bloom_filter.h

#ifndef CACHEMERE_BLOOM_FILTER_H
#define CACHEMERE_BLOOM_FILTER_H
 
#include <cstdint>
#include <functional>
#include <random>
 
#ifdef _WIN32
#    pragma warning(push)
#    pragma warning(disable : 4244)
#    pragma warning(disable : 4018)
#endif
 
#include <boost/dynamic_bitset.hpp>
 
#ifdef _WIN32
#    pragma warning(pop)
#endif
 
#include "hash_mixer.h"
 
namespace cachemere::policy::detail {
 
template<typename ItemHash> class BloomFilter
{
public:
    BloomFilter(uint32_t cardinality);
 
    template<typename ItemKey> void add(const ItemKey& item);
 
    void clear();
 
    template<typename ItemKey> [[nodiscard]] bool maybe_contains(const ItemKey& item) const;
 
    [[nodiscard]] size_t memory_used() const noexcept;
 
    [[nodiscard]] double saturation() const noexcept;
 
private:
    using BitsetBlock = uint8_t;
    using BitSet      = boost::dynamic_bitset<BitsetBlock>;
 
    uint32_t m_cardinality;
    BitSet   m_filter;
    uint32_t m_nb_hashes;
};
 
}  // namespace cachemere::policy::detail
 
#include "bloom_filter.hpp"
 
#endif