fnv_1a_hash.h

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//    |  /           |
//    ' /   __| _` | __|  _ \   __|
//    . \  |   (   | |   (   |\__ `
//   _|\_\_|  \__,_|\__|\___/ ____/
//                   Multi-Physics
//
//  License:         BSD License
//                   Kratos default license:
// kratos/license.txt
//
//  Main authors:    Pooyan Dadvand
//                   Vicente Mataix Ferrandiz
//
//
 
#if !defined(KRATOS_FNV_1A_HASH_H_INCLUDED)
#define KRATOS_FNV_1A_HASH_H_INCLUDED
 
namespace Kratos {
 
class FNV1a32Hash {
 
public:
 
    typedef std::uint32_t HashType;
 
 
    FNV1a32Hash() = delete;
 
    virtual ~FNV1a32Hash() = delete;
 
    FNV1a32Hash &operator=(FNV1a32Hash const &rOther) = delete;
 
    FNV1a32Hash(FNV1a32Hash const &rOther) = delete;
 
 
    static constexpr HashType CalculateHash(const char *const TheString) {
        return CalculateHash(mFNV32OfsetBasis, TheString);
    }
 
 
    private:
 
    static constexpr HashType mFNV32OfsetBasis = 0x811c9dc5;
    static constexpr HashType mFNV32Prime = 0x1000193;
 
    static constexpr HashType CalculateHash(const HashType Value,
                                                const char *const TheString) {
        return (TheString[0] == '\0')
                ? Value
                : CalculateHash((Value ^ static_cast<HashType>(TheString[0])) * mFNV32Prime,
                                TheString + 1);
    }
 
 
}; // Class FNV1a32Hash
 
class FNV1a64Hash {
 
public:
 
    typedef std::uint64_t HashType;
 
 
    FNV1a64Hash() = delete;
 
    virtual ~FNV1a64Hash() = delete;
 
    FNV1a64Hash &operator=(FNV1a64Hash const &rOther) = delete;
 
    FNV1a64Hash(FNV1a64Hash const &rOther) = delete;
 
 
    static constexpr HashType CalculateHash(const char *const TheString) {
        return CalculateHash(mFNV64OfsetBasis, TheString);
    }
 
 
    private:
 
    static constexpr HashType mFNV64OfsetBasis = 0xcbf29ce484222325;
    static constexpr HashType mFNV64Prime = 0x100000001b3;
 
    static constexpr HashType CalculateHash(const HashType Value,
                                                const char *const TheString) {
        return (TheString[0] == '\0')
                ? Value
                : CalculateHash((Value ^ static_cast<HashType>(TheString[0])) * mFNV64Prime,
                                TheString + 1);
    }
 
 
}; // Class FNV1a64Hash
 
 
 
} // namespace Kratos.
 
#endif // KRATOS_FNV_1A_HASH_H_INCLUDED  defined