CRC 8-ми битных чисел

//------------------------------------------------------------------------------
#ifndef CS_H
#define CS_H
//------------------------------------------------------------------------------
#include <iostream>
//------------------------------------------------------------------------------
//lrc = -( (c[0] + c[1] + ... + c[n]) % 256 )
unsigned char lrc_modicon
(
    unsigned char *puchMsg, /* message to calculate LRC upon */
    unsigned long usDataLen /* quantity of bytes in message */
);
 
//lrc = (c[0] + c[1] + ... + c[n]) % 256
unsigned char lrc_icp_das
(
    unsigned char *message,
    unsigned long sizeof_message
);
 
unsigned char lrc_volmag
(
    unsigned char *message,
    unsigned long sizeof_message
);
 
//IBM, 0x8005, x16 + x15 + x2 + 1
unsigned short crc16_ibm
(
    unsigned char *puchMsg, /* message to calculate CRC upon */
    unsigned long usDataLen /* quantity of bytes in message */
);
 
//CCITT, 0x1021, x16 + x12 + x5 + 1
unsigned short crc16_ccitt
(
    unsigned char *message,
    unsigned long sizeof_message
);
//------------------------------------------------------------------------------
void set_lrc_modicon(unsigned char * const res);
void update_lrc_modicon(unsigned char * const res, const unsigned char c);
void get_lrc_modicon(unsigned char * const res);
 
void set_lrc_icp_das(unsigned char * const res);
void update_lrc_icp_das(unsigned char * const res, const unsigned char c);
void get_lrc_icp_das(unsigned char * const res);
 
void set_lrc_volmag(unsigned char * const res);
void update_lrc_volmag(unsigned char * const res, const unsigned char c);
void get_lrc_volmag(unsigned char * const res);
 
void set_crc16_ibm(unsigned short * const res);
void update_crc16_ibm(unsigned short * const res, const unsigned char c);
void get_crc16_ibm(unsigned short * const res);
 
void set_crc16_ccitt(unsigned short * const res);
void update_crc16_ccitt(unsigned short * const res, const unsigned char c);
void get_crc16_ccitt(unsigned short * const res);
//------------------------------------------------------------------------------
unsigned char lrc_modicon(std::istream &is);
unsigned char lrc_icp_das(std::istream &is);
unsigned char lrc_volmag(std::istream &is);
unsigned short crc16_ibm(std::istream &is);
unsigned short crc16_ccitt(std::istream &is);
//------------------------------------------------------------------------------
#endif //CS_H

//------------------------------------------------------------------------------
#include "cs.h"
//==============================================================================
//lrc = -( (c[0] + c[1] + ... + c[n]) % 256 )
unsigned char lrc_modicon
(
    unsigned char *puchMsg, /* message to calculate LRC upon */
    unsigned long usDataLen /* quantity of bytes in message */
)
{
    unsigned char uchLRC = 0; /* LRC char initialized */
 
    for(unsigned long i = 0; i < usDataLen; i++)
        uchLRC += *puchMsg++; /* add buffer byte without carry */
 
    return -uchLRC; /* return twos complement */
}
//------------------------------------------------------------------------------
//lrc = (c[0] + c[1] + ... + c[n]) % 256
unsigned char lrc_icp_das
(
    unsigned char *message,
    unsigned long sizeof_message
)
{
    unsigned char res = 0;
 
    for(unsigned long i = 0; i < sizeof_message; i++)
        res += *message++;
 
    return res;
}
//------------------------------------------------------------------------------
unsigned char lrc_volmag
(
    unsigned char *message,
    unsigned long sizeof_message
)
{
    int res = 0;
 
    for(unsigned long i = 0; i < sizeof_message; i++)
    {
        res += *message++;
        if (res > 255) res -= 255;
    }
    
    return -res;
}
//==============================================================================
/* Table of CRC values for low–order byte */
static const unsigned char auchCRCLo[] = {
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81,
0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,
0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01,
0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81,
0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0,
0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01,
0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81,
0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,
0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01,
0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81,
0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,
0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01,
0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81,
0x40
};
//------------------------------------------------------------------------------
/* Table of CRC values for high–order byte */
static const char auchCRCHi[] = {
0x00, 0xC0, 0xC1, 0x01, 0xC3, 0x03, 0x02, 0xC2, 0xC6, 0x06, 0x07, 0xC7, 0x05, 0xC5, 0xC4,
0x04, 0xCC, 0x0C, 0x0D, 0xCD, 0x0F, 0xCF, 0xCE, 0x0E, 0x0A, 0xCA, 0xCB, 0x0B, 0xC9, 0x09,
0x08, 0xC8, 0xD8, 0x18, 0x19, 0xD9, 0x1B, 0xDB, 0xDA, 0x1A, 0x1E, 0xDE, 0xDF, 0x1F, 0xDD,
0x1D, 0x1C, 0xDC, 0x14, 0xD4, 0xD5, 0x15, 0xD7, 0x17, 0x16, 0xD6, 0xD2, 0x12, 0x13, 0xD3,
0x11, 0xD1, 0xD0, 0x10, 0xF0, 0x30, 0x31, 0xF1, 0x33, 0xF3, 0xF2, 0x32, 0x36, 0xF6, 0xF7,
0x37, 0xF5, 0x35, 0x34, 0xF4, 0x3C, 0xFC, 0xFD, 0x3D, 0xFF, 0x3F, 0x3E, 0xFE, 0xFA, 0x3A,
0x3B, 0xFB, 0x39, 0xF9, 0xF8, 0x38, 0x28, 0xE8, 0xE9, 0x29, 0xEB, 0x2B, 0x2A, 0xEA, 0xEE,
0x2E, 0x2F, 0xEF, 0x2D, 0xED, 0xEC, 0x2C, 0xE4, 0x24, 0x25, 0xE5, 0x27, 0xE7, 0xE6, 0x26,
0x22, 0xE2, 0xE3, 0x23, 0xE1, 0x21, 0x20, 0xE0, 0xA0, 0x60, 0x61, 0xA1, 0x63, 0xA3, 0xA2,
0x62, 0x66, 0xA6, 0xA7, 0x67, 0xA5, 0x65, 0x64, 0xA4, 0x6C, 0xAC, 0xAD, 0x6D, 0xAF, 0x6F,
0x6E, 0xAE, 0xAA, 0x6A, 0x6B, 0xAB, 0x69, 0xA9, 0xA8, 0x68, 0x78, 0xB8, 0xB9, 0x79, 0xBB,
0x7B, 0x7A, 0xBA, 0xBE, 0x7E, 0x7F, 0xBF, 0x7D, 0xBD, 0xBC, 0x7C, 0xB4, 0x74, 0x75, 0xB5,
0x77, 0xB7, 0xB6, 0x76, 0x72, 0xB2, 0xB3, 0x73, 0xB1, 0x71, 0x70, 0xB0, 0x50, 0x90, 0x91,
0x51, 0x93, 0x53, 0x52, 0x92, 0x96, 0x56, 0x57, 0x97, 0x55, 0x95, 0x94, 0x54, 0x9C, 0x5C,
0x5D, 0x9D, 0x5F, 0x9F, 0x9E, 0x5E, 0x5A, 0x9A, 0x9B, 0x5B, 0x99, 0x59, 0x58, 0x98, 0x88,
0x48, 0x49, 0x89, 0x4B, 0x8B, 0x8A, 0x4A, 0x4E, 0x8E, 0x8F, 0x4F, 0x8D, 0x4D, 0x4C, 0x8C,
0x44, 0x84, 0x85, 0x45, 0x87, 0x47, 0x46, 0x86, 0x82, 0x42, 0x43, 0x83, 0x41, 0x81, 0x80,
0x40
};
//------------------------------------------------------------------------------
//IBM, 0x8005, x16 + x15 + x2 + 1
unsigned short crc16_ibm
(
    unsigned char *puchMsg, /* message to calculate CRC upon */
    unsigned long usDataLen /* quantity of bytes in message */
)
{
    unsigned char uchCRCLo = 0xFF; /* low byte of CRC initialized */
    unsigned char uchCRCHi = 0xFF; /* high byte of CRC initialized */
    unsigned long uIndex; /* will index into CRC lookup table */
 
    for(unsigned long i = 0; i < usDataLen; i++)
    {
        uIndex = uchCRCLo ^ *puchMsg++; /* calculate the CRC */
        uchCRCLo = uchCRCHi ^ auchCRCLo[uIndex];
        uchCRCHi = auchCRCHi[uIndex];
    }
 
    return (uchCRCHi << 8 | uchCRCLo);
}
//==============================================================================
static unsigned short crc16_ccitt_c[256] =
{
    0x0000, 0x2110, 0x4220, 0x6330, 0x8440, 0xa550, 0xc660, 0xe770,
    0x0881, 0x2991, 0x4aa1, 0x6bb1, 0x8cc1, 0xadd1, 0xcee1, 0xeff1,
    0x3112, 0x1002, 0x7332, 0x5222, 0xb552, 0x9442, 0xf772, 0xd662,
    0x3993, 0x1883, 0x7bb3, 0x5aa3, 0xbdd3, 0x9cc3, 0xfff3, 0xdee3, 
    0x6224, 0x4334, 0x2004, 0x0114, 0xe664, 0xc774, 0xa444, 0x8554, 
    0x6aa5, 0x4bb5, 0x2885, 0x0995, 0xeee5, 0xcff5, 0xacc5, 0x8dd5, 
    0x5336, 0x7226, 0x1116, 0x3006, 0xd776, 0xf666, 0x9556, 0xb446, 
    0x5bb7, 0x7aa7, 0x1997, 0x3887, 0xdff7, 0xfee7, 0x9dd7, 0xbcc7, 
    0xc448, 0xe558, 0x8668, 0xa778, 0x4008, 0x6118, 0x0228, 0x2338, 
    0xccc9, 0xedd9, 0x8ee9, 0xaff9, 0x4889, 0x6999, 0x0aa9, 0x2bb9, 
    0xf55a, 0xd44a, 0xb77a, 0x966a, 0x711a, 0x500a, 0x333a, 0x122a, 
    0xfddb, 0xdccb, 0xbffb, 0x9eeb, 0x799b, 0x588b, 0x3bbb, 0x1aab, 
    0xa66c, 0x877c, 0xe44c, 0xc55c, 0x222c, 0x033c, 0x600c, 0x411c, 
    0xaeed, 0x8ffd, 0xeccd, 0xcddd, 0x2aad, 0x0bbd, 0x688d, 0x499d, 
    0x977e, 0xb66e, 0xd55e, 0xf44e, 0x133e, 0x322e, 0x511e, 0x700e, 
    0x9fff, 0xbeef, 0xdddf, 0xfccf, 0x1bbf, 0x3aaf, 0x599f, 0x788f,
    0x8891, 0xa981, 0xcab1, 0xeba1, 0x0cd1, 0x2dc1, 0x4ef1, 0x6fe1, 
    0x8010, 0xa100, 0xc230, 0xe320, 0x0450, 0x2540, 0x4670, 0x6760,
    0xb983, 0x9893, 0xfba3, 0xdab3, 0x3dc3, 0x1cd3, 0x7fe3, 0x5ef3, 
    0xb102, 0x9012, 0xf322, 0xd232, 0x3542, 0x1452, 0x7762, 0x5672, 
    0xeab5, 0xcba5, 0xa895, 0x8985, 0x6ef5, 0x4fe5, 0x2cd5, 0x0dc5, 
    0xe234, 0xc324, 0xa014, 0x8104, 0x6674, 0x4764, 0x2454, 0x0544, 
    0xdba7, 0xfab7, 0x9987, 0xb897, 0x5fe7, 0x7ef7, 0x1dc7, 0x3cd7, 
    0xd326, 0xf236, 0x9106, 0xb016, 0x5766, 0x7676, 0x1546, 0x3456, 
    0x4cd9, 0x6dc9, 0x0ef9, 0x2fe9, 0xc899, 0xe989, 0x8ab9, 0xaba9, 
    0x4458, 0x6548, 0x0678, 0x2768, 0xc018, 0xe108, 0x8238, 0xa328, 
    0x7dcb, 0x5cdb, 0x3feb, 0x1efb, 0xf98b, 0xd89b, 0xbbab, 0x9abb, 
    0x754a, 0x545a, 0x376a, 0x167a, 0xf10a, 0xd01a, 0xb32a, 0x923a,
    0x2efd, 0x0fed, 0x6cdd, 0x4dcd, 0xaabd, 0x8bad, 0xe89d, 0xc98d, 
    0x267c, 0x076c, 0x645c, 0x454c, 0xa23c, 0x832c, 0xe01c, 0xc10c, 
    0x1fef, 0x3eff, 0x5dcf, 0x7cdf, 0x9baf, 0xbabf, 0xd98f, 0xf89f,
    0x176e, 0x367e, 0x554e, 0x745e, 0x932e, 0xb23e, 0xd10e, 0xf01e 
};
//------------------------------------------------------------------------------
//CCITT, 0x1021, x16 + x12 + x5 + 1
unsigned short crc16_ccitt
(
    unsigned char *message,
    unsigned long sizeof_message
)
{
    unsigned short res = 0;
 
    for(unsigned long i = 0; i < sizeof_message; i++)
    {
        res ^= message[i];
        res = (res >> 8) ^ crc16_ccitt_c[res & 0xFF];
    }
 
    return res;
}
//==============================================================================
void set_lrc_modicon(unsigned char * const res)
{
    *res = 0;
}
//------------------------------------------------------------------------------
void update_lrc_modicon(unsigned char * const res, const unsigned char c)
{
    *res += c;
}
//------------------------------------------------------------------------------
void get_lrc_modicon(unsigned char * const res)
{
    *res = -*res;
}
//==============================================================================
void set_lrc_icp_das(unsigned char * const res)
{
    *res = 0;
}
//------------------------------------------------------------------------------
void update_lrc_icp_das(unsigned char * const res, const unsigned char c)
{
    *res += c;
}
//------------------------------------------------------------------------------
void get_lrc_icp_das(unsigned char * const res)
{}
//==============================================================================
void set_lrc_volmag(unsigned char * const res)
{
    *res = 0;
}
//------------------------------------------------------------------------------
void update_lrc_volmag(unsigned char * const res, const unsigned char c)
{
    int s = 0;
    *(unsigned char *)&s = *res;
    s += c;
    if (s > 255) s -= 255;
    *res = *(unsigned char *)&s;
}
//------------------------------------------------------------------------------
void get_lrc_volmag(unsigned char * const res)
{
    int s = 0;
    *(unsigned char *)&s = *res;
    *res = -s;
}
//==============================================================================
void set_crc16_ibm(unsigned short * const res)
{
    *res = 0xFFFF;
}
//------------------------------------------------------------------------------
void update_crc16_ibm(unsigned short * const res, const unsigned char c)
{
    unsigned char *res_lo = (unsigned char *)res;
    unsigned char *res_hi = (unsigned char *)res + 1;
    unsigned long index = *res_lo ^ c;
    *res_lo = *res_hi ^ auchCRCLo[index];
    *res_hi = auchCRCHi[index];
}
//------------------------------------------------------------------------------
void get_crc16_ibm(unsigned short * const res)
{}
//==============================================================================
void set_crc16_ccitt(unsigned short * const res)
{
    *res = 0;
}
//------------------------------------------------------------------------------
void update_crc16_ccitt(unsigned short * const res, const unsigned char c)
{
    *res ^= c;
    *res = (*res >> 8) ^ crc16_ccitt_c[*res & 0xFF];
}
//------------------------------------------------------------------------------
void get_crc16_ccitt(unsigned short * const res)
{}
//------------------------------------------------------------------------------
unsigned char lrc_modicon(std::istream &is)
{
    unsigned char res;
    set_lrc_modicon(&res);
    while (true)
    {
        int c = is.peek();
        if (c == EOF) break;
        is.ignore();
        
        update_lrc_modicon(&res, c);
    }
    get_lrc_modicon(&res);
    return res;
}
//------------------------------------------------------------------------------
unsigned char lrc_icp_das(std::istream &is)
{
    unsigned char res;
    set_lrc_icp_das(&res);
    while (true)
    {
        int c = is.peek();
        if (c == EOF) break;
        is.ignore();
        
        update_lrc_icp_das(&res, c);
    }
    get_lrc_icp_das(&res);
    return res;
}
//------------------------------------------------------------------------------
unsigned char lrc_volmag(std::istream &is)
{
    unsigned char res;
    set_lrc_volmag(&res);
    while (true)
    {
        int c = is.peek();
        if (c == EOF) break;
        is.ignore();
        
        update_lrc_volmag(&res, c);
    }
    get_lrc_volmag(&res);
    return res;
}
//------------------------------------------------------------------------------
unsigned short crc16_ibm(std::istream &is)
{
    unsigned short res;
    set_crc16_ibm(&res);
    while (true)
    {
        int c = is.peek();
        if (c == EOF) break;
        is.ignore();
 
        update_crc16_ibm(&res, c);
    }
    get_crc16_ibm(&res);
    return res;
}
//------------------------------------------------------------------------------
unsigned short crc16_ccitt(std::istream &is)
{
    unsigned short res;
    set_crc16_ccitt(&res);
    while (true)
    {
        int c = is.peek();
        if (c == EOF) break;
        is.ignore();
 
        update_crc16_ccitt(&res, c);
    }
    get_crc16_ccitt(&res);
    return res;
}