package main import ( "context" "fmt" "os" gosignal "os/signal" "github.com/docker/docker/pkg/signal" "github.com/docker/docker/pkg/term" "github.com/pkg/errors" "github.com/projectatomic/libpod/libpod" "github.com/sirupsen/logrus" "golang.org/x/crypto/ssh/terminal" "k8s.io/client-go/tools/remotecommand" ) type RawTtyFormatter struct { } // Start (if required) and attach to a container func startAttachCtr(ctr *libpod.Container, stdout, stderr, stdin *os.File, detachKeys string, sigProxy bool, startContainer bool) error { ctx := context.Background() resize := make(chan remotecommand.TerminalSize) haveTerminal := terminal.IsTerminal(int(os.Stdin.Fd())) // Check if we are attached to a terminal. If we are, generate resize // events, and set the terminal to raw mode if haveTerminal && ctr.Spec().Process.Terminal { logrus.Debugf("Handling terminal attach") subCtx, cancel := context.WithCancel(ctx) defer cancel() resizeTty(subCtx, resize) oldTermState, err := term.SaveState(os.Stdin.Fd()) if err != nil { return errors.Wrapf(err, "unable to save terminal state") } logrus.SetFormatter(&RawTtyFormatter{}) term.SetRawTerminal(os.Stdin.Fd()) defer restoreTerminal(oldTermState) } streams := new(libpod.AttachStreams) streams.OutputStream = stdout streams.ErrorStream = stderr streams.InputStream = stdin streams.AttachOutput = true streams.AttachError = true streams.AttachInput = true if stdout == nil { logrus.Debugf("Not attaching to stdout") streams.AttachOutput = false } if stderr == nil { logrus.Debugf("Not attaching to stderr") streams.AttachError = false } if stdin == nil { logrus.Debugf("Not attaching to stdin") streams.AttachInput = false } if !startContainer { if sigProxy { ProxySignals(ctr) } return ctr.Attach(streams, detachKeys, resize) } attachChan, err := ctr.StartAndAttach(getContext(), streams, detachKeys, resize) if err != nil { return err } if sigProxy { ProxySignals(ctr) } if stdout == nil && stderr == nil { fmt.Printf("%s\n", ctr.ID()) } err = <-attachChan if err != nil { return errors.Wrapf(err, "error attaching to container %s", ctr.ID()) } return nil } // getResize returns a TerminalSize command matching stdin's current // size on success, and nil on errors. func getResize() *remotecommand.TerminalSize { winsize, err := term.GetWinsize(os.Stdin.Fd()) if err != nil { logrus.Warnf("Could not get terminal size %v", err) return nil } return &remotecommand.TerminalSize{ Width: winsize.Width, Height: winsize.Height, } } // Helper for prepareAttach - set up a goroutine to generate terminal resize events func resizeTty(ctx context.Context, resize chan remotecommand.TerminalSize) { sigchan := make(chan os.Signal, 1) gosignal.Notify(sigchan, signal.SIGWINCH) go func() { defer close(resize) // Update the terminal size immediately without waiting // for a SIGWINCH to get the correct initial size. resizeEvent := getResize() for { if resizeEvent == nil { select { case <-ctx.Done(): return case <-sigchan: resizeEvent = getResize() } } else { select { case <-ctx.Done(): return case <-sigchan: resizeEvent = getResize() case resize <- *resizeEvent: resizeEvent = nil } } } }() } func restoreTerminal(state *term.State) error { logrus.SetFormatter(&logrus.TextFormatter{}) return term.RestoreTerminal(os.Stdin.Fd(), state) } func (f *RawTtyFormatter) Format(entry *logrus.Entry) ([]byte, error) { textFormatter := logrus.TextFormatter{} bytes, err := textFormatter.Format(entry) if err == nil { bytes = append(bytes, '\r') } return bytes, err }