C++ 分别实现CRC8,CRC16,CRC32校验数据

以下是C++实现CRC8、CRC16、CRC32校验数据的示例代码：

#include <iostream>
#include <cstring>

using namespace std;

// CRC8校验
uint8_t calc_crc8(uint8_t *data, uint32_t len)
{
    uint8_t crc = 0x00;
    uint8_t gen_poly = 0x07;
    for (uint32_t i = 0; i < len; i++)
    {
        crc ^= data[i];
        for (uint8_t j = 0; j < 8; j++)
        {
            if (crc & 0x80)
                crc = (crc << 1) ^ gen_poly;
            else
                crc <<= 1;
        }
    }
    return crc;
}

// CRC16校验
uint16_t calc_crc16(uint8_t *data, uint32_t len)
{
    uint16_t crc = 0xFFFF;
    uint16_t gen_poly = 0x1021;
    for (uint32_t i = 0; i < len; i++)
    {
        crc ^= (uint16_t)data[i] << 8;
        for (uint8_t j = 0; j < 8; j++)
        {
            if (crc & 0x8000)
                crc = (crc << 1) ^ gen_poly;
            else
                crc <<= 1;
        }
    }
    return crc;
}

// CRC32校验
uint32_t calc_crc32(uint8_t *data, uint32_t len)
{
    uint32_t crc = 0xFFFFFFFF;
    uint32_t gen_poly = 0xEDB88320;
    for (uint32_t i = 0; i < len; i++)
    {
        crc ^= data[i];
        for (uint8_t j = 0; j < 8; j++)
        {
            if (crc & 0x00000001)
                crc = (crc >> 1) ^ gen_poly;
            else
                crc >>= 1;
        }
    }
    return ~crc;
}

int main()
{
    // 测试数据
    uint8_t data[] = {0x01, 0x02, 0x03, 0x04, 0x05};
    uint32_t len = sizeof(data);

    // CRC8校验
    uint8_t crc8 = calc_crc8(data, len);
    cout << "CRC8: 0x" << hex << (int)crc8 << endl;

    // CRC16校验
    uint16_t crc16 = calc_crc16(data, len);
    cout << "CRC16: 0x" << hex << crc16 << endl;

    // CRC32校验
    uint32_t crc32 = calc_crc32(data, len);
    cout << "CRC32: 0x" << hex << crc32 << endl;

    return 0;
}

注意，以上示例代码仅为演示CRC校验算法的实现，实际应用中可能需要对输入数据进行预处理（如填充、反转、异或等）以满足特定的校验需求。