cmd: Fix issues raised by Golangci

Issues included:

- unreachable code
- unneeded type assertions
- unhandled errors
- use of deprecated API
- unused code

https://github.com/containers/toolbox/pull/979

src/cmd/create.go

@@ -31,7 +31,7 @@ import (
 	"github.com/godbus/dbus/v5"
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
-	"golang.org/x/crypto/ssh/terminal"
+	"golang.org/x/term"
 )
 
 const (
@@ -445,7 +445,7 @@ func createContainer(container, image, release string, showCommandToEnter bool)
 
 	stdoutFd := os.Stdout.Fd()
 	stdoutFdInt := int(stdoutFd)
-	if logLevel := logrus.GetLevel(); logLevel < logrus.DebugLevel && terminal.IsTerminal(stdoutFdInt) {
+	if logLevel := logrus.GetLevel(); logLevel < logrus.DebugLevel && term.IsTerminal(stdoutFdInt) {
 		s.Prefix = fmt.Sprintf("Creating container %s: ", container)
 		s.Writer = os.Stdout
 		s.Start()
@@ -627,30 +627,6 @@ func getServiceSocket(serviceName string, unitName string) (string, error) {
 	return "", fmt.Errorf("failed to find a SOCK_STREAM socket for %s", unitName)
 }
 
-func isPathReadWrite(path string) (bool, error) {
-	logrus.Debugf("Checking if %s is mounted read-only or read-write", path)
-
-	mountPoint, err := utils.GetMountPoint(path)
-	if err != nil {
-		return false, fmt.Errorf("failed to get the mount-point of %s: %s", path, err)
-	}
-
-	logrus.Debugf("Mount-point of %s is %s", path, mountPoint)
-
-	mountFlags, err := utils.GetMountOptions(mountPoint)
-	if err != nil {
-		return false, fmt.Errorf("failed to get the mount options of %s: %s", mountPoint, err)
-	}
-
-	logrus.Debugf("Mount flags of %s on the host are %s", path, mountFlags)
-
-	if !strings.Contains(mountFlags, "ro") {
-		return true, nil
-	}
-
-	return false, nil
-}
-
 func pullImage(image, release string) (bool, error) {
 	if ok := utils.ImageReferenceCanBeID(image); ok {
 		logrus.Debugf("Looking for image %s", image)
@@ -718,7 +694,7 @@ func pullImage(image, release string) (bool, error) {
 
 	stdoutFd := os.Stdout.Fd()
 	stdoutFdInt := int(stdoutFd)
-	if logLevel := logrus.GetLevel(); logLevel < logrus.DebugLevel && terminal.IsTerminal(stdoutFdInt) {
+	if logLevel := logrus.GetLevel(); logLevel < logrus.DebugLevel && term.IsTerminal(stdoutFdInt) {
 		s := spinner.New(spinner.CharSets[9], 500*time.Millisecond)
 		s.Prefix = fmt.Sprintf("Pulling %s: ", imageFull)
 		s.Writer = os.Stdout

src/cmd/initContainer.go

@@ -85,7 +85,10 @@ func init() {
 		"home",
 		"",
 		"Create a user inside the toolbox container whose login directory is HOME")
-	initContainerCmd.MarkFlagRequired("home")
+	err := initContainerCmd.MarkFlagRequired("home")
+	if err != nil {
+		panic("Could not mark flag --home as required")
+	}
 
 	flags.BoolVar(&initContainerFlags.homeLink,
 		"home-link",
@@ -108,19 +111,28 @@ func init() {
 		"shell",
 		"",
 		"Create a user inside the toolbox container whose login shell is SHELL")
-	initContainerCmd.MarkFlagRequired("shell")
+	err = initContainerCmd.MarkFlagRequired("shell")
+	if err != nil {
+		panic("Could not mark flag --shell as required")
+	}
 
 	flags.IntVar(&initContainerFlags.uid,
 		"uid",
 		0,
 		"Create a user inside the toolbox container whose numerical user ID is UID")
-	initContainerCmd.MarkFlagRequired("uid")
+	err = initContainerCmd.MarkFlagRequired("uid")
+	if err != nil {
+		panic("Could not mark flag --uid as required")
+	}
 
 	flags.StringVar(&initContainerFlags.user,
 		"user",
 		"",
 		"Create a user inside the toolbox container whose login name is USER")
-	initContainerCmd.MarkFlagRequired("user")
+	err = initContainerCmd.MarkFlagRequired("user")
+	if err != nil {
+		panic("Could not mark flag --user as required")
+	}
 
 	initContainerCmd.SetHelpFunc(initContainerHelp)
 	rootCmd.AddCommand(initContainerCmd)
@@ -349,8 +361,6 @@ func initContainer(cmd *cobra.Command, args []string) error {
 			logrus.Warnf("Received an error from the file system watcher: %v", err)
 		}
 	}
-
-	return nil
 }
 
 func initContainerHelp(cmd *cobra.Command, args []string) {

src/cmd/run.go

@@ -364,8 +364,6 @@ func runCommandWithFallbacks(container string, command []string, emitEscapeSeque
 			return nil
 		}
 	}
-
-	panic("code should not be reached")
 }
 
 func runHelp(cmd *cobra.Command, args []string) {
@@ -476,12 +474,11 @@ func getEntryPointAndPID(container string) (string, int, error) {
 
 	var entryPointPIDInt int
 
-	switch entryPointPID.(type) {
+	switch entryPointPID := entryPointPID.(type) {
 	case float64:
-		entryPointPIDFloat := entryPointPID.(float64)
-		entryPointPIDInt = int(entryPointPIDFloat)
+		entryPointPIDInt = int(entryPointPID)
 	case int:
-		entryPointPIDInt = entryPointPID.(int)
+		entryPointPIDInt = entryPointPID
 	default:
 		return "", 0, fmt.Errorf("failed to inspect entry point PID of container %s", container)
 	}