8 "github.com/anacrolix/log"
9 "github.com/anacrolix/missinggo/perf"
10 "github.com/anacrolix/missinggo/v2"
11 "github.com/pkg/errors"
14 type Listener interface {
15 // Accept waits for and returns the next connection to the listener.
16 Accept() (net.Conn, error)
18 // Addr returns the listener's network address.
22 type socket interface {
28 func listen(n network, addr string, f firewallCallback, logger log.Logger) (socket, error) {
31 return listenTcp(n.String(), addr)
33 return listenUtp(n.String(), addr, f, logger)
39 func listenTcp(network, address string) (s socket, err error) {
40 l, err := net.Listen(network, address)
43 NetworkDialer: NetworkDialer{
45 Dialer: DefaultNetDialer,
50 type tcpSocket struct {
55 func listenAll(networks []network, getHost func(string) string, port int, f firewallCallback, logger log.Logger) ([]socket, error) {
56 if len(networks) == 0 {
59 var nahs []networkAndHost
60 for _, n := range networks {
61 nahs = append(nahs, networkAndHost{n, getHost(n.String())})
64 ss, retry, err := listenAllRetry(nahs, port, f, logger)
71 type networkAndHost struct {
76 func listenAllRetry(nahs []networkAndHost, port int, f firewallCallback, logger log.Logger) (ss []socket, retry bool, err error) {
77 ss = make([]socket, 1, len(nahs))
78 portStr := strconv.FormatInt(int64(port), 10)
79 ss[0], err = listen(nahs[0].Network, net.JoinHostPort(nahs[0].Host, portStr), f, logger)
81 return nil, false, errors.Wrap(err, "first listen")
84 if err != nil || retry {
85 for _, s := range ss {
91 portStr = strconv.FormatInt(int64(missinggo.AddrPort(ss[0].Addr())), 10)
92 for _, nah := range nahs[1:] {
93 s, err := listen(nah.Network, net.JoinHostPort(nah.Host, portStr), f, logger)
96 missinggo.IsAddrInUse(err) && port == 0,
97 errors.Wrap(err, "subsequent listen")
104 // This isn't aliased from go-libutp since that assumes CGO.
105 type firewallCallback func(net.Addr) bool
107 func listenUtp(network, addr string, fc firewallCallback, logger log.Logger) (socket, error) {
108 us, err := NewUtpSocket(network, addr, fc, logger)
109 return utpSocketSocket{us, network}, err
112 // utpSocket wrapper, additionally wrapped for the torrent package's socket interface.
113 type utpSocketSocket struct {
118 func (me utpSocketSocket) DialerNetwork() string {
122 func (me utpSocketSocket) Dial(ctx context.Context, addr string) (conn net.Conn, err error) {
123 defer perf.ScopeTimerErr(&err)()
124 return me.utpSocket.DialContext(ctx, me.network, addr)