GFixedSizeHash.h

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#pragma once
 
namespace RE
{
    template <class T>
    class GFixedSizeHash
    {
    public:
        // http::/www.cs.yorku.ca/~oz/hash.html
        static inline UPInt SDBM_Hash(const void* a_dataIn, UPInt a_size, UPInt a_seed = 5381)
        {
            const std::uint8_t* data = static_cast<const std::uint8_t*>(a_dataIn);
            UPInt               hash = a_seed;
            while (a_size > 0) {
                hash = (hash << 16) + (hash << 6) - hash + static_cast<const UPInt>(data[a_size--]);
            }
            return hash;
        }
 
        UPInt operator()(const T& a_data) const
        {
            return SDBM_Hash(&a_data, sizeof(T));
        }
    };
    static_assert(sizeof(GFixedSizeHash<void*>) == 0x1);
}