serial_number.hpp

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#ifndef SERIAL_NUMBER_HPP_
#define SERIAL_NUMBER_HPP_

#include "openthread-core-config.h"

#include <stdint.h>

#include "common/numeric_limits.hpp"
#include "common/type_traits.hpp"

namespace ot {

class SerialNumber
{
public:
    template <typename UintType> static bool IsLess(UintType aFirst, UintType aSecond)
    {
        static_assert(TypeTraits::IsSame<UintType, uint8_t>::kValue || TypeTraits::IsSame<UintType, uint16_t>::kValue ||
                          TypeTraits::IsSame<UintType, uint32_t>::kValue ||
                          TypeTraits::IsSame<UintType, uint64_t>::kValue,
                      "UintType MUST be an 8, 16, 32, or 64 bit `uint` type");

        static constexpr UintType kNegativeMask = (NumericLimits<UintType>::kMax >> 1) + 1;

        return ((aFirst - aSecond) & kNegativeMask) != 0;
    }

    template <typename UintType> static bool IsGreater(UintType aFirst, UintType aSecond)
    {
        return IsLess(aSecond, aFirst);
    }
};

} // namespace ot

#endif // SERIAL_NUMBER_HPP_