- Runtime: ghost containers can be killed.

commands.go

@@ -836,6 +836,10 @@ func (srv *Server) CmdAttach(stdin io.ReadCloser, stdout rcli.DockerConn, args .
 		return fmt.Errorf("No such container: %s", name)
 	}
 
+	if container.State.Ghost {
+		return fmt.Errorf("Impossible to attach to a ghost container")
+	}
+
 	if container.Config.Tty {
 		stdout.SetOptionRawTerminal()
 	}

container.go

@@ -530,16 +530,42 @@ func (container *Container) releaseNetwork() {
 	container.NetworkSettings = &NetworkSettings{}
 }
 
+// FIXME: replace this with a control socket within docker-init
+func (container *Container) waitLxc() error {
+	for {
+		if output, err := exec.Command("lxc-info", "-n", container.Id).CombinedOutput(); err != nil {
+			return err
+		} else {
+			if !strings.Contains(string(output), "RUNNING") {
+				return nil
+			}
+		}
+		time.Sleep(500 * time.Millisecond)
+	}
+	return nil
+}
+
 func (container *Container) monitor() {
 	// Wait for the program to exit
 	Debugf("Waiting for process")
-	if err := container.cmd.Wait(); err != nil {
-		// Discard the error as any signals or non 0 returns will generate an error
-		Debugf("%s: Process: %s", container.Id, err)
+
+	// If the command does not exists, try to wait via lxc
+	if container.cmd == nil {
+		if err := container.waitLxc(); err != nil {
+			Debugf("%s: Process: %s", container.Id, err)
+		}
+	} else {
+		if err := container.cmd.Wait(); err != nil {
+			// Discard the error as any signals or non 0 returns will generate an error
+			Debugf("%s: Process: %s", container.Id, err)
+		}
 	}
 	Debugf("Process finished")
 
-	exitCode := container.cmd.ProcessState.Sys().(syscall.WaitStatus).ExitStatus()
+	var exitCode int = -1
+	if container.cmd != nil {
+		exitCode = container.cmd.ProcessState.Sys().(syscall.WaitStatus).ExitStatus()
+	}
 
 	// Cleanup
 	container.releaseNetwork()
@@ -588,7 +614,7 @@ func (container *Container) monitor() {
 }
 
 func (container *Container) kill() error {
-	if !container.State.Running || container.cmd == nil {
+	if !container.State.Running {
 		return nil
 	}
 
@@ -600,6 +626,9 @@ func (container *Container) kill() error {
 
 	// 2. Wait for the process to die, in last resort, try to kill the process directly
 	if err := container.WaitTimeout(10 * time.Second); err != nil {
+		if container.cmd == nil {
+			return fmt.Errorf("lxc-kill failed, impossible to kill the container %s", container.Id)
+		}
 		log.Printf("Container %s failed to exit within 10 seconds of lxc SIGKILL - trying direct SIGKILL", container.Id)
 		if err := container.cmd.Process.Kill(); err != nil {
 			return err
@@ -617,9 +646,6 @@ func (container *Container) Kill() error {
 	if !container.State.Running {
 		return nil
 	}
-	if container.State.Ghost {
-		return fmt.Errorf("Can't kill ghost container")
-	}
 	return container.kill()
 }
 
@@ -629,9 +655,6 @@ func (container *Container) Stop(seconds int) error {
 	if !container.State.Running {
 		return nil
 	}
-	if container.State.Ghost {
-		return fmt.Errorf("Can't stop ghost container")
-	}
 
 	// 1. Send a SIGTERM
 	if output, err := exec.Command("lxc-kill", "-n", container.Id, "15").CombinedOutput(); err != nil {

runtime.go

@@ -184,12 +184,6 @@ func (runtime *Runtime) Register(container *Container) error {
 		}
 	}
 
-	// If the container is not running or just has been flagged not running
-	// then close the wait lock chan (will be reset upon start)
-	if !container.State.Running {
-		close(container.waitLock)
-	}
-
 	// Even if not running, we init the lock (prevents races in start/stop/kill)
 	container.State.initLock()
 
@@ -207,6 +201,15 @@ func (runtime *Runtime) Register(container *Container) error {
 	// done
 	runtime.containers.PushBack(container)
 	runtime.idIndex.Add(container.Id)
+
+	// If the container is not running or just has been flagged not running
+	// then close the wait lock chan (will be reset upon start)
+	if !container.State.Running {
+		close(container.waitLock)
+	} else {
+		container.allocateNetwork()
+		go container.monitor()
+	}
 	return nil
 }