Convert C to PHP for CRC16 Function

问题:

I need help in converting C code into PHP. The following is the C Code:

static const U16 crctab16[] = { 0x0000, 0x1189, ... };  U16 GetCrc16(const U8* pData, int nLength) {   U16 fcs = 0xffff;   while(nLength > 0)   {     fcs = (fcs >> 8) ^ crctab16[fcs ^ *pData) & 0xff];     nLength--; pData++;   }   return ~fcs; }

I have the fo