ByteSwapper

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namespace {

#include <stdint-gcc.h>

    inline uint16_t ByteSwap2(uint16_t inData) {
        return (inData >> 8) | (inData << 8);
    }

    inline uint32_t ByteSwap4(uint32_t inData) {
        return ((inData >> 24) & 0x000000ff)
               | ((inData >> 8) & 0x0000ff00)
               | ((inData << 8) & 0x00ff0000)
               | ((inData << 24) & 0xff000000);
    }

    inline uint64_t ByteSwap8(uint64_t inData) {
        return ((inData >> 56) & 0xff)
               | ((inData >> 40) & 0xff00)
               | ((inData >> 24) & 0xff0000)
               | ((inData >> 8) & 0xff000000)
               | ((inData << 8) & 0xff00000000)
               | ((inData << 24) & 0xff0000000000)
               | ((inData << 40) & 0xff000000000000)
               | ((inData << 56) & 0xff00000000000000);
    }

    template<typename tFrom, typename tTo>
    class TypeAliaser {
    public:
        TypeAliaser(tFrom inFromValue) : _asFromType(inFromValue) {}

        tTo &Get() { return _asToType; }

    private:
        union {
            tFrom _asFromType;
            tTo _asToType;
        };
    };


    template<typename T, unsigned long>
    class ByteSwapper;

    template<typename T>
    class ByteSwapper<T, 2> {
    public:
        static T Swap(T inData) {
            auto result = ByteSwap2(TypeAliaser<T, uint16_t>(inData).Get());
            return TypeAliaser<uint16_t, T>(result).Get();
        }
    };

    template<typename T>
    class ByteSwapper<T, 4> {
    public:
        static T Swap(T inData) {
            auto result = ByteSwap4(TypeAliaser<T, uint32_t>(inData).Get());
            return TypeAliaser<uint32_t, T>(result).Get();
        }
    };

    template<typename T>
    class ByteSwapper<T, 8> {
    public:
        static T Swap(T inData) {
            auto result = ByteSwap8(TypeAliaser<T, uint64_t>(inData).Get());
            return TypeAliaser<uint64_t, T>(result).Get();
        }
    };
}

template<typename T>
inline T ByteSwap(T inData) {
    return ByteSwapper<T, sizeof(T)>::Swap(inData);
}