Persistent directory for container in execdriver

This is needed for persistent namespaces

Signed-off-by: Alexandr Morozov <lk4d4math@gmail.com>

daemon/delete.go

@@ -115,6 +115,10 @@ func (daemon *Daemon) Destroy(container *Container) error {
 		return fmt.Errorf("Unable to remove filesystem for %v: %v", container.ID, err)
 	}
 
+	if err := daemon.execDriver.Clean(container.ID); err != nil {
+		return fmt.Errorf("Unable to remove execdriver data for %s: %s", container.ID, err)
+	}
+
 	selinuxFreeLxcContexts(container.ProcessLabel)
 
 	return nil

daemon/execdriver/driver.go

@@ -51,6 +51,7 @@ type Driver interface {
 	Info(id string) Info                          // "temporary" hack (until we move state from core to plugins)
 	GetPidsForContainer(id string) ([]int, error) // Returns a list of pids for the given container.
 	Terminate(c *Command) error                   // kill it with fire
+	Clean(id string) error                        // clean all traces of container exec
 }
 
 // Network settings of the container

daemon/execdriver/lxc/driver.go

@@ -457,6 +457,11 @@ func (d *driver) generateEnvConfig(c *execdriver.Command) error {
 	return ioutil.WriteFile(p, data, 0600)
 }
 
+// Clean not implemented for lxc
+func (d *driver) Clean(id string) error {
+	return nil
+}
+
 type TtyConsole struct {
 	MasterPty *os.File
 	SlavePty  *os.File

daemon/execdriver/native/driver.go

@@ -94,7 +94,7 @@ func (d *driver) Run(c *execdriver.Command, pipes *execdriver.Pipes, startCallba
 	if err := d.createContainerRoot(c.ID); err != nil {
 		return -1, err
 	}
-	defer d.removeContainerRoot(c.ID)
+	defer d.cleanContainer(c.ID)
 
 	if err := d.writeContainerFile(container, c.ID); err != nil {
 		return -1, err
@@ -186,7 +186,7 @@ func (d *driver) Terminate(p *execdriver.Command) error {
 		err = syscall.Kill(p.ProcessConfig.Process.Pid, 9)
 		syscall.Wait4(p.ProcessConfig.Process.Pid, nil, 0, nil)
 	}
-	d.removeContainerRoot(p.ID)
+	d.cleanContainer(p.ID)
 
 	return err
 
@@ -227,15 +227,18 @@ func (d *driver) writeContainerFile(container *libcontainer.Config, id string) e
 	return ioutil.WriteFile(filepath.Join(d.root, id, "container.json"), data, 0655)
 }
 
-func (d *driver) createContainerRoot(id string) error {
-	return os.MkdirAll(filepath.Join(d.root, id), 0655)
-}
-
-func (d *driver) removeContainerRoot(id string) error {
+func (d *driver) cleanContainer(id string) error {
 	d.Lock()
 	delete(d.activeContainers, id)
 	d.Unlock()
+	return os.RemoveAll(filepath.Join(d.root, id, "container.json"))
+}
+
+func (d *driver) createContainerRoot(id string) error {
+	return os.MkdirAll(filepath.Join(d.root, id), 0655)
+}
 
+func (d *driver) Clean(id string) error {
 	return os.RemoveAll(filepath.Join(d.root, id))
 }