mirror of
https://github.com/astaxie/beego.git
synced 2024-11-05 12:30:55 +00:00
52 lines
1.1 KiB
Go
52 lines
1.1 KiB
Go
|
// Copyright 2014 The LevelDB-Go Authors. All rights reserved.
|
||
|
|
// Use of this source code is governed by a BSD-style
|
||
|
|
// license that can be found in the LICENSE file.
|
||
|
|
|
||
|
|
// +build darwin dragonfly freebsd linux netbsd openbsd
|
||
|
|
|
||
|
|
package filelock
|
||
|
|
|
||
|
|
import (
|
||
|
|
"io"
|
||
|
|
"os"
|
||
|
|
"syscall"
|
||
|
|
)
|
||
|
|
|
||
|
|
// lockCloser hides all of an os.File's methods, except for Close.
|
||
|
|
type lockCloser struct {
|
||
|
|
f *os.File
|
||
|
|
}
|
||
|
|
|
||
|
|
func (l lockCloser) Close() error {
|
||
|
|
return l.f.Close()
|
||
|
|
}
|
||
|
|
|
||
|
|
func Lock(name string) (io.Closer, error) {
|
||
|
|
f, err := os.Create(name)
|
||
|
|
if err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
Some people tell me FcntlFlock does not exist, so use flock here
|
||
|
|
*/
|
||
|
|
if err := syscall.Flock(int(f.Fd()), syscall.LOCK_EX|syscall.LOCK_NB); err != nil {
|
||
|
|
f.Close()
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
|
||
|
|
// spec := syscall.Flock_t{
|
||
|
|
// Type: syscall.F_WRLCK,
|
||
|
|
// Whence: int16(os.SEEK_SET),
|
||
|
|
// Start: 0,
|
||
|
|
// Len: 0, // 0 means to lock the entire file.
|
||
|
|
// Pid: int32(os.Getpid()),
|
||
|
|
// }
|
||
|
|
// if err := syscall.FcntlFlock(f.Fd(), syscall.F_SETLK, &spec); err != nil {
|
||
|
|
// f.Close()
|
||
|
|
// return nil, err
|
||
|
|
// }
|
||
|
|
|
||
|
|
return lockCloser{f}, nil
|
||
|
|
}
|