case <-ctx.Done():
			return false
		default:
			// Try to acquire the lock.
			if locked = lock(ctx, dm.clnt, &locks, id, source, isReadLock, tolerance, quorum, dm.Names...); locked {
				dm.m.Lock()

				// If success, copy array to object
				if isReadLock {
					copy(dm.readLocks, locks)
				} else {
					copy(dm.writeLocks, locks)
				}

				dm.m.Unlock()

	Source          string // Contains line, function and filename requesting the lock.
	Group           bool   // indicates if it was a group lock.
	Owner           string // Owner represents the UUID of the owner who originally requested the lock.
	Quorum          int    // Quorum represents the quorum required for this lock to be active.
	idx             int    `msg:"-"` // index of the lock in the lockMap.
}

type NetLocker interface {
	// Do read lock for given LockArgs.  It should return
	// * a boolean to indicate success/failure of the operation
	// * an error on failure of lock request operation.
	RLock(ctx context.Context, args LockArgs) (bool, error)

	// Do write lock for given LockArgs. It should return
	// * a boolean to indicate success/failure of the operation
	// * an error on failure of lock request operation.

     * always under a lock.
     */
    private static final class SupplantableFuture implements Cancellable {
      private final ReentrantLock lock;

      @GuardedBy("lock")
      private Future<@Nullable Void> currentFuture;

      SupplantableFuture(ReentrantLock lock, Future<@Nullable Void> currentFuture) {
        this.lock = lock;
        this.currentFuture = currentFuture;
      }

    }

    static TestCondition create() {
      Lock lock = new ReentrantLock();
      Condition condition = lock.newCondition();
      return new TestCondition(lock, condition);
    }

    @Override
    public void await() throws InterruptedException {
      lock.lock();
      try {
        condition.await();
      } finally {
        lock.unlock();
      }
    }

    @Override

	}

	l.mutex.Lock()
	defer l.mutex.Unlock()
	var locksHeld int64
	if locksHeld, reply = l.lockMap[args.Resources[0]]; !reply { // No lock is held on the given name
		return false, fmt.Errorf("RUnlock attempted on an unlocked entity: %s", args.Resources[0])
	}
	if reply = locksHeld != WriteLock; !reply { // A write-lock is held, cannot release a read lock

			Op:   "open",
			Path: path,
			Err:  syscall.EINVAL,
		}
	}

	lock := syscall.Flock_t{
		Start:  0,
		Len:    0,
		Pid:    0,
		Type:   lockType,
		Whence: 0,
	}

	f, err := os.OpenFile(path, flag, perm)
	if err != nil {
		return nil, err
	}

	if err = syscall.FcntlFlock(f.Fd(), rlockType, &lock); err != nil {
		f.Close()
		if err == syscall.EAGAIN {
			err = ErrAlreadyLocked
		}

}

// RLock holds a read lock on lm.
//
// If one or more read lock are already in use, it will grant another lock.
// Otherwise the calling go routine blocks until the mutex is available.
func (lm *LRWMutex) RLock() {
	const isWriteLock = false
	lm.lockLoop(context.Background(), lm.id, lm.source, 1<<63-1, isWriteLock)
}

// GetRLock tries to get a read lock on lm before the timeout occurs.

### Locks

We have 3 different things that we synchronize on.

#### Http2Connection

This lock guards internal state of each connection. This lock is never held for blocking operations. That means that we acquire the lock, read or write a few fields and release the lock. No I/O and no application-layer callbacks.

#### Http2Stream

	rng := rand.New(rand.NewSource(0))
	quorum := 0
	// Numbers of unique locks
	for _, locks := range []int{100, 1000, 1e6} {
		if testing.Short() && locks > 100 {
			continue
		}
		t.Run(fmt.Sprintf("%d-locks", locks), func(t *testing.T) {
			// Number of readers per lock...
			for _, readers := range []int{1, 10, 100} {
				if locks > 1000 && readers > 1 {
					continue
				}