locker

type Service interface {
	// PreLock must be called prior to locking one or more public keys.
	// It obtains a locker-wide mutex, to ensure that only one goroutine
	// can be locking or unlocking groups of public keys at a time.
	PreLock()
	// PostLock must be called after locking one or more public keys.
	// It frees the locker-wide mutex obtained by PreLock().
	PostLock()
	// Lock acquires a lock for a given public key.
	// If more than one lock is being acquired in a batch, ensure that
	// PreLock() is called beforehand and PostLock() afterwards.
	Lock(key [48]byte)
	// Unlock frees a lock for a given public key.
	Unlock(key [48]byte)
}