func receiveTTY(usock *unixsocket.Usock, err error) (*os.File, error) {
if err != nil {
return nil, err
}
clientFd, err := usock.ReadFD()
if err != nil {
return nil, errors.New("Expected FD, none received!")
}
fileName := strconv.Itoa(rand.Int())
clientFile := unixsocket.FdToFile(clientFd, fileName)
return clientFile, nil
}
// This should only be called while holding a lock on s.L.
// This unfortunately holds the mutex for a little while, and if the
// command dies super early, the entire slave pretty well deadlocks.
// TODO: review this.
func (s *SlaveNode) bootCommand(request *CommandRequest) {
identifier := request.Name
// TODO: If crashed, do something different...
msg := messages.CreateSpawnCommandMessage(identifier)
_, err := s.socket.WriteMessage(msg)
if err != nil {
slog.Error(err)
return
}
commandFD, err := s.socket.ReadFD()
if err != nil {
fmt.Println(s.socket)
slog.Error(err)
return
}
fileName := strconv.Itoa(rand.Int())
commandFile := unixsocket.FdToFile(commandFD, fileName)
request.Retchan <- commandFile
}
func (mon *SlaveMonitor) slaveDidBeginRegistration(fd int) {
// Having just started the process, we expect an IO, which we convert to a UNIX domain socket
fileName := strconv.Itoa(rand.Int())
slaveFile := unixsocket.FdToFile(fd, fileName)
slaveUsock, err := unixsocket.NewUsockFromFile(slaveFile)
if err != nil {
slog.Error(err)
}
if err = slaveUsock.Conn.SetReadBuffer(1024); err != nil {
slog.Error(err)
}
if err = slaveUsock.Conn.SetWriteBuffer(1024); err != nil {
slog.Error(err)
}
// We now expect the slave to use this fd they send us to send a Pid&Identifier Message
msg, err := slaveUsock.ReadMessage()
if err != nil {
slog.Error(err)
}
pid, identifier, err := messages.ParsePidMessage(msg)
// And the last step before executing its action, the slave sends us a pipe it will later use to
// send us all the features it's loaded.
featurePipeFd, err := slaveUsock.ReadFD()
if err != nil {
slog.Error(err)
}
slaveNode := mon.tree.FindSlaveByName(identifier)
if slaveNode == nil {
Error("slavemonitor.go:slaveDidBeginRegistration:Unknown identifier:" + identifier)
}
slaveNode.SlaveWasInitialized(pid, slaveUsock, featurePipeFd)
}