CRC.hpp

[詳解]

//
//    CRC
//
//    Copyright (c) 2022-2024 udonrobo
//
 
#pragma once
 
#include <Udon/Types/ArrayView.hpp>
 
namespace Udon
{
    constexpr size_t CRC8_SIZE = 1;
 
    inline uint8_t CRC8(ArrayView<const uint8_t> buffer)
    {
        uint8_t crc = 0xFF;    // initial value
 
        for (const auto& it : buffer)
        {
            crc ^= it;
 
            for (uint8_t bit = 0; bit < 8 /* CHAR_BIT */; ++bit)
            {
                if (crc & 0x80)
                {
                    crc = (crc << 1) ^ 0x1D;    // polynomial
                }
                else
                {
                    crc <<= 1;
                }
            }
        }
 
        return crc ^ 0xFF;    // final XOR
    }
 
}    // namespace Udon