var key string
	var hasKey bool
	for {
		tok, err := d.Token()
		if err == io.EOF {
			break
		}
		if err != nil {
			return nil, err
		}
		if tok, ok := tok.(xml.StartElement); ok {
			if tok.Name.Local == "key" {
				if err := d.DecodeElement(&key, &tok); err != nil {
					return nil, err
				}
				hasKey = true
			} else if hasKey {
				var val string
				var err error

	doneCh := make(chan struct{})
	defer close(doneCh)
	if err := ps.Subscribe(MaskAll, ch1, doneCh, nil); err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if err := ps.Subscribe(MaskAll, ch2, doneCh, nil); err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	ps.Lock()
	defer ps.Unlock()

	if len(ps.subs) != 2 || ps.NumSubscribers(MaskAll) != 2 || ps.Subscribers() != 2 {
		t.Fatalf("expected 2 subscribers")
	}
}

package pubsub

import (
	"math"
	"math/bits"
)

// Mask allows filtering by a bitset mask.
type Mask uint64

const (
	// MaskAll is the mask for all entries.
	MaskAll Mask = math.MaxUint64
)

// MaskFromMaskable extracts mask from an interface.
func MaskFromMaskable(m Maskable) Mask {
	return Mask(m.Mask())
}

// Contains returns whether *all* flags in other is present in t.
func (t Mask) Contains(other Mask) bool {

// If data is not xlv2, it is returned in full.
func readXLMetaNoData(r io.Reader, size int64) ([]byte, error) {
	initial := size
	hasFull := true
	if initial > metaDataReadDefault {
		initial = metaDataReadDefault
		hasFull = false
	}

	buf := metaDataPoolGet()[:initial]
	_, err := io.ReadFull(r, buf)
	if err != nil {
		return nil, fmt.Errorf("readXLMetaNoData(io.ReadFull): %w", err)

	ret := &ObjectSet{}
	for _, obj := range o.objMap {
		hasAll := true
		for _, l := range labels {
			lkv := strings.Split(l, "=")
			if len(lkv) != 2 {
				panic("label must have format key=value")
			}
			if !hasLabel(obj, lkv[0], lkv[1]) {
				hasAll = false
				break
			}
		}
		if hasAll {
			ret.append(obj)
		}
	}
	return ret
}