status-go/vendor/github.com/libp2p/go-libp2p-circuit/util.go

119 lines
2.6 KiB
Go

package relay
import (
"errors"
"io"
pb "github.com/libp2p/go-libp2p-circuit/pb"
"github.com/libp2p/go-libp2p-core/peer"
pool "github.com/libp2p/go-buffer-pool"
"github.com/libp2p/go-msgio/protoio"
"github.com/gogo/protobuf/proto"
ma "github.com/multiformats/go-multiaddr"
"github.com/multiformats/go-varint"
)
func peerToPeerInfo(p *pb.CircuitRelay_Peer) (peer.AddrInfo, error) {
if p == nil {
return peer.AddrInfo{}, errors.New("nil peer")
}
id, err := peer.IDFromBytes(p.Id)
if err != nil {
return peer.AddrInfo{}, err
}
addrs := make([]ma.Multiaddr, 0, len(p.Addrs))
for _, addrBytes := range p.Addrs {
a, err := ma.NewMultiaddrBytes(addrBytes)
if err == nil {
addrs = append(addrs, a)
}
}
return peer.AddrInfo{ID: id, Addrs: addrs}, nil
}
func peerInfoToPeer(pi peer.AddrInfo) *pb.CircuitRelay_Peer {
addrs := make([][]byte, len(pi.Addrs))
for i, addr := range pi.Addrs {
addrs[i] = addr.Bytes()
}
p := new(pb.CircuitRelay_Peer)
p.Id = []byte(pi.ID)
p.Addrs = addrs
return p
}
func incrementTag(v int) int {
return v + 1
}
func decrementTag(v int) int {
if v > 0 {
return v - 1
} else {
return v
}
}
type delimitedReader struct {
r io.Reader
buf []byte
}
// The gogo protobuf NewDelimitedReader is buffered, which may eat up stream data.
// So we need to implement a compatible delimited reader that reads unbuffered.
// There is a slowdown from unbuffered reading: when reading the message
// it can take multiple single byte Reads to read the length and another Read
// to read the message payload.
// However, this is not critical performance degradation as
// - the reader is utilized to read one (dialer, stop) or two messages (hop) during
// the handshake, so it's a drop in the water for the connection lifetime.
// - messages are small (max 4k) and the length fits in a couple of bytes,
// so overall we have at most three reads per message.
func newDelimitedReader(r io.Reader, maxSize int) *delimitedReader {
return &delimitedReader{r: r, buf: pool.Get(maxSize)}
}
func (d *delimitedReader) Close() {
if d.buf != nil {
pool.Put(d.buf)
d.buf = nil
}
}
func (d *delimitedReader) ReadByte() (byte, error) {
buf := d.buf[:1]
_, err := d.r.Read(buf)
return buf[0], err
}
func (d *delimitedReader) ReadMsg(msg proto.Message) error {
mlen, err := varint.ReadUvarint(d)
if err != nil {
return err
}
if uint64(len(d.buf)) < mlen {
return errors.New("Message too large")
}
buf := d.buf[:mlen]
_, err = io.ReadFull(d.r, buf)
if err != nil {
return err
}
return proto.Unmarshal(buf, msg)
}
func newDelimitedWriter(w io.Writer) protoio.WriteCloser {
return protoio.NewDelimitedWriter(w)
}