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