fix broken error filtration

README.md

@@ -5,7 +5,6 @@ This library aims at providing idiomatic `systemctl` bindings for go developers,
 This tool tries to take guesswork out of arbitrarily shelling out to `systemctl` by providing a structured, thoroughly-tested wrapper for the `systemctl` functions most-likely to be used in a system program.
 
 If your system isn't running (or targeting another system running) `systemctl`, this library will be of little use to you.
-In fact, if `systemctl` isn't found in the `PATH`, this library will panic.
 
 ## What is systemctl
 

errors.go

@@ -21,7 +21,6 @@ var (
 	// Masked units can only be unmasked, but something else was attempted
 	// Unmask the unit before enabling or disabling it
 	ErrMasked = errors.New("unit masked")
-	// If this error occurs, the library isn't entirely useful, as it causes a panic
 	// Make sure systemctl is in the PATH before calling again
 	ErrNotInstalled = errors.New("systemctl not in $PATH")
 	// A unit was expected to be running but was found inactive

errors_test.go

@@ -2,6 +2,7 @@ package systemctl
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"reflect"
 	"runtime"
@@ -63,7 +64,7 @@ func TestErrorFuncs(t *testing.T) {
 					ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 					defer cancel()
 					err := f(ctx, tc.unit, tc.opts)
-					if err != tc.err {
+					if !errors.Is(err, tc.err) {
 						t.Errorf("error is %v, but should have been %v", err, tc.err)
 					}
 				})

go.mod

@@ -1,3 +1,3 @@
 module github.com/taigrr/systemctl
 
-go 1.17
+go 1.12

helpers.go

@@ -2,7 +2,9 @@ package systemctl
 
 import (
 	"context"
+	"errors"
 	"strconv"
+	"strings"
 	"time"
 
 	"github.com/taigrr/systemctl/properties"
@@ -52,3 +54,53 @@ func GetPID(ctx context.Context, unit string, opts Options) (int, error) {
 	}
 	return strconv.Atoi(value)
 }
+
+func GetMaskedUnits(ctx context.Context, opts Options) ([]string, error) {
+	args := []string{"list-unit-files", "--state=masked"}
+	if opts.UserMode {
+		args = append(args, "--user")
+	}
+	stdout, stderr, _, err := execute(ctx, args)
+	if err != nil {
+		return []string{}, errors.Join(err, filterErr(stderr))
+	}
+	lines := strings.Split(stdout, "\n")
+	units := []string{}
+	for _, line := range lines {
+		if !strings.Contains(line, "masked") {
+			continue
+		}
+		entry := strings.Split(line, " ")
+		if len(entry) < 3 {
+			continue
+		}
+		if entry[1] == "masked" {
+			unit := entry[0]
+			uName := strings.Split(unit, ".")
+			unit = uName[0]
+			units = append(units, unit)
+		}
+	}
+	return units, nil
+}
+
+// check if a service is masked
+func IsMasked(ctx context.Context, unit string, opts Options) (bool, error) {
+	units, err := GetMaskedUnits(ctx, opts)
+	if err != nil {
+		return false, err
+	}
+	for _, u := range units {
+		if u == unit {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+// check if a service is running
+// https://unix.stackexchange.com/a/396633
+func IsRunning(ctx context.Context, unit string, opts Options) (bool, error) {
+	status, err := Show(ctx, unit, properties.SubState, opts)
+	return status == "running", err
+}

helpers_test.go

@@ -2,6 +2,7 @@ package systemctl
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"syscall"
 	"testing"
@@ -58,13 +59,13 @@ func TestGetStartTime(t *testing.T) {
 			ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 			defer cancel()
 			_, err := GetStartTime(ctx, tc.unit, tc.opts)
-			if err != tc.err {
+			if !errors.Is(err, tc.err) {
 				t.Errorf("error is %v, but should have been %v", err, tc.err)
 			}
 		})
 	}
 	// Prove start time changes after a restart
-	t.Run(fmt.Sprintf("prove start time changes"), func(t *testing.T) {
+	t.Run("prove start time changes", func(t *testing.T) {
 		if userString != "root" && userString != "system" {
 			t.Skip("skipping superuser test while running as user")
 		}
@@ -93,12 +94,13 @@ func TestGetStartTime(t *testing.T) {
 }
 
 func TestGetNumRestarts(t *testing.T) {
-	testCases := []struct {
+	type testCase struct {
 		unit      string
 		err       error
 		opts      Options
 		runAsUser bool
-	}{
+	}
+	testCases := []testCase{
 		// Run these tests only as a user
 
 		// try nonexistant unit in user mode as user
@@ -118,6 +120,7 @@ func TestGetNumRestarts(t *testing.T) {
 		{"nginx", nil, Options{UserMode: false}, false},
 	}
 	for _, tc := range testCases {
+		func(tc testCase) {
 			t.Run(fmt.Sprintf("%s as %s", tc.unit, userString), func(t *testing.T) {
 				t.Parallel()
 				if (userString == "root" || userString == "system") && tc.runAsUser {
@@ -128,13 +131,14 @@ func TestGetNumRestarts(t *testing.T) {
 				ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 				defer cancel()
 				_, err := GetNumRestarts(ctx, tc.unit, tc.opts)
-			if err != tc.err {
+				if !errors.Is(err, tc.err) {
 					t.Errorf("error is %v, but should have been %v", err, tc.err)
 				}
 			})
+		}(tc)
 	}
 	// Prove restart count increases by one after a restart
-	t.Run(fmt.Sprintf("prove restart count increases by one after a restart"), func(t *testing.T) {
+	t.Run("prove restart count increases by one after a restart", func(t *testing.T) {
 		if testing.Short() {
 			t.Skip("skipping in short mode")
 		}
@@ -154,9 +158,9 @@ func TestGetNumRestarts(t *testing.T) {
 		}
 		syscall.Kill(pid, syscall.SIGKILL)
 		for {
-			running, err := IsActive(ctx, "nginx", Options{UserMode: false})
+			running, errIsActive := IsActive(ctx, "nginx", Options{UserMode: false})
-			if err != nil {
+			if errIsActive != nil {
-				t.Errorf("error asserting nginx is up: %v", err)
+				t.Errorf("error asserting nginx is up: %v", errIsActive)
 				break
 			} else if running {
 				break
@@ -173,12 +177,13 @@ func TestGetNumRestarts(t *testing.T) {
 }
 
 func TestGetMemoryUsage(t *testing.T) {
-	testCases := []struct {
+	type testCase struct {
 		unit      string
 		err       error
 		opts      Options
 		runAsUser bool
-	}{
+	}
+	testCases := []testCase{
 		// Run these tests only as a user
 
 		// try nonexistant unit in user mode as user
@@ -198,6 +203,7 @@ func TestGetMemoryUsage(t *testing.T) {
 		{"nginx", nil, Options{UserMode: false}, false},
 	}
 	for _, tc := range testCases {
+		func(tc testCase) {
 			t.Run(fmt.Sprintf("%s as %s", tc.unit, userString), func(t *testing.T) {
 				t.Parallel()
 				if (userString == "root" || userString == "system") && tc.runAsUser {
@@ -208,13 +214,14 @@ func TestGetMemoryUsage(t *testing.T) {
 				ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 				defer cancel()
 				_, err := GetMemoryUsage(ctx, tc.unit, tc.opts)
-			if err != tc.err {
+				if !errors.Is(err, tc.err) {
 					t.Errorf("error is %v, but should have been %v", err, tc.err)
 				}
 			})
+		}(tc)
 	}
 	// Prove memory usage values change across services
-	t.Run(fmt.Sprintf("prove memory usage values change across services"), func(t *testing.T) {
+	t.Run("prove memory usage values change across services", func(t *testing.T) {
 		ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 		defer cancel()
 		bytes, err := GetMemoryUsage(ctx, "nginx", Options{UserMode: false})
@@ -232,12 +239,14 @@ func TestGetMemoryUsage(t *testing.T) {
 }
 
 func TestGetPID(t *testing.T) {
-	testCases := []struct {
+	type testCase struct {
 		unit      string
 		err       error
 		opts      Options
 		runAsUser bool
-	}{
+	}
+
+	testCases := []testCase{
 		// Run these tests only as a user
 
 		// try nonexistant unit in user mode as user
@@ -257,6 +266,7 @@ func TestGetPID(t *testing.T) {
 		{"nginx", nil, Options{UserMode: false}, false},
 	}
 	for _, tc := range testCases {
+		func(tc testCase) {
 			t.Run(fmt.Sprintf("%s as %s", tc.unit, userString), func(t *testing.T) {
 				t.Parallel()
 				if (userString == "root" || userString == "system") && tc.runAsUser {
@@ -267,12 +277,13 @@ func TestGetPID(t *testing.T) {
 				ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 				defer cancel()
 				_, err := GetPID(ctx, tc.unit, tc.opts)
-			if err != tc.err {
+				if !errors.Is(err, tc.err) {
 					t.Errorf("error is %v, but should have been %v", err, tc.err)
 				}
 			})
+		}(tc)
 	}
-	t.Run(fmt.Sprintf("prove pid changes"), func(t *testing.T) {
+	t.Run("prove pid changes", func(t *testing.T) {
 		if testing.Short() {
 			t.Skip("skipping in short mode")
 		}

systemctl_test.go

@@ -2,6 +2,7 @@ package systemctl
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"os/user"
@@ -41,7 +42,6 @@ func TestMain(m *testing.M) {
 
 func TestDaemonReload(t *testing.T) {
 	testCases := []struct {
-		unit      string
 		err       error
 		opts      Options
 		runAsUser bool
@@ -49,22 +49,26 @@ func TestDaemonReload(t *testing.T) {
 		/* Run these tests only as a user */
 
 		// fail to reload system daemon as user
-		{"", ErrInsufficientPermissions, Options{UserMode: false}, true},
+		{ErrInsufficientPermissions, Options{UserMode: false}, true},
 		// reload user's scope daemon
-		{"", nil, Options{UserMode: true}, true},
+		{nil, Options{UserMode: true}, true},
 		/* End user tests*/
 
 		/* Run these tests only as a superuser */
 
 		// succeed to reload daemon
-		{"", nil, Options{UserMode: false}, false},
+		{nil, Options{UserMode: false}, false},
 		// fail to connect to user bus as system
-		{"", ErrBusFailure, Options{UserMode: true}, false},
+		{ErrBusFailure, Options{UserMode: true}, false},
 
 		/* End superuser tests*/
 	}
 	for _, tc := range testCases {
-		t.Run(fmt.Sprintf("%s as %s", tc.unit, userString), func(t *testing.T) {
+		mode := "user"
+		if tc.opts.UserMode == false {
+			mode = "system"
+		}
+		t.Run(fmt.Sprintf("DaemonReload as %s, %s mode", userString, mode), func(t *testing.T) {
 			if (userString == "root" || userString == "system") && tc.runAsUser {
 				t.Skip("skipping user test while running as superuser")
 			} else if (userString != "root" && userString != "system") && !tc.runAsUser {
@@ -73,7 +77,7 @@ func TestDaemonReload(t *testing.T) {
 			ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 			defer cancel()
 			err := DaemonReload(ctx, tc.opts)
-			if err != tc.err {
+			if !errors.Is(err, tc.err) {
 				t.Errorf("error is %v, but should have been %v", err, tc.err)
 			}
 		})
@@ -81,7 +85,6 @@ func TestDaemonReload(t *testing.T) {
 }
 
 func TestDisable(t *testing.T) {
-	t.Run(fmt.Sprintf(""), func(t *testing.T) {
 	if userString != "root" && userString != "system" {
 		t.Skip("skipping superuser test while running as user")
 	}
@@ -94,7 +97,7 @@ func TestDisable(t *testing.T) {
 		t.Errorf("Unable to mask %s", unit)
 	}
 	err = Disable(ctx, unit, Options{UserMode: false})
-		if err != ErrMasked {
+	if !errors.Is(err, ErrMasked) {
 		Unmask(ctx, unit, Options{UserMode: false})
 		t.Errorf("error is %v, but should have been %v", err, ErrMasked)
 	}
@@ -102,11 +105,9 @@ func TestDisable(t *testing.T) {
 	if err != nil {
 		t.Errorf("Unable to unmask %s", unit)
 	}
-	})
 }
 
 func TestReenable(t *testing.T) {
-	t.Run(fmt.Sprintf(""), func(t *testing.T) {
 	if userString != "root" && userString != "system" {
 		t.Skip("skipping superuser test while running as user")
 	}
@@ -119,7 +120,7 @@ func TestReenable(t *testing.T) {
 		t.Errorf("Unable to mask %s", unit)
 	}
 	err = Reenable(ctx, unit, Options{UserMode: false})
-		if err != ErrMasked {
+	if !errors.Is(err, ErrMasked) {
 		Unmask(ctx, unit, Options{UserMode: false})
 		t.Errorf("error is %v, but should have been %v", err, ErrMasked)
 	}
@@ -127,11 +128,9 @@ func TestReenable(t *testing.T) {
 	if err != nil {
 		t.Errorf("Unable to unmask %s", unit)
 	}
-	})
 }
 
 func TestEnable(t *testing.T) {
-	t.Run(fmt.Sprintf(""), func(t *testing.T) {
 	if userString != "root" && userString != "system" {
 		t.Skip("skipping superuser test while running as user")
 	}
@@ -144,7 +143,7 @@ func TestEnable(t *testing.T) {
 		t.Errorf("Unable to mask %s", unit)
 	}
 	err = Enable(ctx, unit, Options{UserMode: false})
-		if err != ErrMasked {
+	if !errors.Is(err, ErrMasked) {
 		Unmask(ctx, unit, Options{UserMode: false})
 		t.Errorf("error is %v, but should have been %v", err, ErrMasked)
 	}
@@ -152,7 +151,6 @@ func TestEnable(t *testing.T) {
 	if err != nil {
 		t.Errorf("Unable to unmask %s", unit)
 	}
-	})
 }
 
 func ExampleEnable() {
@@ -161,16 +159,16 @@ func ExampleEnable() {
 	defer cancel()
 
 	err := Enable(ctx, unit, Options{UserMode: true})
-	switch err {
+	switch {
-	case ErrMasked:
+	case errors.Is(err, ErrMasked):
 		fmt.Printf("%s is masked, unmask it before enabling\n", unit)
-	case ErrDoesNotExist:
+	case errors.Is(err, ErrDoesNotExist):
 		fmt.Printf("%s does not exist\n", unit)
-	case ErrInsufficientPermissions:
+	case errors.Is(err, ErrInsufficientPermissions):
 		fmt.Printf("permission to enable %s denied\n", unit)
-	case ErrBusFailure:
+	case errors.Is(err, ErrBusFailure):
 		fmt.Printf("Cannot communicate with the bus\n")
-	case nil:
+	case err == nil:
 		fmt.Printf("%s enabled successfully\n", unit)
 	default:
 		fmt.Printf("Error: %v", err)
@@ -179,7 +177,7 @@ func ExampleEnable() {
 
 func TestIsActive(t *testing.T) {
 	unit := "nginx"
-	t.Run(fmt.Sprintf("check active"), func(t *testing.T) {
+	t.Run("check active", func(t *testing.T) {
 		if testing.Short() {
 			t.Skip("skipping in short mode")
 		}
@@ -195,10 +193,10 @@ func TestIsActive(t *testing.T) {
 		time.Sleep(time.Second)
 		isActive, err := IsActive(ctx, unit, Options{UserMode: false})
 		if !isActive {
-			t.Errorf("IsActive didn't return true for %s", unit)
+			t.Errorf("IsActive didn't return true for %s: %v", unit, err)
 		}
 	})
-	t.Run(fmt.Sprintf("check masked"), func(t *testing.T) {
+	t.Run("check masked", func(t *testing.T) {
 		if userString != "root" && userString != "system" {
 			t.Skip("skipping superuser test while running as user")
 		}
@@ -214,7 +212,7 @@ func TestIsActive(t *testing.T) {
 		}
 		Unmask(ctx, unit, Options{UserMode: false})
 	})
-	t.Run(fmt.Sprintf("check masked"), func(t *testing.T) {
+	t.Run("check masked", func(t *testing.T) {
 		ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 		defer cancel()
 		_, err := IsActive(ctx, "nonexistant", Options{UserMode: false})
@@ -231,7 +229,7 @@ func TestIsEnabled(t *testing.T) {
 		userMode = true
 		unit = "syncthing"
 	}
-	t.Run(fmt.Sprintf("check enabled"), func(t *testing.T) {
+	t.Run("check enabled", func(t *testing.T) {
 		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
 		defer cancel()
 		err := Enable(ctx, unit, Options{UserMode: userMode})
@@ -240,10 +238,10 @@ func TestIsEnabled(t *testing.T) {
 		}
 		isEnabled, err := IsEnabled(ctx, unit, Options{UserMode: userMode})
 		if !isEnabled {
-			t.Errorf("IsEnabled didn't return true for %s", unit)
+			t.Errorf("IsEnabled didn't return true for %s: %v", unit, err)
 		}
 	})
-	t.Run(fmt.Sprintf("check disabled"), func(t *testing.T) {
+	t.Run("check disabled", func(t *testing.T) {
 		ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 		defer cancel()
 		err := Disable(ctx, unit, Options{UserMode: userMode})
@@ -259,7 +257,7 @@ func TestIsEnabled(t *testing.T) {
 		}
 		Enable(ctx, unit, Options{UserMode: false})
 	})
-	t.Run(fmt.Sprintf("check masked"), func(t *testing.T) {
+	t.Run("check masked", func(t *testing.T) {
 		ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 		defer cancel()
 		err := Mask(ctx, unit, Options{UserMode: userMode})
@@ -320,13 +318,13 @@ func TestMask(t *testing.T) {
 			ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 			defer cancel()
 			err := Mask(ctx, tc.unit, tc.opts)
-			if err != tc.err {
+			if !errors.Is(err, tc.err) {
 				t.Errorf("error is %v, but should have been %v", err, tc.err)
 			}
 			Unmask(ctx, tc.unit, tc.opts)
 		})
 	}
-	t.Run(fmt.Sprintf("test double masking existing"), func(t *testing.T) {
+	t.Run("test double masking existing", func(t *testing.T) {
 		unit := "nginx"
 		userMode := false
 		if userString != "root" && userString != "system" {
@@ -346,17 +344,15 @@ func TestMask(t *testing.T) {
 		}
 		Unmask(ctx, unit, opts)
 	})
-	t.Run(fmt.Sprintf("test double masking nonexisting"), func(t *testing.T) {
+	t.Run("test double masking nonexisting", func(t *testing.T) {
 		unit := "nonexistant"
-		userMode := false
+		userMode := userString != "root" && userString != "system"
-		if userString != "root" && userString != "system" {
+
-			userMode = true
-		}
 		opts := Options{UserMode: userMode}
 		ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 		defer cancel()
 		err := Mask(ctx, unit, opts)
-		if err != ErrDoesNotExist {
+		if !errors.Is(err, ErrDoesNotExist) {
 			t.Errorf("error on initial masking is %v, but should have been %v", err, ErrDoesNotExist)
 		}
 		err = Mask(ctx, unit, opts)
@@ -388,9 +384,9 @@ func TestRestart(t *testing.T) {
 	}
 	syscall.Kill(pid, syscall.SIGKILL)
 	for {
-		running, err := IsActive(ctx, unit, opts)
+		running, errIsActive := IsActive(ctx, unit, opts)
-		if err != nil {
+		if errIsActive != nil {
-			t.Errorf("error asserting %s is up: %v", unit, err)
+			t.Errorf("error asserting %s is up: %v", unit, errIsActive)
 			break
 		} else if running {
 			break
@@ -415,6 +411,7 @@ func TestShow(t *testing.T) {
 		UserMode: false,
 	}
 	for _, x := range properties.Properties {
+		func(x properties.Property) {
 			t.Run(fmt.Sprintf("show property %s", string(x)), func(t *testing.T) {
 				ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 				defer cancel()
@@ -424,6 +421,7 @@ func TestShow(t *testing.T) {
 					t.Errorf("error is %v, but should have been %v", err, nil)
 				}
 			})
+		}(x)
 	}
 }
 
@@ -551,13 +549,13 @@ func TestUnmask(t *testing.T) {
 			ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 			defer cancel()
 			err := Mask(ctx, tc.unit, tc.opts)
-			if err != tc.err {
+			if !errors.Is(err, tc.err) {
 				t.Errorf("error is %v, but should have been %v", err, tc.err)
 			}
 			Unmask(ctx, tc.unit, tc.opts)
 		})
 	}
-	t.Run(fmt.Sprintf("test double unmasking existing"), func(t *testing.T) {
+	t.Run("test double unmasking existing", func(t *testing.T) {
 		unit := "nginx"
 		userMode := false
 		if userString != "root" && userString != "system" {
@@ -577,12 +575,10 @@ func TestUnmask(t *testing.T) {
 		}
 		Unmask(ctx, unit, opts)
 	})
-	t.Run(fmt.Sprintf("test double unmasking nonexisting"), func(t *testing.T) {
+	t.Run("test double unmasking nonexisting", func(t *testing.T) {
 		unit := "nonexistant"
-		userMode := false
+		userMode := userString != "root" && userString != "system"
-		if userString != "root" && userString != "system" {
+
-			userMode = true
-		}
 		opts := Options{UserMode: userMode}
 		ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 		defer cancel()
@@ -592,7 +588,7 @@ func TestUnmask(t *testing.T) {
 			t.Errorf("error on initial unmasking is %v, but should have been %v", err, nil)
 		}
 		err = Unmask(ctx, unit, opts)
-		if err != ErrDoesNotExist {
+		if !errors.Is(err, ErrDoesNotExist) {
 			t.Errorf("error on second unmasking is %v, but should have been %v", err, ErrDoesNotExist)
 		}
 	})

util.go

@@ -3,10 +3,10 @@ package systemctl
 import (
 	"bytes"
 	"context"
+	"errors"
 	"fmt"
-	"log"
 	"os/exec"
-	"regexp"
+	"strings"
 )
 
 var systemctl string
@@ -14,12 +14,7 @@ var systemctl string
 const killed = 130
 
 func init() {
-	path, err := exec.LookPath("systemctl")
+	path, _ := exec.LookPath("systemctl")
-	if err != nil {
-		log.Printf("%v", ErrNotInstalled)
-		systemctl = ""
-		return
-	}
 	systemctl = path
 }
 
@@ -34,7 +29,7 @@ func execute(ctx context.Context, args []string) (string, string, int, error) {
 	)
 
 	if systemctl == "" {
-		panic(ErrNotInstalled)
+		return "", "", 1, ErrNotInstalled
 	}
 	cmd := exec.CommandContext(ctx, systemctl, args...)
 	cmd.Stdout = &stdout
@@ -56,32 +51,26 @@ func execute(ctx context.Context, args []string) (string, string, int, error) {
 }
 
 func filterErr(stderr string) error {
-	if matched, _ := regexp.MatchString(`does not exist`, stderr); matched {
+	switch {
-		return ErrDoesNotExist
+	case strings.Contains(stderr, `does not exist`):
-	}
+		return errors.Join(ErrDoesNotExist, fmt.Errorf("stderr: %s", stderr))
-	if matched, _ := regexp.MatchString(`not found.`, stderr); matched {
+	case strings.Contains(stderr, `not found.`):
-		return ErrDoesNotExist
+		return errors.Join(ErrDoesNotExist, fmt.Errorf("stderr: %s", stderr))
-	}
+	case strings.Contains(stderr, `not loaded.`):
-	if matched, _ := regexp.MatchString(`not loaded.`, stderr); matched {
+		return errors.Join(ErrUnitNotLoaded, fmt.Errorf("stderr: %s", stderr))
-		return ErrUnitNotLoaded
+	case strings.Contains(stderr, `No such file or directory`):
-	}
+		return errors.Join(ErrDoesNotExist, fmt.Errorf("stderr: %s", stderr))
-	if matched, _ := regexp.MatchString(`No such file or directory`, stderr); matched {
+	case strings.Contains(stderr, `Interactive authentication required`):
-		return ErrDoesNotExist
+		return errors.Join(ErrInsufficientPermissions, fmt.Errorf("stderr: %s", stderr))
-	}
+	case strings.Contains(stderr, `Access denied`):
-	if matched, _ := regexp.MatchString(`Interactive authentication required`, stderr); matched {
+		return errors.Join(ErrInsufficientPermissions, fmt.Errorf("stderr: %s", stderr))
-		return ErrInsufficientPermissions
+	case strings.Contains(stderr, `DBUS_SESSION_BUS_ADDRESS`):
-	}
+		return errors.Join(ErrBusFailure, fmt.Errorf("stderr: %s", stderr))
-	if matched, _ := regexp.MatchString(`Access denied`, stderr); matched {
+	case strings.Contains(stderr, `is masked`):
-		return ErrInsufficientPermissions
+		return errors.Join(ErrMasked, fmt.Errorf("stderr: %s", stderr))
-	}
+	case strings.Contains(stderr, `Failed`):
-	if matched, _ := regexp.MatchString(`DBUS_SESSION_BUS_ADDRESS`, stderr); matched {
+		return errors.Join(ErrUnspecified, fmt.Errorf("stderr: %s", stderr))
-		return ErrBusFailure
+	default:
-	}
-	if matched, _ := regexp.MatchString(`is masked`, stderr); matched {
-		return ErrMasked
-	}
-	if matched, _ := regexp.MatchString(`Failed`, stderr); matched {
-		return ErrUnspecified
-	}
 		return nil
 	}
+}