#ifndef __CRC_H__
#define __CRC_H__

#ifdef  __CRC_C__

#define _EXTERN

#else

extern const unsigned short Crc16Table[256];
extern const unsigned short CrcCcittTable[256];
extern const unsigned long  Crc32Table[256];

#define _EXTERN extern "C"

#endif

#define UPDC16(cp,crc)      (Crc16Table[((crc^cp) & 0xff)] ^ (crc >> 8))
#define UPDCCCITT(cp,crc)   (CrcCcittTable[((crc >> 8) & 0xff)] ^ (crc << 8) ^ cp)
#define UPDC32(octet,crc)   (Crc32Table[((crc) ^ (octet)) & 0xff] ^ ((crc) >> 8))

_EXTERN unsigned short Crc16(unsigned char *Data, unsigned long Len);
_EXTERN unsigned short CrcCcitt(unsigned char *Data, unsigned long Len);
_EXTERN unsigned long  Crc32(unsigned char *Data, unsigned long Len);

#undef  _EXTERN

#endif