LICENSE in the root for more details. *
******************************************************************************
*/
#ifndef XENIA_BASE_BIT_MAP_H_
#define XENIA_BASE_BIT_MAP_H_
#include <cstdint>
#include <vector>
namespace xe {
// Bit Map: Efficient lookup of free/used entries.
class BitMap {
public:
BitMap();
// Size is the number of 8-bit entries, must be a multiple of 4.
BitMap(size_t size);
// Data does not have to be aligned to a 4-byte boundary, but it is
// preferable.
// Size is the number of 8-bit entries, must be a multiple of 4.
BitMap(uint32_t* data, size_t size);
// (threadsafe) Acquires an entry and returns its index. Returns -1 if there
// are no more free entries.
size_t Acquire();
// (threadsafe) Releases an entry by an index.
void Release(size_t index);
// Resize the bitmap. Size is the number of 8-bit entries, must be a multiple
// of 4.
void Resize(size_t new_size);
// Sets all entries to free.
void Reset();
const std::vector<uint32_t> data() const { return data_; }
std::vector<uint32_t>& data() { return data_; }
private:
const static uint32_t kDataSize = 4;
const static uint32_t kDataSizeBits = kDataSize * 8;
std::vector<uint32_t> data_;
};
} // namespace xe
#endif // XENIA_BASE_BIT_MAP_H_