35 lines
684 B
Go
35 lines
684 B
Go
//go:build !windows
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package store
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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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func acquireInstanceLock(path string) (func() error, error) {
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if err := ensurePrivateFile(path); err != nil {
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return nil, err
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}
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file, err := os.OpenFile(path, os.O_RDWR, 0)
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if err != nil {
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return nil, err
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}
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if err := syscall.Flock(int(file.Fd()), syscall.LOCK_EX|syscall.LOCK_NB); err != nil {
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_ = file.Close()
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if errors.Is(err, syscall.EWOULDBLOCK) {
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return nil, ErrAlreadyOpen
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}
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return nil, err
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}
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return func() error {
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unlockErr := syscall.Flock(int(file.Fd()), syscall.LOCK_UN)
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closeErr := file.Close()
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if unlockErr != nil {
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return unlockErr
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}
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return closeErr
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}, nil
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}
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