diff --git a/pkg/libcontainer/nsinit/exec.go b/pkg/libcontainer/nsinit/exec.go
index ef33d3a5a3..d4ce1ca8c4 100644
--- a/pkg/libcontainer/nsinit/exec.go
+++ b/pkg/libcontainer/nsinit/exec.go
@@ -19,17 +19,19 @@ var execCommand = cli.Command{
}
func execAction(context *cli.Context) {
- var (
- err error
- nspid, exitCode int
- )
+ var nspid, exitCode int
+
+ container, err := loadContainer()
+ if err != nil {
+ log.Fatal(err)
+ }
if nspid, err = readPid(); err != nil && !os.IsNotExist(err) {
log.Fatalf("unable to read pid: %s", err)
}
if nspid > 0 {
- exitCode, err = namespaces.ExecIn(container, nspid, []string(context.Args()))
+ err = namespaces.ExecIn(container, nspid, []string(context.Args()))
} else {
term := namespaces.NewTerminal(os.Stdin, os.Stdout, os.Stderr, container.Tty)
exitCode, err = startContainer(container, term, dataPath, []string(context.Args()))
diff --git a/pkg/libcontainer/nsinit/init.go b/pkg/libcontainer/nsinit/init.go
index 561b93bb71..20096f0218 100644
--- a/pkg/libcontainer/nsinit/init.go
+++ b/pkg/libcontainer/nsinit/init.go
@@ -22,6 +22,11 @@ var (
)
func initAction(context *cli.Context) {
+ container, err := loadContainer()
+ if err != nil {
+ log.Fatal(err)
+ }
+
rootfs, err := os.Getwd()
if err != nil {
log.Fatal(err)
diff --git a/pkg/libcontainer/nsinit/main.go b/pkg/libcontainer/nsinit/main.go
index 29b80bad49..20132de0e0 100644
--- a/pkg/libcontainer/nsinit/main.go
+++ b/pkg/libcontainer/nsinit/main.go
@@ -5,21 +5,15 @@ import (
"os"
"github.com/codegangsta/cli"
- "github.com/dotcloud/docker/pkg/libcontainer"
)
-var (
- container *libcontainer.Container
- logPath = os.Getenv("log")
-)
-
-func preload(context *cli.Context) (err error) {
- container, err = loadContainer()
- if err != nil {
- return err
- }
+var logPath = os.Getenv("log")
+func preload(context *cli.Context) error {
if logPath != "" {
+ if err := openLog(logPath); err != nil {
+ return err
+ }
}
return nil
@@ -37,6 +31,7 @@ func main() {
initCommand,
statsCommand,
specCommand,
+ nsenterCommand,
}
if err := app.Run(os.Args); err != nil {
diff --git a/pkg/libcontainer/nsinit/nsenter.go b/pkg/libcontainer/nsinit/nsenter.go
new file mode 100644
index 0000000000..54644282d4
--- /dev/null
+++ b/pkg/libcontainer/nsinit/nsenter.go
@@ -0,0 +1,40 @@
+package main
+
+import (
+ "log"
+ "strconv"
+
+ "github.com/codegangsta/cli"
+ "github.com/dotcloud/docker/pkg/libcontainer/namespaces"
+)
+
+var nsenterCommand = cli.Command{
+ Name: "nsenter",
+ Usage: "init process for entering an existing namespace",
+ Action: nsenterAction,
+}
+
+func nsenterAction(context *cli.Context) {
+ args := context.Args()
+ if len(args) < 4 {
+ log.Fatalf("incorrect usage: <pid> <process label> <container JSON> <cmd>...")
+ }
+
+ container, err := loadContainerFromJson(args.Get(2))
+ if err != nil {
+ log.Fatalf("unable to load container: %s", err)
+ }
+
+ nspid, err := strconv.Atoi(args.Get(0))
+ if err != nil {
+ log.Fatalf("unable to read pid: %s from %q", err, args.Get(0))
+ }
+
+ if nspid <= 0 {
+ log.Fatalf("cannot enter into namespaces without valid pid: %q", nspid)
+ }
+
+ if err := namespaces.NsEnter(container, args.Get(1), nspid, args[3:]); err != nil {
+ log.Fatalf("failed to nsenter: %s", err)
+ }
+}
diff --git a/pkg/libcontainer/nsinit/spec.go b/pkg/libcontainer/nsinit/spec.go
index 92a2f64cdc..2eb4da9fc5 100644
--- a/pkg/libcontainer/nsinit/spec.go
+++ b/pkg/libcontainer/nsinit/spec.go
@@ -4,7 +4,6 @@ import (
"encoding/json"
"fmt"
"log"
- "os"
"github.com/codegangsta/cli"
"github.com/dotcloud/docker/pkg/libcontainer"
@@ -17,15 +16,17 @@ var specCommand = cli.Command{
}
func specAction(context *cli.Context) {
- // returns the spec of the current container.
+ container, err := loadContainer()
+ if err != nil {
+ log.Fatal(err)
+ }
+
spec, err := getContainerSpec(container)
if err != nil {
- log.Printf("Failed to get spec - %v\n", err)
- os.Exit(1)
+ log.Fatalf("Failed to get spec - %v\n", err)
}
- fmt.Printf("Spec:\n%v\n", spec)
- os.Exit(0)
+ fmt.Printf("Spec:\n%v\n", spec)
}
// returns the container spec in json format.
@@ -34,5 +35,6 @@ func getContainerSpec(container *libcontainer.Container) (string, error) {
if err != nil {
return "", err
}
+
return string(spec), nil
}
diff --git a/pkg/libcontainer/nsinit/stats.go b/pkg/libcontainer/nsinit/stats.go
index 0e930823b1..023b40a822 100644
--- a/pkg/libcontainer/nsinit/stats.go
+++ b/pkg/libcontainer/nsinit/stats.go
@@ -4,7 +4,6 @@ import (
"encoding/json"
"fmt"
"log"
- "os"
"github.com/codegangsta/cli"
"github.com/dotcloud/docker/pkg/libcontainer"
@@ -18,14 +17,17 @@ var statsCommand = cli.Command{
}
func statsAction(context *cli.Context) {
- // returns the stats of the current container.
+ container, err := loadContainer()
+ if err != nil {
+ log.Fatal(err)
+ }
+
stats, err := getContainerStats(container)
if err != nil {
- log.Printf("Failed to get stats - %v\n", err)
- os.Exit(1)
+ log.Fatalf("Failed to get stats - %v\n", err)
}
+
fmt.Printf("Stats:\n%v\n", stats)
- os.Exit(0)
}
// returns the container stats in json format.
@@ -34,9 +36,11 @@ func getContainerStats(container *libcontainer.Container) (string, error) {
if err != nil {
return "", err
}
+
out, err := json.MarshalIndent(stats, "", "\t")
if err != nil {
return "", err
}
+
return string(out), nil
}
diff --git a/pkg/libcontainer/nsinit/utils.go b/pkg/libcontainer/nsinit/utils.go
index fc311a351d..9926e2721f 100644
--- a/pkg/libcontainer/nsinit/utils.go
+++ b/pkg/libcontainer/nsinit/utils.go
@@ -50,3 +50,13 @@ func openLog(name string) error {
return nil
}
+
+func loadContainerFromJson(rawData string) (*libcontainer.Container, error) {
+ var container *libcontainer.Container
+
+ if err := json.Unmarshal([]byte(rawData), &container); err != nil {
+ return nil, err
+ }
+
+ return container, nil
+}