etcd/storage/revision.go
Yicheng Qin ec43e0a4c3 storage: introduce WatchableKV and watch feature
WatchableKV is an interface upon KV, and supports watch feature.
2015-09-14 23:53:03 -07:00

42 lines
871 B
Go

package storage
import "encoding/binary"
type revision struct {
main int64
sub int64
}
func (a revision) GreaterThan(b revision) bool {
if a.main > b.main {
return true
}
if a.main < b.main {
return false
}
return a.sub > b.sub
}
func newRevBytes() []byte {
return make([]byte, 8+1+8)
}
func revToBytes(rev revision, bytes []byte) {
binary.BigEndian.PutUint64(bytes, uint64(rev.main))
bytes[8] = '_'
binary.BigEndian.PutUint64(bytes[9:], uint64(rev.sub))
}
func bytesToRev(bytes []byte) revision {
return revision{
main: int64(binary.BigEndian.Uint64(bytes[0:8])),
sub: int64(binary.BigEndian.Uint64(bytes[9:])),
}
}
type revisions []revision
func (a revisions) Len() int { return len(a) }
func (a revisions) Less(i, j int) bool { return a[j].GreaterThan(a[i]) }
func (a revisions) Swap(i, j int) { a[i], a[j] = a[j], a[i] }