Integrate new structure into docker's native driver

This duplicates some of the Exec code but I think it it worth it because
the native driver is more straight forward and does not have the
complexity have handling the type issues for now.
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)

nsinit/exec.go

@@ -3,11 +3,8 @@
 package nsinit
 
 import (
-	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
-	"path/filepath"
 	"syscall"
 
 	"github.com/dotcloud/docker/pkg/cgroups"
@@ -160,26 +157,6 @@ func InitializeNetworking(container *libcontainer.Container, nspid int, pipe *Sy
 	return pipe.SendToChild(context)
 }
 
-// WritePid writes the namespaced processes pid to pid and it's start time
-// to the path specified
-func WritePid(path string, pid int, startTime string) error {
-	err := ioutil.WriteFile(filepath.Join(path, "pid"), []byte(fmt.Sprint(pid)), 0655)
-	if err != nil {
-		return err
-	}
-	return ioutil.WriteFile(filepath.Join(path, "start"), []byte(startTime), 0655)
-}
-
-// DeletePid removes the pid and started file from disk when the container's process
-// dies and the container is cleanly removed
-func DeletePid(path string) error {
-	err := os.Remove(filepath.Join(path, "pid"))
-	if serr := os.Remove(filepath.Join(path, "start")); err == nil {
-		err = serr
-	}
-	return err
-}
-
 // GetNamespaceFlags parses the container's Namespaces options to set the correct
 // flags on clone, unshare, and setns
 func GetNamespaceFlags(namespaces libcontainer.Namespaces) (flag int) {

nsinit/pid.go

@@ -0,0 +1,28 @@
+package nsinit
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+)
+
+// WritePid writes the namespaced processes pid to pid and it's start time
+// to the path specified
+func WritePid(path string, pid int, startTime string) error {
+	err := ioutil.WriteFile(filepath.Join(path, "pid"), []byte(fmt.Sprint(pid)), 0655)
+	if err != nil {
+		return err
+	}
+	return ioutil.WriteFile(filepath.Join(path, "start"), []byte(startTime), 0655)
+}
+
+// DeletePid removes the pid and started file from disk when the container's process
+// dies and the container is cleanly removed
+func DeletePid(path string) error {
+	err := os.Remove(filepath.Join(path, "pid"))
+	if serr := os.Remove(filepath.Join(path, "start")); err == nil {
+		err = serr
+	}
+	return err
+}

nsinit/unsupported.go

@@ -3,9 +3,22 @@
 package nsinit
 
 import (
+	"github.com/dotcloud/docker/pkg/cgroups"
 	"github.com/dotcloud/docker/pkg/libcontainer"
 )
 
+func Init(container *libcontainer.Container, uncleanRootfs, consolePath string, syncPipe *SyncPipe, args []string) error {
+	return libcontainer.ErrUnsupported
+}
+
+func InitializeNetworking(container *libcontainer.Container, nspid int, pipe *SyncPipe) error {
+	return libcontainer.ErrUnsupported
+}
+
+func SetupCgroups(container *libcontainer.Container, nspid int) (cgroups.ActiveCgroup, error) {
+	return nil, libcontainer.ErrUnsupported
+}
+
 func GetNamespaceFlags(namespaces libcontainer.Namespaces) (flag int) {
 	return 0
 }