syncthing/lamport/clock.go
2014-07-13 01:07:49 +02:00

30 lines
563 B
Go

// Copyright (C) 2014 Jakob Borg and Contributors (see the CONTRIBUTORS file).
// All rights reserved. Use of this source code is governed by an MIT-style
// license that can be found in the LICENSE file.
// Package lamport implements a simple Lamport Clock for versioning
package lamport
import "sync"
var Default = Clock{}
type Clock struct {
val uint64
mut sync.Mutex
}
func (c *Clock) Tick(v uint64) uint64 {
c.mut.Lock()
if v > c.val {
c.val = v + 1
c.mut.Unlock()
return v + 1
} else {
c.val++
v = c.val
c.mut.Unlock()
return v
}
}