// The first thing to do after a connection is established is to exchange version.
// For kaiju it goes as follows:
// 1. Send out my version message, if outgoing == true
// 2. Expect the remote peer send it's version message
// 3. Once the message from remote peer is received, send verack
// 4. Send out my version message, if outgoing == false
// 5. Done, knet.Peer starts to work
func (p *Peer) versionHankshake() error {
// Step 1
if p.outgoing {
err := p.sendVersionMsg()
if err != nil {
return err
}
}
// Step 2
msg, err := btcmsg.ReadMsg(p.conn)
if err != nil {
return err
} else {
if ver, ok := msg.(*btcmsg.Message_version); ok {
// TODO: more check
p.info = ver.Addr_from
} else {
return errors.New("Wrong message type when doing versionHankshake")
}
}
// Step 3
vamsg := btcmsg.NewVerAckMsg()
err = btcmsg.WriteMsg(p.conn, vamsg)
if err != nil {
return err
}
// Step 4
if !p.outgoing {
err := p.sendVersionMsg()
if err != nil {
return err
}
}
return nil
}
func (p *Peer) loopMain() {
// This "running" is used to fix a bug about "break",
// so if you break in "select", you cannot get out of "for".
running := true
for running {
select {
case m := <-p.sendChan:
ch := make(chan error, 1)
go func() { ch <- btcmsg.WriteMsg(p.conn, m.msg) }()
select {
case err := <-ch:
if m.errChan != nil {
m.errChan <- err
}
if err != nil {
running = false
}
case <-time.After(m.timeout):
if m.errChan != nil {
m.errChan <- errors.New("Peer send message timeout.")
}
if m.timeout >= defaultSendMsgTimeout {
running = false
}
case <-p.done:
running = false
}
case <-p.keepAliveTimer.C:
ping := btcmsg.NewPingMsg().(*btcmsg.Message_ping)
ping.Nonce = uint64(p.handle)
p.sendMsg(ping, 0, nil)
case <-p.kickTimer.C:
p.kick()
case <-p.done:
running = false
}
}
p.cleanUp()
}
func (p *Peer) sendVersionMsg() error {
vmsg := btcmsg.NewLocalVersionMsg(p.info)
return btcmsg.WriteMsg(p.conn, vmsg)
}