/
peers.go
35 lines (31 loc) · 816 Bytes
/
peers.go
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package peers
import (
"encoding/binary"
"fmt"
"net"
"strconv"
)
// Peer encodes connection information for a peer
type Peer struct {
IP net.IP
Port uint16
}
// Unmarshal parses peer IP addresses and ports from a buffer
func Unmarshal(peersBin []byte) ([]Peer, error) {
const peerSize = 6 // 4 for IP, 2 for port
numPeers := len(peersBin) / peerSize
if len(peersBin)%peerSize != 0 {
err := fmt.Errorf("Received malformed peers")
return nil, err
}
peers := make([]Peer, numPeers)
for i := 0; i < numPeers; i++ {
offset := i * peerSize
peers[i].IP = net.IP(peersBin[offset : offset+4])
peers[i].Port = binary.BigEndian.Uint16([]byte(peersBin[offset+4 : offset+6]))
}
return peers, nil
}
func (p Peer) String() string {
return net.JoinHostPort(p.IP.String(), strconv.Itoa(int(p.Port)))
}