containerd/content/locks.go
Derek McGowan 1cdb010783
Replace lockfile with reference lock
Updates content service to handle lock errors and return
them to the client. The client remote handler has been
updated to retry when a resource is locked until the
resource is unlocked or the expected resource exists.

Signed-off-by: Derek McGowan <derek@mcgstyle.net>
2017-06-08 16:07:38 -07:00

38 lines
555 B
Go

package content
import (
"sync"
"github.com/pkg/errors"
)
// Handles locking references
// TODO: use boltdb for lock status
var (
// locks lets us lock in process
locks = map[string]struct{}{}
locksMu sync.Mutex
)
func tryLock(ref string) error {
locksMu.Lock()
defer locksMu.Unlock()
if _, ok := locks[ref]; ok {
return errors.Wrapf(ErrLocked, "key %s is locked", ref)
}
locks[ref] = struct{}{}
return nil
}
func unlock(ref string) {
locksMu.Lock()
defer locksMu.Unlock()
if _, ok := locks[ref]; ok {
delete(locks, ref)
}
}