moby/api/client/commands.go

package client

import (
	"bufio"
	"bytes"
	"encoding/base64"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"io/ioutil"
	"net/http"
	"net/url"
	"os"
	"os/exec"
	"path"
	"path/filepath"
	"runtime"
	"strconv"
	"strings"
	"text/tabwriter"
	"text/template"
	"time"

	log "github.com/Sirupsen/logrus"
	"github.com/docker/docker/api"
	"github.com/docker/docker/dockerversion"
	"github.com/docker/docker/engine"
	"github.com/docker/docker/graph"
	"github.com/docker/docker/nat"
	"github.com/docker/docker/opts"
	"github.com/docker/docker/pkg/archive"
	flag "github.com/docker/docker/pkg/mflag"
	"github.com/docker/docker/pkg/parsers"
	"github.com/docker/docker/pkg/parsers/filters"
	"github.com/docker/docker/pkg/promise"
	"github.com/docker/docker/pkg/signal"
	"github.com/docker/docker/pkg/term"
	"github.com/docker/docker/pkg/timeutils"
	"github.com/docker/docker/pkg/units"
	"github.com/docker/docker/pkg/urlutil"
	"github.com/docker/docker/registry"
	"github.com/docker/docker/runconfig"
	"github.com/docker/docker/utils"
)

const (
	tarHeaderSize = 512
)

var (
	acceptedImageFilterTags = map[string]struct{}{"dangling": {}}
)

func (cli *DockerCli) CmdHelp(args ...string) error {
	if len(args) > 1 {
		method, exists := cli.getMethod(args[:2]...)
		if exists {
			method("--help")
			return nil
		}
	}
	if len(args) > 0 {
		method, exists := cli.getMethod(args[0])
		if !exists {
			fmt.Fprintf(cli.err, "Error: Command not found: %s\n", args[0])
		} else {
			method("--help")
			return nil
		}
	}

	flag.Usage()

	return nil
}

func (cli *DockerCli) CmdBuild(args ...string) error {
	cmd := cli.Subcmd("build", "PATH | URL | -", "Build a new image from the source code at PATH")
	tag := cmd.String([]string{"t", "-tag"}, "", "Repository name (and optionally a tag) to be applied to the resulting image in case of success")
	suppressOutput := cmd.Bool([]string{"q", "-quiet"}, false, "Suppress the verbose output generated by the containers")
	noCache := cmd.Bool([]string{"#no-cache", "-no-cache"}, false, "Do not use cache when building the image")
	rm := cmd.Bool([]string{"#rm", "-rm"}, true, "Remove intermediate containers after a successful build")
	forceRm := cmd.Bool([]string{"-force-rm"}, false, "Always remove intermediate containers, even after unsuccessful builds")
	pull := cmd.Bool([]string{"-pull"}, false, "Always attempt to pull a newer version of the image")
	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() != 1 {
		cmd.Usage()
		return nil
	}

	var (
		context  archive.Archive
		isRemote bool
		err      error
	)

	_, err = exec.LookPath("git")
	hasGit := err == nil
	if cmd.Arg(0) == "-" {
		// As a special case, 'docker build -' will build from either an empty context with the
		// contents of stdin as a Dockerfile, or a tar-ed context from stdin.
		buf := bufio.NewReader(cli.in)
		magic, err := buf.Peek(tarHeaderSize)
		if err != nil && err != io.EOF {
			return fmt.Errorf("failed to peek context header from STDIN: %v", err)
		}
		if !archive.IsArchive(magic) {
			dockerfile, err := ioutil.ReadAll(buf)
			if err != nil {
				return fmt.Errorf("failed to read Dockerfile from STDIN: %v", err)
			}
			context, err = archive.Generate("Dockerfile", string(dockerfile))
		} else {
			context = ioutil.NopCloser(buf)
		}
	} else if urlutil.IsURL(cmd.Arg(0)) && (!urlutil.IsGitURL(cmd.Arg(0)) || !hasGit) {
		isRemote = true
	} else {
		root := cmd.Arg(0)
		if urlutil.IsGitURL(root) {
			remoteURL := cmd.Arg(0)
			if !urlutil.IsGitTransport(remoteURL) {
				remoteURL = "https://" + remoteURL
			}

			root, err = ioutil.TempDir("", "docker-build-git")
			if err != nil {
				return err
			}
			defer os.RemoveAll(root)

			if output, err := exec.Command("git", "clone", "--recursive", remoteURL, root).CombinedOutput(); err != nil {
				return fmt.Errorf("Error trying to use git: %s (%s)", err, output)
			}
		}
		if _, err := os.Stat(root); err != nil {
			return err
		}
		filename := path.Join(root, "Dockerfile")
		if _, err = os.Stat(filename); os.IsNotExist(err) {
			return fmt.Errorf("no Dockerfile found in %s", cmd.Arg(0))
		}
		var excludes []string
		ignore, err := ioutil.ReadFile(path.Join(root, ".dockerignore"))
		if err != nil && !os.IsNotExist(err) {
			return fmt.Errorf("Error reading .dockerignore: '%s'", err)
		}
		for _, pattern := range strings.Split(string(ignore), "\n") {
			pattern = strings.TrimSpace(pattern)
			if pattern == "" {
				continue
			}
			pattern = filepath.Clean(pattern)
			ok, err := filepath.Match(pattern, "Dockerfile")
			if err != nil {
				return fmt.Errorf("Bad .dockerignore pattern: '%s', error: %s", pattern, err)
			}
			if ok {
				return fmt.Errorf("Dockerfile was excluded by .dockerignore pattern '%s'", pattern)
			}
			excludes = append(excludes, pattern)
		}
		if err = utils.ValidateContextDirectory(root, excludes); err != nil {
			return fmt.Errorf("Error checking context is accessible: '%s'. Please check permissions and try again.", err)
		}
		options := &archive.TarOptions{
			Compression: archive.Uncompressed,
			Excludes:    excludes,
		}
		context, err = archive.TarWithOptions(root, options)
		if err != nil {
			return err
		}
	}
	var body io.Reader
	// Setup an upload progress bar
	// FIXME: ProgressReader shouldn't be this annoying to use
	if context != nil {
		sf := utils.NewStreamFormatter(false)
		body = utils.ProgressReader(context, 0, cli.out, sf, true, "", "Sending build context to Docker daemon")
	}
	// Send the build context
	v := &url.Values{}

	//Check if the given image name can be resolved
	if *tag != "" {
		repository, tag := parsers.ParseRepositoryTag(*tag)
		if _, _, err := registry.ResolveRepositoryName(repository); err != nil {
			return err
		}
		if len(tag) > 0 {
			if err := graph.ValidateTagName(tag); err != nil {
				return err
			}
		}
	}

	v.Set("t", *tag)

	if *suppressOutput {
		v.Set("q", "1")
	}
	if isRemote {
		v.Set("remote", cmd.Arg(0))
	}
	if *noCache {
		v.Set("nocache", "1")
	}
	if *rm {
		v.Set("rm", "1")
	} else {
		v.Set("rm", "0")
	}

	if *forceRm {
		v.Set("forcerm", "1")
	}

	if *pull {
		v.Set("pull", "1")
	}
	cli.LoadConfigFile()

	headers := http.Header(make(map[string][]string))
	buf, err := json.Marshal(cli.configFile)
	if err != nil {
		return err
	}
	headers.Add("X-Registry-Config", base64.URLEncoding.EncodeToString(buf))

	if context != nil {
		headers.Set("Content-Type", "application/tar")
	}
	err = cli.stream("POST", fmt.Sprintf("/build?%s", v.Encode()), body, cli.out, headers)
	if jerr, ok := err.(*utils.JSONError); ok {
		// If no error code is set, default to 1
		if jerr.Code == 0 {
			jerr.Code = 1
		}
		return &utils.StatusError{Status: jerr.Message, StatusCode: jerr.Code}
	}
	return err
}

// 'docker login': login / register a user to registry service.
func (cli *DockerCli) CmdLogin(args ...string) error {
	cmd := cli.Subcmd("login", "[SERVER]", "Register or log in to a Docker registry server, if no server is specified \""+registry.IndexServerAddress()+"\" is the default.")

	var username, password, email string

	cmd.StringVar(&username, []string{"u", "-username"}, "", "Username")
	cmd.StringVar(&password, []string{"p", "-password"}, "", "Password")
	cmd.StringVar(&email, []string{"e", "-email"}, "", "Email")
	err := cmd.Parse(args)
	if err != nil {
		return nil
	}
	serverAddress := registry.IndexServerAddress()
	if len(cmd.Args()) > 0 {
		serverAddress = cmd.Arg(0)
	}

	promptDefault := func(prompt string, configDefault string) {
		if configDefault == "" {
			fmt.Fprintf(cli.out, "%s: ", prompt)
		} else {
			fmt.Fprintf(cli.out, "%s (%s): ", prompt, configDefault)
		}
	}

	readInput := func(in io.Reader, out io.Writer) string {
		reader := bufio.NewReader(in)
		line, _, err := reader.ReadLine()
		if err != nil {
			fmt.Fprintln(out, err.Error())
			os.Exit(1)
		}
		return string(line)
	}

	cli.LoadConfigFile()
	authconfig, ok := cli.configFile.Configs[serverAddress]
	if !ok {
		authconfig = registry.AuthConfig{}
	}

	if username == "" {
		promptDefault("Username", authconfig.Username)
		username = readInput(cli.in, cli.out)
		if username == "" {
			username = authconfig.Username
		}
	}
	// Assume that a different username means they may not want to use
	// the password or email from the config file, so prompt them
	if username != authconfig.Username {
		if password == "" {
			oldState, err := term.SaveState(cli.inFd)
			if err != nil {
				return err
			}
			fmt.Fprintf(cli.out, "Password: ")
			term.DisableEcho(cli.inFd, oldState)

			password = readInput(cli.in, cli.out)
			fmt.Fprint(cli.out, "\n")

			term.RestoreTerminal(cli.inFd, oldState)
			if password == "" {
				return fmt.Errorf("Error : Password Required")
			}
		}

		if email == "" {
			promptDefault("Email", authconfig.Email)
			email = readInput(cli.in, cli.out)
			if email == "" {
				email = authconfig.Email
			}
		}
	} else {
		// However, if they don't override the username use the
		// password or email from the cmd line if specified. IOW, allow
		// then to change/overide them.  And if not specified, just
		// use what's in the config file
		if password == "" {
			password = authconfig.Password
		}
		if email == "" {
			email = authconfig.Email
		}
	}
	authconfig.Username = username
	authconfig.Password = password
	authconfig.Email = email
	authconfig.ServerAddress = serverAddress
	cli.configFile.Configs[serverAddress] = authconfig

	stream, statusCode, err := cli.call("POST", "/auth", cli.configFile.Configs[serverAddress], false)
	if statusCode == 401 {
		delete(cli.configFile.Configs, serverAddress)
		registry.SaveConfig(cli.configFile)
		return err
	}
	if err != nil {
		return err
	}
	var out2 engine.Env
	err = out2.Decode(stream)
	if err != nil {
		cli.configFile, _ = registry.LoadConfig(os.Getenv("HOME"))
		return err
	}
	registry.SaveConfig(cli.configFile)
	if out2.Get("Status") != "" {
		fmt.Fprintf(cli.out, "%s\n", out2.Get("Status"))
	}
	return nil
}

// log out from a Docker registry
func (cli *DockerCli) CmdLogout(args ...string) error {
	cmd := cli.Subcmd("logout", "[SERVER]", "Log out from a Docker registry, if no server is specified \""+registry.IndexServerAddress()+"\" is the default.")

	if err := cmd.Parse(args); err != nil {
		return nil
	}
	serverAddress := registry.IndexServerAddress()
	if len(cmd.Args()) > 0 {
		serverAddress = cmd.Arg(0)
	}

	cli.LoadConfigFile()
	if _, ok := cli.configFile.Configs[serverAddress]; !ok {
		fmt.Fprintf(cli.out, "Not logged in to %s\n", serverAddress)
	} else {
		fmt.Fprintf(cli.out, "Remove login credentials for %s\n", serverAddress)
		delete(cli.configFile.Configs, serverAddress)

		if err := registry.SaveConfig(cli.configFile); err != nil {
			return fmt.Errorf("Failed to save docker config: %v", err)
		}
	}
	return nil
}

// 'docker wait': block until a container stops
func (cli *DockerCli) CmdWait(args ...string) error {
	cmd := cli.Subcmd("wait", "CONTAINER [CONTAINER...]", "Block until a container stops, then print its exit code.")
	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() < 1 {
		cmd.Usage()
		return nil
	}
	var encounteredError error
	for _, name := range cmd.Args() {
		status, err := waitForExit(cli, name)
		if err != nil {
			fmt.Fprintf(cli.err, "%s\n", err)
			encounteredError = fmt.Errorf("Error: failed to wait one or more containers")
		} else {
			fmt.Fprintf(cli.out, "%d\n", status)
		}
	}
	return encounteredError
}

// 'docker version': show version information
func (cli *DockerCli) CmdVersion(args ...string) error {
	cmd := cli.Subcmd("version", "", "Show the Docker version information.")
	if err := cmd.Parse(args); err != nil {
		return nil
	}

	if cmd.NArg() > 0 {
		cmd.Usage()
		return nil
	}
	if dockerversion.VERSION != "" {
		fmt.Fprintf(cli.out, "Client version: %s\n", dockerversion.VERSION)
	}
	fmt.Fprintf(cli.out, "Client API version: %s\n", api.APIVERSION)
	fmt.Fprintf(cli.out, "Go version (client): %s\n", runtime.Version())
	if dockerversion.GITCOMMIT != "" {
		fmt.Fprintf(cli.out, "Git commit (client): %s\n", dockerversion.GITCOMMIT)
	}
	fmt.Fprintf(cli.out, "OS/Arch (client): %s/%s\n", runtime.GOOS, runtime.GOARCH)

	body, _, err := readBody(cli.call("GET", "/version", nil, false))
	if err != nil {
		return err
	}

	out := engine.NewOutput()
	remoteVersion, err := out.AddEnv()
	if err != nil {
		log.Errorf("Error reading remote version: %s", err)
		return err
	}
	if _, err := out.Write(body); err != nil {
		log.Errorf("Error reading remote version: %s", err)
		return err
	}
	out.Close()
	fmt.Fprintf(cli.out, "Server version: %s\n", remoteVersion.Get("Version"))
	if apiVersion := remoteVersion.Get("ApiVersion"); apiVersion != "" {
		fmt.Fprintf(cli.out, "Server API version: %s\n", apiVersion)
	}
	fmt.Fprintf(cli.out, "Go version (server): %s\n", remoteVersion.Get("GoVersion"))
	fmt.Fprintf(cli.out, "Git commit (server): %s\n", remoteVersion.Get("GitCommit"))
	return nil
}

// 'docker info': display system-wide information.
func (cli *DockerCli) CmdInfo(args ...string) error {
	cmd := cli.Subcmd("info", "", "Display system-wide information")
	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() > 0 {
		cmd.Usage()
		return nil
	}

	body, _, err := readBody(cli.call("GET", "/info", nil, false))
	if err != nil {
		return err
	}

	out := engine.NewOutput()
	remoteInfo, err := out.AddEnv()
	if err != nil {
		return err
	}

	if _, err := out.Write(body); err != nil {
		log.Errorf("Error reading remote info: %s", err)
		return err
	}
	out.Close()

	if remoteInfo.Exists("Containers") {
		fmt.Fprintf(cli.out, "Containers: %d\n", remoteInfo.GetInt("Containers"))
	}
	if remoteInfo.Exists("Images") {
		fmt.Fprintf(cli.out, "Images: %d\n", remoteInfo.GetInt("Images"))
	}
	if remoteInfo.Exists("Driver") {
		fmt.Fprintf(cli.out, "Storage Driver: %s\n", remoteInfo.Get("Driver"))
	}
	if remoteInfo.Exists("DriverStatus") {
		var driverStatus [][2]string
		if err := remoteInfo.GetJson("DriverStatus", &driverStatus); err != nil {
			return err
		}
		for _, pair := range driverStatus {
			fmt.Fprintf(cli.out, " %s: %s\n", pair[0], pair[1])
		}
	}
	if remoteInfo.Exists("ExecutionDriver") {
		fmt.Fprintf(cli.out, "Execution Driver: %s\n", remoteInfo.Get("ExecutionDriver"))
	}
	if remoteInfo.Exists("KernelVersion") {
		fmt.Fprintf(cli.out, "Kernel Version: %s\n", remoteInfo.Get("KernelVersion"))
	}
	if remoteInfo.Exists("OperatingSystem") {
		fmt.Fprintf(cli.out, "Operating System: %s\n", remoteInfo.Get("OperatingSystem"))
	}
	if remoteInfo.Exists("NCPU") {
		fmt.Fprintf(cli.out, "CPUs: %d\n", remoteInfo.GetInt("NCPU"))
	}
	if remoteInfo.Exists("MemTotal") {
		fmt.Fprintf(cli.out, "Total Memory: %s\n", units.BytesSize(float64(remoteInfo.GetInt64("MemTotal"))))
	}
	if remoteInfo.Exists("Name") {
		fmt.Fprintf(cli.out, "Name: %s\n", remoteInfo.Get("Name"))
	}
	if remoteInfo.Exists("ID") {
		fmt.Fprintf(cli.out, "ID: %s\n", remoteInfo.Get("ID"))
	}

	if remoteInfo.GetBool("Debug") || os.Getenv("DEBUG") != "" {
		if remoteInfo.Exists("Debug") {
			fmt.Fprintf(cli.out, "Debug mode (server): %v\n", remoteInfo.GetBool("Debug"))
		}
		fmt.Fprintf(cli.out, "Debug mode (client): %v\n", os.Getenv("DEBUG") != "")
		if remoteInfo.Exists("NFd") {
			fmt.Fprintf(cli.out, "Fds: %d\n", remoteInfo.GetInt("NFd"))
		}
		if remoteInfo.Exists("NGoroutines") {
			fmt.Fprintf(cli.out, "Goroutines: %d\n", remoteInfo.GetInt("NGoroutines"))
		}
		if remoteInfo.Exists("NEventsListener") {
			fmt.Fprintf(cli.out, "EventsListeners: %d\n", remoteInfo.GetInt("NEventsListener"))
		}
		if initSha1 := remoteInfo.Get("InitSha1"); initSha1 != "" {
			fmt.Fprintf(cli.out, "Init SHA1: %s\n", initSha1)
		}
		if initPath := remoteInfo.Get("InitPath"); initPath != "" {
			fmt.Fprintf(cli.out, "Init Path: %s\n", initPath)
		}
		if root := remoteInfo.Get("DockerRootDir"); root != "" {
			fmt.Fprintf(cli.out, "Docker Root Dir: %s\n", root)
		}
	}

	if len(remoteInfo.GetList("IndexServerAddress")) != 0 {
		cli.LoadConfigFile()
		u := cli.configFile.Configs[remoteInfo.Get("IndexServerAddress")].Username
		if len(u) > 0 {
			fmt.Fprintf(cli.out, "Username: %v\n", u)
			fmt.Fprintf(cli.out, "Registry: %v\n", remoteInfo.GetList("IndexServerAddress"))
		}
	}
	if remoteInfo.Exists("MemoryLimit") && !remoteInfo.GetBool("MemoryLimit") {
		fmt.Fprintf(cli.err, "WARNING: No memory limit support\n")
	}
	if remoteInfo.Exists("SwapLimit") && !remoteInfo.GetBool("SwapLimit") {
		fmt.Fprintf(cli.err, "WARNING: No swap limit support\n")
	}
	if remoteInfo.Exists("IPv4Forwarding") && !remoteInfo.GetBool("IPv4Forwarding") {
		fmt.Fprintf(cli.err, "WARNING: IPv4 forwarding is disabled.\n")
	}
	if remoteInfo.Exists("Labels") {
		fmt.Fprintln(cli.out, "Labels:")
		for _, attribute := range remoteInfo.GetList("Labels") {
			fmt.Fprintf(cli.out, " %s\n", attribute)
		}
	}

	return nil
}

func (cli *DockerCli) CmdStop(args ...string) error {
	cmd := cli.Subcmd("stop", "CONTAINER [CONTAINER...]", "Stop a running container by sending SIGTERM and then SIGKILL after a grace period")
	nSeconds := cmd.Int([]string{"t", "-time"}, 10, "Number of seconds to wait for the container to stop before killing it. Default is 10 seconds.")
	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() < 1 {
		cmd.Usage()
		return nil
	}

	v := url.Values{}
	v.Set("t", strconv.Itoa(*nSeconds))

	var encounteredError error
	for _, name := range cmd.Args() {
		_, _, err := readBody(cli.call("POST", "/containers/"+name+"/stop?"+v.Encode(), nil, false))
		if err != nil {
			fmt.Fprintf(cli.err, "%s\n", err)
			encounteredError = fmt.Errorf("Error: failed to stop one or more containers")
		} else {
			fmt.Fprintf(cli.out, "%s\n", name)
		}
	}
	return encounteredError
}

func (cli *DockerCli) CmdRestart(args ...string) error {
	cmd := cli.Subcmd("restart", "CONTAINER [CONTAINER...]", "Restart a running container")
	nSeconds := cmd.Int([]string{"t", "-time"}, 10, "Number of seconds to try to stop for before killing the container. Once killed it will then be restarted. Default is 10 seconds.")
	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() < 1 {
		cmd.Usage()
		return nil
	}

	v := url.Values{}
	v.Set("t", strconv.Itoa(*nSeconds))

	var encounteredError error
	for _, name := range cmd.Args() {
		_, _, err := readBody(cli.call("POST", "/containers/"+name+"/restart?"+v.Encode(), nil, false))
		if err != nil {
			fmt.Fprintf(cli.err, "%s\n", err)
			encounteredError = fmt.Errorf("Error: failed to restart one or more containers")
		} else {
			fmt.Fprintf(cli.out, "%s\n", name)
		}
	}
	return encounteredError
}

func (cli *DockerCli) forwardAllSignals(cid string) chan os.Signal {
	sigc := make(chan os.Signal, 128)
	signal.CatchAll(sigc)
	go func() {
		for s := range sigc {
			if s == signal.SIGCHLD {
				continue
			}
			var sig string
			for sigStr, sigN := range signal.SignalMap {
				if sigN == s {
					sig = sigStr
					break
				}
			}
			if sig == "" {
				log.Errorf("Unsupported signal: %v. Discarding.", s)
			}
			if _, _, err := readBody(cli.call("POST", fmt.Sprintf("/containers/%s/kill?signal=%s", cid, sig), nil, false)); err != nil {
				log.Debugf("Error sending signal: %s", err)
			}
		}
	}()
	return sigc
}

func (cli *DockerCli) CmdStart(args ...string) error {
	var (
		cErr chan error
		tty  bool

		cmd       = cli.Subcmd("start", "CONTAINER [CONTAINER...]", "Restart a stopped container")
		attach    = cmd.Bool([]string{"a", "-attach"}, false, "Attach container's STDOUT and STDERR and forward all signals to the process")
		openStdin = cmd.Bool([]string{"i", "-interactive"}, false, "Attach container's STDIN")
	)

	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() < 1 {
		cmd.Usage()
		return nil
	}

	hijacked := make(chan io.Closer)

	if *attach || *openStdin {
		if cmd.NArg() > 1 {
			return fmt.Errorf("You cannot start and attach multiple containers at once.")
		}

		stream, _, err := cli.call("GET", "/containers/"+cmd.Arg(0)+"/json", nil, false)
		if err != nil {
			return err
		}

		env := engine.Env{}
		if err := env.Decode(stream); err != nil {
			return err
		}
		config := env.GetSubEnv("Config")
		tty = config.GetBool("Tty")

		if !tty {
			sigc := cli.forwardAllSignals(cmd.Arg(0))
			defer signal.StopCatch(sigc)
		}

		var in io.ReadCloser

		v := url.Values{}
		v.Set("stream", "1")

		if *openStdin && config.GetBool("OpenStdin") {
			v.Set("stdin", "1")
			in = cli.in
		}

		v.Set("stdout", "1")
		v.Set("stderr", "1")

		cErr = promise.Go(func() error {
			return cli.hijack("POST", "/containers/"+cmd.Arg(0)+"/attach?"+v.Encode(), tty, in, cli.out, cli.err, hijacked, nil)
		})
	} else {
		close(hijacked)
	}

	// Acknowledge the hijack before starting
	select {
	case closer := <-hijacked:
		// Make sure that the hijack gets closed when returning (results
		// in closing the hijack chan and freeing server's goroutines)
		if closer != nil {
			defer closer.Close()
		}
	case err := <-cErr:
		if err != nil {
			return err
		}
	}

	var encounteredError error
	for _, name := range cmd.Args() {
		_, _, err := readBody(cli.call("POST", "/containers/"+name+"/start", nil, false))
		if err != nil {
			if !*attach || !*openStdin {
				fmt.Fprintf(cli.err, "%s\n", err)
			}
			encounteredError = fmt.Errorf("Error: failed to start one or more containers")
		} else {
			if !*attach || !*openStdin {
				fmt.Fprintf(cli.out, "%s\n", name)
			}
		}
	}
	if encounteredError != nil {
		if *openStdin || *attach {
			cli.in.Close()
		}
		return encounteredError
	}

	if *openStdin || *attach {
		if tty && cli.isTerminalOut {
			if err := cli.monitorTtySize(cmd.Arg(0), false); err != nil {
				log.Errorf("Error monitoring TTY size: %s", err)
			}
		}
		if attchErr := <-cErr; attchErr != nil {
			return attchErr
		}
		_, status, err := getExitCode(cli, cmd.Arg(0))
		if err != nil {
			return err
		}
		if status != 0 {
			return &utils.StatusError{StatusCode: status}
		}
	}
	return nil
}

func (cli *DockerCli) CmdUnpause(args ...string) error {
	cmd := cli.Subcmd("unpause", "CONTAINER", "Unpause all processes within a container")
	if err := cmd.Parse(args); err != nil {
		return nil
	}

	if cmd.NArg() != 1 {
		cmd.Usage()
		return nil
	}

	var encounteredError error
	for _, name := range cmd.Args() {
		if _, _, err := readBody(cli.call("POST", fmt.Sprintf("/containers/%s/unpause", name), nil, false)); err != nil {
			fmt.Fprintf(cli.err, "%s\n", err)
			encounteredError = fmt.Errorf("Error: failed to unpause container named %s", name)
		} else {
			fmt.Fprintf(cli.out, "%s\n", name)
		}
	}
	return encounteredError
}

func (cli *DockerCli) CmdPause(args ...string) error {
	cmd := cli.Subcmd("pause", "CONTAINER", "Pause all processes within a container")
	if err := cmd.Parse(args); err != nil {
		return nil
	}

	if cmd.NArg() != 1 {
		cmd.Usage()
		return nil
	}

	var encounteredError error
	for _, name := range cmd.Args() {
		if _, _, err := readBody(cli.call("POST", fmt.Sprintf("/containers/%s/pause", name), nil, false)); err != nil {
			fmt.Fprintf(cli.err, "%s\n", err)
			encounteredError = fmt.Errorf("Error: failed to pause container named %s", name)
		} else {
			fmt.Fprintf(cli.out, "%s\n", name)
		}
	}
	return encounteredError
}

func (cli *DockerCli) CmdInspect(args ...string) error {
	cmd := cli.Subcmd("inspect", "CONTAINER|IMAGE [CONTAINER|IMAGE...]", "Return low-level information on a container or image")
	tmplStr := cmd.String([]string{"f", "#format", "-format"}, "", "Format the output using the given go template.")
	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() < 1 {
		cmd.Usage()
		return nil
	}

	var tmpl *template.Template
	if *tmplStr != "" {
		var err error
		if tmpl, err = template.New("").Funcs(funcMap).Parse(*tmplStr); err != nil {
			fmt.Fprintf(cli.err, "Template parsing error: %v\n", err)
			return &utils.StatusError{StatusCode: 64,
				Status: "Template parsing error: " + err.Error()}
		}
	}

	indented := new(bytes.Buffer)
	indented.WriteByte('[')
	status := 0

	for _, name := range cmd.Args() {
		obj, _, err := readBody(cli.call("GET", "/containers/"+name+"/json", nil, false))
		if err != nil {
			obj, _, err = readBody(cli.call("GET", "/images/"+name+"/json", nil, false))
			if err != nil {
				if strings.Contains(err.Error(), "No such") {
					fmt.Fprintf(cli.err, "Error: No such image or container: %s\n", name)
				} else {
					fmt.Fprintf(cli.err, "%s", err)
				}
				status = 1
				continue
			}
		}

		if tmpl == nil {
			if err = json.Indent(indented, obj, "", "    "); err != nil {
				fmt.Fprintf(cli.err, "%s\n", err)
				status = 1
				continue
			}
		} else {
			// Has template, will render
			var value interface{}
			if err := json.Unmarshal(obj, &value); err != nil {
				fmt.Fprintf(cli.err, "%s\n", err)
				status = 1
				continue
			}
			if err := tmpl.Execute(cli.out, value); err != nil {
				return err
			}
			cli.out.Write([]byte{'\n'})
		}
		indented.WriteString(",")
	}

	if indented.Len() > 1 {
		// Remove trailing ','
		indented.Truncate(indented.Len() - 1)
	}
	indented.WriteString("]\n")

	if tmpl == nil {
		if _, err := io.Copy(cli.out, indented); err != nil {
			return err
		}
	}

	if status != 0 {
		return &utils.StatusError{StatusCode: status}
	}
	return nil
}

func (cli *DockerCli) CmdTop(args ...string) error {
	cmd := cli.Subcmd("top", "CONTAINER [ps OPTIONS]", "Display the running processes of a container")
	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() == 0 {
		cmd.Usage()
		return nil
	}
	val := url.Values{}
	if cmd.NArg() > 1 {
		val.Set("ps_args", strings.Join(cmd.Args()[1:], " "))
	}

	stream, _, err := cli.call("GET", "/containers/"+cmd.Arg(0)+"/top?"+val.Encode(), nil, false)
	if err != nil {
		return err
	}
	var procs engine.Env
	if err := procs.Decode(stream); err != nil {
		return err
	}
	w := tabwriter.NewWriter(cli.out, 20, 1, 3, ' ', 0)
	fmt.Fprintln(w, strings.Join(procs.GetList("Titles"), "\t"))
	processes := [][]string{}
	if err := procs.GetJson("Processes", &processes); err != nil {
		return err
	}
	for _, proc := range processes {
		fmt.Fprintln(w, strings.Join(proc, "\t"))
	}
	w.Flush()
	return nil
}

func (cli *DockerCli) CmdPort(args ...string) error {
	cmd := cli.Subcmd("port", "CONTAINER [PRIVATE_PORT[/PROTO]]", "List port mappings for the CONTAINER, or lookup the public-facing port that is NAT-ed to the PRIVATE_PORT")
	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() < 1 {
		cmd.Usage()
		return nil
	}

	stream, _, err := cli.call("GET", "/containers/"+cmd.Arg(0)+"/json", nil, false)
	if err != nil {
		return err
	}

	env := engine.Env{}
	if err := env.Decode(stream); err != nil {
		return err
	}
	ports := nat.PortMap{}
	if err := env.GetSubEnv("NetworkSettings").GetJson("Ports", &ports); err != nil {
		return err
	}

	if cmd.NArg() == 2 {
		var (
			port  = cmd.Arg(1)
			proto = "tcp"
			parts = strings.SplitN(port, "/", 2)
		)

		if len(parts) == 2 && len(parts[1]) != 0 {
			port = parts[0]
			proto = parts[1]
		}
		natPort := port + "/" + proto
		if frontends, exists := ports[nat.Port(port+"/"+proto)]; exists && frontends != nil {
			for _, frontend := range frontends {
				fmt.Fprintf(cli.out, "%s:%s\n", frontend.HostIp, frontend.HostPort)
			}
			return nil
		}
		return fmt.Errorf("Error: No public port '%s' published for %s", natPort, cmd.Arg(0))
	}

	for from, frontends := range ports {
		for _, frontend := range frontends {
			fmt.Fprintf(cli.out, "%s -> %s:%s\n", from, frontend.HostIp, frontend.HostPort)
		}
	}

	return nil
}

// 'docker rmi IMAGE' removes all images with the name IMAGE
func (cli *DockerCli) CmdRmi(args ...string) error {
	var (
		cmd     = cli.Subcmd("rmi", "IMAGE [IMAGE...]", "Remove one or more images")
		force   = cmd.Bool([]string{"f", "-force"}, false, "Force removal of the image")
		noprune = cmd.Bool([]string{"-no-prune"}, false, "Do not delete untagged parents")
	)
	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() < 1 {
		cmd.Usage()
		return nil
	}

	v := url.Values{}
	if *force {
		v.Set("force", "1")
	}
	if *noprune {
		v.Set("noprune", "1")
	}

	var encounteredError error
	for _, name := range cmd.Args() {
		body, _, err := readBody(cli.call("DELETE", "/images/"+name+"?"+v.Encode(), nil, false))
		if err != nil {
			fmt.Fprintf(cli.err, "%s\n", err)
			encounteredError = fmt.Errorf("Error: failed to remove one or more images")
		} else {
			outs := engine.NewTable("Created", 0)
			if _, err := outs.ReadListFrom(body); err != nil {
				fmt.Fprintf(cli.err, "%s\n", err)
				encounteredError = fmt.Errorf("Error: failed to remove one or more images")
				continue
			}
			for _, out := range outs.Data {
				if out.Get("Deleted") != "" {
					fmt.Fprintf(cli.out, "Deleted: %s\n", out.Get("Deleted"))
				} else {
					fmt.Fprintf(cli.out, "Untagged: %s\n", out.Get("Untagged"))
				}
			}
		}
	}
	return encounteredError
}

func (cli *DockerCli) CmdHistory(args ...string) error {
	cmd := cli.Subcmd("history", "IMAGE", "Show the history of an image")
	quiet := cmd.Bool([]string{"q", "-quiet"}, false, "Only show numeric IDs")
	noTrunc := cmd.Bool([]string{"#notrunc", "-no-trunc"}, false, "Don't truncate output")

	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() != 1 {
		cmd.Usage()
		return nil
	}

	body, _, err := readBody(cli.call("GET", "/images/"+cmd.Arg(0)+"/history", nil, false))
	if err != nil {
		return err
	}

	outs := engine.NewTable("Created", 0)
	if _, err := outs.ReadListFrom(body); err != nil {
		return err
	}

	w := tabwriter.NewWriter(cli.out, 20, 1, 3, ' ', 0)
	if !*quiet {
		fmt.Fprintln(w, "IMAGE\tCREATED\tCREATED BY\tSIZE")
	}

	for _, out := range outs.Data {
		outID := out.Get("Id")
		if !*quiet {
			if *noTrunc {
				fmt.Fprintf(w, "%s\t", outID)
			} else {
				fmt.Fprintf(w, "%s\t", utils.TruncateID(outID))
			}

			fmt.Fprintf(w, "%s ago\t", units.HumanDuration(time.Now().UTC().Sub(time.Unix(out.GetInt64("Created"), 0))))

			if *noTrunc {
				fmt.Fprintf(w, "%s\t", out.Get("CreatedBy"))
			} else {
				fmt.Fprintf(w, "%s\t", utils.Trunc(out.Get("CreatedBy"), 45))
			}
			fmt.Fprintf(w, "%s\n", units.HumanSize(float64(out.GetInt64("Size"))))
		} else {
			if *noTrunc {
				fmt.Fprintln(w, outID)
			} else {
				fmt.Fprintln(w, utils.TruncateID(outID))
			}
		}
	}
	w.Flush()
	return nil
}

func (cli *DockerCli) CmdRm(args ...string) error {
	cmd := cli.Subcmd("rm", "CONTAINER [CONTAINER...]", "Remove one or more containers")
	v := cmd.Bool([]string{"v", "-volumes"}, false, "Remove the volumes associated with the container")
	link := cmd.Bool([]string{"l", "#link", "-link"}, false, "Remove the specified link and not the underlying container")
	force := cmd.Bool([]string{"f", "-force"}, false, "Force the removal of a running container (uses SIGKILL)")

	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() < 1 {
		cmd.Usage()
		return nil
	}

	val := url.Values{}
	if *v {
		val.Set("v", "1")
	}
	if *link {
		val.Set("link", "1")
	}

	if *force {
		val.Set("force", "1")
	}

	var encounteredError error
	for _, name := range cmd.Args() {
		_, _, err := readBody(cli.call("DELETE", "/containers/"+name+"?"+val.Encode(), nil, false))
		if err != nil {
			fmt.Fprintf(cli.err, "%s\n", err)
			encounteredError = fmt.Errorf("Error: failed to remove one or more containers")
		} else {
			fmt.Fprintf(cli.out, "%s\n", name)
		}
	}
	return encounteredError
}

// 'docker kill NAME' kills a running container
func (cli *DockerCli) CmdKill(args ...string) error {
	cmd := cli.Subcmd("kill", "CONTAINER [CONTAINER...]", "Kill a running container using SIGKILL or a specified signal")
	signal := cmd.String([]string{"s", "-signal"}, "KILL", "Signal to send to the container")

	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() < 1 {
		cmd.Usage()
		return nil
	}

	var encounteredError error
	for _, name := range cmd.Args() {
		if _, _, err := readBody(cli.call("POST", fmt.Sprintf("/containers/%s/kill?signal=%s", name, *signal), nil, false)); err != nil {
			fmt.Fprintf(cli.err, "%s\n", err)
			encounteredError = fmt.Errorf("Error: failed to kill one or more containers")
		} else {
			fmt.Fprintf(cli.out, "%s\n", name)
		}
	}
	return encounteredError
}

func (cli *DockerCli) CmdImport(args ...string) error {
	cmd := cli.Subcmd("import", "URL|- [REPOSITORY[:TAG]]", "Create an empty filesystem image and import the contents of the tarball (.tar, .tar.gz, .tgz, .bzip, .tar.xz, .txz) into it, then optionally tag it.")

	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() < 1 {
		cmd.Usage()
		return nil
	}

	var (
		v          = url.Values{}
		src        = cmd.Arg(0)
		repository = cmd.Arg(1)
	)

	v.Set("fromSrc", src)
	v.Set("repo", repository)

	if cmd.NArg() == 3 {
		fmt.Fprintf(cli.err, "[DEPRECATED] The format 'URL|- [REPOSITORY [TAG]]' as been deprecated. Please use URL|- [REPOSITORY[:TAG]]\n")
		v.Set("tag", cmd.Arg(2))
	}

	if repository != "" {
		//Check if the given image name can be resolved
		repo, _ := parsers.ParseRepositoryTag(repository)
		if _, _, err := registry.ResolveRepositoryName(repo); err != nil {
			return err
		}
	}

	var in io.Reader

	if src == "-" {
		in = cli.in
	}

	return cli.stream("POST", "/images/create?"+v.Encode(), in, cli.out, nil)
}

func (cli *DockerCli) CmdPush(args ...string) error {
	cmd := cli.Subcmd("push", "NAME[:TAG]", "Push an image or a repository to the registry")
	if err := cmd.Parse(args); err != nil {
		return nil
	}
	name := cmd.Arg(0)

	if name == "" {
		cmd.Usage()
		return nil
	}

	cli.LoadConfigFile()

	remote, tag := parsers.ParseRepositoryTag(name)

	// Resolve the Repository name from fqn to hostname + name
	hostname, _, err := registry.ResolveRepositoryName(remote)
	if err != nil {
		return err
	}
	// Resolve the Auth config relevant for this server
	authConfig := cli.configFile.ResolveAuthConfig(hostname)
	// If we're not using a custom registry, we know the restrictions
	// applied to repository names and can warn the user in advance.
	// Custom repositories can have different rules, and we must also
	// allow pushing by image ID.
	if len(strings.SplitN(name, "/", 2)) == 1 {
		username := cli.configFile.Configs[registry.IndexServerAddress()].Username
		if username == "" {
			username = "<user>"
		}
		return fmt.Errorf("You cannot push a \"root\" repository. Please rename your repository in <user>/<repo> (ex: %s/%s)", username, name)
	}

	v := url.Values{}
	v.Set("tag", tag)
	push := func(authConfig registry.AuthConfig) error {
		buf, err := json.Marshal(authConfig)
		if err != nil {
			return err
		}
		registryAuthHeader := []string{
			base64.URLEncoding.EncodeToString(buf),
		}

		return cli.stream("POST", "/images/"+remote+"/push?"+v.Encode(), nil, cli.out, map[string][]string{
			"X-Registry-Auth": registryAuthHeader,
		})
	}

	if err := push(authConfig); err != nil {
		if strings.Contains(err.Error(), "Status 401") {
			fmt.Fprintln(cli.out, "\nPlease login prior to push:")
			if err := cli.CmdLogin(hostname); err != nil {
				return err
			}
			authConfig := cli.configFile.ResolveAuthConfig(hostname)
			return push(authConfig)
		}
		return err
	}
	return nil
}

func (cli *DockerCli) CmdPull(args ...string) error {
	cmd := cli.Subcmd("pull", "NAME[:TAG]", "Pull an image or a repository from the registry")
	allTags := cmd.Bool([]string{"a", "-all-tags"}, false, "Download all tagged images in the repository")
	if err := cmd.Parse(args); err != nil {
		return nil
	}

	if cmd.NArg() != 1 {
		cmd.Usage()
		return nil
	}
	var (
		v         = url.Values{}
		remote    = cmd.Arg(0)
		newRemote = remote
	)
	taglessRemote, tag := parsers.ParseRepositoryTag(remote)
	if tag == "" && !*allTags {
		newRemote = taglessRemote + ":" + graph.DEFAULTTAG
	}
	if tag != "" && *allTags {
		return fmt.Errorf("tag can't be used with --all-tags/-a")
	}

	v.Set("fromImage", newRemote)

	// Resolve the Repository name from fqn to hostname + name
	hostname, _, err := registry.ResolveRepositoryName(taglessRemote)
	if err != nil {
		return err
	}

	cli.LoadConfigFile()

	// Resolve the Auth config relevant for this server
	authConfig := cli.configFile.ResolveAuthConfig(hostname)

	pull := func(authConfig registry.AuthConfig) error {
		buf, err := json.Marshal(authConfig)
		if err != nil {
			return err
		}
		registryAuthHeader := []string{
			base64.URLEncoding.EncodeToString(buf),
		}

		return cli.stream("POST", "/images/create?"+v.Encode(), nil, cli.out, map[string][]string{
			"X-Registry-Auth": registryAuthHeader,
		})
	}

	if err := pull(authConfig); err != nil {
		if strings.Contains(err.Error(), "Status 401") {
			fmt.Fprintln(cli.out, "\nPlease login prior to pull:")
			if err := cli.CmdLogin(hostname); err != nil {
				return err
			}
			authConfig := cli.configFile.ResolveAuthConfig(hostname)
			return pull(authConfig)
		}
		return err
	}

	return nil
}

func (cli *DockerCli) CmdImages(args ...string) error {
	cmd := cli.Subcmd("images", "[REPOSITORY]", "List images")
	quiet := cmd.Bool([]string{"q", "-quiet"}, false, "Only show numeric IDs")
	all := cmd.Bool([]string{"a", "-all"}, false, "Show all images (by default filter out the intermediate image layers)")
	noTrunc := cmd.Bool([]string{"#notrunc", "-no-trunc"}, false, "Don't truncate output")
	// FIXME: --viz and --tree are deprecated. Remove them in a future version.
	flViz := cmd.Bool([]string{"#v", "#viz", "#-viz"}, false, "Output graph in graphviz format")
	flTree := cmd.Bool([]string{"#t", "#tree", "#-tree"}, false, "Output graph in tree format")

	flFilter := opts.NewListOpts(nil)
	cmd.Var(&flFilter, []string{"f", "-filter"}, "Provide filter values (i.e. 'dangling=true')")

	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() > 1 {
		cmd.Usage()
		return nil
	}

	// Consolidate all filter flags, and sanity check them early.
	// They'll get process in the daemon/server.
	imageFilterArgs := filters.Args{}
	for _, f := range flFilter.GetAll() {
		var err error
		imageFilterArgs, err = filters.ParseFlag(f, imageFilterArgs)
		if err != nil {
			return err
		}
	}

	for name := range imageFilterArgs {
		if _, ok := acceptedImageFilterTags[name]; !ok {
			return fmt.Errorf("Invalid filter '%s'", name)
		}
	}

	matchName := cmd.Arg(0)
	// FIXME: --viz and --tree are deprecated. Remove them in a future version.
	if *flViz || *flTree {
		v := url.Values{
			"all": []string{"1"},
		}
		if len(imageFilterArgs) > 0 {
			filterJson, err := filters.ToParam(imageFilterArgs)
			if err != nil {
				return err
			}
			v.Set("filters", filterJson)
		}

		body, _, err := readBody(cli.call("GET", "/images/json?"+v.Encode(), nil, false))
		if err != nil {
			return err
		}

		outs := engine.NewTable("Created", 0)
		if _, err := outs.ReadListFrom(body); err != nil {
			return err
		}

		var (
			printNode  func(cli *DockerCli, noTrunc bool, image *engine.Env, prefix string)
			startImage *engine.Env

			roots    = engine.NewTable("Created", outs.Len())
			byParent = make(map[string]*engine.Table)
		)

		for _, image := range outs.Data {
			if image.Get("ParentId") == "" {
				roots.Add(image)
			} else {
				if children, exists := byParent[image.Get("ParentId")]; exists {
					children.Add(image)
				} else {
					byParent[image.Get("ParentId")] = engine.NewTable("Created", 1)
					byParent[image.Get("ParentId")].Add(image)
				}
			}

			if matchName != "" {
				if matchName == image.Get("Id") || matchName == utils.TruncateID(image.Get("Id")) {
					startImage = image
				}

				for _, repotag := range image.GetList("RepoTags") {
					if repotag == matchName {
						startImage = image
					}
				}
			}
		}

		if *flViz {
			fmt.Fprintf(cli.out, "digraph docker {\n")
			printNode = (*DockerCli).printVizNode
		} else {
			printNode = (*DockerCli).printTreeNode
		}

		if startImage != nil {
			root := engine.NewTable("Created", 1)
			root.Add(startImage)
			cli.WalkTree(*noTrunc, root, byParent, "", printNode)
		} else if matchName == "" {
			cli.WalkTree(*noTrunc, roots, byParent, "", printNode)
		}
		if *flViz {
			fmt.Fprintf(cli.out, " base [style=invisible]\n}\n")
		}
	} else {
		v := url.Values{}
		if len(imageFilterArgs) > 0 {
			filterJson, err := filters.ToParam(imageFilterArgs)
			if err != nil {
				return err
			}
			v.Set("filters", filterJson)
		}

		if cmd.NArg() == 1 {
			// FIXME rename this parameter, to not be confused with the filters flag
			v.Set("filter", matchName)
		}
		if *all {
			v.Set("all", "1")
		}

		body, _, err := readBody(cli.call("GET", "/images/json?"+v.Encode(), nil, false))

		if err != nil {
			return err
		}

		outs := engine.NewTable("Created", 0)
		if _, err := outs.ReadListFrom(body); err != nil {
			return err
		}

		w := tabwriter.NewWriter(cli.out, 20, 1, 3, ' ', 0)
		if !*quiet {
			fmt.Fprintln(w, "REPOSITORY\tTAG\tIMAGE ID\tCREATED\tVIRTUAL SIZE")
		}

		for _, out := range outs.Data {
			for _, repotag := range out.GetList("RepoTags") {

				repo, tag := parsers.ParseRepositoryTag(repotag)
				outID := out.Get("Id")
				if !*noTrunc {
					outID = utils.TruncateID(outID)
				}

				if !*quiet {
					fmt.Fprintf(w, "%s\t%s\t%s\t%s ago\t%s\n", repo, tag, outID, units.HumanDuration(time.Now().UTC().Sub(time.Unix(out.GetInt64("Created"), 0))), units.HumanSize(float64(out.GetInt64("VirtualSize"))))
				} else {
					fmt.Fprintln(w, outID)
				}
			}
		}

		if !*quiet {
			w.Flush()
		}
	}
	return nil
}

// FIXME: --viz and --tree are deprecated. Remove them in a future version.
func (cli *DockerCli) WalkTree(noTrunc bool, images *engine.Table, byParent map[string]*engine.Table, prefix string, printNode func(cli *DockerCli, noTrunc bool, image *engine.Env, prefix string)) {
	length := images.Len()
	if length > 1 {
		for index, image := range images.Data {
			if index+1 == length {
				printNode(cli, noTrunc, image, prefix+"└─")
				if subimages, exists := byParent[image.Get("Id")]; exists {
					cli.WalkTree(noTrunc, subimages, byParent, prefix+"  ", printNode)
				}
			} else {
				printNode(cli, noTrunc, image, prefix+"\u251C─")
				if subimages, exists := byParent[image.Get("Id")]; exists {
					cli.WalkTree(noTrunc, subimages, byParent, prefix+"\u2502 ", printNode)
				}
			}
		}
	} else {
		for _, image := range images.Data {
			printNode(cli, noTrunc, image, prefix+"└─")
			if subimages, exists := byParent[image.Get("Id")]; exists {
				cli.WalkTree(noTrunc, subimages, byParent, prefix+"  ", printNode)
			}
		}
	}
}

// FIXME: --viz and --tree are deprecated. Remove them in a future version.
func (cli *DockerCli) printVizNode(noTrunc bool, image *engine.Env, prefix string) {
	var (
		imageID  string
		parentID string
	)
	if noTrunc {
		imageID = image.Get("Id")
		parentID = image.Get("ParentId")
	} else {
		imageID = utils.TruncateID(image.Get("Id"))
		parentID = utils.TruncateID(image.Get("ParentId"))
	}
	if parentID == "" {
		fmt.Fprintf(cli.out, " base -> \"%s\" [style=invis]\n", imageID)
	} else {
		fmt.Fprintf(cli.out, " \"%s\" -> \"%s\"\n", parentID, imageID)
	}
	if image.GetList("RepoTags")[0] != "<none>:<none>" {
		fmt.Fprintf(cli.out, " \"%s\" [label=\"%s\\n%s\",shape=box,fillcolor=\"paleturquoise\",style=\"filled,rounded\"];\n",
			imageID, imageID, strings.Join(image.GetList("RepoTags"), "\\n"))
	}
}

// FIXME: --viz and --tree are deprecated. Remove them in a future version.
func (cli *DockerCli) printTreeNode(noTrunc bool, image *engine.Env, prefix string) {
	var imageID string
	if noTrunc {
		imageID = image.Get("Id")
	} else {
		imageID = utils.TruncateID(image.Get("Id"))
	}

	fmt.Fprintf(cli.out, "%s%s Virtual Size: %s", prefix, imageID, units.HumanSize(float64(image.GetInt64("VirtualSize"))))
	if image.GetList("RepoTags")[0] != "<none>:<none>" {
		fmt.Fprintf(cli.out, " Tags: %s\n", strings.Join(image.GetList("RepoTags"), ", "))
	} else {
		fmt.Fprint(cli.out, "\n")
	}
}

func (cli *DockerCli) CmdPs(args ...string) error {
	var (
		err error

		psFilterArgs = filters.Args{}
		v            = url.Values{}

		cmd      = cli.Subcmd("ps", "", "List containers")
		quiet    = cmd.Bool([]string{"q", "-quiet"}, false, "Only display numeric IDs")
		size     = cmd.Bool([]string{"s", "-size"}, false, "Display total file sizes")
		all      = cmd.Bool([]string{"a", "-all"}, false, "Show all containers. Only running containers are shown by default.")
		noTrunc  = cmd.Bool([]string{"#notrunc", "-no-trunc"}, false, "Don't truncate output")
		nLatest  = cmd.Bool([]string{"l", "-latest"}, false, "Show only the latest created container, include non-running ones.")
		since    = cmd.String([]string{"#sinceId", "#-since-id", "-since"}, "", "Show only containers created since Id or Name, include non-running ones.")
		before   = cmd.String([]string{"#beforeId", "#-before-id", "-before"}, "", "Show only container created before Id or Name, include non-running ones.")
		last     = cmd.Int([]string{"n"}, -1, "Show n last created containers, include non-running ones.")
		flFilter = opts.NewListOpts(nil)
	)

	cmd.Var(&flFilter, []string{"f", "-filter"}, "Provide filter values. Valid filters:\nexited=<int> - containers with exit code of <int>\nstatus=(restarting|running|paused|exited)")

	if err := cmd.Parse(args); err != nil {
		return nil
	}

	if *last == -1 && *nLatest {
		*last = 1
	}

	if *all {
		v.Set("all", "1")
	}

	if *last != -1 {
		v.Set("limit", strconv.Itoa(*last))
	}

	if *since != "" {
		v.Set("since", *since)
	}

	if *before != "" {
		v.Set("before", *before)
	}

	if *size {
		v.Set("size", "1")
	}

	// Consolidate all filter flags, and sanity check them.
	// They'll get processed in the daemon/server.
	for _, f := range flFilter.GetAll() {
		if psFilterArgs, err = filters.ParseFlag(f, psFilterArgs); err != nil {
			return err
		}
	}

	if len(psFilterArgs) > 0 {
		filterJson, err := filters.ToParam(psFilterArgs)
		if err != nil {
			return err
		}

		v.Set("filters", filterJson)
	}

	body, _, err := readBody(cli.call("GET", "/containers/json?"+v.Encode(), nil, false))
	if err != nil {
		return err
	}

	outs := engine.NewTable("Created", 0)
	if _, err := outs.ReadListFrom(body); err != nil {
		return err
	}

	w := tabwriter.NewWriter(cli.out, 20, 1, 3, ' ', 0)
	if !*quiet {
		fmt.Fprint(w, "CONTAINER ID\tIMAGE\tCOMMAND\tCREATED\tSTATUS\tPORTS\tNAMES")

		if *size {
			fmt.Fprintln(w, "\tSIZE")
		} else {
			fmt.Fprint(w, "\n")
		}
	}

	stripNamePrefix := func(ss []string) []string {
		for i, s := range ss {
			ss[i] = s[1:]
		}

		return ss
	}

	for _, out := range outs.Data {
		outID := out.Get("Id")

		if !*noTrunc {
			outID = utils.TruncateID(outID)
		}

		if *quiet {
			fmt.Fprintln(w, outID)

			continue
		}

		var (
			outNames   = stripNamePrefix(out.GetList("Names"))
			outCommand = strconv.Quote(out.Get("Command"))
			ports      = engine.NewTable("", 0)
		)

		if !*noTrunc {
			outCommand = utils.Trunc(outCommand, 20)

			// only display the default name for the container with notrunc is passed
			for _, name := range outNames {
				if len(strings.Split(name, "/")) == 1 {
					outNames = []string{name}

					break
				}
			}
		}

		ports.ReadListFrom([]byte(out.Get("Ports")))

		image := out.Get("Image")
		if image == "" {
			image = "<no image>"
		}

		fmt.Fprintf(w, "%s\t%s\t%s\t%s ago\t%s\t%s\t%s\t", outID, image, outCommand,
			units.HumanDuration(time.Now().UTC().Sub(time.Unix(out.GetInt64("Created"), 0))),
			out.Get("Status"), api.DisplayablePorts(ports), strings.Join(outNames, ","))

		if *size {
			if out.GetInt("SizeRootFs") > 0 {
				fmt.Fprintf(w, "%s (virtual %s)\n", units.HumanSize(float64(out.GetInt64("SizeRw"))), units.HumanSize(float64(out.GetInt64("SizeRootFs"))))
			} else {
				fmt.Fprintf(w, "%s\n", units.HumanSize(float64(out.GetInt64("SizeRw"))))
			}

			continue
		}

		fmt.Fprint(w, "\n")
	}

	if !*quiet {
		w.Flush()
	}

	return nil
}

func (cli *DockerCli) CmdCommit(args ...string) error {
	cmd := cli.Subcmd("commit", "CONTAINER [REPOSITORY[:TAG]]", "Create a new image from a container's changes")
	flPause := cmd.Bool([]string{"p", "-pause"}, true, "Pause container during commit")
	flComment := cmd.String([]string{"m", "-message"}, "", "Commit message")
	flAuthor := cmd.String([]string{"a", "#author", "-author"}, "", "Author (e.g., \"John Hannibal Smith <hannibal@a-team.com>\")")
	// FIXME: --run is deprecated, it will be replaced with inline Dockerfile commands.
	flConfig := cmd.String([]string{"#run", "#-run"}, "", "This option is deprecated and will be removed in a future version in favor of inline Dockerfile-compatible commands")
	if err := cmd.Parse(args); err != nil {
		return nil
	}

	var (
		name            = cmd.Arg(0)
		repository, tag = parsers.ParseRepositoryTag(cmd.Arg(1))
	)

	if name == "" || len(cmd.Args()) > 2 {
		cmd.Usage()
		return nil
	}

	//Check if the given image name can be resolved
	if repository != "" {
		if _, _, err := registry.ResolveRepositoryName(repository); err != nil {
			return err
		}
	}

	v := url.Values{}
	v.Set("container", name)
	v.Set("repo", repository)
	v.Set("tag", tag)
	v.Set("comment", *flComment)
	v.Set("author", *flAuthor)

	if *flPause != true {
		v.Set("pause", "0")
	}

	var (
		config *runconfig.Config
		env    engine.Env
	)
	if *flConfig != "" {
		config = &runconfig.Config{}
		if err := json.Unmarshal([]byte(*flConfig), config); err != nil {
			return err
		}
	}
	stream, _, err := cli.call("POST", "/commit?"+v.Encode(), config, false)
	if err != nil {
		return err
	}
	if err := env.Decode(stream); err != nil {
		return err
	}

	fmt.Fprintf(cli.out, "%s\n", env.Get("Id"))
	return nil
}

func (cli *DockerCli) CmdEvents(args ...string) error {
	cmd := cli.Subcmd("events", "", "Get real time events from the server")
	since := cmd.String([]string{"#since", "-since"}, "", "Show all events created since timestamp")
	until := cmd.String([]string{"-until"}, "", "Stream events until this timestamp")

	flFilter := opts.NewListOpts(nil)
	cmd.Var(&flFilter, []string{"f", "-filter"}, "Provide filter values (i.e. 'event=stop')")

	if err := cmd.Parse(args); err != nil {
		return nil
	}

	if cmd.NArg() != 0 {
		cmd.Usage()
		return nil
	}
	var (
		v               = url.Values{}
		loc             = time.FixedZone(time.Now().Zone())
		eventFilterArgs = filters.Args{}
	)

	// Consolidate all filter flags, and sanity check them early.
	// They'll get process in the daemon/server.
	for _, f := range flFilter.GetAll() {
		var err error
		eventFilterArgs, err = filters.ParseFlag(f, eventFilterArgs)
		if err != nil {
			return err
		}
	}
	var setTime = func(key, value string) {
		format := timeutils.RFC3339NanoFixed
		if len(value) < len(format) {
			format = format[:len(value)]
		}
		if t, err := time.ParseInLocation(format, value, loc); err == nil {
			v.Set(key, strconv.FormatInt(t.Unix(), 10))
		} else {
			v.Set(key, value)
		}
	}
	if *since != "" {
		setTime("since", *since)
	}
	if *until != "" {
		setTime("until", *until)
	}
	if len(eventFilterArgs) > 0 {
		filterJson, err := filters.ToParam(eventFilterArgs)
		if err != nil {
			return err
		}
		v.Set("filters", filterJson)
	}
	if err := cli.stream("GET", "/events?"+v.Encode(), nil, cli.out, nil); err != nil {
		return err
	}
	return nil
}

func (cli *DockerCli) CmdExport(args ...string) error {
	cmd := cli.Subcmd("export", "CONTAINER", "Export the contents of a filesystem as a tar archive to STDOUT")
	if err := cmd.Parse(args); err != nil {
		return nil
	}

	if cmd.NArg() != 1 {
		cmd.Usage()
		return nil
	}

	if err := cli.stream("GET", "/containers/"+cmd.Arg(0)+"/export", nil, cli.out, nil); err != nil {
		return err
	}
	return nil
}

func (cli *DockerCli) CmdDiff(args ...string) error {
	cmd := cli.Subcmd("diff", "CONTAINER", "Inspect changes on a container's filesystem")
	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() != 1 {
		cmd.Usage()
		return nil
	}

	body, _, err := readBody(cli.call("GET", "/containers/"+cmd.Arg(0)+"/changes", nil, false))

	if err != nil {
		return err
	}

	outs := engine.NewTable("", 0)
	if _, err := outs.ReadListFrom(body); err != nil {
		return err
	}
	for _, change := range outs.Data {
		var kind string
		switch change.GetInt("Kind") {
		case archive.ChangeModify:
			kind = "C"
		case archive.ChangeAdd:
			kind = "A"
		case archive.ChangeDelete:
			kind = "D"
		}
		fmt.Fprintf(cli.out, "%s %s\n", kind, change.Get("Path"))
	}
	return nil
}

func (cli *DockerCli) CmdLogs(args ...string) error {
	var (
		cmd    = cli.Subcmd("logs", "CONTAINER", "Fetch the logs of a container")
		follow = cmd.Bool([]string{"f", "-follow"}, false, "Follow log output")
		times  = cmd.Bool([]string{"t", "-timestamps"}, false, "Show timestamps")
		tail   = cmd.String([]string{"-tail"}, "all", "Output the specified number of lines at the end of logs (defaults to all logs)")
	)

	if err := cmd.Parse(args); err != nil {
		return nil
	}

	if cmd.NArg() != 1 {
		cmd.Usage()
		return nil
	}
	name := cmd.Arg(0)

	stream, _, err := cli.call("GET", "/containers/"+name+"/json", nil, false)
	if err != nil {
		return err
	}

	env := engine.Env{}
	if err := env.Decode(stream); err != nil {
		return err
	}

	v := url.Values{}
	v.Set("stdout", "1")
	v.Set("stderr", "1")

	if *times {
		v.Set("timestamps", "1")
	}

	if *follow {
		v.Set("follow", "1")
	}
	v.Set("tail", *tail)

	return cli.streamHelper("GET", "/containers/"+name+"/logs?"+v.Encode(), env.GetSubEnv("Config").GetBool("Tty"), nil, cli.out, cli.err, nil)
}

func (cli *DockerCli) CmdAttach(args ...string) error {
	var (
		cmd     = cli.Subcmd("attach", "CONTAINER", "Attach to a running container")
		noStdin = cmd.Bool([]string{"#nostdin", "-no-stdin"}, false, "Do not attach STDIN")
		proxy   = cmd.Bool([]string{"#sig-proxy", "-sig-proxy"}, true, "Proxy all received signals to the process (non-TTY mode only). SIGCHLD, SIGKILL, and SIGSTOP are not proxied.")
	)

	if err := cmd.Parse(args); err != nil {
		return nil
	}

	if cmd.NArg() != 1 {
		cmd.Usage()
		return nil
	}
	name := cmd.Arg(0)

	stream, _, err := cli.call("GET", "/containers/"+name+"/json", nil, false)
	if err != nil {
		return err
	}

	env := engine.Env{}
	if err := env.Decode(stream); err != nil {
		return err
	}

	if !env.GetSubEnv("State").GetBool("Running") {
		return fmt.Errorf("You cannot attach to a stopped container, start it first")
	}

	var (
		config = env.GetSubEnv("Config")
		tty    = config.GetBool("Tty")
	)

	if err := cli.CheckTtyInput(!*noStdin, tty); err != nil {
		return err
	}

	if tty && cli.isTerminalOut {
		if err := cli.monitorTtySize(cmd.Arg(0), false); err != nil {
			log.Debugf("Error monitoring TTY size: %s", err)
		}
	}

	var in io.ReadCloser

	v := url.Values{}
	v.Set("stream", "1")
	if !*noStdin && config.GetBool("OpenStdin") {
		v.Set("stdin", "1")
		in = cli.in
	}

	v.Set("stdout", "1")
	v.Set("stderr", "1")

	if *proxy && !tty {
		sigc := cli.forwardAllSignals(cmd.Arg(0))
		defer signal.StopCatch(sigc)
	}

	if err := cli.hijack("POST", "/containers/"+cmd.Arg(0)+"/attach?"+v.Encode(), tty, in, cli.out, cli.err, nil, nil); err != nil {
		return err
	}

	_, status, err := getExitCode(cli, cmd.Arg(0))
	if err != nil {
		return err
	}
	if status != 0 {
		return &utils.StatusError{StatusCode: status}
	}

	return nil
}

func (cli *DockerCli) CmdSearch(args ...string) error {
	cmd := cli.Subcmd("search", "TERM", "Search the Docker Hub for images")
	noTrunc := cmd.Bool([]string{"#notrunc", "-no-trunc"}, false, "Don't truncate output")
	trusted := cmd.Bool([]string{"#t", "#trusted", "#-trusted"}, false, "Only show trusted builds")
	automated := cmd.Bool([]string{"-automated"}, false, "Only show automated builds")
	stars := cmd.Int([]string{"s", "#stars", "-stars"}, 0, "Only displays with at least x stars")
	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() != 1 {
		cmd.Usage()
		return nil
	}

	v := url.Values{}
	v.Set("term", cmd.Arg(0))

	body, _, err := readBody(cli.call("GET", "/images/search?"+v.Encode(), nil, true))

	if err != nil {
		return err
	}
	outs := engine.NewTable("star_count", 0)
	if _, err := outs.ReadListFrom(body); err != nil {
		return err
	}
	w := tabwriter.NewWriter(cli.out, 10, 1, 3, ' ', 0)
	fmt.Fprintf(w, "NAME\tDESCRIPTION\tSTARS\tOFFICIAL\tAUTOMATED\n")
	for _, out := range outs.Data {
		if ((*automated || *trusted) && (!out.GetBool("is_trusted") && !out.GetBool("is_automated"))) || (*stars > out.GetInt("star_count")) {
			continue
		}
		desc := strings.Replace(out.Get("description"), "\n", " ", -1)
		desc = strings.Replace(desc, "\r", " ", -1)
		if !*noTrunc && len(desc) > 45 {
			desc = utils.Trunc(desc, 42) + "..."
		}
		fmt.Fprintf(w, "%s\t%s\t%d\t", out.Get("name"), desc, out.GetInt("star_count"))
		if out.GetBool("is_official") {
			fmt.Fprint(w, "[OK]")

		}
		fmt.Fprint(w, "\t")
		if out.GetBool("is_automated") || out.GetBool("is_trusted") {
			fmt.Fprint(w, "[OK]")
		}
		fmt.Fprint(w, "\n")
	}
	w.Flush()
	return nil
}

// Ports type - Used to parse multiple -p flags
type ports []int

func (cli *DockerCli) CmdTag(args ...string) error {
	cmd := cli.Subcmd("tag", "IMAGE[:TAG] [REGISTRYHOST/][USERNAME/]NAME[:TAG]", "Tag an image into a repository")
	force := cmd.Bool([]string{"f", "#force", "-force"}, false, "Force")
	if err := cmd.Parse(args); err != nil {
		return nil
	}
	if cmd.NArg() != 2 {
		cmd.Usage()
		return nil
	}

	var (
		repository, tag = parsers.ParseRepositoryTag(cmd.Arg(1))
		v               = url.Values{}
	)

	//Check if the given image name can be resolved
	if _, _, err := registry.ResolveRepositoryName(repository); err != nil {
		return err
	}
	v.Set("repo", repository)
	v.Set("tag", tag)

	if *force {
		v.Set("force", "1")
	}

	if _, _, err := readBody(cli.call("POST", "/images/"+cmd.Arg(0)+"/tag?"+v.Encode(), nil, false)); err != nil {
		return err
	}
	return nil
}

func (cli *DockerCli) pullImage(image string) error {
	return cli.pullImageCustomOut(image, cli.out)
}

func (cli *DockerCli) pullImageCustomOut(image string, out io.Writer) error {
	v := url.Values{}
	repos, tag := parsers.ParseRepositoryTag(image)
	// pull only the image tagged 'latest' if no tag was specified
	if tag == "" {
		tag = graph.DEFAULTTAG
	}
	v.Set("fromImage", repos)
	v.Set("tag", tag)

	// Resolve the Repository name from fqn to hostname + name
	hostname, _, err := registry.ResolveRepositoryName(repos)
	if err != nil {
		return err
	}

	// Load the auth config file, to be able to pull the image
	cli.LoadConfigFile()

	// Resolve the Auth config relevant for this server
	authConfig := cli.configFile.ResolveAuthConfig(hostname)
	buf, err := json.Marshal(authConfig)
	if err != nil {
		return err
	}

	registryAuthHeader := []string{
		base64.URLEncoding.EncodeToString(buf),
	}
	if err = cli.stream("POST", "/images/create?"+v.Encode(), nil, out, map[string][]string{"X-Registry-Auth": registryAuthHeader}); err != nil {
		return err
	}
	return nil
}

type cidFile struct {
	path    string
	file    *os.File
	written bool
}

func newCIDFile(path string) (*cidFile, error) {
	if _, err := os.Stat(path); err == nil {
		return nil, fmt.Errorf("Container ID file found, make sure the other container isn't running or delete %s", path)
	}
	f, err := os.Create(path)
	if err != nil {
		return nil, fmt.Errorf("Failed to create the container ID file: %s", err)
	}

	return &cidFile{path: path, file: f}, nil
}

func (cid *cidFile) Close() error {
	cid.file.Close()

	if !cid.written {
		if err := os.Remove(cid.path); err != nil {
			return fmt.Errorf("failed to remove the CID file '%s': %s \n", cid.path, err)
		}
	}

	return nil
}

func (cid *cidFile) Write(id string) error {
	if _, err := cid.file.Write([]byte(id)); err != nil {
		return fmt.Errorf("Failed to write the container ID to the file: %s", err)
	}
	cid.written = true
	return nil
}

func (cli *DockerCli) createContainer(config *runconfig.Config, hostConfig *runconfig.HostConfig, cidfile, name string) (engine.Env, error) {
	containerValues := url.Values{}
	if name != "" {
		containerValues.Set("name", name)
	}

	mergedConfig := runconfig.MergeConfigs(config, hostConfig)

	var containerIDFile *cidFile
	if cidfile != "" {
		var err error
		if containerIDFile, err = newCIDFile(cidfile); err != nil {
			return nil, err
		}
		defer containerIDFile.Close()
	}

	//create the container
	stream, statusCode, err := cli.call("POST", "/containers/create?"+containerValues.Encode(), mergedConfig, false)
	//if image not found try to pull it
	if statusCode == 404 {
		repo, tag := parsers.ParseRepositoryTag(config.Image)
		if tag == "" {
			tag = graph.DEFAULTTAG
		}
		fmt.Fprintf(cli.err, "Unable to find image '%s:%s' locally\n", repo, tag)

		// we don't want to write to stdout anything apart from container.ID
		if err = cli.pullImageCustomOut(config.Image, cli.err); err != nil {
			return nil, err
		}
		// Retry
		if stream, _, err = cli.call("POST", "/containers/create?"+containerValues.Encode(), mergedConfig, false); err != nil {
			return nil, err
		}
	} else if err != nil {
		return nil, err
	}

	var result engine.Env
	if err := result.Decode(stream); err != nil {
		return nil, err
	}

	for _, warning := range result.GetList("Warnings") {
		fmt.Fprintf(cli.err, "WARNING: %s\n", warning)
	}

	if containerIDFile != nil {
		if err = containerIDFile.Write(result.Get("Id")); err != nil {
			return nil, err
		}
	}

	return result, nil

}

func (cli *DockerCli) CmdCreate(args ...string) error {
	cmd := cli.Subcmd("create", "IMAGE [COMMAND] [ARG...]", "Create a new container")

	// These are flags not stored in Config/HostConfig
	var (
		flName = cmd.String([]string{"-name"}, "", "Assign a name to the container")
	)

	config, hostConfig, cmd, err := runconfig.Parse(cmd, args)
	if err != nil {
		return err
	}
	if config.Image == "" {
		cmd.Usage()
		return nil
	}

	createResult, err := cli.createContainer(config, hostConfig, hostConfig.ContainerIDFile, *flName)
	if err != nil {
		return err
	}

	fmt.Fprintf(cli.out, "%s\n", createResult.Get("Id"))

	return nil
}

func (cli *DockerCli) CmdRun(args ...string) error {
	// FIXME: just use runconfig.Parse already
	cmd := cli.Subcmd("run", "IMAGE [COMMAND] [ARG...]", "Run a command in a new container")

	// These are flags not stored in Config/HostConfig
	var (
		flAutoRemove = cmd.Bool([]string{"#rm", "-rm"}, false, "Automatically remove the container when it exits (incompatible with -d)")
		flDetach     = cmd.Bool([]string{"d", "-detach"}, false, "Detached mode: run the container in the background and print the new container ID")
		flSigProxy   = cmd.Bool([]string{"#sig-proxy", "-sig-proxy"}, true, "Proxy received signals to the process (non-TTY mode only). SIGCHLD, SIGSTOP, and SIGKILL are not proxied.")
		flName       = cmd.String([]string{"#name", "-name"}, "", "Assign a name to the container")
		flAttach     *opts.ListOpts

		ErrConflictAttachDetach               = fmt.Errorf("Conflicting options: -a and -d")
		ErrConflictRestartPolicyAndAutoRemove = fmt.Errorf("Conflicting options: --restart and --rm")
		ErrConflictDetachAutoRemove           = fmt.Errorf("Conflicting options: --rm and -d")
	)

	config, hostConfig, cmd, err := runconfig.Parse(cmd, args)
	if err != nil {
		return err
	}
	if config.Image == "" {
		cmd.Usage()
		return nil
	}

	if !*flDetach {
		if err := cli.CheckTtyInput(config.AttachStdin, config.Tty); err != nil {
			return err
		}
	} else {
		if fl := cmd.Lookup("attach"); fl != nil {
			flAttach = fl.Value.(*opts.ListOpts)
			if flAttach.Len() != 0 {
				return ErrConflictAttachDetach
			}
		}
		if *flAutoRemove {
			return ErrConflictDetachAutoRemove
		}

		config.AttachStdin = false
		config.AttachStdout = false
		config.AttachStderr = false
		config.StdinOnce = false
	}

	// Disable flSigProxy when in TTY mode
	sigProxy := *flSigProxy
	if config.Tty {
		sigProxy = false
	}

	runResult, err := cli.createContainer(config, hostConfig, hostConfig.ContainerIDFile, *flName)
	if err != nil {
		return err
	}

	if sigProxy {
		sigc := cli.forwardAllSignals(runResult.Get("Id"))
		defer signal.StopCatch(sigc)
	}

	var (
		waitDisplayId chan struct{}
		errCh         chan error
	)

	if !config.AttachStdout && !config.AttachStderr {
		// Make this asynchronous to allow the client to write to stdin before having to read the ID
		waitDisplayId = make(chan struct{})
		go func() {
			defer close(waitDisplayId)
			fmt.Fprintf(cli.out, "%s\n", runResult.Get("Id"))
		}()
	}

	if *flAutoRemove && (hostConfig.RestartPolicy.Name == "always" || hostConfig.RestartPolicy.Name == "on-failure") {
		return ErrConflictRestartPolicyAndAutoRemove
	}

	// We need to instantiate the chan because the select needs it. It can
	// be closed but can't be uninitialized.
	hijacked := make(chan io.Closer)

	// Block the return until the chan gets closed
	defer func() {
		log.Debugf("End of CmdRun(), Waiting for hijack to finish.")
		if _, ok := <-hijacked; ok {
			log.Errorf("Hijack did not finish (chan still open)")
		}
	}()

	if config.AttachStdin || config.AttachStdout || config.AttachStderr {
		var (
			out, stderr io.Writer
			in          io.ReadCloser
			v           = url.Values{}
		)
		v.Set("stream", "1")

		if config.AttachStdin {
			v.Set("stdin", "1")
			in = cli.in
		}
		if config.AttachStdout {
			v.Set("stdout", "1")
			out = cli.out
		}
		if config.AttachStderr {
			v.Set("stderr", "1")
			if config.Tty {
				stderr = cli.out
			} else {
				stderr = cli.err
			}
		}

		errCh = promise.Go(func() error {
			return cli.hijack("POST", "/containers/"+runResult.Get("Id")+"/attach?"+v.Encode(), config.Tty, in, out, stderr, hijacked, nil)
		})
	} else {
		close(hijacked)
	}

	// Acknowledge the hijack before starting
	select {
	case closer := <-hijacked:
		// Make sure that the hijack gets closed when returning (results
		// in closing the hijack chan and freeing server's goroutines)
		if closer != nil {
			defer closer.Close()
		}
	case err := <-errCh:
		if err != nil {
			log.Debugf("Error hijack: %s", err)
			return err
		}
	}

	//start the container
	if _, _, err = readBody(cli.call("POST", "/containers/"+runResult.Get("Id")+"/start", nil, false)); err != nil {
		return err
	}

	if (config.AttachStdin || config.AttachStdout || config.AttachStderr) && config.Tty && cli.isTerminalOut {
		if err := cli.monitorTtySize(runResult.Get("Id"), false); err != nil {
			log.Errorf("Error monitoring TTY size: %s", err)
		}
	}

	if errCh != nil {
		if err := <-errCh; err != nil {
			log.Debugf("Error hijack: %s", err)
			return err
		}
	}

	// Detached mode: wait for the id to be displayed and return.
	if !config.AttachStdout && !config.AttachStderr {
		// Detached mode
		<-waitDisplayId
		return nil
	}

	var status int

	// Attached mode
	if *flAutoRemove {
		// Autoremove: wait for the container to finish, retrieve
		// the exit code and remove the container
		if _, _, err := readBody(cli.call("POST", "/containers/"+runResult.Get("Id")+"/wait", nil, false)); err != nil {
			return err
		}
		if _, status, err = getExitCode(cli, runResult.Get("Id")); err != nil {
			return err
		}
		if _, _, err := readBody(cli.call("DELETE", "/containers/"+runResult.Get("Id")+"?v=1", nil, false)); err != nil {
			return err
		}
	} else {
		// No Autoremove: Simply retrieve the exit code
		if !config.Tty {
			// In non-TTY mode, we can't detach, so we must wait for container exit
			if status, err = waitForExit(cli, runResult.Get("Id")); err != nil {
				return err
			}
		} else {
			// In TTY mode, there is a race: if the process dies too slowly, the state could
			// be updated after the getExitCode call and result in the wrong exit code being reported
			if _, status, err = getExitCode(cli, runResult.Get("Id")); err != nil {
				return err
			}
		}
	}
	if status != 0 {
		return &utils.StatusError{StatusCode: status}
	}
	return nil
}

func (cli *DockerCli) CmdCp(args ...string) error {
	cmd := cli.Subcmd("cp", "CONTAINER:PATH HOSTPATH", "Copy files/folders from the PATH to the HOSTPATH")
	if err := cmd.Parse(args); err != nil {
		return nil
	}

	if cmd.NArg() != 2 {
		cmd.Usage()
		return nil
	}

	var copyData engine.Env
	info := strings.Split(cmd.Arg(0), ":")

	if len(info) != 2 {
		return fmt.Errorf("Error: Path not specified")
	}

	copyData.Set("Resource", info[1])
	copyData.Set("HostPath", cmd.Arg(1))

	stream, statusCode, err := cli.call("POST", "/containers/"+info[0]+"/copy", copyData, false)
	if stream != nil {
		defer stream.Close()
	}
	if statusCode == 404 {
		return fmt.Errorf("No such container: %v", info[0])
	}
	if err != nil {
		return err
	}

	if statusCode == 200 {
		if err := archive.Untar(stream, copyData.Get("HostPath"), &archive.TarOptions{NoLchown: true}); err != nil {
			return err
		}
	}
	return nil
}

func (cli *DockerCli) CmdSave(args ...string) error {
	cmd := cli.Subcmd("save", "IMAGE [IMAGE...]", "Save an image(s) to a tar archive (streamed to STDOUT by default)")
	outfile := cmd.String([]string{"o", "-output"}, "", "Write to a file, instead of STDOUT")

	if err := cmd.Parse(args); err != nil {
		return err
	}

	if cmd.NArg() < 1 {
		cmd.Usage()
		return nil
	}

	var (
		output io.Writer = cli.out
		err    error
	)
	if *outfile != "" {
		output, err = os.Create(*outfile)
		if err != nil {
			return err
		}
	} else if cli.isTerminalOut {
		return errors.New("Cowardly refusing to save to a terminal. Use the -o flag or redirect.")
	}

	if len(cmd.Args()) == 1 {
		image := cmd.Arg(0)
		if err := cli.stream("GET", "/images/"+image+"/get", nil, output, nil); err != nil {
			return err
		}
	} else {
		v := url.Values{}
		for _, arg := range cmd.Args() {
			v.Add("names", arg)
		}
		if err := cli.stream("GET", "/images/get?"+v.Encode(), nil, output, nil); err != nil {
			return err
		}
	}
	return nil
}

func (cli *DockerCli) CmdLoad(args ...string) error {
	cmd := cli.Subcmd("load", "", "Load an image from a tar archive on STDIN")
	infile := cmd.String([]string{"i", "-input"}, "", "Read from a tar archive file, instead of STDIN")

	if err := cmd.Parse(args); err != nil {
		return err
	}

	if cmd.NArg() != 0 {
		cmd.Usage()
		return nil
	}

	var (
		input io.Reader = cli.in
		err   error
	)
	if *infile != "" {
		input, err = os.Open(*infile)
		if err != nil {
			return err
		}
	}
	if err := cli.stream("POST", "/images/load", input, cli.out, nil); err != nil {
		return err
	}
	return nil
}

func (cli *DockerCli) CmdExec(args ...string) error {
	cmd := cli.Subcmd("exec", "CONTAINER COMMAND [ARG...]", "Run a command in a running container")

	execConfig, err := runconfig.ParseExec(cmd, args)
	if err != nil {
		return err
	}
	if execConfig.Container == "" {
		cmd.Usage()
		return nil
	}

	stream, _, err := cli.call("POST", "/containers/"+execConfig.Container+"/exec", execConfig, false)
	if err != nil {
		return err
	}

	var execResult engine.Env
	if err := execResult.Decode(stream); err != nil {
		return err
	}

	execID := execResult.Get("Id")

	if execID == "" {
		fmt.Fprintf(cli.out, "exec ID empty")
		return nil
	}

	if !execConfig.Detach {
		if err := cli.CheckTtyInput(execConfig.AttachStdin, execConfig.Tty); err != nil {
			return err
		}
	} else {
		if _, _, err := readBody(cli.call("POST", "/exec/"+execID+"/start", execConfig, false)); err != nil {
			return err
		}
		// For now don't print this - wait for when we support exec wait()
		// fmt.Fprintf(cli.out, "%s\n", execID)
		return nil
	}

	// Interactive exec requested.
	var (
		out, stderr io.Writer
		in          io.ReadCloser
		hijacked    = make(chan io.Closer)
		errCh       chan error
	)

	// Block the return until the chan gets closed
	defer func() {
		log.Debugf("End of CmdExec(), Waiting for hijack to finish.")
		if _, ok := <-hijacked; ok {
			log.Errorf("Hijack did not finish (chan still open)")
		}
	}()

	if execConfig.AttachStdin {
		in = cli.in
	}
	if execConfig.AttachStdout {
		out = cli.out
	}
	if execConfig.AttachStderr {
		if execConfig.Tty {
			stderr = cli.out
		} else {
			stderr = cli.err
		}
	}
	errCh = promise.Go(func() error {
		return cli.hijack("POST", "/exec/"+execID+"/start", execConfig.Tty, in, out, stderr, hijacked, execConfig)
	})

	// Acknowledge the hijack before starting
	select {
	case closer := <-hijacked:
		// Make sure that hijack gets closed when returning. (result
		// in closing hijack chan and freeing server's goroutines.
		if closer != nil {
			defer closer.Close()
		}
	case err := <-errCh:
		if err != nil {
			log.Debugf("Error hijack: %s", err)
			return err
		}
	}

	if execConfig.Tty && cli.isTerminalIn {
		if err := cli.monitorTtySize(execID, true); err != nil {
			log.Errorf("Error monitoring TTY size: %s", err)
		}
	}

	if err := <-errCh; err != nil {
		log.Debugf("Error hijack: %s", err)
		return err
	}

	var status int
	if _, status, err = getExecExitCode(cli, execID); err != nil {
		return err
	}

	if status != 0 {
		return &utils.StatusError{StatusCode: status}
	}

	return nil
}