CRC.h

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/*
 **    CRC Calculator by Paul Johnston
 **    Version 1.0 Copyright 10/9/96 (September)
 **    Explicitly released to the public domain 30-Oct-1996 by the author
 */
 
/* Custom Hungarian types:
 **
 ** crp  - CRC Polynomial
 ** crgi - CRC reGister Inital value
 ** crxo - CRC Xor Out value
 ** crpt - CRC Precalculated Table
 ** crr  - is CRC Reversed
 ** crst - CRC Standard Type
 */
 
#ifndef PAJ_CRC
#define PAJ_CRC
 
#ifdef _MSC_VER
typedef unsigned int uint32_t;
#else
#include <stdint.h>
#endif
 
class PData
{
public:
    uint32_t l;
    void *pData;
};
 
uint32_t Reflect(uint32_t toref, char w);
 
enum Crst
{
    Crc16 = 0,
    Crc32,
    JamCrc,
    XModemCrc,
    ZModemCrc16,
    ZModemCrc32
};
 
class CheckCalc
{
public:
    virtual uint32_t Add(uint32_t crc, char *sCrc)=0;
    virtual uint32_t Add(uint32_t crc, unsigned char sCrc)=0;
    virtual uint32_t Add(uint32_t crc, PData sCrc)=0;
    virtual uint32_t Init()=0;
};
 
class CrcCalc: CheckCalc
{
private:
    uint32_t acrpt[256], crp, crgi, crxo;
    unsigned char fcrr, crwd;
    void InitCalc(uint32_t crpNew, uint32_t crgiNew,
        uint32_t crxoNew, unsigned char fcrrNew,
        unsigned char crwdNew);
 
public:
    uint32_t Add(uint32_t crc, char *sCrc);
    uint32_t Add(uint32_t crc, unsigned char sCrc);
    uint32_t Add(uint32_t crc, PData sCrc);
    uint32_t Init();
    CrcCalc(uint32_t crpNew, uint32_t crgiNew = 0,
        uint32_t crxoNew = 0, unsigned char fcrrNew = 1,
        unsigned char crwdNew = 32);
    CrcCalc(Crst crst);
};
 
class Crc
{
private:
    uint32_t crc;
    CheckCalc *crccalc;
 
public:
    uint32_t crcGet()
    {
        return crc;
    }
    ;
    void Add(char *sCrc)
    {
        crc = crccalc->Add(crc, sCrc);
    }
    void Add(char sCrc)
    {
        crc = crccalc->Add(crc, sCrc);
    }
    void Add(PData sCrc)
    {
        crc = crccalc->Add(crc, sCrc);
    }
    void NewCrc()
    {
        crc = crccalc->Init();
    }
 
    operator uint32_t()
    {
        return crcGet();
    }
    void operator <<(char *sCrc)
    {
        Add(sCrc);
    }
    void operator <<(char sCrc)
    {
        Add(sCrc);
    }
    void operator <<(PData sCrc)
    {
        Add(sCrc);
    }
    void operator =(int iNew)
    {
        if (iNew == 0)
            NewCrc();
    }
 
    Crc(CheckCalc *crccalcNew)
    {
        crccalc = crccalcNew;
        NewCrc();
    }
};
 
#endif // PAJ_CRC