Finalize driver interfaces

Upstream-commit: ed572b457d28101b6ef465e5a3e221ee1fc7d48a
Component: engine

components/engine/aufs/aufs.go

@@ -2,6 +2,7 @@ package aufs
 
 import (
 	"fmt"
+	"github.com/dotcloud/docker/archive"
 	"github.com/dotcloud/docker/graphdriver"
 	"log"
 	"os"
@@ -14,6 +15,7 @@ func init() {
 }
 
 type AufsDriver struct {
+	root string
 }
 
 // New returns a new AUFS driver.
@@ -23,17 +25,54 @@ func Init(root string) (graphdriver.Driver, error) {
 	if err := exec.Command("modprobe", "aufs").Run(); err != nil {
 		return nil, err
 	}
-	return &AufsDriver{}, nil
+	return &AufsDriver{root}, nil
 }
 
-func (a *AufsDriver) Mount(img graphdriver.Image, root string) error {
-	layers, err := img.Layers()
+func (a *AufsDriver) OnCreate(dir graphdriver.Dir, layer archive.Archive) error {
+	tmp := path.Join(os.TempDir(), dir.ID())
+	if err := os.MkdirAll(tmp, 0755); err != nil {
+		return err
+	}
+	defer os.RemoveAll(tmp)
+
+	layerRoot := path.Join(a.root, dir.ID())
+	if err := os.MkdirAll(layerRoot, 0755); err != nil {
+		return err
+	}
+
+	if layer != nil {
+		if err := archive.Untar(layer, tmp); err != nil {
+			return err
+		}
+	}
+
+	if err := os.Rename(tmp, layerRoot); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (a *AufsDriver) OnRemove(dir graphdriver.Dir) error {
+	tmp := path.Join(os.TempDir(), dir.ID())
+
+	if err := os.MkdirAll(tmp, 0755); err != nil {
+		return err
+	}
+
+	if err := os.Rename(path.Join(a.root, dir.ID()), tmp); err != nil {
+		return err
+	}
+	return os.RemoveAll(tmp)
+}
+
+func (a *AufsDriver) OnMount(dir graphdriver.Dir, dest string) error {
+	layers, err := a.getLayers(dir)
 	if err != nil {
 		return err
 	}
 
-	target := path.Join(root, "rootfs")
-	rw := path.Join(root, "rw")
+	target := path.Join(dest, "rootfs")
+	rw := path.Join(dest, "rw")
 
 	// Create the target directories if they don't exist
 	if err := os.Mkdir(target, 0755); err != nil && !os.IsExist(err) {
@@ -48,8 +87,8 @@ func (a *AufsDriver) Mount(img graphdriver.Image, root string) error {
 	return nil
 }
 
-func (a *AufsDriver) Unmount(root string) error {
-	target := path.Join(root, "rootfs")
+func (a *AufsDriver) OnUnmount(dest string) error {
+	target := path.Join(dest, "rootfs")
 	if _, err := os.Stat(target); err != nil {
 		if os.IsNotExist(err) {
 			return nil
@@ -59,8 +98,32 @@ func (a *AufsDriver) Unmount(root string) error {
 	return Unmount(target)
 }
 
-func (a *AufsDriver) Mounted(root string) (bool, error) {
-	return Mounted(path.Join(root, "rootfs"))
+func (a *AufsDriver) Mounted(dest string) (bool, error) {
+	return Mounted(path.Join(dest, "rootfs"))
+}
+
+func (a *AufsDriver) Layer(dir graphdriver.Dir, dest string) (archive.Archive, error) {
+	return nil, fmt.Errorf("not implemented")
+}
+
+func (a *AufsDriver) Cleanup() error {
+	return nil
+}
+
+func (a *AufsDriver) getLayers(dir graphdriver.Dir) ([]string, error) {
+	var (
+		err     error
+		layers  = []string{}
+		current = dir
+	)
+
+	for current != nil {
+		layers = append(layers, current.Path())
+		if current, err = current.Parent(); err != nil {
+			return nil, err
+		}
+	}
+	return layers, nil
 }
 
 func (a *AufsDriver) aufsMount(ro []string, rw, target string) error {