package inetcksum

import (
	`encoding/binary`
)

const (
	// EmptyCksum is returned for checksums of 0-length byte slices/buffers.
	EmptyCksum uint16 = 0xffff
)

const (
	/*
		cksumMask is AND'd with a checksum to get the "carried ones"
		(the lower 16 bits before folding carries).
	*/
	cksumMask uint32 = 0x0000ffff
	/*
		cksumShift is used in the "carried-ones folding";
		it's the number of bits to right-shift the carry-over.
	*/
	cksumShift uint32 = 0x00000010
	/*
		padShift is used to "pad out" a checksum for odd-length buffers by left-shifting.
		It positions the high-byte of a 16-byte "word" (big-endian, as per ord below).
	*/
	padShift uint32 = 0x00000008
)

var (
	// ord is the byte order used by the Internet Checksum.
	ord binary.ByteOrder = binary.BigEndian
)