Import nsenter in docker.

Docker-DCO-1.1-Signed-off-by: Vishnu Kannan <vishnuk@google.com> (github: vishh)

daemon/exec.go

@@ -18,8 +18,8 @@ import (
 
 type ExecConfig struct {
 	ProcessConfig execdriver.ProcessConfig
-	StreamConfig  StreamConfig
-	OpenStdin     bool
+	StreamConfig
+	OpenStdin bool
 }
 
 func (d *Daemon) ContainerExec(job *engine.Job) engine.Status {
@@ -92,7 +92,6 @@ func (d *Daemon) ContainerExec(job *engine.Job) engine.Status {
 		attachErr = d.Attach(&execConfig.StreamConfig, config.AttachStdin, false, config.Tty, cStdin, cStdinCloser, cStdout, cStderr)
 	}()
 
-	log.Debugf("Exec Config is %+v\n", execConfig)
 	go func() {
 		err := container.Exec(execConfig)
 		if err != nil {

daemon/execdriver/native/driver.go

@@ -22,6 +22,7 @@ import (
 	"github.com/docker/libcontainer/cgroups/systemd"
 	consolepkg "github.com/docker/libcontainer/console"
 	"github.com/docker/libcontainer/namespaces"
+	_ "github.com/docker/libcontainer/namespaces/nsenter"
 	"github.com/docker/libcontainer/system"
 )
 

daemon/execdriver/native/exec.go

@@ -37,6 +37,7 @@ func nsenterExec() {
 	}
 }
 
+// TODO(vishh): Add support for running in priviledged mode and running as a different user.
 func (d *driver) Exec(c *execdriver.Command, processConfig *execdriver.ProcessConfig, pipes *execdriver.Pipes, startCallback execdriver.StartCallback) (int, error) {
 	active := d.activeContainers[c.ID]
 	if active == nil {

runconfig/exec.go

@@ -15,7 +15,6 @@ type ExecConfig struct {
 	AttachStdout bool
 	Detach       bool
 	Cmd          []string
-	Hostname     string
 }
 
 func ExecConfigFromJob(job *engine.Job) *ExecConfig {
@@ -37,14 +36,11 @@ func ExecConfigFromJob(job *engine.Job) *ExecConfig {
 
 func ParseExec(cmd *flag.FlagSet, args []string) (*ExecConfig, error) {
 	var (
-		flPrivileged = cmd.Bool([]string{"#privileged", "-privileged"}, false, "Give extended privileges to this container")
-		flStdin      = cmd.Bool([]string{"i", "-interactive"}, false, "Keep STDIN open even if not attached")
-		flTty        = cmd.Bool([]string{"t", "-tty"}, false, "Allocate a pseudo-TTY")
-		flHostname   = cmd.String([]string{"h", "-hostname"}, "", "Container host name")
-		flUser       = cmd.String([]string{"u", "-user"}, "", "Username or UID")
-		flDetach     = cmd.Bool([]string{"d", "-detach"}, false, "Detached mode: run command in the background")
-		execCmd      []string
-		container    string
+		flStdin   = cmd.Bool([]string{"i", "-interactive"}, false, "Keep STDIN open even if not attached")
+		flTty     = cmd.Bool([]string{"t", "-tty"}, false, "Allocate a pseudo-TTY")
+		flDetach  = cmd.Bool([]string{"d", "-detach"}, false, "Detached mode: run command in the background")
+		execCmd   []string
+		container string
 	)
 	if err := cmd.Parse(args); err != nil {
 		return nil, err
@@ -56,12 +52,13 @@ func ParseExec(cmd *flag.FlagSet, args []string) (*ExecConfig, error) {
 	}
 
 	execConfig := &ExecConfig{
-		User:       *flUser,
-		Privileged: *flPrivileged,
+		// TODO(vishh): Expose '-u' flag once it is supported.
+		User: "",
+		// TODO(vishh): Expose '-p' flag once it is supported.
+		Privileged: false,
 		Tty:        *flTty,
 		Cmd:        execCmd,
 		Container:  container,
-		Hostname:   *flHostname,
 		Detach:     *flDetach,
 	}