31 lines
828 B
Go
31 lines
828 B
Go
//go:build linux || darwin
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package retention
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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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// lockJob 的非阻塞文件锁随进程退出自动释放，不使用永不过期的“锁目录”。
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func lockJob(root *os.Root) (*os.File, error) {
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f, err := root.OpenFile(".lock", os.O_CREATE|os.O_RDWR|syscall.O_NOFOLLOW, 0600)
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if err != nil {
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return nil, err
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}
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info, err := f.Stat()
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if err != nil || !info.Mode().IsRegular() || info.Mode().Perm()&0077 != 0 {
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f.Close()
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return nil, errors.New("invalid archive lock file")
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}
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if err := syscall.Flock(int(f.Fd()), syscall.LOCK_EX|syscall.LOCK_NB); err != nil {
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f.Close()
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if errors.Is(err, syscall.EWOULDBLOCK) || errors.Is(err, syscall.EAGAIN) {
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return nil, ErrArchiveBusy
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}
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return nil, errors.New("archive filesystem does not support locking")
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}
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return f, nil
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}
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