c.mu.Lock()
	defer c.mu.Unlock()
	k := new(byte)
	if c.afterFuncs == nil {
		c.afterFuncs = make(map[*byte]func())
	}
	c.afterFuncs[k] = f
	return func() bool {
		c.mu.Lock()
		defer c.mu.Unlock()
		_, ok := c.afterFuncs[k]
		delete(c.afterFuncs, k)
		return ok
	}
}

func (c *afterFuncContext) cancel(err error) {
	c.mu.Lock()
	defer c.mu.Unlock()
	if c.err != nil {
		return

			if err != nil {
				t.Fatal(err)
			}
			defer teardown()

			p := &plugin{
				endpoint: addr,
			}

			conn, err := p.getOrCreateGRPCConn()
			defer func() {
				err := conn.Close()
				if err != nil {
					t.Error(err)
				}
			}()
			if err != nil {
				t.Fatal(err)
			}

			draPlugins.add("dummy-plugin", p)
			defer draPlugins.delete("dummy-plugin")

	r.discoveryLock.RLock()
	defer r.discoveryLock.RUnlock()

	ret, ok := r.discovery[gv]
	return ret, ok
}

func (r *versionDiscoveryHandler) setDiscovery(gv schema.GroupVersion, discovery *discovery.APIVersionHandler) {
	r.discoveryLock.Lock()
	defer r.discoveryLock.Unlock()

	r.discovery[gv] = discovery
}

func (m *waitingPodsMap) add(wp *waitingPod) {
	m.mu.Lock()
	defer m.mu.Unlock()
	m.pods[wp.GetPod().UID] = wp
}

// remove a WaitingPod from the map.
func (m *waitingPodsMap) remove(uid types.UID) {
	m.mu.Lock()
	defer m.mu.Unlock()
	delete(m.pods, uid)
}

// get a WaitingPod from the map.
func (m *waitingPodsMap) get(uid types.UID) *waitingPod {
	m.mu.RLock()
	defer m.mu.RUnlock()
	return m.pods[uid]
}

	list.Lock()
	defer list.Unlock()

	for id := range targetIDSet {
		target, ok := list.targets[id]
		if ok {
			target.Close()
			delete(list.targets, id)
		}
	}
}

// Targets - list all targets
func (list *TargetList) Targets() []Target {
	if list == nil {
		return []Target{}
	}

	list.RLock()
	defer list.RUnlock()

	}

	cond := sync.NewCond(new(sync.Mutex))

	var wg sync.WaitGroup
	for i := 0; i < 4; i++ {
		wg.Add(1)
		go func() {
			defer wg.Done()

			ctx, cancel := context.WithTimeout(context.Background(), 1*time.Millisecond)
			defer cancel()

			cond.L.Lock()
			defer cond.L.Unlock()

			err := waitOnCond(ctx, cond, func() bool { return false })
			fmt.Println(err)
		}()
	}
	wg.Wait()

		ctx = metadata.NewOutgoingContext(ctx, pr.contextMetadata)
	}
	go func() {
		defer utilruntime.HandleCrash()
		<-stopCh
		pr.mux.Lock()
		defer pr.mux.Unlock()
		pr.stopped = true
		pr.cond.Signal()
	}()
	timer := pr.clock.NewTimer(progressRequestPeriod)
	defer timer.Stop()
	for {
		stopped := func() bool {
			pr.mux.Lock()
			defer pr.mux.Unlock()
			for pr.waiting == 0 && !pr.stopped {
				pr.cond.Wait()
			}

	err := func() error {
		s.lock.Lock()
		defer s.lock.Unlock()
		if s.Errors > 0 {
			s.Errors--
			return fmt.Errorf("injected error")
		}
		return nil
	}()
	if err != nil {
		return err
	}
	return s.Interface.GetList(ctx, key, opts, listObj)
}

func (s *StorageInjectingListErrors) ErrorsConsumed() (bool, error) {
	s.lock.Lock()
	defer s.lock.Unlock()
	return s.Errors == 0, nil
}

}

func Chdir(path string) error {
	// If Chdir is to a relative path, sync working dir first
	if fixwd(path) {
		defer runtime.UnlockOSThread()
	}
	wdmu.Lock()
	defer wdmu.Unlock()

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()
	if err := chdir(path); err != nil {
		return err
	}

	wd, err := getwd()
	if err != nil {
		return err
	}
	wdSet = true
	wdStr = wd
	return nil

	fmc.mirrorPodLock.RLock()
	defer fmc.mirrorPodLock.RUnlock()
	return fmc.mirrorPods.Has(podFullName)
}

func (fmc *FakeMirrorClient) NumOfPods() int {
	fmc.mirrorPodLock.RLock()
	defer fmc.mirrorPodLock.RUnlock()
	return fmc.mirrorPods.Len()
}

func (fmc *FakeMirrorClient) GetPods() []string {
	fmc.mirrorPodLock.RLock()
	defer fmc.mirrorPodLock.RUnlock()
	return sets.List(fmc.mirrorPods)
}