50 lines
748 B
Go
50 lines
748 B
Go
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package lockfile
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import (
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"errors"
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"os"
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"syscall"
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)
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type Lockfile struct {
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path string
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fd int
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}
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func New(path string) *Lockfile {
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return &Lockfile{path: path}
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}
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func (lf *Lockfile) Lock() error {
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fd, err := syscall.Open(lf.path, syscall.O_CREAT | syscall.O_RDWR, 0600)
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if err != nil {
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return err
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}
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lf.fd = fd
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err = syscall.Flock(lf.fd, syscall.LOCK_EX | syscall.LOCK_NB)
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if err != nil {
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return err
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}
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return nil
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}
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func (lf *Lockfile) Unlock() error {
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if lf.fd == 0 {
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panic(errors.New("Lockfile was not locked"))
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}
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err := syscall.Flock(lf.fd, syscall.LOCK_UN)
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if err != nil {
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return err
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}
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err = syscall.Close(lf.fd)
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if err != nil {
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return err
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}
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os.Remove(lf.path)
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if err != nil {
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return err
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}
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return nil
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}
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