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baca6faa1c
This mimics the locking leveldb is performing anyway. Advantages of doing it separately: - Should we ever replace the leveldb implementation by one without double-start protection, we are still good. - In contrast to leveldb, the new code creates a meaningful error message.
47 lines
718 B
Go
47 lines
718 B
Go
// +build solaris
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package flock
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import (
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"os"
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"syscall"
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)
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type unixLock struct {
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f *os.File
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}
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func (l *unixLock) Release() error {
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if err := l.set(false); err != nil {
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return err
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}
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return l.f.Close()
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}
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func (l *unixLock) set(lock bool) error {
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flock := syscall.Flock_t{
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Type: syscall.F_UNLCK,
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Start: 0,
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Len: 0,
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Whence: 1,
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}
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if lock {
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flock.Type = syscall.F_WRLCK
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}
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return syscall.FcntlFlock(l.f.Fd(), syscall.F_SETLK, &flock)
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}
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func newLock(fileName string) (Releaser, error) {
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f, err := os.OpenFile(fileName, os.O_RDWR|os.O_CREATE, 0644)
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if err != nil {
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return nil, err
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}
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l := &unixLock{f}
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err = l.set(true)
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if err != nil {
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f.Close()
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return nil, err
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}
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return l, nil
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}
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