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34 lines
1.0 KiB
Go
34 lines
1.0 KiB
Go
// Package flock provides portable file locking. It is essentially ripped out
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// from the code of github.com/syndtr/goleveldb. Strange enough that the
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// standard library does not provide this functionality. Once this package has
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// proven to work as expected, we should probably turn it into a separate
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// general purpose package for humanity.
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package flock
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import (
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"os"
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"path/filepath"
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)
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// Releaser provides the Release method to release a file lock.
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type Releaser interface {
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Release() error
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}
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// New locks the file with the provided name. If the file does not exist, it is
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// created. The returned Releaser is used to release the lock. existed is true
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// if the file to lock already existed. A non-nil error is returned if the
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// locking has failed. Neither this function nor the returned Releaser is
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// goroutine-safe.
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func New(fileName string) (r Releaser, existed bool, err error) {
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if err = os.MkdirAll(filepath.Dir(fileName), 0755); err != nil {
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return
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}
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_, err = os.Stat(fileName)
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existed = err == nil
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r, err = newLock(fileName)
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return
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}
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