Function setupIO

utils_linux.go:99–158

setupIO modifies the given process config according to the options.

(process *libcontainer.Process, container *libcontainer.Container, createTTY, detach bool, sockpath string)

// setupIO modifies the given process config according to the options.
func setupIO(process *libcontainer.Process, container *libcontainer.Container, createTTY, detach bool, sockpath string) (_ *tty, Err error) {
	if createTTY {
		process.Stdin = nil
		process.Stdout = nil
		process.Stderr = nil
		t := &tty{}
		if !detach {
			if err := t.initHostConsole(); err != nil {
				return nil, err
			}
			parent, child, err := utils.NewSockPair("console")
			if err != nil {
				return nil, err
			}
			process.ConsoleSocket = child
			t.postStart = append(t.postStart, parent, child)
			t.consoleC = make(chan error, 1)
			go func() {
				t.consoleC <- t.recvtty(parent)
			}()
		} else {
			// the caller of runc will handle receiving the console master
			conn, err := net.Dial("unix", sockpath)
			if err != nil {
				return nil, err
			}
			defer func() {
				if Err != nil {
					conn.Close()
				}
			}()
			t.postStart = append(t.postStart, conn)
			socket, err := conn.(*net.UnixConn).File()
			if err != nil {
				return nil, err
			}
			t.postStart = append(t.postStart, socket)
			process.ConsoleSocket = socket
		}
		return t, nil
	}
	// when runc will detach the caller provides the stdio to runc via runc's 0,1,2
	// and the container's process inherits runc's stdio.
	if detach {
		inheritStdio(process)
		return &tty{}, nil
	}

	config := container.Config()
	rootuid, err := config.HostRootUID()
	if err != nil {
		return nil, err
	}
	rootgid, err := config.HostRootGID()
	if err != nil {
		return nil, err
	}