moby/libnetwork/ipbits/uint128.go
Cory Snider 3c59ef247f libnet/ipam: use netip types internally
The netip types can be used as map keys, unlike net.IP and friends,
which is a very useful property to have for this application.

Signed-off-by: Cory Snider <csnider@mirantis.com>
2023-02-23 18:10:01 -05:00

62 lines
1.1 KiB
Go

package ipbits
import (
"encoding/binary"
"math/bits"
)
type uint128 struct{ hi, lo uint64 }
func uint128From16(b [16]byte) uint128 {
return uint128{
hi: binary.BigEndian.Uint64(b[:8]),
lo: binary.BigEndian.Uint64(b[8:]),
}
}
func uint128From(x uint64) uint128 {
return uint128{lo: x}
}
func (x uint128) add(y uint128) uint128 {
lo, carry := bits.Add64(x.lo, y.lo, 0)
hi, _ := bits.Add64(x.hi, y.hi, carry)
return uint128{hi: hi, lo: lo}
}
func (x uint128) lsh(n uint) uint128 {
if n > 64 {
return uint128{hi: x.lo << (n - 64)}
}
return uint128{
hi: x.hi<<n | x.lo>>(64-n),
lo: x.lo << n,
}
}
func (x uint128) rsh(n uint) uint128 {
if n > 64 {
return uint128{lo: x.hi >> (n - 64)}
}
return uint128{
hi: x.hi >> n,
lo: x.lo>>n | x.hi<<(64-n),
}
}
func (x uint128) and(y uint128) uint128 {
return uint128{hi: x.hi & y.hi, lo: x.lo & y.lo}
}
func (x uint128) not() uint128 {
return uint128{hi: ^x.hi, lo: ^x.lo}
}
func (x uint128) fill16(a *[16]byte) {
binary.BigEndian.PutUint64(a[:8], x.hi)
binary.BigEndian.PutUint64(a[8:], x.lo)
}
func (x uint128) uint64() uint64 {
return x.lo
}