Merge pull request #541 from crosbymichael/ids

Require container id as arg1

README.md

@@ -65,9 +65,11 @@ You can also run specific test cases by:
 
 ### Using:
 
-To run a container, execute `runc start` in the bundle's root directory:
+To run a container with the id "test", execute `runc start` with the containers id as arg one 
+in the bundle's root directory:
+
 ```bash
-runc start
+runc start test
 / $ ps
 PID   USER     COMMAND
 1     daemon   sh
@@ -98,7 +100,7 @@ tar -C rootfs -xf busybox.tar
 * Create `config.json` by using `runc spec`.
 * Execute `runc start` and you should be placed into a shell where you can run `ps`:
 ```
-$ runc start
+$ runc start test
 / # ps
 PID   USER     COMMAND
     1 root     sh
@@ -120,7 +122,7 @@ After=network.target
 [Service]
 CPUQuota=200%
 MemoryLimit=1536M
-ExecStart=/usr/local/bin/runc start
+ExecStart=/usr/local/bin/runc start minecraft
 Restart=on-failure
 WorkingDirectory=/containers/minecraftbuild
 

exec.go

@@ -128,7 +128,7 @@ func getProcess(context *cli.Context, bundle string) (*specs.Process, error) {
 		return nil, err
 	}
 	p := spec.Process
-	p.Args = context.Args()
+	p.Args = context.Args()[1:]
 	// override the cwd, if passed
 	if context.String("cwd") != "" {
 		p.Cwd = context.String("cwd")

kill.go

@@ -58,7 +58,7 @@ var killCommand = cli.Command{
 			fatal(err)
 		}
 
-		sigstr := context.Args().First()
+		sigstr := context.Args().Get(1)
 		if sigstr == "" {
 			sigstr = "SIGTERM"
 		}

main.go

@@ -10,7 +10,7 @@ import (
 )
 
 const (
-	version    = "0.0.7"
+	version    = "0.0.8"
 	specConfig = "config.json"
 	usage      = `Open Container Initiative runtime
 	
@@ -27,7 +27,7 @@ After creating config files for your root filesystem with runc, you can execute
 a container in your shell by running:
 
     # cd /mycontainer
-    # runc start [ -b bundle ] 
+    # runc start [ -b bundle ] <container-id>
 
 If not specified, the default value for the 'bundle' is the current directory.
 'Bundle' is the directory where '` + specConfig + `' must be located.`
@@ -39,11 +39,6 @@ func main() {
 	app.Usage = usage
 	app.Version = fmt.Sprintf("%s\nspec version %s", version, specs.Version)
 	app.Flags = []cli.Flag{
-		cli.StringFlag{
-			Name:  "id",
-			Value: getDefaultID(),
-			Usage: "specify the ID to be used for the container",
-		},
 		cli.BoolFlag{
 			Name:  "debug",
 			Usage: "enable debug output for logging",

main_unsupported.go

@@ -7,10 +7,6 @@ import (
 	"github.com/codegangsta/cli"
 )
 
-func getDefaultID() string {
-	return ""
-}
-
 var (
 	checkpointCommand cli.Command
 	eventsCommand     cli.Command

restore.go

@@ -66,6 +66,10 @@ var restoreCommand = cli.Command{
 	},
 	Action: func(context *cli.Context) {
 		imagePath := context.String("image-path")
+		id := context.Args().First()
+		if id == "" {
+			fatal(errEmptyID)
+		}
 		if imagePath == "" {
 			imagePath = getDefaultImagePath(context)
 		}
@@ -79,7 +83,7 @@ var restoreCommand = cli.Command{
 		if err != nil {
 			fatal(err)
 		}
-		config, err := createLibcontainerConfig(context.GlobalString("id"), spec)
+		config, err := createLibcontainerConfig(id, spec)
 		if err != nil {
 			fatal(err)
 		}
@@ -92,14 +96,17 @@ var restoreCommand = cli.Command{
 }
 
 func restoreContainer(context *cli.Context, spec *specs.LinuxSpec, config *configs.Config, imagePath string) (code int, err error) {
-	rootuid := 0
+	var (
+		rootuid = 0
+		id      = context.Args().First()
+	)
 	factory, err := loadFactory(context)
 	if err != nil {
 		return -1, err
 	}
-	container, err := factory.Load(context.GlobalString("id"))
+	container, err := factory.Load(id)
 	if err != nil {
-		container, err = factory.Create(context.GlobalString("id"), config)
+		container, err = factory.Create(id, config)
 		if err != nil {
 			return -1, err
 		}
@@ -111,7 +118,7 @@ func restoreContainer(context *cli.Context, spec *specs.LinuxSpec, config *confi
 		logrus.Error(err)
 	}
 	if status == libcontainer.Running {
-		fatal(fmt.Errorf("Container with id %s already running", context.GlobalString("id")))
+		fatal(fmt.Errorf("Container with id %s already running", id))
 	}
 
 	setManageCgroupsMode(context, options)

start.go

@@ -84,13 +84,17 @@ func init() {
 }
 
 func startContainer(context *cli.Context, spec *specs.LinuxSpec) (int, error) {
-	config, err := createLibcontainerConfig(context.GlobalString("id"), spec)
+	id := context.Args().First()
+	if id == "" {
+		return -1, errEmptyID
+	}
+	config, err := createLibcontainerConfig(id, spec)
 	if err != nil {
 		return -1, err
 	}
 	if _, err := os.Stat(config.Rootfs); err != nil {
 		if os.IsNotExist(err) {
-			return -1, fmt.Errorf("Rootfs (%q) does not exist", config.Rootfs)
+			return -1, fmt.Errorf("rootfs (%q) does not exist", config.Rootfs)
 		}
 		return -1, err
 	}
@@ -102,7 +106,7 @@ func startContainer(context *cli.Context, spec *specs.LinuxSpec) (int, error) {
 	if err != nil {
 		return -1, err
 	}
-	container, err := factory.Create(context.GlobalString("id"), config)
+	container, err := factory.Create(id, config)
 	if err != nil {
 		return -1, err
 	}

utils.go

@@ -3,6 +3,7 @@
 package main
 
 import (
+	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -17,6 +18,8 @@ import (
 
 const wildcard = -1
 
+var errEmptyID = errors.New("container id cannot be empty")
+
 var allowedDevices = []*configs.Device{
 	// allow mknod for any device
 	{
@@ -160,15 +163,15 @@ func loadFactory(context *cli.Context) (libcontainer.Factory, error) {
 // getContainer returns the specified container instance by loading it from state
 // with the default factory.
 func getContainer(context *cli.Context) (libcontainer.Container, error) {
-	factory, err := loadFactory(context)
-	if err != nil {
-		return nil, err
+	id := context.Args().First()
+	if id == "" {
+		return nil, errEmptyID
 	}
-	container, err := factory.Load(context.GlobalString("id"))
+	factory, err := loadFactory(context)
 	if err != nil {
 		return nil, err
 	}
-	return container, nil
+	return factory.Load(id)
 }
 
 // fatal prints the error's details if it is a libcontainer specific error type
@@ -182,17 +185,6 @@ func fatal(err error) {
 	os.Exit(1)
 }
 
-// getDefaultID returns a string to be used as the container id based on the
-// current working directory of the runc process.  This function panics
-// if the cwd is unable to be found based on a system error.
-func getDefaultID() string {
-	cwd, err := os.Getwd()
-	if err != nil {
-		panic(err)
-	}
-	return filepath.Base(cwd)
-}
-
 func getDefaultImagePath(context *cli.Context) string {
 	cwd, err := os.Getwd()
 	if err != nil {