/// <summary>
 /// Calculates an on-going hash using the input byte array.
 /// </summary>
 /// <param name="input">The input array used for calculating the hash.</param>
 /// <param name="offset">The offset in the input buffer to calculate from.</param>
 /// <param name="count">The number of bytes to use from input.</param>
 internal void UpdateHash(byte[] input, int offset, int count)
 {
     if (offset != 0)
     {
         throw new NotImplementedException("non-zero offset for Crc64Wrapper update not supported");
     }
     if (count > 0)
     {
         this.uCRC = Crc64.ComputeSlicedSafe(input, count, this.uCRC);
     }
 }