mirror of
https://github.com/prometheus/prometheus.git
synced 2024-11-09 23:24:05 -08:00
42 lines
1.3 KiB
Go
42 lines
1.3 KiB
Go
// Copyright 2016 The Prometheus Authors
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package fileutil
|
|
|
|
import (
|
|
"os"
|
|
"path/filepath"
|
|
)
|
|
|
|
// Releaser provides the Release method to release a file lock.
|
|
type Releaser interface {
|
|
Release() error
|
|
}
|
|
|
|
// Flock locks the file with the provided name. If the file does not exist, it is
|
|
// created. The returned Releaser is used to release the lock. existed is true
|
|
// if the file to lock already existed. A non-nil error is returned if the
|
|
// locking has failed. Neither this function nor the returned Releaser is
|
|
// goroutine-safe.
|
|
func Flock(fileName string) (r Releaser, existed bool, err error) {
|
|
if err = os.MkdirAll(filepath.Dir(fileName), 0o755); err != nil {
|
|
return nil, false, err
|
|
}
|
|
|
|
_, err = os.Stat(fileName)
|
|
existed = err == nil
|
|
|
|
r, err = newLock(fileName)
|
|
return r, existed, err
|
|
}
|