Golang go-cid.Cid類代碼示例

func (bs *blockstore) Get(k *cid.Cid) (blocks.Block, error) {
	if k == nil {
		log.Error("nil cid in blockstore")
		return nil, ErrNotFound
	}

	maybeData, err := bs.datastore.Get(dshelp.CidToDsKey(k))
	if err == ds.ErrNotFound {
		return nil, ErrNotFound
	}
	if err != nil {
		return nil, err
	}
	bdata, ok := maybeData.([]byte)
	if !ok {
		return nil, ValueTypeMismatch
	}

	if bs.rehash {
		rbcid, err := k.Prefix().Sum(bdata)
		if err != nil {
			return nil, err
		}

		if !rbcid.Equals(k) {
			return nil, ErrHashMismatch
		}

		return blocks.NewBlockWithCid(bdata, rbcid)
	} else {
		return blocks.NewBlockWithCid(bdata, k)
	}
}

func (rs *s) Providers(c *cid.Cid) []pstore.PeerInfo {
	rs.delayConf.Query.Wait() // before locking

	rs.lock.RLock()
	defer rs.lock.RUnlock()
	k := c.KeyString()

	var ret []pstore.PeerInfo
	records, ok := rs.providers[k]
	if !ok {
		return ret
	}
	for _, r := range records {
		if time.Now().Sub(r.Created) > rs.delayConf.ValueVisibility.Get() {
			ret = append(ret, r.Peer)
		}
	}

	for i := range ret {
		j := rand.Intn(i + 1)
		ret[i], ret[j] = ret[j], ret[i]
	}

	return ret
}

func wantlistContains(wantlist *pb.Message_Wantlist, c *cid.Cid) bool {
	for _, e := range wantlist.GetEntries() {
		if e.GetBlock() == c.KeyString() {
			return true
		}
	}
	return false
}

func hash(seed uint32, c *cid.Cid) uint32 {
	var buf [4]byte
	binary.LittleEndian.PutUint32(buf[:], seed)
	h := fnv.New32a()
	_, _ = h.Write(buf[:])
	_, _ = h.Write(c.Bytes())
	return h.Sum32()
}

// FindLinks searches this nodes links for the given key,
// returns the indexes of any links pointing to it
func FindLinks(links []*cid.Cid, c *cid.Cid, start int) []int {
	var out []int
	for i, lnk_c := range links[start:] {
		if c.Equals(lnk_c) {
			out = append(out, i+start)
		}
	}
	return out
}

func (n *dagService) GetLinks(ctx context.Context, c *cid.Cid) ([]*node.Link, error) {
	if c.Type() == cid.Raw {
		return nil, nil
	}
	node, err := n.Get(ctx, c)
	if err != nil {
		return nil, err
	}
	return node.Links(), nil
}

// NewBlockWithHash creates a new block when the hash of the data
// is already known, this is used to save time in situations where
// we are able to be confident that the data is correct
func NewBlockWithCid(data []byte, c *cid.Cid) (*BasicBlock, error) {
	if u.Debug {
		chkc, err := c.Prefix().Sum(data)
		if err != nil {
			return nil, err
		}

		if !chkc.Equals(c) {
			return nil, ErrWrongHash
		}
	}
	return &BasicBlock{data: data, cid: c}, nil
}

// if ok == false has is inconclusive
// if ok == true then has respons to question: is it contained
func (b *arccache) hasCached(k *cid.Cid) (has bool, ok bool) {
	b.total.Inc()
	if k == nil {
		log.Error("nil cid in arccache")
		// Return cache invalid so the call to blockstore happens
		// in case of invalid key and correct error is created.
		return false, false
	}

	h, ok := b.arc.Get(k.KeyString())
	if ok {
		b.hits.Inc()
		return h.(bool), true
	}
	return false, false
}

func (rs *s) Announce(p pstore.PeerInfo, c *cid.Cid) error {
	rs.lock.Lock()
	defer rs.lock.Unlock()

	k := c.KeyString()

	_, ok := rs.providers[k]
	if !ok {
		rs.providers[k] = make(map[peer.ID]providerRecord)
	}
	rs.providers[k][p.ID] = providerRecord{
		Created: time.Now(),
		Peer:    p,
	}
	return nil
}

func (m *impl) addEntry(c *cid.Cid, priority int, cancel bool) {
	k := c.KeyString()
	e, exists := m.wantlist[k]
	if exists {
		e.Priority = priority
		e.Cancel = cancel
	} else {
		m.wantlist[k] = Entry{
			Entry: &wantlist.Entry{
				Cid:      c,
				Priority: priority,
			},
			Cancel: cancel,
		}
	}
}

// Write one edge
func (rw *RefWriter) WriteEdge(from, to *cid.Cid, linkname string) error {
	if rw.Ctx != nil {
		select {
		case <-rw.Ctx.Done(): // just in case.
			return rw.Ctx.Err()
		default:
		}
	}

	var s string
	switch {
	case rw.PrintFmt != "":
		s = rw.PrintFmt
		s = strings.Replace(s, "<src>", from.String(), -1)
		s = strings.Replace(s, "<dst>", to.String(), -1)
		s = strings.Replace(s, "<linkname>", linkname, -1)
	default:
		s += to.String()
	}

	rw.out <- &RefWrapper{Ref: s}
	return nil
}

func (b *arccache) addCache(c *cid.Cid, has bool) {
	b.arc.Add(c.KeyString(), has)
}

func CidToDsKey(k *cid.Cid) ds.Key {
	return NewKeyFromBinary(k.KeyString())
}

// taskKey returns a key that uniquely identifies a task.
func taskKey(p peer.ID, k *cid.Cid) string {
	return string(p) + k.KeyString()
}

func CidToDsKey(k *cid.Cid) ds.Key {
	return NewKeyFromBinary(k.Bytes())
}