Make IsEnabled match the documentation

errors.go

@@ -16,6 +16,8 @@ var (
 	// Running as superuser or adding the correct PolicyKit definitions can fix this
 	// See https://wiki.debian.org/PolicyKit for more information
 	ErrInsufficientPermissions = errors.New("insufficient permissions")
+	// Selected unit file resides outside of the unit file search path
+	ErrLinked = errors.New("unit file linked")
 	// Masked units can only be unmasked, but something else was attempted
 	// Unmask the unit before enabling or disabling it
 	ErrMasked = errors.New("unit masked")

systemctl.go

@@ -8,22 +8,54 @@ import (
 	"github.com/taigrr/systemctl/properties"
 )
 
-func IsFailed(ctx context.Context, unit string, opts Options) (bool, error) {
+// Reload systemd manager configuration.
-	var args = []string{"is-failed", "--system", unit}
+//
+// This will rerun all generators (see systemd. generator(7)), reload all unit
+// files, and recreate the entire dependency tree. While the daemon is being
+// reloaded, all sockets systemd listens on behalf of user configuration will
+// stay accessible.
+func DaemonReload(ctx context.Context, opts Options) error {
+	var args = []string{"daemon-reload", "--system"}
 	if opts.UserMode {
 		args[1] = "--user"
 	}
-	stdout, _, _, err := execute(ctx, args)
+	_, _, _, err := execute(ctx, args)
-	if matched, _ := regexp.MatchString(`inactive`, stdout); matched {
+	return err
-		return false, nil
-	} else if matched, _ := regexp.MatchString(`active`, stdout); matched {
-		return false, nil
-	} else if matched, _ := regexp.MatchString(`failed`, stdout); matched {
-		return true, nil
-	}
-	return false, err
 }
 
+// Disables one or more units.
+//
+// This removes all symlinks to the unit files backing the specified units from
+// the unit configuration directory, and hence undoes any changes made by
+// enable or link.
+func Disable(ctx context.Context, unit string, opts Options) error {
+	var args = []string{"disable", "--system", unit}
+	if opts.UserMode {
+		args[1] = "--user"
+	}
+	_, _, _, err := execute(ctx, args)
+	return err
+}
+
+// Enable one or more units or unit instances.
+//
+// This will create a set of symlinks, as encoded in the [Install] sections of
+// the indicated unit files. After the symlinks have been created, the system
+// manager configuration is reloaded (in a way equivalent to daemon-reload),
+// in order to ensure the changes are taken into account immediately.
+func Enable(ctx context.Context, unit string, opts Options) error {
+	var args = []string{"enable", "--system", unit}
+	if opts.UserMode {
+		args[1] = "--user"
+	}
+	_, _, _, err := execute(ctx, args)
+	return err
+}
+
+// Check whether any of the specified units are active (i.e. running).
+//
+// Returns true if the unit is active, false if inactive or failed.
+// Also returns false in an error case.
 func IsActive(ctx context.Context, unit string, opts Options) (bool, error) {
 	var args = []string{"is-active", "--system", unit}
 	if opts.UserMode {
@@ -41,30 +73,77 @@ func IsActive(ctx context.Context, unit string, opts Options) (bool, error) {
 	return false, err
 }
 
+// Checks whether any of the specified unit files are enabled (as with enable).
+//
+// Returns true if the unit is enabled, aliased, static, indirect, generated
+// or transient.
+//
+// Returns false if disabled. Also returns an error if linked, masked, or bad.
+//
+// See https://www.freedesktop.org/software/systemd/man/systemctl.html#is-enabled%20UNIT%E2%80%A6
+// for more information
 func IsEnabled(ctx context.Context, unit string, opts Options) (bool, error) {
 	var args = []string{"is-enabled", "--system", unit}
 	if opts.UserMode {
 		args[1] = "--user"
 	}
 	stdout, _, _, err := execute(ctx, args)
-	if matched, _ := regexp.MatchString(`enabled`, stdout); matched {
+	switch stdout {
+	case "enabled":
 		return true, nil
-	} else if matched, _ := regexp.MatchString(`disabled`, stdout); matched {
+	case "enabled-runtime":
-		return false, nil
+		return true, nil
-	} else if matched, _ := regexp.MatchString(`masked`, stdout); matched {
+	case "linked":
+		return false, ErrLinked
+	case "linked-runtime":
+		return false, ErrLinked
+	case "alias":
+		return true, nil
+	case "masked":
+		return false, ErrMasked
+	case "masked-runtime":
+		return false, ErrMasked
+	case "static":
+		return true, nil
+	case "indirect":
+		return true, nil
+	case "disabled":
 		return false, nil
+	case "generated":
+		return true, nil
+	case "transient":
+		return true, nil
 	}
-
+	if err != nil {
-	return false, err
+		return false, err
+	}
+	return false, ErrUnspecified
 }
 
-func Status(ctx context.Context, unit string, opts Options) (string, error) {
+// Check whether any of the specified units are in a "failed" state.
-	var args = []string{"status", "--system", unit}
+func IsFailed(ctx context.Context, unit string, opts Options) (bool, error) {
+	var args = []string{"is-failed", "--system", unit}
 	if opts.UserMode {
 		args[1] = "--user"
 	}
 	stdout, _, _, err := execute(ctx, args)
-	return stdout, err
+	if matched, _ := regexp.MatchString(`inactive`, stdout); matched {
+		return false, nil
+	} else if matched, _ := regexp.MatchString(`active`, stdout); matched {
+		return false, nil
+	} else if matched, _ := regexp.MatchString(`failed`, stdout); matched {
+		return true, nil
+	}
+	return false, err
+}
+
+func Mask(ctx context.Context, unit string, opts Options) error {
+	var args = []string{"mask", "--system", unit}
+	if opts.UserMode {
+		args[1] = "--user"
+	}
+	_, _, _, err := execute(ctx, args)
+	return err
 }
 
 func Restart(ctx context.Context, unit string, opts Options) error {
@@ -76,51 +155,6 @@ func Restart(ctx context.Context, unit string, opts Options) error {
 	return err
 }
 
-func Start(ctx context.Context, unit string, opts Options) error {
-	var args = []string{"start", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
-}
-
-func Stop(ctx context.Context, unit string, opts Options) error {
-	var args = []string{"stop", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
-}
-
-func Enable(ctx context.Context, unit string, opts Options) error {
-	var args = []string{"enable", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
-}
-
-func Disable(ctx context.Context, unit string, opts Options) error {
-	var args = []string{"disable", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
-}
-
-func DaemonReload(ctx context.Context, opts Options) error {
-	var args = []string{"daemon-reload", "--system"}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
-}
-
 func Show(ctx context.Context, unit string, property properties.Property, opts Options) (string, error) {
 	var args = []string{"show", "--system", unit, "--property", string(property)}
 	if opts.UserMode {
@@ -132,8 +166,26 @@ func Show(ctx context.Context, unit string, property properties.Property, opts O
 	return stdout, err
 }
 
-func Mask(ctx context.Context, unit string, opts Options) error {
+func Start(ctx context.Context, unit string, opts Options) error {
-	var args = []string{"mask", "--system", unit}
+	var args = []string{"start", "--system", unit}
+	if opts.UserMode {
+		args[1] = "--user"
+	}
+	_, _, _, err := execute(ctx, args)
+	return err
+}
+
+func Status(ctx context.Context, unit string, opts Options) (string, error) {
+	var args = []string{"status", "--system", unit}
+	if opts.UserMode {
+		args[1] = "--user"
+	}
+	stdout, _, _, err := execute(ctx, args)
+	return stdout, err
+}
+
+func Stop(ctx context.Context, unit string, opts Options) error {
+	var args = []string{"stop", "--system", unit}
 	if opts.UserMode {
 		args[1] = "--user"
 	}