Files
EdgeNode/internal/utils/fs/locker.go
GoEdgeLab c19be78e0d v1.4.1
2024-07-27 15:42:50 +08:00

83 lines
1.3 KiB
Go

// Copyright 2023 GoEdge goedge.cdn@gmail.com. All rights reserved. Official site: https://goedge.cloud .
package fsutils
import (
"os"
"syscall"
"time"
)
type Locker struct {
path string
fp *os.File
}
func NewLocker(path string) *Locker {
return &Locker{
path: path + ".lock",
}
}
func (this *Locker) TryLock() (ok bool, err error) {
if this.fp == nil {
fp, err := os.OpenFile(this.path, os.O_CREATE|os.O_WRONLY, 0666)
if err != nil {
return false, err
}
this.fp = fp
}
return this.tryLock()
}
func (this *Locker) Lock() error {
if this.fp == nil {
fp, err := os.OpenFile(this.path, os.O_CREATE|os.O_WRONLY, 0666)
if err != nil {
return err
}
this.fp = fp
}
for {
b, err := this.tryLock()
if err != nil {
_ = this.fp.Close()
return err
}
if b {
return nil
}
time.Sleep(100 * time.Millisecond)
}
}
func (this *Locker) Release() error {
err := this.fp.Close()
if err != nil {
return err
}
this.fp = nil
return nil
}
func (this *Locker) tryLock() (ok bool, err error) {
err = syscall.Flock(int(this.fp.Fd()), syscall.LOCK_EX|syscall.LOCK_NB)
if err == nil {
return true, nil
}
errno, isErrNo := err.(syscall.Errno)
if !isErrNo {
return
}
if !errno.Temporary() {
return
}
err = nil // 不提示错误
return
}