rename ErrRelaunchAttempt to ErrRelaunchSucceeded and fix elevated error handling

The old ErrRelaunchAttempt name was ambiguous — it reads as though the
relaunch attempt failed, when it actually signals success. Rename to
ErrRelaunchSucceeded and update comments at every call site to clarify
that this is not a real error but a sentinel indicating the elevated
child process completed the operation successfully.

Also fix a bug in WSL's launchElevate where a failed elevated process
was incorrectly wrapped with the sentinel, causing callers to treat the
failure as success and print "Machine init complete."

Signed-off-by: lstocchi <lstocchi@redhat.com>

Author: lstocchi

cmd/podman/machine/init.go

@@ -284,12 +284,13 @@ func initMachine(cmd *cobra.Command, args []string) error {
 
 	err = shim.Init(initOpts, machineProvider)
 	if err != nil {
-		// The installation is partially complete and podman should
-		// exit gracefully with no error and no success message.
-		// Examples:
-		// - a user has chosen to perform their own reboot
-		// - reexec for limited admin operations, returning to parent
-		if errors.Is(err, define.ErrRelaunchAttempt) {
+		// ErrRelaunchSucceeded is not a real error: it signals that
+		// an elevated child process completed init successfully.
+		// Exit gracefully with a success message.
+		//
+		// This can happen with WSL when installing the WSL features
+		// or with HyperV when adding entries to the Registry
+		if errors.Is(err, define.ErrRelaunchSucceeded) {
 			fmt.Println("Machine init complete")
 			if now {
 				fmt.Printf("Machine %q started successfully\n", initOpts.Name)

cmd/podman/machine/rm.go

@@ -63,11 +63,10 @@ func rm(_ *cobra.Command, args []string) error {
 	}
 
 	if err := shim.Remove(mc, vmProvider, destroyOptions); err != nil {
-		// The removal is partially complete and podman should
-		// exit gracefully with no error and no success message.
-		// Examples:
-		// - reexec for limited admin operations, returning to parent
-		if errors.Is(err, define.ErrRelaunchAttempt) {
+		// ErrRelaunchSucceeded is not a real error: it signals that
+		// an elevated child process completed the removal successfully.
+		// Exit gracefully.
+		if errors.Is(err, define.ErrRelaunchSucceeded) {
 			return nil
 		}
 		return err

pkg/machine/define/errors.go

@@ -6,10 +6,10 @@ import (
 )
 
 var (
-	ErrWrongState      = errors.New("VM in wrong state to perform action")
-	ErrNotImplemented  = errors.New("functionality not implemented")
-	ErrRelaunchAttempt = errors.New("stopping execution: command relaunched with --reexec flag for elevated privileges")
-	ErrRebootInitiated = errors.New("system reboot initiated")
+	ErrWrongState        = errors.New("VM in wrong state to perform action")
+	ErrNotImplemented    = errors.New("functionality not implemented")
+	ErrRelaunchSucceeded = errors.New("stopping execution: command relaunched with --reexec flag for elevated privileges succeeded")
+	ErrRebootInitiated   = errors.New("system reboot initiated")
 )
 
 type ErrVMAlreadyExists struct {

pkg/machine/hyperv/stubber.go

@@ -268,7 +268,7 @@ func launchElevate(message string) error {
 		windows.DumpOutputFile()
 		return fmt.Errorf("elevated process failed with error: %w", err)
 	}
-	return define.ErrRelaunchAttempt
+	return define.ErrRelaunchSucceeded
 }
 
 // createErrorLogCallback creates a callback function that logs errors to file when --reexec is detected

pkg/machine/shim/host.go

@@ -76,10 +76,11 @@ func Init(opts machineDefine.InitOptions, mp vmconfigs.VMProvider) error {
 
 	callbackFuncs := machine.CleanUp()
 	defer func() {
-		// Do not clean up on relaunch: the elevated child process
-		// completed init successfully and is using the resources
-		// (e.g. the disk image) that cleanup would remove.
-		if !errors.Is(err, machineDefine.ErrRelaunchAttempt) {
+		// ErrRelaunchSucceeded is not a real error: it signals that
+		// an elevated child process completed the operation successfully.
+		// Skip cleanup so we don't remove resources (e.g. the disk image)
+		// that the child process created and that are now in use.
+		if !errors.Is(err, machineDefine.ErrRelaunchSucceeded) {
 			callbackFuncs.CleanIfErr(&err)
 		}
 	}()

pkg/machine/wsl/machine.go

@@ -323,7 +323,7 @@ func attemptFeatureInstall(reExec, admin bool) error {
 		"If you prefer, you may abort now, and perform a manual installation using the \"wsl --install\" command."
 
 	if !reExec && winutil.MessageBox(message, "Podman Machine", false) != 1 {
-		return fmt.Errorf("the WSL installation aborted: %w", define.ErrRelaunchAttempt)
+		return fmt.Errorf("the WSL installation aborted: %w", define.ErrRelaunchSucceeded)
 	}
 
 	if !reExec && !admin {
@@ -341,16 +341,16 @@ func launchElevate(operation string) error {
 		if eerr, ok := err.(*winutil.ExitCodeError); ok {
 			if eerr.Code == ErrorSuccessRebootRequired {
 				fmt.Println("Reboot is required to continue installation, please reboot at your convenience")
-				return define.ErrRelaunchAttempt
+				return define.ErrRelaunchSucceeded
 			}
 		}
 
 		fmt.Fprintf(os.Stderr, "Elevated process failed with error: %v\n\n", err)
 		winutil.DumpOutputFile()
 		fmt.Fprintf(os.Stderr, wslInstallError, operation)
-		return fmt.Errorf("%w: %w", err, define.ErrRelaunchAttempt)
+		return fmt.Errorf("elevated process failed to %s: %w", operation, err)
 	}
-	return define.ErrRelaunchAttempt
+	return define.ErrRelaunchSucceeded
 }
 
 func installWsl() error {