Move runtime flags to struct

Signed-off-by: Evan Lezar <elezar@nvidia.com>

tools/container/nvidia-toolkit/run.go

@@ -31,14 +31,21 @@ var waitingForSignal = make(chan bool, 1)
 var signalReceived = make(chan bool, 1)
 
 var destinationArg string
-var noDaemonFlag bool
+
-var runtimeFlag string
+// options stores the command line arguments
-var runtimeArgsFlag string
+type options struct {
+	noDaemon    bool
+	runtime     string
+	runtimeArgs string
+}
 
 // Version defines the CLI version. This is set at build time using LD FLAGS
 var Version = "development"
 
 func main() {
+
+	options := options{}
+
 	// Create the top-level CLI
 	c := cli.NewApp()
 	c.Name = "nvidia-toolkit"
@@ -46,7 +53,9 @@ func main() {
 	c.UsageText = "DESTINATION [-n | --no-daemon] [-r | --runtime] [-u | --runtime-args]"
 	c.Description = "DESTINATION points to the host path underneath which the nvidia-container-toolkit should be installed.\nIt will be installed at ${DESTINATION}/toolkit"
 	c.Version = Version
-	c.Action = Run
+	c.Action = func(ctx *cli.Context) error {
+		return Run(ctx, &options)
+	}
 
 	// Setup flags for the CLI
 	c.Flags = []cli.Flag{
@@ -54,7 +63,7 @@ func main() {
 			Name:        "no-daemon",
 			Aliases:     []string{"n"},
 			Usage:       "terminate immediatly after setting up the runtime. Note that no cleanup will be performed",
-			Destination: &noDaemonFlag,
+			Destination: &options.noDaemon,
 			EnvVars:     []string{"NO_DAEMON"},
 		},
 		&cli.StringFlag{
@@ -62,7 +71,7 @@ func main() {
 			Aliases:     []string{"r"},
 			Usage:       "the runtime to setup on this node. One of {'docker', 'crio', 'containerd'}",
 			Value:       defaultRuntime,
-			Destination: &runtimeFlag,
+			Destination: &options.runtime,
 			EnvVars:     []string{"RUNTIME"},
 		},
 		&cli.StringFlag{
@@ -70,7 +79,7 @@ func main() {
 			Aliases:     []string{"u"},
 			Usage:       "arguments to pass to 'docker', 'crio', or 'containerd' setup command",
 			Value:       defaultRuntimeArgs,
-			Destination: &runtimeArgsFlag,
+			Destination: &options.runtimeArgs,
 			EnvVars:     []string{"RUNTIME_ARGS"},
 		},
 	}
@@ -93,8 +102,8 @@ func main() {
 }
 
 // Run runs the core logic of the CLI
-func Run(c *cli.Context) error {
+func Run(c *cli.Context, o *options) error {
-	err := verifyFlags()
+	err := verifyFlags(o)
 	if err != nil {
 		return fmt.Errorf("unable to verify flags: %v", err)
 	}
@@ -110,18 +119,18 @@ func Run(c *cli.Context) error {
 		return fmt.Errorf("unable to install toolkit: %v", err)
 	}
 
-	err = setupRuntime()
+	err = setupRuntime(o)
 	if err != nil {
 		return fmt.Errorf("unable to setup runtime: %v", err)
 	}
 
-	if !noDaemonFlag {
+	if !o.noDaemon {
 		err = waitForSignal()
 		if err != nil {
 			return fmt.Errorf("unable to wait for signal: %v", err)
 		}
 
-		err = cleanupRuntime()
+		err = cleanupRuntime(o)
 		if err != nil {
 			return fmt.Errorf("unable to cleanup runtime: %v", err)
 		}
@@ -166,10 +175,10 @@ func ParseArgs(args []string) ([]string, error) {
 	return append([]string{args[0]}, args[numPositionalArgs:]...), nil
 }
 
-func verifyFlags() error {
+func verifyFlags(o *options) error {
 	log.Infof("Verifying Flags")
-	if _, exists := availableRuntimes[runtimeFlag]; !exists {
+	if _, exists := availableRuntimes[o.runtime]; !exists {
-		return fmt.Errorf("unknown runtime: %v", runtimeFlag)
+		return fmt.Errorf("unknown runtime: %v", o.runtime)
 	}
 	return nil
 }
@@ -232,19 +241,19 @@ func installToolkit() error {
 	return nil
 }
 
-func setupRuntime() error {
+func setupRuntime(o *options) error {
 	toolkitDir := filepath.Join(destinationArg, toolkitSubDir)
 
 	log.Infof("Setting up runtime")
 
-	cmdline := fmt.Sprintf("%v setup %v %v\n", runtimeFlag, runtimeArgsFlag, toolkitDir)
+	cmdline := fmt.Sprintf("%v setup %v %v\n", o.runtime, o.runtimeArgs, toolkitDir)
 
 	cmd := exec.Command("sh", "-c", cmdline)
 	cmd.Stdout = os.Stdout
 	cmd.Stderr = os.Stderr
 	err := cmd.Run()
 	if err != nil {
-		return fmt.Errorf("error running %v command: %v", runtimeFlag, err)
+		return fmt.Errorf("error running %v command: %v", o.runtime, err)
 	}
 
 	return nil
@@ -257,19 +266,19 @@ func waitForSignal() error {
 	return nil
 }
 
-func cleanupRuntime() error {
+func cleanupRuntime(o *options) error {
 	toolkitDir := filepath.Join(destinationArg, toolkitSubDir)
 
 	log.Infof("Cleaning up Runtime")
 
-	cmdline := fmt.Sprintf("%v cleanup %v %v\n", runtimeFlag, runtimeArgsFlag, toolkitDir)
+	cmdline := fmt.Sprintf("%v cleanup %v %v\n", o.runtime, o.runtimeArgs, toolkitDir)
 
 	cmd := exec.Command("sh", "-c", cmdline)
 	cmd.Stdout = os.Stdout
 	cmd.Stderr = os.Stderr
 	err := cmd.Run()
 	if err != nil {
-		return fmt.Errorf("error running %v command: %v", runtimeFlag, err)
+		return fmt.Errorf("error running %v command: %v", o.runtime, err)
 	}
 
 	return nil