示例#1
0
文件: exec.go 项目: beginnor/docker
// the process for execing a new process inside an existing container is that we have to exec ourself
// with the nsenter argument so that the C code can setns an the namespaces that we require.  Then that
// code path will drop us into the path that we can do the final setup of the namespace and exec the users
// application.
func startInExistingContainer(config *libcontainer.Config, state *libcontainer.State, action string, context *cli.Context) (int, error) {
	var (
		master  *os.File
		console string
		err     error

		sigc = make(chan os.Signal, 10)

		stdin  = os.Stdin
		stdout = os.Stdout
		stderr = os.Stderr
	)
	signal.Notify(sigc)

	if config.Tty {
		stdin = nil
		stdout = nil
		stderr = nil

		master, console, err = consolepkg.CreateMasterAndConsole()
		if err != nil {
			return -1, err
		}

		go io.Copy(master, os.Stdin)
		go io.Copy(os.Stdout, master)

		state, err := term.SetRawTerminal(os.Stdin.Fd())
		if err != nil {
			return -1, err
		}

		defer term.RestoreTerminal(os.Stdin.Fd(), state)
	}

	startCallback := func(cmd *exec.Cmd) {
		go func() {
			resizeTty(master)

			for sig := range sigc {
				switch sig {
				case syscall.SIGWINCH:
					resizeTty(master)
				default:
					cmd.Process.Signal(sig)
				}
			}
		}()
	}

	return namespaces.ExecIn(config, state, context.Args(), os.Args[0], action, stdin, stdout, stderr, console, startCallback)
}
示例#2
0
文件: hijack.go 项目: beginnor/docker
func (cli *DockerCli) hijack(method, path string, setRawTerminal bool, in io.ReadCloser, stdout, stderr io.Writer, started chan io.Closer) error {
	defer func() {
		if started != nil {
			close(started)
		}
	}()

	req, err := http.NewRequest(method, fmt.Sprintf("/v%s%s", api.APIVERSION, path), nil)
	if err != nil {
		return err
	}
	req.Header.Set("User-Agent", "Docker-Client/"+dockerversion.VERSION)
	req.Header.Set("Content-Type", "plain/text")
	req.Host = cli.addr

	dial, err := cli.dial()
	if err != nil {
		if strings.Contains(err.Error(), "connection refused") {
			return fmt.Errorf("Cannot connect to the Docker daemon. Is 'docker -d' running on this host?")
		}
		return err
	}
	clientconn := httputil.NewClientConn(dial, nil)
	defer clientconn.Close()

	// Server hijacks the connection, error 'connection closed' expected
	clientconn.Do(req)

	rwc, br := clientconn.Hijack()
	defer rwc.Close()

	if started != nil {
		started <- rwc
	}

	var receiveStdout chan error

	var oldState *term.State

	if in != nil && setRawTerminal && cli.isTerminal && os.Getenv("NORAW") == "" {
		oldState, err = term.SetRawTerminal(cli.terminalFd)
		if err != nil {
			return err
		}
		defer term.RestoreTerminal(cli.terminalFd, oldState)
	}

	if stdout != nil || stderr != nil {
		receiveStdout = utils.Go(func() (err error) {
			defer func() {
				if in != nil {
					if setRawTerminal && cli.isTerminal {
						term.RestoreTerminal(cli.terminalFd, oldState)
					}
					// For some reason this Close call blocks on darwin..
					// As the client exists right after, simply discard the close
					// until we find a better solution.
					if runtime.GOOS != "darwin" {
						in.Close()
					}
				}
			}()

			// When TTY is ON, use regular copy
			if setRawTerminal && stdout != nil {
				_, err = io.Copy(stdout, br)
			} else {
				_, err = utils.StdCopy(stdout, stderr, br)
			}
			log.Debugf("[hijack] End of stdout")
			return err
		})
	}

	sendStdin := utils.Go(func() error {
		if in != nil {
			io.Copy(rwc, in)
			log.Debugf("[hijack] End of stdin")
		}
		if tcpc, ok := rwc.(*net.TCPConn); ok {
			if err := tcpc.CloseWrite(); err != nil {
				log.Debugf("Couldn't send EOF: %s", err)
			}
		} else if unixc, ok := rwc.(*net.UnixConn); ok {
			if err := unixc.CloseWrite(); err != nil {
				log.Debugf("Couldn't send EOF: %s", err)
			}
		}
		// Discard errors due to pipe interruption
		return nil
	})

	if stdout != nil || stderr != nil {
		if err := <-receiveStdout; err != nil {
			log.Debugf("Error receiveStdout: %s", err)
			return err
		}
	}

	if !cli.isTerminal {
		if err := <-sendStdin; err != nil {
			log.Debugf("Error sendStdin: %s", err)
			return err
		}
	}
	return nil
}
示例#3
0
文件: exec.go 项目: beginnor/docker
// startContainer starts the container. Returns the exit status or -1 and an
// error.
//
// Signals sent to the current process will be forwarded to container.
func startContainer(container *libcontainer.Config, dataPath string, args []string) (int, error) {
	var (
		cmd  *exec.Cmd
		sigc = make(chan os.Signal, 10)
	)

	signal.Notify(sigc)

	createCommand := func(container *libcontainer.Config, console, rootfs, dataPath, init string, pipe *os.File, args []string) *exec.Cmd {
		cmd = namespaces.DefaultCreateCommand(container, console, rootfs, dataPath, init, pipe, args)
		if logPath != "" {
			cmd.Env = append(cmd.Env, fmt.Sprintf("log=%s", logPath))
		}
		return cmd
	}

	var (
		master  *os.File
		console string
		err     error

		stdin  = os.Stdin
		stdout = os.Stdout
		stderr = os.Stderr
	)

	if container.Tty {
		stdin = nil
		stdout = nil
		stderr = nil

		master, console, err = consolepkg.CreateMasterAndConsole()
		if err != nil {
			return -1, err
		}

		go io.Copy(master, os.Stdin)
		go io.Copy(os.Stdout, master)

		state, err := term.SetRawTerminal(os.Stdin.Fd())
		if err != nil {
			return -1, err
		}

		defer term.RestoreTerminal(os.Stdin.Fd(), state)
	}

	startCallback := func() {
		go func() {
			resizeTty(master)

			for sig := range sigc {
				switch sig {
				case syscall.SIGWINCH:
					resizeTty(master)
				default:
					cmd.Process.Signal(sig)
				}
			}
		}()
	}

	return namespaces.Exec(container, stdin, stdout, stderr, console, "", dataPath, args, createCommand, startCallback)
}