@@ -7,6 +7,7 @@ import (

 	"io/ioutil"

 	"log"

 	"os"

+	"runtime"

 	"strings"

 	"github.com/dotcloud/docker/api"

@@ -121,7 +122,10 @@ func main() {

 			}

 		}

-		eng, err := engine.New(realRoot)

+		if err := checkKernelAndArch(); err != nil {

+			log.Fatal(err)

+		}

+		eng, err := engine.New()

 		if err != nil {

 			log.Fatal(err)

 		}

@@ -239,3 +243,27 @@ func main() {

 func showVersion() {

 	fmt.Printf("Docker version %s, build %s\n", dockerversion.VERSION, dockerversion.GITCOMMIT)

 }

+

+func checkKernelAndArch() error {

+	// Check for unsupported architectures

+	if runtime.GOARCH != "amd64" {

+		return fmt.Errorf("The docker runtime currently only supports amd64 (not %s). This will change in the future. Aborting.", runtime.GOARCH)

+	}

+	// Check for unsupported kernel versions

+	// FIXME: it would be cleaner to not test for specific versions, but rather

+	// test for specific functionalities.

+	// Unfortunately we can't test for the feature "does not cause a kernel panic"

+	// without actually causing a kernel panic, so we need this workaround until

+	// the circumstances of pre-3.8 crashes are clearer.

+	// For details see http://github.com/dotcloud/docker/issues/407

+	if k, err := utils.GetKernelVersion(); err != nil {

+		log.Printf("WARNING: %s\n", err)

+	} else {

+		if utils.CompareKernelVersion(k, &utils.KernelVersionInfo{Kernel: 3, Major: 8, Minor: 0}) < 0 {

+			if os.Getenv("DOCKER_NOWARN_KERNEL_VERSION") == "" {

+				log.Printf("WARNING: You are running linux kernel version %s, which might be unstable running docker. Please upgrade your kernel to 3.8.0.", k.String())

+			}

+		}

+	}

+	return nil

+}

@@ -5,9 +5,7 @@ import (

 	"fmt"

 	"github.com/dotcloud/docker/utils"

 	"io"

-	"log"

 	"os"

-	"runtime"

 	"sort"

 	"strings"

 )

@@ -37,7 +35,6 @@ func unregister(name string) {

 // It acts as a store for *containers*, and allows manipulation of these

 // containers by executing *jobs*.

 type Engine struct {

-	root     string

 	handlers map[string]Handler

 	hack     Hack // data for temporary hackery (see hack.go)

 	id       string

@@ -47,10 +44,6 @@ type Engine struct {

 	Logging  bool

 }

-func (eng *Engine) Root() string {

-	return eng.root

-}

-

 func (eng *Engine) Register(name string, handler Handler) error {

 	_, exists := eng.handlers[name]

 	if exists {

@@ -60,38 +53,9 @@ func (eng *Engine) Register(name string, handler Handler) error {

 	return nil

 }

-// New initializes a new engine managing the directory specified at `root`.

-// `root` is used to store containers and any other state private to the engine.

-// Changing the contents of the root without executing a job will cause unspecified

-// behavior.

-func New(root string) (*Engine, error) {

-	// Check for unsupported architectures

-	if runtime.GOARCH != "amd64" {

-		return nil, fmt.Errorf("The docker runtime currently only supports amd64 (not %s). This will change in the future. Aborting.", runtime.GOARCH)

-	}

-	// Check for unsupported kernel versions

-	// FIXME: it would be cleaner to not test for specific versions, but rather

-	// test for specific functionalities.

-	// Unfortunately we can't test for the feature "does not cause a kernel panic"

-	// without actually causing a kernel panic, so we need this workaround until

-	// the circumstances of pre-3.8 crashes are clearer.

-	// For details see http://github.com/dotcloud/docker/issues/407

-	if k, err := utils.GetKernelVersion(); err != nil {

-		log.Printf("WARNING: %s\n", err)

-	} else {

-		if utils.CompareKernelVersion(k, &utils.KernelVersionInfo{Kernel: 3, Major: 8, Minor: 0}) < 0 {

-			if os.Getenv("DOCKER_NOWARN_KERNEL_VERSION") == "" {

-				log.Printf("WARNING: You are running linux kernel version %s, which might be unstable running docker. Please upgrade your kernel to 3.8.0.", k.String())

-			}

-		}

-	}

-

-	if err := os.MkdirAll(root, 0700); err != nil && !os.IsExist(err) {

-		return nil, err

-	}

-

+// New initializes a new engine.

+func New() (*Engine, error) {

 	eng := &Engine{

-		root:     root,

 		handlers: make(map[string]Handler),

 		id:       utils.RandomString(),

 		Stdout:   os.Stdout,

@@ -113,7 +77,7 @@ func New(root string) (*Engine, error) {

 }

 func (eng *Engine) String() string {

-	return fmt.Sprintf("%s|%s", eng.Root(), eng.id[:8])

+	return fmt.Sprintf("%s", eng.id[:8])

 }

 // Commands returns a list of all currently registered commands,

@@ -2,10 +2,6 @@ package engine

 import (

 	"bytes"

-	"io/ioutil"

-	"os"

-	"path"

-	"path/filepath"

 	"strings"

 	"testing"

 )

@@ -67,7 +63,6 @@ func TestJob(t *testing.T) {

 func TestEngineCommands(t *testing.T) {

 	eng := newTestEngine(t)

-	defer os.RemoveAll(eng.Root())

 	handler := func(job *Job) Status { return StatusOK }

 	eng.Register("foo", handler)

 	eng.Register("bar", handler)

@@ -83,44 +78,9 @@ func TestEngineCommands(t *testing.T) {

 	}

 }

-func TestEngineRoot(t *testing.T) {

-	tmp, err := ioutil.TempDir("", "docker-test-TestEngineCreateDir")

-	if err != nil {

-		t.Fatal(err)

-	}

-	defer os.RemoveAll(tmp)

-	// We expect Root to resolve to an absolute path.

-	// FIXME: this should not be necessary.

-	// Until the above FIXME is implemented, let's check for the

-	// current behavior.

-	tmp, err = filepath.EvalSymlinks(tmp)

-	if err != nil {

-		t.Fatal(err)

-	}

-	tmp, err = filepath.Abs(tmp)

-	if err != nil {

-		t.Fatal(err)

-	}

-	dir := path.Join(tmp, "dir")

-	eng, err := New(dir)

-	if err != nil {

-		t.Fatal(err)

-	}

-	if st, err := os.Stat(dir); err != nil {

-		t.Fatal(err)

-	} else if !st.IsDir() {

-		t.Fatalf("engine.New() created something other than a directory at %s", dir)

-	}

-	if r := eng.Root(); r != dir {

-		t.Fatalf("Expected: %v\nReceived: %v", dir, r)

-	}

-}

-

 func TestEngineString(t *testing.T) {

 	eng1 := newTestEngine(t)

-	defer os.RemoveAll(eng1.Root())

 	eng2 := newTestEngine(t)

-	defer os.RemoveAll(eng2.Root())

 	s1 := eng1.String()

 	s2 := eng2.String()

 	if eng1 == eng2 {

@@ -130,7 +90,6 @@ func TestEngineString(t *testing.T) {

 func TestEngineLogf(t *testing.T) {

 	eng := newTestEngine(t)

-	defer os.RemoveAll(eng.Root())

 	input := "Test log line"

 	if n, err := eng.Logf("%s\n", input); err != nil {

 		t.Fatal(err)

@@ -141,7 +100,6 @@ func TestEngineLogf(t *testing.T) {

 func TestParseJob(t *testing.T) {

 	eng := newTestEngine(t)

-	defer os.RemoveAll(eng.Root())

 	// Verify that the resulting job calls to the right place

 	var called bool

 	eng.Register("echo", func(job *Job) Status {

@@ -1,18 +1,13 @@

 package engine

 import (

-	"github.com/dotcloud/docker/utils"

 	"testing"

 )

 var globalTestID string

 func newTestEngine(t *testing.T) *Engine {

-	tmp, err := utils.TestDirectory("")

-	if err != nil {

-		t.Fatal(err)

-	}

-	eng, err := New(tmp)

+	eng, err := New()

 	if err != nil {

 		t.Fatal(err)

 	}

@@ -1,13 +1,11 @@

 package engine

 import (

-	"os"

 	"testing"

 )

 func TestJobStatusOK(t *testing.T) {

 	eng := newTestEngine(t)

-	defer os.RemoveAll(eng.Root())

 	eng.Register("return_ok", func(job *Job) Status { return StatusOK })

 	err := eng.Job("return_ok").Run()

 	if err != nil {

@@ -17,7 +15,6 @@ func TestJobStatusOK(t *testing.T) {

 func TestJobStatusErr(t *testing.T) {

 	eng := newTestEngine(t)

-	defer os.RemoveAll(eng.Root())

 	eng.Register("return_err", func(job *Job) Status { return StatusErr })

 	err := eng.Job("return_err").Run()

 	if err == nil {

@@ -27,7 +24,6 @@ func TestJobStatusErr(t *testing.T) {

 func TestJobStatusNotFound(t *testing.T) {

 	eng := newTestEngine(t)

-	defer os.RemoveAll(eng.Root())

 	eng.Register("return_not_found", func(job *Job) Status { return StatusNotFound })

 	err := eng.Job("return_not_found").Run()

 	if err == nil {

@@ -37,7 +33,6 @@ func TestJobStatusNotFound(t *testing.T) {

 func TestJobStdoutString(t *testing.T) {

 	eng := newTestEngine(t)

-	defer os.RemoveAll(eng.Root())

 	// FIXME: test multiple combinations of output and status

 	eng.Register("say_something_in_stdout", func(job *Job) Status {

 		job.Printf("Hello world\n")

@@ -59,7 +54,6 @@ func TestJobStdoutString(t *testing.T) {

 func TestJobStderrString(t *testing.T) {

 	eng := newTestEngine(t)

-	defer os.RemoveAll(eng.Root())

 	// FIXME: test multiple combinations of output and status

 	eng.Register("say_something_in_stderr", func(job *Job) Status {

 		job.Errorf("Warning, something might happen\nHere it comes!\nOh no...\nSomething happened\n")

@@ -627,10 +627,9 @@ func TestRestore(t *testing.T) {

 	// Here are are simulating a docker restart - that is, reloading all containers

 	// from scratch

-	eng = newTestEngine(t, false, eng.Root())

-	daemon2 := mkDaemonFromEngine(eng, t)

-	if len(daemon2.List()) != 2 {

-		t.Errorf("Expected 2 container, %v found", len(daemon2.List()))

+	eng = newTestEngine(t, false, runtime.Config().Root)

+	if len(runtime2.List()) != 2 {

+		t.Errorf("Expected 2 container, %v found", len(runtime2.List()))

 	}

 	runningCount := 0

 	for _, c := range daemon2.List() {

@@ -149,7 +149,7 @@ func TestRestartKillWait(t *testing.T) {

 		t.Fatal(err)

 	}

-	eng = newTestEngine(t, false, eng.Root())

+	eng = newTestEngine(t, false, runtime.Config().Root)

 	srv = mkServerFromEngine(eng, t)

 	job = srv.Eng.Job("containers")

@@ -181,7 +181,7 @@ func newTestEngine(t utils.Fataler, autorestart bool, root string) *engine.Engin

 			root = dir

 		}

 	}

-	eng, err := engine.New(root)

+	eng, err := engine.New()

 	if err != nil {

 		t.Fatal(err)

 	}