循环冗余校验（CRC）计算的C++代码
上⾯的代码可以⽤ git 下载。
这⾥把代码也贴了⼀份，⽅便不会使⽤ git 的同学下载。
#ifndef CRCCOMPUTE_H
#define CRCCOMPUTE_H
#include <stdint.h>
template <typename TYPE> class CRC
{
public:
CRC();
CRC(TYPE polynomial, TYPE init_remainder, TYPE final_xor_value);
void build(TYPE polynomial, TYPE init_remainder, TYPE final_xor_value);
/**
* Compute the CRC checksum of a binary message block.
* @para message, ⽤来计算的数据
* @para nBytes, 数据的长度
*/
TYPE crcCompute(char * message, unsigned int nBytes);
TYPE crcCompute(char * message, unsigned int nBytes, bool reinit);
protected:
TYPE m_polynomial;
TYPE m_initial_remainder;
TYPE m_final_xor_value;
TYPE m_remainder;
TYPE crcTable[256];
int m_width;
int m_topbit;
/**
* Initialize the CRC lookup table.
* This table is ud by crcCompute() to make CRC computation faster.
*/
void crcInit(void);
};
template <typename TYPE>
CRC<TYPE>::CRC()
{
m_width = 8 * sizeof(TYPE);
m_topbit = 1 << (m_width - 1);
}
template <typename TYPE>
CRC<TYPE>::CRC(TYPE polynomial, TYPE init_remainder, TYPE final_xor_value)
{
m_width = 8 * sizeof(TYPE);
感慨是什么意思m_topbit = 1 << (m_width - 1);
m_polynomial = polynomial;
m_initial_remainder = init_remainder;
m_final_xor_value = final_xor_value;
crcInit();
}
template <typename TYPE>
void CRC<TYPE>::build(TYPE polynomial, TYPE init_remainder, TYPE final_xor_value)
{
m_polynomial = polynomial;
m_initial_remainder = init_remainder;
m_final_xor_value = final_xor_value;
crcInit();
}
template <typename TYPE>
TYPE CRC<TYPE>::crcCompute(char * message, unsigned int nBytes)
{
unsigned int offt;
unsigned char byte;
TYPE remainder = m_initial_remainder;
/* Divide the message by the polynomial, a byte at a time. */
for( offt = 0; offt < nBytes; offt++)
{
byte = (remainder >> (m_width - 8)) ^ message[offt];
remainder = crcTable[byte] ^ (remainder << 8);
}
/* The final remainder is the CRC result. */
return (remainder ^ m_final_xor_value);
}
template <typename TYPE>
TYPE CRC<TYPE>::crcCompute(char * message, unsigned int nBytes, bool reinit)
{
unsigned int offt;
unsigned char byte;
if(reinit)
{
m_remainder = m_initial_remainder;
}
/* Divide the message by the polynomial, a byte at a time. */
for( offt = 0; offt < nBytes; offt++)
{
byte = (m_remainder >> (m_width - 8)) ^ message[offt];
m_remainder = crcTable[byte] ^ (m_remainder << 8);
}
/* The final remainder is the CRC result. */
return (m_remainder ^ m_final_xor_value);
}
zimmermannclass CRC8 : public CRC<uint8_t>
{
public:
enum CRC8_TYPE {eCRC8, eAUTOSAR, eCDMA2000, eDARC, eDVB_S2, eEBU, eAES, eGSM_A, eGSM_B, eI_CODE, eITU, eLTE, eMAXIM, eOPENSAFETY, eROHC, eSAE_J1850, eWCDMA};
CRC8(CRC8_TYPE type);
CRC8(uint8_t polynomial, uint8_t init_remainder, uint8_t final_xor_value)
:CRC<uint8_t>(polynomial, init_remainder, final_xor_value){}
preferences是什么意思
};
class CRC16 : public CRC<uint16_t>
{
public:
enum CRC16_TYPE {eCCITT, eKERMIT, eCCITT_FALSE, eIBM, eARC, eLHA, eSPI_FUJITSU,
eBUYPASS, eVERIFONE, eUMTS, eCDMA2000, eCMS, eDDS_110, eDECT_R,
eDECT_X, eDNP, eEN_13757, eGENIBUS, eEPC, eDARC, eI_CODE, eGSM,
eLJ1200, eMAXIM, eMCRF4XX, eOPENSAFETY_A, eOPENSAFETY_B, ePROFIBUS,
eIEC_61158_2, eRIELLO, eT10_DIF, eTELEDISK, eTMS37157, eUSB,
eCRC_A, eMODBUS, eX_25, eCRC_B, eISO_HDLC, eIBM_SDLC, eXMODEM,
eZMODEM, eACORN, eLTE};
CRC16(CRC16_TYPE type);
CRC16(uint16_t polynomial, uint16_t init_remainder, uint16_t final_xor_value)
:CRC<uint16_t>(polynomial, init_remainder, final_xor_value){}
};
class CRC32 : public CRC<uint32_t>
{
{
public:
enum CRC32_TYPE {eADCCP, ePKZIP, eCRC32, eAAL5, eDECT_B, eB_CRC32, eBZIP2, eAUTOSAR, eCRC32C, eCRC32D, eMPEG2, ePOSIX, eCKSUM, eCRC32Q, eJAMCRC, eXFER};
厦门英语
CRC32(CRC32_TYPE type);
};
#endif // CRCCOMPUTE_H
#include "crcCompute.h"
template <typename TYPE>
void CRC<TYPE>::crcInit(void)
{
TYPE remainder;
TYPE dividend;
int bit;
/* Perform binary long division, a bit at a time. */
for(dividend = 0; dividend < 256; dividend++)
{
/
* Initialize the remainder. */
remainder = dividend << (m_width - 8);
/* Shift and XOR with the polynomial. */
for(bit = 0; bit < 8; bit++)
{
/* Try to divide the current data bit. */
if(remainder & m_topbit)
{
remainder = (remainder << 1) ^ m_polynomial;
}
el
{
remainder = remainder << 1;
}
}
/* Save the result in the table. */
crcTable[dividend] = remainder;
}
}
CRC8::CRC8(CRC8_TYPE type)
{
switch (type)蓝色生死恋的插曲
{
ca eCRC8:
m_polynomial = 0x07; //reveng.sourceforge/crc-catalogue/all.htm
m_initial_remainder = 0x00;
m_final_xor_value = 0x00;
break;
ca eAUTOSAR:
m_polynomial = 0x2f;
m_initial_remainder = 0xff;
m_final_xor_value = 0xff;
break;
ca eCDMA2000:
m_polynomial = 0x9b;
m_initial_remainder = 0xFF;
琥珀教育m_final_xor_value = 0x00;
break;
ca eDARC:
m_polynomial = 0x39;
m_initial_remainder = 0x00;
m_final_xor_value = 0x00;
break;
ca eDVB_S2:
m_polynomial = 0xd5;
m_initial_remainder = 0x00; m_final_xor_value = 0x00;
break;
ca eEBU:
ca eAES:
m_polynomial = 0x1d;
m_initial_remainder = 0xFF; m_final_xor_value = 0x00;
break;
ca eGSM_A:
m_polynomial = 0x1d;
m_initial_remainder = 0x00; m_final_xor_value = 0x00;
break;
ca eGSM_B:
m_polynomial = 0x49;
m_initial_remainder = 0x00; m_final_xor_value = 0xFF;
break;
户口本翻译模板ca eI_CODE:
m_polynomial = 0x1d;
m_initial_remainder = 0xFD; m_final_xor_value = 0x00;
break;
ca eITU:
m_polynomial = 0x07;
m_initial_remainder = 0x00; m_final_xor_value = 0x55;
break;
ca eLTE:
m_polynomial = 0x9b;
m_initial_remainder = 0x00; m_final_xor_value = 0x00;
break;
ca eMAXIM:
m_polynomial = 0x31;
m_initial_remainder = 0x00; m_final_xor_value = 0x00;
break;
ca eOPENSAFETY:
m_polynomial = 0x2f;
m_initial_remainder = 0x00; m_final_xor_value = 0x00;
break;
ca eROHC:
m_polynomial = 0x07;
m_initial_remainder = 0xff; m_final_xor_value = 0x00;
break;
ca eSAE_J1850:
m_polynomial = 0x1d;
m_initial_remainder = 0xff; m_final_xor_value = 0xff;
break;
数学专业排名
ca eWCDMA:
m_polynomial = 0x9b;
m_initial_remainder = 0x00; m_final_xor_value = 0x00;
break;
default:
m_polynomial = 0x07;
m_initial_remainder = 0x00; m_final_xor_value = 0x00;
break;
break;
}
crcInit();
}
CRC16::CRC16(CRC16_TYPE type) {
switch (type)
{
ca eCCITT_FALSE:
ca eMCRF4XX:
m_polynomial = 0x1021;
m_initial_remainder = 0xFFFF; m_final_xor_value = 0x0000;
人工读音
break;
ca eIBM:
ca eARC:
ca eLHA:
ca eBUYPASS:
ca eVERIFONE:
ca eUMTS:
m_polynomial = 0x8005;
m_initial_remainder = 0x0000; m_final_xor_value = 0x0000;
break;
ca eSPI_FUJITSU:
m_polynomial = 0x1021;
m_initial_remainder = 0x1d0f; m_final_xor_value = 0x0000;
break;
avio
ca eCCITT:
ca eKERMIT:
ca eXMODEM:
ca eZMODEM:
ca eACORN:
ca eLTE:
m_polynomial = 0x1021;
m_initial_remainder = 0x0000; m_final_xor_value = 0x0000;
break;
ca eCDMA2000:
m_polynomial = 0xc867;
m_initial_remainder = 0xffff;
m_final_xor_value = 0x0000;
break;
ca eCMS:
ca eMODBUS:
m_polynomial = 0x8005;
m_initial_remainder = 0xffff;
m_final_xor_value = 0x0000;
break;
ca eDDS_110:
m_polynomial = 0x8005;
m_initial_remainder = 0x800d; m_final_xor_value = 0x0000;
break;
ca eDECT_R:
m_polynomial = 0x0589;
m_initial_remainder = 0x0000; m_final_xor_value = 0x0001;
break;
ca eDECT_X:
m_polynomial = 0x0589;
m_initial_remainder = 0x0000; m_final_xor_value = 0x0000;
