示例#1
0
文件: walk.go 项目: arv/noms-old
func doTreeWalkP(v types.Value, vr types.ValueReader, cb SomeCallback, concurrency int) {
	rq := newRefQueue()
	f := newFailure()

	visited := map[ref.Ref]bool{}
	mu := sync.Mutex{}
	wg := sync.WaitGroup{}

	var processVal func(v types.Value)
	processVal = func(v types.Value) {
		if cb(v) {
			return
		}

		if r, ok := v.(types.RefBase); ok {
			wg.Add(1)
			rq.tail() <- r.TargetRef()
		} else {
			for _, c := range v.ChildValues() {
				processVal(c)
			}
		}
	}

	processRef := func(r ref.Ref) {
		defer wg.Done()

		mu.Lock()
		skip := visited[r]
		visited[r] = true
		mu.Unlock()

		if skip || f.didFail() {
			return
		}

		v := vr.ReadValue(r)
		if v == nil {
			f.fail(fmt.Errorf("Attempt to copy absent ref:%s", r.String()))
			return
		}
		processVal(v)
	}

	iter := func() {
		for r := range rq.head() {
			processRef(r)
		}
	}

	for i := 0; i < concurrency; i++ {
		go iter()
	}

	processVal(v)
	wg.Wait()

	rq.close()

	f.checkNotFailed()
}