func epmdC(n *Node, resp chan uint16) {
conn, err := net.Dial("tcp", ":4369")
if err != nil {
resp <- 100
return
}
defer conn.Close()
epmdFROM := make(chan []byte)
go epmdREADER(conn, epmdFROM)
epmdTO := make(chan []byte)
go epmdWRITER(conn, epmdFROM, epmdTO)
epmdTO <- epmd.Compose_ALIVE2_REQ(&n.NodeInfo)
for {
select {
case reply := <-epmdFROM:
nLog("From EPMD: %v", reply)
switch epmd.MessageId(reply[0]) {
case epmd.ALIVE2_RESP:
if creation, ok := epmd.Read_ALIVE2_RESP(reply); ok {
resp <- creation
} else {
resp <- 99
}
}
}
}
}
func epmReg(in <-chan regReq) {
var nReg = make(map[string]*nodeRec)
for {
select {
case req := <-in:
buf := req.buf
if len(buf) == 0 {
rs := len(nReg)
log.Printf("REG %d records", rs)
now := time.Now()
for node, rec := range nReg {
if rec.conn == req.conn {
log.Printf("Connection for %s dropped", node)
nReg[node].Active = false
nReg[node].Time = now
nReg[node].conn = nil
} else if rs > regLimit && !rec.Active && now.Sub(rec.Time).Minutes() > float64(unregTTL) {
log.Printf("REG prune %s:%+v", node, rec)
delete(nReg, node)
}
}
continue
}
replyTo := req.replyTo
log.Printf("IN: %v", buf)
switch epmd.MessageId(buf[0]) {
case epmd.ALIVE2_REQ:
nConn := req.conn
nInfo := epmd.Read_ALIVE2_REQ(buf)
log.Printf("NodeInfo: %+v", nInfo)
var reply []byte
if rec, ok := nReg[nInfo.Name]; ok {
log.Printf("Node %s found", nInfo.Name)
if rec.Active {
log.Printf("Node %s is running", nInfo.Name)
reply = epmd.Compose_ALIVE2_RESP(false)
} else {
log.Printf("Node %s is not running", nInfo.Name)
rec.conn = nConn
nInfo.Creation = (rec.Creation % 3) + 1
rec.NodeInfo = nInfo
rec.Active = true
reply = epmd.Compose_ALIVE2_RESP(true, rec.NodeInfo)
}
} else {
log.Printf("New node %s", nInfo.Name)
nInfo.Creation = 1
rec := &nodeRec{
NodeInfo: nInfo,
conn: nConn,
Time: time.Now(),
Active: true,
}
nReg[nInfo.Name] = rec
reply = epmd.Compose_ALIVE2_RESP(true, rec.NodeInfo)
}
replyTo <- regAns{reply: reply, isClose: false}
case epmd.PORT_PLEASE2_REQ:
nName := epmd.Read_PORT_PLEASE2_REQ(buf)
var reply []byte
if rec, ok := nReg[nName]; ok && rec.Active {
reply = epmd.Compose_PORT2_RESP(rec.NodeInfo)
} else {
reply = epmd.Compose_PORT2_RESP(nil)
}
replyTo <- regAns{reply: reply, isClose: true}
case epmd.STOP_REQ:
nName := epmd.Read_STOP_REQ(buf)
var reply []byte
if rec, ok := nReg[nName]; ok && rec.Active {
// TODO: stop node
reply = epmd.Compose_STOP_RESP(true)
} else {
reply = epmd.Compose_STOP_RESP(false)
}
replyTo <- regAns{reply: reply, isClose: true}
case epmd.NAMES_REQ, epmd.DUMP_REQ:
lp, err := strconv.Atoi(listenPort)
if err != nil {
log.Printf("Cannot convert %s to integer", listenPort)
replyTo <- regAns{reply: nil, isClose: true}
} else {
replyB := new(bytes.Buffer)
epmd.Compose_START_NAMES_RESP(replyB, lp)
for _, rec := range nReg {
if epmd.MessageId(buf[0]) == epmd.NAMES_REQ {
if rec.Active {
epmd.Append_NAMES_RESP(replyB, rec.NodeInfo)
} else {
if rec.Active {
epmd.Append_DUMP_RESP_ACTIVE(replyB, rec.NodeInfo)
} else {
epmd.Append_DUMP_RESP_UNUSED(replyB, rec.NodeInfo)
}
}
}
}
replyTo <- regAns{reply: replyB.Bytes(), isClose: true}
}
case epmd.KILL_REQ:
reply := epmd.Compose_KILL_RESP()
replyTo <- regAns{reply: reply, isClose: true}
default:
switch cliMessageId(buf[0]) {
case REQ_NAMES:
reply := ansNames(nReg)
replyTo <- regAns{reply: reply, isClose: true}
default:
replyTo <- regAns{reply: nil, isClose: true}
}
}
}
}
}