Function EncodeUvarintAscending

pkg/util/encoding/encoding.go:325–350

EncodeUvarintAscending encodes the uint64 value using a variable length (length-prefixed) representation. The length is encoded as a single byte indicating the number of encoded bytes (-8) to follow. See EncodeVarintAscending for rationale. The encoded bytes are appended to the supplied buffer and t

(b []byte, v uint64)

// EncodeVarintAscending for rationale. The encoded bytes are appended to the
// supplied buffer and the final buffer is returned.
func EncodeUvarintAscending(b []byte, v uint64) []byte {
	switch {
	case v <= intSmall:
		return append(b, intZero+byte(v))
	case v <= 0xff:
		return append(b, IntMax-7, byte(v))
	case v <= 0xffff:
		return append(b, IntMax-6, byte(v>>8), byte(v))
	case v <= 0xffffff:
		return append(b, IntMax-5, byte(v>>16), byte(v>>8), byte(v))
	case v <= 0xffffffff:
		return append(b, IntMax-4, byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
	case v <= 0xffffffffff:
		return append(b, IntMax-3, byte(v>>32), byte(v>>24), byte(v>>16), byte(v>>8),
			byte(v))
	case v <= 0xffffffffffff:
		return append(b, IntMax-2, byte(v>>40), byte(v>>32), byte(v>>24), byte(v>>16),
			byte(v>>8), byte(v))
	case v <= 0xffffffffffffff:
		return append(b, IntMax-1, byte(v>>48), byte(v>>40), byte(v>>32), byte(v>>24),
			byte(v>>16), byte(v>>8), byte(v))
	default:
		return append(b, IntMax, byte(v>>56), byte(v>>48), byte(v>>40), byte(v>>32),
			byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
	}
}

// EncodeUvarintDescending encodes the uint64 value so that it sorts in
// reverse order, from largest to smallest.