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package hub
import (
"blicky.net/asyncwr"
"blicky.net/tanja"
"errors"
"globster/adc"
"net"
"time"
)
type hub struct {
name string
ses *tanja.Session
// Only set in the connected state, nil otherwise.
conn net.Conn
wr *adc.Writer
rd <-chan *adc.Message
// Channel for the asynchronous connect. Only set in the connecting state,
// otherwise nil. Only one value is written to the channel, a net.Conn on
// success or an error otherwise.
connCh <-chan interface{}
// ADC info (only useful if conn != nil)
state adc.State
mysid string
}
func newHub(node *tanja.Node, name string) *hub {
s := &hub{name: name, ses: node.Session()}
s.ses.RegRPC(s, func(s string) tanja.Tuple {
if s[0] != 'T' {
return nil
}
return tanja.Tup("hub", name, s[1:])
})
s.ses.Send(false, "hub", name, "Created")
go func() {
for {
select {
case m, ok := <-s.ses.Chan():
if !ok {
return
}
m.Dispatch()
case m := <-s.rd:
if m == nil {
s.rd = nil
} else if err := adc.HandleHub(m, s.state, s); err != nil {
s.ses.Send(false, "hub", s.name, "disconnect", err.Error())
}
case c := <-s.connCh:
s.connected(c)
}
}
s.ses.Run()
}()
return s
}
func (s *hub) Texists(m *tanja.Message) {
m.Reply(s.name)
m.Close()
}
func (s *hub) Tconnect(addr string) {
if s.conn != nil || s.connCh != nil {
return
}
ch := make(chan interface{}, 2)
s.connCh = ch
go func() {
c, e := net.DialTimeout("tcp", addr, 30*time.Second)
if e != nil {
ch <- e
} else {
ch <- c
}
}()
}
// Sending 'disconnect' will immediately put the hub into disconnected state,
// but the actual disconnect from the hub may take a while. The "Disconnected"
// notification is sent immediately, but the return path is only closed after
// the disconnect has been completed.
func (s *hub) Tdisconnect(m *tanja.Message, r ...tanja.Element) {
broadcast := false
if s.connCh != nil {
broadcast = true
// If we're in the connecting state, set connCh to nil so we won't be
// getting its result. In case the connection was successful, make sure
// to immediately disconnect again.
go func(ch <-chan interface{}) {
if c, ok := (<-ch).(net.Conn); ok {
c.Close()
}
}(s.connCh)
s.connCh = nil
m.Close()
} else if s.conn != nil {
broadcast = true
// If we're connected, close the connection.
go func(c net.Conn) {
c.Close()
m.Close()
}(s.conn)
s.conn = nil
s.wr = nil
// Also drain the reader channel (to make sure the reader goroutine doesn't deadlock)
if s.rd != nil {
go func(ch <-chan *adc.Message) {
for _ = range ch {
}
}(s.rd)
s.rd = nil
}
} else {
m.Close()
}
if broadcast {
s.ses.Sendt(false, append(tanja.Tup("hub", s.name, "Disconnected"), r...))
}
}
func (s *hub) connected(r interface{}) {
s.connCh = nil
if e, ok := r.(error); ok {
s.ses.Send(false, "hub", s.name, "Disconnected", e.Error())
return
}
// Successful connect
s.conn = r.(net.Conn)
s.ses.Send(false, "hub", s.name, "Connected", s.conn.RemoteAddr().String())
s.wr = adc.NewWriter(asyncwr.New(s.conn, 1024*1024))
// Start reader goroutine
ch := make(chan *adc.Message, 10)
s.rd = ch
go func(rd *adc.Reader) {
for {
m, err := rd.Read()
if err != nil {
s.ses.Send(false, "hub", s.name, "disconnect", err.Error())
break
} else if m != nil {
ch <- m
}
}
close(ch)
}(adc.NewReader(s.conn, 100*1024))
// Initiate handshake
s.state = adc.PROTOCOL
s.wr.Write(adc.NewMessage('H', adc.SUP).AddNamed("AD", "BASE").AddNamed("AD", "TIGR"))
}
func (s *hub) AdcSUP(ad []string, rm []string) error {
if s.state != adc.PROTOCOL || len(rm) > 0 {
return errors.New("Dynamic changing of protocol features is not supported")
}
hasbase, hastigr := false, false
for _, v := range ad {
if string(v) == "BASE" {
hasbase = true
} else if string(v) == "TIGR" {
hastigr = true
}
}
if !hasbase || !hastigr {
return errors.New("Hub does not support BASE or TIGR")
}
return nil
}
func (s *hub) AdcSID(sid string) error {
s.mysid = sid
s.state = adc.IDENTIFY
return nil
}
func (s *hub) close() {
r := s.ses.Send(true, "hub", s.name, "disconnect")
<-r.Chan()
r.Close()
s.ses.Close()
s.ses.Send(false, "hub", s.name, "Closed")
}
|
