43 lines
692 B
Go
43 lines
692 B
Go
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package database
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import (
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"os"
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"golang.org/x/sys/unix"
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)
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type LockChecker interface {
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Locked() (bool, error)
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}
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type VFSLockChecker struct {
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path string
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}
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func (checker *VFSLockChecker) Locked() (bool, error) {
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f, err := os.Open(checker.path)
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if err != nil {
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return false, err
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}
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// Get the the lock mode
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var lock unix.Flock_t
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// See man (fcntl)
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unix.FcntlFlock(f.Fd(), unix.F_GETLK, &lock)
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// Check if lock is F_RDLCK (non-exclusive) or F_WRLCK (exclusive)
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if lock.Type == unix.F_RDLCK {
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//fmt.Println("Lock is F_RDLCK")
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return false, nil
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}
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if lock.Type == unix.F_WRLCK {
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//fmt.Println("Lock is F_WRLCK (locked !)")
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return true, nil
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}
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return false, nil
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}
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