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()
}