syncthing/internal/lamport/clock.go
Jakob Borg 2c8b627008 Integer type policy
Integers are for numbers, enabling arithmetic like subtractions and for
loops without getting shot in the foot. Unsigneds are for bitfields.

- "int" for numbers that will always be laughably smaller than four
  billion, and where we don't care about the serialization format.

- "int32" for numbers that will always be laughably smaller than four
  billion, and will be serialized to four bytes.

- "int64" for numbers that may approach four billion or will be
  serialized to eight bytes.

- "uint32" and "uint64" for bitfields, depending on required number of
  bits and serialization format. Likewise "uint8" and "uint16", although
  rare in this project since they don't exist in XDR.

- "int8", "int16" and plain "uint" are almost never useful.
2015-01-19 10:34:36 -08:00

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Go

// Copyright (C) 2014 The Syncthing Authors.
//
// This program is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by the Free
// Software Foundation, either version 3 of the License, or (at your option)
// any later version.
//
// This program is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
// more details.
//
// You should have received a copy of the GNU General Public License along
// with this program. If not, see <http://www.gnu.org/licenses/>.
// Package lamport implements a simple Lamport Clock for versioning
package lamport
import "sync"
var Default = Clock{}
type Clock struct {
val int64
mut sync.Mutex
}
func (c *Clock) Tick(v int64) int64 {
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
}
}