func (c *cwrapperImpl) init(msg *logger.Logger) error {
var err error
if spawnCwrapper {
err = c.startCWrapper(msg)
if err != nil {
return err
}
} else {
go func() {
c.quit <- struct{}{}
}()
}
msg.Infof("... starting tcp server ...\n")
c.lst, err = net.Listen("tcp", fmt.Sprintf(":%d", c.port))
if err != nil {
msg.Errorf("error starting tcp server: %v\n", err)
return err
}
msg.Infof("... waiting for a connection ...\n")
c.conn, err = c.lst.Accept()
if err != nil {
msg.Errorf("error accepting connection: %v\n", err)
return err
}
return err
}
func (c *cwrapperImpl) startCWrapper(msg *logger.Logger) error {
host, err := c.host(msg)
if err != nil {
return err
}
msg.Infof("Starting c-wrapper on PC-104... (listen for %s:%d)\n", host, c.port)
cmd := exec.Command(
"ssh",
"-X",
"*****@*****.**",
"/root/bin/startCWrapper --host="+host, fmt.Sprintf("--port=%d", c.port),
)
cmd.Env = os.Environ()
cmd.Env = append(cmd.Env, "TERM=vt100")
//cmd.Stdin = os.Stdin
//cmd.Stdout = os.Stderr
//cmd.Stderr = os.Stderr
cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true}
msg.Infof("c-wrapper command: %v\n", cmd.Args)
c.proc = cmd
err = c.proc.Start()
if err != nil {
msg.Errorf("error starting c-wrapper: %v\n", err)
return err
}
go func() {
select {
case <-c.quit:
c.errc <- c.proc.Process.Kill()
}
}()
return err
}
func (c *cwrapperImpl) host(msg *logger.Logger) (string, error) {
host, err := os.Hostname()
if err != nil {
msg.Errorf("could not retrieve hostname: %v\n", err)
return "", err
}
addrs, err := net.LookupIP(host)
if err != nil {
msg.Errorf("could not lookup hostname IP: %v\n", err)
return "", err
}
for _, addr := range addrs {
ipv4 := addr.To4()
if ipv4 == nil {
continue
}
return ipv4.String(), nil
}
msg.Errorf("could not infer host IP")
return "", fmt.Errorf("could not infer host IP")
}