feat: add optional variadic args to all commands

Allow callers to pass additional systemctl flags (e.g. --no-block,
--force) via variadic string args on every exported function.

This is backward-compatible: existing callers without extra args
continue to work unchanged.

Introduces a prepareArgs helper to centralize argument construction,
replacing the duplicated args/UserMode pattern across all functions.

Closes #2

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
 
@@ -33,7 +32,7 @@ In fact, if `systemctl` isn't found in the `PATH`, this library will panic.
 ## Helper functionality
 
 - [x] Get start time of a service (`ExecMainStartTimestamp`) as a `Time` type
-- [x] Get current memory in bytes (`MemoryCurrent`) an an int
+- [x] Get current memory in bytes (`MemoryCurrent`) as an int
 - [x] Get the PID of the main process (`MainPID`) as an int
 - [x] Get the restart count of a unit (`NRestarts`) as an int
 

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"
@@ -12,10 +13,10 @@ import (
 
 func TestErrorFuncs(t *testing.T) {
 	errFuncs := []func(ctx context.Context, unit string, opts Options) error{
-		Enable,
-		Disable,
-		Restart,
-		Start,
+		func(ctx context.Context, unit string, opts Options) error { return Enable(ctx, unit, opts) },
+		func(ctx context.Context, unit string, opts Options) error { return Disable(ctx, unit, opts) },
+		func(ctx context.Context, unit string, opts Options) error { return Restart(ctx, unit, opts) },
+		func(ctx context.Context, unit string, opts Options) error { return Start(ctx, unit, opts) },
 	}
 	errCases := []struct {
 		unit      string
@@ -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 1.26

helpers.go

@@ -2,7 +2,10 @@ package systemctl
 
 import (
 	"context"
+	"errors"
+	"os"
 	"strconv"
+	"strings"
 	"time"
 
 	"github.com/taigrr/systemctl/properties"
@@ -32,7 +35,7 @@ func GetNumRestarts(ctx context.Context, unit string, opts Options) (int, error)
 	return strconv.Atoi(value)
 }
 
-// Get current memory in bytes (`systemctl show [unit] --property MemoryCurrent`) an an int
+// Get current memory in bytes (`systemctl show [unit] --property MemoryCurrent`) as an int
 func GetMemoryUsage(ctx context.Context, unit string, opts Options) (int, error) {
 	value, err := Show(ctx, unit, properties.MemoryCurrent, opts)
 	if err != nil {
@@ -52,3 +55,118 @@ func GetPID(ctx context.Context, unit string, opts Options) (int, error) {
 	}
 	return strconv.Atoi(value)
 }
+
+// GetSocketsForServiceUnit returns the socket units associated with a given service unit.
+func GetSocketsForServiceUnit(ctx context.Context, unit string, opts Options) ([]string, error) {
+	args := []string{"list-sockets", "--all", "--no-legend", "--no-pager"}
+	if opts.UserMode {
+		args = append(args, "--user")
+	}
+	stdout, _, _, err := execute(ctx, args)
+	if err != nil {
+		return []string{}, err
+	}
+	lines := strings.Split(stdout, "\n")
+	sockets := []string{}
+	for _, line := range lines {
+		fields := strings.Fields(line)
+		if len(fields) < 3 {
+			continue
+		}
+		socketUnit := fields[1]
+		serviceUnit := fields[2]
+		if serviceUnit == unit+".service" {
+			sockets = append(sockets, socketUnit)
+		}
+	}
+	return sockets, nil
+}
+
+// GetUnits returns a list of all loaded units and their states.
+func GetUnits(ctx context.Context, opts Options) ([]Unit, error) {
+	args := []string{"list-units", "--all", "--no-legend", "--full", "--no-pager"}
+	if opts.UserMode {
+		args = append(args, "--user")
+	}
+	stdout, stderr, _, err := execute(ctx, args)
+	if err != nil {
+		return []Unit{}, errors.Join(err, filterErr(stderr))
+	}
+	lines := strings.Split(stdout, "\n")
+	units := []Unit{}
+	for _, line := range lines {
+		entry := strings.Fields(line)
+		if len(entry) < 4 {
+			continue
+		}
+		unit := Unit{
+			Name:        entry[0],
+			Load:        entry[1],
+			Active:      entry[2],
+			Sub:         entry[3],
+			Description: strings.Join(entry[4:], " "),
+		}
+		units = append(units, unit)
+	}
+	return units, nil
+}
+
+// GetMaskedUnits returns a list of all masked unit names.
+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
+}
+
+// IsSystemd checks if systemd is the current init system by reading /proc/1/comm.
+func IsSystemd() (bool, error) {
+	b, err := os.ReadFile("/proc/1/comm")
+	if err != nil {
+		return false, err
+	}
+	return strings.TrimSpace(string(b)) == "systemd", nil
+}
+
+// IsMasked checks if a unit 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
+}
+
+// IsRunning checks if a unit's sub-state is "running".
+// See https://unix.stackexchange.com/a/396633 for details.
+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})
-			if err != nil {
-				t.Errorf("error asserting nginx is up: %v", err)
+			running, errIsActive := IsActive(ctx, "nginx", Options{UserMode: false})
+			if errIsActive != nil {
+				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})
@@ -231,13 +238,63 @@ func TestGetMemoryUsage(t *testing.T) {
 	})
 }
 
+func TestGetUnits(t *testing.T) {
+	type testCase struct {
+		err       error
+		runAsUser bool
+		opts      Options
+	}
+	testCases := []testCase{{
+		// Run these tests only as a user
+		runAsUser: true,
+		opts:      Options{UserMode: true},
+		err:       nil,
+	}}
+	for _, tc := range testCases {
+		t.Run(fmt.Sprintf("as %s", userString), 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 {
+				t.Skip("skipping superuser test while running as user")
+			}
+			ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
+			defer cancel()
+			units, err := GetUnits(ctx, tc.opts)
+			if !errors.Is(err, tc.err) {
+				t.Errorf("error is %v, but should have been %v", err, tc.err)
+			}
+			if len(units) == 0 {
+				t.Errorf("Expected at least one unit, but got none")
+			}
+			unit := units[0]
+			if unit.Name == "" {
+				t.Errorf("Expected unit name to be non-empty, but got empty")
+			}
+			if unit.Load == "" {
+				t.Errorf("Expected unit load state to be non-empty, but got empty")
+			}
+			if unit.Active == "" {
+				t.Errorf("Expected unit active state to be non-empty, but got empty")
+			}
+			if unit.Sub == "" {
+				t.Errorf("Expected unit sub state to be non-empty, but got empty")
+			}
+			if unit.Description == "" {
+				t.Errorf("Expected unit description to be non-empty, but got empty")
+			}
+		})
+	}
+}
+
 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 +314,7 @@ 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 +325,13 @@ 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")
 		}

properties/properties.go

@@ -3,6 +3,7 @@ package properties
 type Property string
 
 const (
+	Accept                               Property = "Accept"
 	ActiveEnterTimestamp                 Property = "ActiveEnterTimestamp"
 	ActiveEnterTimestampMonotonic        Property = "ActiveEnterTimestampMonotonic"
 	ActiveExitTimestampMonotonic         Property = "ActiveExitTimestampMonotonic"
@@ -12,9 +13,13 @@ const (
 	AssertResult                         Property = "AssertResult"
 	AssertTimestamp                      Property = "AssertTimestamp"
 	AssertTimestampMonotonic             Property = "AssertTimestampMonotonic"
+	Backlog                              Property = "Backlog"
 	Before                               Property = "Before"
+	BindIPv6Only                         Property = "BindIPv6Only"
+	BindLogSockets                       Property = "BindLogSockets"
 	BlockIOAccounting                    Property = "BlockIOAccounting"
 	BlockIOWeight                        Property = "BlockIOWeight"
+	Broadcast                            Property = "Broadcast"
 	CPUAccounting                        Property = "CPUAccounting"
 	CPUAffinityFromNUMA                  Property = "CPUAffinityFromNUMA"
 	CPUQuotaPerSecUSec                   Property = "CPUQuotaPerSecUSec"
@@ -28,6 +33,7 @@ const (
 	CacheDirectoryMode                   Property = "CacheDirectoryMode"
 	CanFreeze                            Property = "CanFreeze"
 	CanIsolate                           Property = "CanIsolate"
+	CanLiveMount                         Property = "CanLiveMount"
 	CanReload                            Property = "CanReload"
 	CanStart                             Property = "CanStart"
 	CanStop                              Property = "CanStop"
@@ -40,17 +46,26 @@ const (
 	ConfigurationDirectoryMode           Property = "ConfigurationDirectoryMode"
 	Conflicts                            Property = "Conflicts"
 	ControlGroup                         Property = "ControlGroup"
+	ControlGroupId                       Property = "ControlGroupId"
 	ControlPID                           Property = "ControlPID"
 	CoredumpFilter                       Property = "CoredumpFilter"
+	CoredumpReceive                      Property = "CoredumpReceive"
+	DebugInvocation                      Property = "DebugInvocation"
 	DefaultDependencies                  Property = "DefaultDependencies"
 	DefaultMemoryLow                     Property = "DefaultMemoryLow"
 	DefaultMemoryMin                     Property = "DefaultMemoryMin"
+	DefaultStartupMemoryLow              Property = "DefaultStartupMemoryLow"
+	DeferAcceptUSec                      Property = "DeferAcceptUSec"
 	Delegate                             Property = "Delegate"
 	Description                          Property = "Description"
 	DevicePolicy                         Property = "DevicePolicy"
+	DirectoryMode                        Property = "DirectoryMode"
 	DynamicUser                          Property = "DynamicUser"
 	EffectiveCPUs                        Property = "EffectiveCPUs"
+	EffectiveMemoryHigh                  Property = "EffectiveMemoryHigh"
+	EffectiveMemoryMax                   Property = "EffectiveMemoryMax"
 	EffectiveMemoryNodes                 Property = "EffectiveMemoryNodes"
+	EffectiveTasksMax                    Property = "EffectiveTasksMax"
 	ExecMainCode                         Property = "ExecMainCode"
 	ExecMainExitTimestampMonotonic       Property = "ExecMainExitTimestampMonotonic"
 	ExecMainPID                          Property = "ExecMainPID"
@@ -61,10 +76,14 @@ const (
 	ExecReloadEx                         Property = "ExecReloadEx"
 	ExecStart                            Property = "ExecStart"
 	ExecStartEx                          Property = "ExecStartEx"
+	ExtensionImagePolicy                 Property = "ExtensionImagePolicy"
 	FailureAction                        Property = "FailureAction"
+	FileDescriptorName                   Property = "FileDescriptorName"
 	FileDescriptorStoreMax               Property = "FileDescriptorStoreMax"
 	FinalKillSignal                      Property = "FinalKillSignal"
+	FlushPending                         Property = "FlushPending"
 	FragmentPath                         Property = "FragmentPath"
+	FreeBind                             Property = "FreeBind"
 	FreezerState                         Property = "FreezerState"
 	GID                                  Property = "GID"
 	GuessMainPID                         Property = "GuessMainPID"
@@ -81,6 +100,8 @@ const (
 	IPEgressPackets                      Property = "IPEgressPackets"
 	IPIngressBytes                       Property = "IPIngressBytes"
 	IPIngressPackets                     Property = "IPIngressPackets"
+	IPTOS                                Property = "IPTOS"
+	IPTTL                                Property = "IPTTL"
 	Id                                   Property = "Id"
 	IgnoreOnIsolate                      Property = "IgnoreOnIsolate"
 	IgnoreSIGPIPE                        Property = "IgnoreSIGPIPE"
@@ -91,6 +112,10 @@ const (
 	JobRunningTimeoutUSec                Property = "JobRunningTimeoutUSec"
 	JobTimeoutAction                     Property = "JobTimeoutAction"
 	JobTimeoutUSec                       Property = "JobTimeoutUSec"
+	KeepAlive                            Property = "KeepAlive"
+	KeepAliveIntervalUSec                Property = "KeepAliveIntervalUSec"
+	KeepAliveProbes                      Property = "KeepAliveProbes"
+	KeepAliveTimeUSec                    Property = "KeepAliveTimeUSec"
 	KeyringMode                          Property = "KeyringMode"
 	KillMode                             Property = "KillMode"
 	KillSignal                           Property = "KillSignal"
@@ -126,6 +151,7 @@ const (
 	LimitSIGPENDINGSoft                  Property = "LimitSIGPENDINGSoft"
 	LimitSTACK                           Property = "LimitSTACK"
 	LimitSTACKSoft                       Property = "LimitSTACKSoft"
+	Listen                               Property = "Listen"
 	LoadState                            Property = "LoadState"
 	LockPersonality                      Property = "LockPersonality"
 	LogLevelMax                          Property = "LogLevelMax"
@@ -134,42 +160,76 @@ const (
 	LogsDirectoryMode                    Property = "LogsDirectoryMode"
 	MainPID                              Property = "MainPID"
 	ManagedOOMMemoryPressure             Property = "ManagedOOMMemoryPressure"
+	ManagedOOMMemoryPressureDurationUSec Property = "ManagedOOMMemoryPressureDurationUSec"
 	ManagedOOMMemoryPressureLimit        Property = "ManagedOOMMemoryPressureLimit"
 	ManagedOOMPreference                 Property = "ManagedOOMPreference"
 	ManagedOOMSwap                       Property = "ManagedOOMSwap"
+	Mark                                 Property = "Mark"
+	MaxConnections                       Property = "MaxConnections"
+	MaxConnectionsPerSource              Property = "MaxConnectionsPerSource"
 	MemoryAccounting                     Property = "MemoryAccounting"
+	MemoryAvailable                      Property = "MemoryAvailable"
 	MemoryCurrent                        Property = "MemoryCurrent"
 	MemoryDenyWriteExecute               Property = "MemoryDenyWriteExecute"
 	MemoryHigh                           Property = "MemoryHigh"
+	MemoryKSM                            Property = "MemoryKSM"
 	MemoryLimit                          Property = "MemoryLimit"
 	MemoryLow                            Property = "MemoryLow"
 	MemoryMax                            Property = "MemoryMax"
 	MemoryMin                            Property = "MemoryMin"
+	MemoryPeak                           Property = "MemoryPeak"
+	MemoryPressureThresholdUSec          Property = "MemoryPressureThresholdUSec"
+	MemoryPressureWatch                  Property = "MemoryPressureWatch"
+	MemorySwapCurrent                    Property = "MemorySwapCurrent"
 	MemorySwapMax                        Property = "MemorySwapMax"
+	MemorySwapPeak                       Property = "MemorySwapPeak"
+	MemoryZSwapCurrent                   Property = "MemoryZSwapCurrent"
+	MemoryZSwapMax                       Property = "MemoryZSwapMax"
+	MemoryZSwapWriteback                 Property = "MemoryZSwapWriteback"
+	MessageQueueMaxMessages              Property = "MessageQueueMaxMessages"
+	MessageQueueMessageSize              Property = "MessageQueueMessageSize"
 	MountAPIVFS                          Property = "MountAPIVFS"
+	MountImagePolicy                     Property = "MountImagePolicy"
+	NAccepted                            Property = "NAccepted"
+	NConnections                         Property = "NConnections"
 	NFileDescriptorStore                 Property = "NFileDescriptorStore"
+	NRefused                             Property = "NRefused"
 	NRestarts                            Property = "NRestarts"
 	NUMAPolicy                           Property = "NUMAPolicy"
 	Names                                Property = "Names"
 	NeedDaemonReload                     Property = "NeedDaemonReload"
 	Nice                                 Property = "Nice"
+	NoDelay                              Property = "NoDelay"
 	NoNewPrivileges                      Property = "NoNewPrivileges"
 	NonBlocking                          Property = "NonBlocking"
 	NotifyAccess                         Property = "NotifyAccess"
 	OOMPolicy                            Property = "OOMPolicy"
 	OOMScoreAdjust                       Property = "OOMScoreAdjust"
 	OnFailureJobMode                     Property = "OnFailureJobMode"
+	OnSuccessJobMode                     Property = "OnSuccessJobMode"
 	PIDFile                              Property = "PIDFile"
+	PassCredentials                      Property = "PassCredentials"
+	PassFileDescriptorsToExec            Property = "PassFileDescriptorsToExec"
+	PassPacketInfo                       Property = "PassPacketInfo"
+	PassSecurity                         Property = "PassSecurity"
 	Perpetual                            Property = "Perpetual"
+	PipeSize                             Property = "PipeSize"
+	PollLimitBurst                       Property = "PollLimitBurst"
+	PollLimitIntervalUSec                Property = "PollLimitIntervalUSec"
+	Priority                             Property = "Priority"
 	PrivateDevices                       Property = "PrivateDevices"
 	PrivateIPC                           Property = "PrivateIPC"
 	PrivateMounts                        Property = "PrivateMounts"
 	PrivateNetwork                       Property = "PrivateNetwork"
+	PrivatePIDs                          Property = "PrivatePIDs"
 	PrivateTmp                           Property = "PrivateTmp"
+	PrivateTmpEx                         Property = "PrivateTmpEx"
 	PrivateUsers                         Property = "PrivateUsers"
+	PrivateUsersEx                       Property = "PrivateUsersEx"
 	ProcSubset                           Property = "ProcSubset"
 	ProtectClock                         Property = "ProtectClock"
 	ProtectControlGroups                 Property = "ProtectControlGroups"
+	ProtectControlGroupsEx               Property = "ProtectControlGroupsEx"
 	ProtectHome                          Property = "ProtectHome"
 	ProtectHostname                      Property = "ProtectHostname"
 	ProtectKernelLogs                    Property = "ProtectKernelLogs"
@@ -177,12 +237,16 @@ const (
 	ProtectKernelTunables                Property = "ProtectKernelTunables"
 	ProtectProc                          Property = "ProtectProc"
 	ProtectSystem                        Property = "ProtectSystem"
+	ReceiveBuffer                        Property = "ReceiveBuffer"
 	RefuseManualStart                    Property = "RefuseManualStart"
 	RefuseManualStop                     Property = "RefuseManualStop"
 	ReloadResult                         Property = "ReloadResult"
 	RemainAfterExit                      Property = "RemainAfterExit"
 	RemoveIPC                            Property = "RemoveIPC"
+	RemoveOnStop                         Property = "RemoveOnStop"
+	RequiredBy                           Property = "RequiredBy"
 	Requires                             Property = "Requires"
+	RequiresMountsFor                    Property = "RequiresMountsFor"
 	Restart                              Property = "Restart"
 	RestartKillSignal                    Property = "RestartKillSignal"
 	RestartUSec                          Property = "RestartUSec"
@@ -190,15 +254,22 @@ const (
 	RestrictRealtime                     Property = "RestrictRealtime"
 	RestrictSUIDSGID                     Property = "RestrictSUIDSGID"
 	Result                               Property = "Result"
+	ReusePort                            Property = "ReusePort"
 	RootDirectoryStartOnly               Property = "RootDirectoryStartOnly"
+	RootEphemeral                        Property = "RootEphemeral"
+	RootImagePolicy                      Property = "RootImagePolicy"
 	RuntimeDirectoryMode                 Property = "RuntimeDirectoryMode"
 	RuntimeDirectoryPreserve             Property = "RuntimeDirectoryPreserve"
 	RuntimeMaxUSec                       Property = "RuntimeMaxUSec"
 	SameProcessGroup                     Property = "SameProcessGroup"
 	SecureBits                           Property = "SecureBits"
+	SendBuffer                           Property = "SendBuffer"
 	SendSIGHUP                           Property = "SendSIGHUP"
 	SendSIGKILL                          Property = "SendSIGKILL"
+	SetLoginEnvironment                  Property = "SetLoginEnvironment"
 	Slice                                Property = "Slice"
+	SocketMode                           Property = "SocketMode"
+	SocketProtocol                       Property = "SocketProtocol"
 	StandardError                        Property = "StandardError"
 	StandardInput                        Property = "StandardInput"
 	StandardOutput                       Property = "StandardOutput"
@@ -209,6 +280,11 @@ const (
 	StartupCPUShares                     Property = "StartupCPUShares"
 	StartupCPUWeight                     Property = "StartupCPUWeight"
 	StartupIOWeight                      Property = "StartupIOWeight"
+	StartupMemoryHigh                    Property = "StartupMemoryHigh"
+	StartupMemoryLow                     Property = "StartupMemoryLow"
+	StartupMemoryMax                     Property = "StartupMemoryMax"
+	StartupMemorySwapMax                 Property = "StartupMemorySwapMax"
+	StartupMemoryZSwapMax                Property = "StartupMemoryZSwapMax"
 	StateChangeTimestamp                 Property = "StateChangeTimestamp"
 	StateChangeTimestampMonotonic        Property = "StateChangeTimestampMonotonic"
 	StateDirectoryMode                   Property = "StateDirectoryMode"
@@ -216,6 +292,7 @@ const (
 	StopWhenUnneeded                     Property = "StopWhenUnneeded"
 	SubState                             Property = "SubState"
 	SuccessAction                        Property = "SuccessAction"
+	SurviveFinalKillSignal               Property = "SurviveFinalKillSignal"
 	SyslogFacility                       Property = "SyslogFacility"
 	SyslogLevel                          Property = "SyslogLevel"
 	SyslogLevelPrefix                    Property = "SyslogLevelPrefix"
@@ -233,8 +310,14 @@ const (
 	TimeoutStartUSec                     Property = "TimeoutStartUSec"
 	TimeoutStopFailureMode               Property = "TimeoutStopFailureMode"
 	TimeoutStopUSec                      Property = "TimeoutStopUSec"
+	TimeoutUSec                          Property = "TimeoutUSec"
 	TimerSlackNSec                       Property = "TimerSlackNSec"
+	Timestamping                         Property = "Timestamping"
 	Transient                            Property = "Transient"
+	Transparent                          Property = "Transparent"
+	TriggerLimitBurst                    Property = "TriggerLimitBurst"
+	TriggerLimitIntervalUSec             Property = "TriggerLimitIntervalUSec"
+	Triggers                             Property = "Triggers"
 	Type                                 Property = "Type"
 	UID                                  Property = "UID"
 	UMask                                Property = "UMask"
@@ -245,4 +328,5 @@ const (
 	WatchdogSignal                       Property = "WatchdogSignal"
 	WatchdogTimestampMonotonic           Property = "WatchdogTimestampMonotonic"
 	WatchdogUSec                         Property = "WatchdogUSec"
+	Writable                             Property = "Writable"
 )

properties/properties_list.go

@@ -1,6 +1,7 @@
 package properties
 
 var Properties = []Property{
+	Accept,
 	ActiveEnterTimestamp,
 	ActiveEnterTimestampMonotonic,
 	ActiveExitTimestampMonotonic,
@@ -10,9 +11,13 @@ var Properties = []Property{
 	AssertResult,
 	AssertTimestamp,
 	AssertTimestampMonotonic,
+	Backlog,
 	Before,
+	BindIPv6Only,
+	BindLogSockets,
 	BlockIOAccounting,
 	BlockIOWeight,
+	Broadcast,
 	CPUAccounting,
 	CPUAffinityFromNUMA,
 	CPUQuotaPerSecUSec,
@@ -26,6 +31,7 @@ var Properties = []Property{
 	CacheDirectoryMode,
 	CanFreeze,
 	CanIsolate,
+	CanLiveMount,
 	CanReload,
 	CanStart,
 	CanStop,
@@ -38,17 +44,26 @@ var Properties = []Property{
 	ConfigurationDirectoryMode,
 	Conflicts,
 	ControlGroup,
+	ControlGroupId,
 	ControlPID,
 	CoredumpFilter,
+	CoredumpReceive,
+	DebugInvocation,
 	DefaultDependencies,
 	DefaultMemoryLow,
 	DefaultMemoryMin,
+	DefaultStartupMemoryLow,
+	DeferAcceptUSec,
 	Delegate,
 	Description,
 	DevicePolicy,
+	DirectoryMode,
 	DynamicUser,
 	EffectiveCPUs,
+	EffectiveMemoryHigh,
+	EffectiveMemoryMax,
 	EffectiveMemoryNodes,
+	EffectiveTasksMax,
 	ExecMainCode,
 	ExecMainExitTimestampMonotonic,
 	ExecMainPID,
@@ -59,10 +74,14 @@ var Properties = []Property{
 	ExecReloadEx,
 	ExecStart,
 	ExecStartEx,
+	ExtensionImagePolicy,
 	FailureAction,
+	FileDescriptorName,
 	FileDescriptorStoreMax,
 	FinalKillSignal,
+	FlushPending,
 	FragmentPath,
+	FreeBind,
 	FreezerState,
 	GID,
 	GuessMainPID,
@@ -79,6 +98,8 @@ var Properties = []Property{
 	IPEgressPackets,
 	IPIngressBytes,
 	IPIngressPackets,
+	IPTOS,
+	IPTTL,
 	Id,
 	IgnoreOnIsolate,
 	IgnoreSIGPIPE,
@@ -89,6 +110,10 @@ var Properties = []Property{
 	JobRunningTimeoutUSec,
 	JobTimeoutAction,
 	JobTimeoutUSec,
+	KeepAlive,
+	KeepAliveIntervalUSec,
+	KeepAliveProbes,
+	KeepAliveTimeUSec,
 	KeyringMode,
 	KillMode,
 	KillSignal,
@@ -124,6 +149,7 @@ var Properties = []Property{
 	LimitSIGPENDINGSoft,
 	LimitSTACK,
 	LimitSTACKSoft,
+	Listen,
 	LoadState,
 	LockPersonality,
 	LogLevelMax,
@@ -132,42 +158,76 @@ var Properties = []Property{
 	LogsDirectoryMode,
 	MainPID,
 	ManagedOOMMemoryPressure,
+	ManagedOOMMemoryPressureDurationUSec,
 	ManagedOOMMemoryPressureLimit,
 	ManagedOOMPreference,
 	ManagedOOMSwap,
+	Mark,
+	MaxConnections,
+	MaxConnectionsPerSource,
 	MemoryAccounting,
+	MemoryAvailable,
 	MemoryCurrent,
 	MemoryDenyWriteExecute,
 	MemoryHigh,
+	MemoryKSM,
 	MemoryLimit,
 	MemoryLow,
 	MemoryMax,
 	MemoryMin,
+	MemoryPeak,
+	MemoryPressureThresholdUSec,
+	MemoryPressureWatch,
+	MemorySwapCurrent,
 	MemorySwapMax,
+	MemorySwapPeak,
+	MemoryZSwapCurrent,
+	MemoryZSwapMax,
+	MemoryZSwapWriteback,
+	MessageQueueMaxMessages,
+	MessageQueueMessageSize,
 	MountAPIVFS,
+	MountImagePolicy,
+	NAccepted,
+	NConnections,
 	NFileDescriptorStore,
+	NRefused,
 	NRestarts,
 	NUMAPolicy,
 	Names,
 	NeedDaemonReload,
 	Nice,
+	NoDelay,
 	NoNewPrivileges,
 	NonBlocking,
 	NotifyAccess,
 	OOMPolicy,
 	OOMScoreAdjust,
 	OnFailureJobMode,
+	OnSuccessJobMode,
 	PIDFile,
+	PassCredentials,
+	PassFileDescriptorsToExec,
+	PassPacketInfo,
+	PassSecurity,
 	Perpetual,
+	PipeSize,
+	PollLimitBurst,
+	PollLimitIntervalUSec,
+	Priority,
 	PrivateDevices,
 	PrivateIPC,
 	PrivateMounts,
 	PrivateNetwork,
+	PrivatePIDs,
 	PrivateTmp,
+	PrivateTmpEx,
 	PrivateUsers,
+	PrivateUsersEx,
 	ProcSubset,
 	ProtectClock,
 	ProtectControlGroups,
+	ProtectControlGroupsEx,
 	ProtectHome,
 	ProtectHostname,
 	ProtectKernelLogs,
@@ -175,12 +235,16 @@ var Properties = []Property{
 	ProtectKernelTunables,
 	ProtectProc,
 	ProtectSystem,
+	ReceiveBuffer,
 	RefuseManualStart,
 	RefuseManualStop,
 	ReloadResult,
 	RemainAfterExit,
 	RemoveIPC,
+	RemoveOnStop,
+	RequiredBy,
 	Requires,
+	RequiresMountsFor,
 	Restart,
 	RestartKillSignal,
 	RestartUSec,
@@ -188,15 +252,22 @@ var Properties = []Property{
 	RestrictRealtime,
 	RestrictSUIDSGID,
 	Result,
+	ReusePort,
 	RootDirectoryStartOnly,
+	RootEphemeral,
+	RootImagePolicy,
 	RuntimeDirectoryMode,
 	RuntimeDirectoryPreserve,
 	RuntimeMaxUSec,
 	SameProcessGroup,
 	SecureBits,
+	SendBuffer,
 	SendSIGHUP,
 	SendSIGKILL,
+	SetLoginEnvironment,
 	Slice,
+	SocketMode,
+	SocketProtocol,
 	StandardError,
 	StandardInput,
 	StandardOutput,
@@ -207,6 +278,11 @@ var Properties = []Property{
 	StartupCPUShares,
 	StartupCPUWeight,
 	StartupIOWeight,
+	StartupMemoryHigh,
+	StartupMemoryLow,
+	StartupMemoryMax,
+	StartupMemorySwapMax,
+	StartupMemoryZSwapMax,
 	StateChangeTimestamp,
 	StateChangeTimestampMonotonic,
 	StateDirectoryMode,
@@ -214,6 +290,7 @@ var Properties = []Property{
 	StopWhenUnneeded,
 	SubState,
 	SuccessAction,
+	SurviveFinalKillSignal,
 	SyslogFacility,
 	SyslogLevel,
 	SyslogLevelPrefix,
@@ -231,8 +308,14 @@ var Properties = []Property{
 	TimeoutStartUSec,
 	TimeoutStopFailureMode,
 	TimeoutStopUSec,
+	TimeoutUSec,
 	TimerSlackNSec,
+	Timestamping,
 	Transient,
+	Transparent,
+	TriggerLimitBurst,
+	TriggerLimitIntervalUSec,
+	Triggers,
 	Type,
 	UID,
 	UMask,
@@ -243,4 +326,5 @@ var Properties = []Property{
 	WatchdogSignal,
 	WatchdogTimestampMonotonic,
 	WatchdogUSec,
+	Writable,
 }

structs.go

@@ -1,5 +1,42 @@
 package systemctl
 
+import "strings"
+
 type Options struct {
 	UserMode bool
 }
+
+type Unit struct {
+	Name        string
+	Load        string
+	Active      string
+	Sub         string
+	Description string
+}
+
+// UnitTypes contains all valid systemd unit type suffixes.
+var UnitTypes = []string{
+	"automount",
+	"device",
+	"mount",
+	"path",
+	"scope",
+	"service",
+	"slice",
+	"snapshot",
+	"socket",
+	"swap",
+	"target",
+	"timer",
+}
+
+// HasValidUnitSuffix checks whether the given unit name ends with a valid
+// systemd unit type suffix (e.g. ".service", ".timer").
+func HasValidUnitSuffix(unit string) bool {
+	for _, t := range UnitTypes {
+		if strings.HasSuffix(unit, "."+t) {
+			return true
+		}
+	}
+	return false
+}

systemctl.go

@@ -2,8 +2,6 @@ package systemctl
 
 import (
 	"context"
-	"regexp"
-	"strings"
 
 	"github.com/taigrr/systemctl/properties"
 )
@@ -14,13 +12,10 @@ import (
 // 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 {
-	args := []string{"daemon-reload", "--system"}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
+//
+// Any additional arguments are passed directly to the systemctl command.
+func DaemonReload(ctx context.Context, opts Options, args ...string) error {
+	return daemonReload(ctx, opts, args...)
 }
 
 // Reenables one or more units.
@@ -28,13 +23,10 @@ func DaemonReload(ctx context.Context, opts Options) error {
 // This removes all symlinks to the unit files backing the specified units from
 // the unit configuration directory, then recreates the symlink to the unit again,
 // atomically. Can be used to change the symlink target.
-func Reenable(ctx context.Context, unit string, opts Options) error {
-	args := []string{"reenable", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
+//
+// Any additional arguments are passed directly to the systemctl command.
+func Reenable(ctx context.Context, unit string, opts Options, args ...string) error {
+	return reenable(ctx, unit, opts, args...)
 }
 
 // Disables one or more units.
@@ -42,13 +34,10 @@ func Reenable(ctx context.Context, unit string, opts Options) error {
 // 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 {
-	args := []string{"disable", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
+//
+// Any additional arguments are passed directly to the systemctl command.
+func Disable(ctx context.Context, unit string, opts Options, args ...string) error {
+	return disable(ctx, unit, opts, args...)
 }
 
 // Enable one or more units or unit instances.
@@ -57,38 +46,20 @@ func Disable(ctx context.Context, unit string, opts Options) error {
 // 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 {
-	args := []string{"enable", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
+//
+// Any additional arguments are passed directly to the systemctl command.
+func Enable(ctx context.Context, unit string, opts Options, args ...string) error {
+	return enable(ctx, unit, opts, args...)
 }
 
 // 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) {
-	args := []string{"is-active", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	stdout, _, _, err := execute(ctx, args)
-	stdout = strings.TrimSuffix(stdout, "\n")
-	switch stdout {
-	case "inactive":
-		return false, nil
-	case "active":
-		return true, nil
-	case "failed":
-		return false, nil
-	case "activating":
-		return false, nil
-	default:
-		return false, err
-	}
+//
+// Any additional arguments are passed directly to the systemctl command.
+func IsActive(ctx context.Context, unit string, opts Options, args ...string) (bool, error) {
+	return isActive(ctx, unit, opts, args...)
 }
 
 // Checks whether any of the specified unit files are enabled (as with enable).
@@ -100,60 +71,17 @@ func IsActive(ctx context.Context, unit string, opts Options) (bool, error) {
 //
 // 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) {
-	args := []string{"is-enabled", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	stdout, _, _, err := execute(ctx, args)
-	stdout = strings.TrimSuffix(stdout, "\n")
-	switch stdout {
-	case "enabled":
-		return true, nil
-	case "enabled-runtime":
-		return true, nil
-	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, ErrUnspecified
+//
+// Any additional arguments are passed directly to the systemctl command.
+func IsEnabled(ctx context.Context, unit string, opts Options, args ...string) (bool, error) {
+	return isEnabled(ctx, unit, opts, args...)
 }
 
 // Check whether any of the specified units are in a "failed" state.
-func IsFailed(ctx context.Context, unit string, opts Options) (bool, error) {
-	args := []string{"is-failed", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	stdout, _, _, err := execute(ctx, args)
-	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
+//
+// Any additional arguments are passed directly to the systemctl command.
+func IsFailed(ctx context.Context, unit string, opts Options, args ...string) (bool, error) {
+	return isFailed(ctx, unit, opts, args...)
 }
 
 // Mask one or more units, as specified on the command line. This will link
@@ -162,71 +90,51 @@ func IsFailed(ctx context.Context, unit string, opts Options) (bool, error) {
 // Notably, Mask may return ErrDoesNotExist if a unit doesn't exist, but it will
 // continue masking anyway. Calling Mask on a non-existing masked unit does not
 // return an error. Similarly, see Unmask.
-func Mask(ctx context.Context, unit string, opts Options) error {
-	args := []string{"mask", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
+//
+// Any additional arguments are passed directly to the systemctl command.
+func Mask(ctx context.Context, unit string, opts Options, args ...string) error {
+	return mask(ctx, unit, opts, args...)
 }
 
 // Stop and then start one or more units specified on the command line.
 // If the units are not running yet, they will be started.
-func Restart(ctx context.Context, unit string, opts Options) error {
-	args := []string{"restart", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
+//
+// Any additional arguments are passed directly to the systemctl command.
+func Restart(ctx context.Context, unit string, opts Options, args ...string) error {
+	return restart(ctx, unit, opts, args...)
 }
 
 // Show a selected property of a unit. Accepted properties are predefined in the
 // properties subpackage to guarantee properties are valid and assist code-completion.
-func Show(ctx context.Context, unit string, property properties.Property, opts Options) (string, error) {
-	args := []string{"show", "--system", unit, "--property", string(property)}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	stdout, _, _, err := execute(ctx, args)
-	stdout = strings.TrimPrefix(stdout, string(property)+"=")
-	stdout = strings.TrimSuffix(stdout, "\n")
-	return stdout, err
+//
+// Any additional arguments are passed directly to the systemctl command.
+func Show(ctx context.Context, unit string, property properties.Property, opts Options, args ...string) (string, error) {
+	return show(ctx, unit, property, opts, args...)
 }
 
 // Start (activate) a given unit
-func Start(ctx context.Context, unit string, opts Options) error {
-	args := []string{"start", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
+//
+// Any additional arguments are passed directly to the systemctl command.
+func Start(ctx context.Context, unit string, opts Options, args ...string) error {
+	return start(ctx, unit, opts, args...)
 }
 
 // Get back the status string which would be returned by running
 // `systemctl status [unit]`.
 //
-// Generally, it makes more sense to programatically retrieve the properties
+// Generally, it makes more sense to programmatically retrieve the properties
 // using Show, but this command is provided for the sake of completeness
-func Status(ctx context.Context, unit string, opts Options) (string, error) {
-	args := []string{"status", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	stdout, _, _, err := execute(ctx, args)
-	return stdout, err
+//
+// Any additional arguments are passed directly to the systemctl command.
+func Status(ctx context.Context, unit string, opts Options, args ...string) (string, error) {
+	return status(ctx, unit, opts, args...)
 }
 
 // Stop (deactivate) a given unit
-func Stop(ctx context.Context, unit string, opts Options) error {
-	args := []string{"stop", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
+//
+// Any additional arguments are passed directly to the systemctl command.
+func Stop(ctx context.Context, unit string, opts Options, args ...string) error {
+	return stop(ctx, unit, opts, args...)
 }
 
 // Unmask one or more unit files, as specified on the command line.
@@ -236,11 +144,8 @@ func Stop(ctx context.Context, unit string, opts Options) error {
 // doesn't exist, but only if it's not already masked.
 // If the unit doesn't exist but it's masked anyway, no error will be
 // returned. Gross, I know. Take it up with Poettering.
-func Unmask(ctx context.Context, unit string, opts Options) error {
-	args := []string{"unmask", "--system", unit}
-	if opts.UserMode {
-		args[1] = "--user"
-	}
-	_, _, _, err := execute(ctx, args)
-	return err
+//
+// Any additional arguments are passed directly to the systemctl command.
+func Unmask(ctx context.Context, unit string, opts Options, args ...string) error {
+	return unmask(ctx, unit, opts, args...)
 }

systemctl_darwin.go

@@ -0,0 +1,65 @@
+//go:build !linux
+
+package systemctl
+
+import (
+	"context"
+
+	"github.com/taigrr/systemctl/properties"
+)
+
+func daemonReload(_ context.Context, _ Options, _ ...string) error {
+	return nil
+}
+
+func reenable(_ context.Context, _ string, _ Options, _ ...string) error {
+	return nil
+}
+
+func disable(_ context.Context, _ string, _ Options, _ ...string) error {
+	return nil
+}
+
+func enable(_ context.Context, _ string, _ Options, _ ...string) error {
+	return nil
+}
+
+func isActive(_ context.Context, _ string, _ Options, _ ...string) (bool, error) {
+	return false, nil
+}
+
+func isEnabled(_ context.Context, _ string, _ Options, _ ...string) (bool, error) {
+	return false, nil
+}
+
+func isFailed(_ context.Context, _ string, _ Options, _ ...string) (bool, error) {
+	return false, nil
+}
+
+func mask(_ context.Context, _ string, _ Options, _ ...string) error {
+	return nil
+}
+
+func restart(_ context.Context, _ string, _ Options, _ ...string) error {
+	return nil
+}
+
+func show(_ context.Context, _ string, _ properties.Property, _ Options, _ ...string) (string, error) {
+	return "", nil
+}
+
+func start(_ context.Context, _ string, _ Options, _ ...string) error {
+	return nil
+}
+
+func status(_ context.Context, _ string, _ Options, _ ...string) (string, error) {
+	return "", nil
+}
+
+func stop(_ context.Context, _ string, _ Options, _ ...string) error {
+	return nil
+}
+
+func unmask(_ context.Context, _ string, _ Options, _ ...string) error {
+	return nil
+}

systemctl_linux.go

@@ -0,0 +1,149 @@
+//go:build linux
+
+package systemctl
+
+import (
+	"context"
+	"strings"
+
+	"github.com/taigrr/systemctl/properties"
+)
+
+func daemonReload(ctx context.Context, opts Options, args ...string) error {
+	a := prepareArgs("daemon-reload", opts, args...)
+	_, _, _, err := execute(ctx, a)
+	return err
+}
+
+func reenable(ctx context.Context, unit string, opts Options, args ...string) error {
+	a := prepareArgs("reenable", opts, append([]string{unit}, args...)...)
+	_, _, _, err := execute(ctx, a)
+	return err
+}
+
+func disable(ctx context.Context, unit string, opts Options, args ...string) error {
+	a := prepareArgs("disable", opts, append([]string{unit}, args...)...)
+	_, _, _, err := execute(ctx, a)
+	return err
+}
+
+func enable(ctx context.Context, unit string, opts Options, args ...string) error {
+	a := prepareArgs("enable", opts, append([]string{unit}, args...)...)
+	_, _, _, err := execute(ctx, a)
+	return err
+}
+
+func isActive(ctx context.Context, unit string, opts Options, args ...string) (bool, error) {
+	a := prepareArgs("is-active", opts, append([]string{unit}, args...)...)
+	stdout, _, _, err := execute(ctx, a)
+	stdout = strings.TrimSuffix(stdout, "\n")
+	switch stdout {
+	case "inactive":
+		return false, nil
+	case "active":
+		return true, nil
+	case "failed":
+		return false, nil
+	case "activating":
+		return false, nil
+	default:
+		return false, err
+	}
+}
+
+func isEnabled(ctx context.Context, unit string, opts Options, args ...string) (bool, error) {
+	a := prepareArgs("is-enabled", opts, append([]string{unit}, args...)...)
+	stdout, _, _, err := execute(ctx, a)
+	stdout = strings.TrimSuffix(stdout, "\n")
+	switch stdout {
+	case "enabled":
+		return true, nil
+	case "enabled-runtime":
+		return true, nil
+	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, ErrUnspecified
+}
+
+func isFailed(ctx context.Context, unit string, opts Options, args ...string) (bool, error) {
+	a := prepareArgs("is-failed", opts, append([]string{unit}, args...)...)
+	stdout, _, _, err := execute(ctx, a)
+	stdout = strings.TrimSuffix(stdout, "\n")
+	switch stdout {
+	case "inactive":
+		return false, nil
+	case "active":
+		return false, nil
+	case "failed":
+		return true, nil
+	default:
+		return false, err
+	}
+}
+
+func mask(ctx context.Context, unit string, opts Options, args ...string) error {
+	a := prepareArgs("mask", opts, append([]string{unit}, args...)...)
+	_, _, _, err := execute(ctx, a)
+	return err
+}
+
+func restart(ctx context.Context, unit string, opts Options, args ...string) error {
+	a := prepareArgs("restart", opts, append([]string{unit}, args...)...)
+	_, _, _, err := execute(ctx, a)
+	return err
+}
+
+func show(ctx context.Context, unit string, property properties.Property, opts Options, args ...string) (string, error) {
+	extra := append([]string{unit, "--property", string(property)}, args...)
+	a := prepareArgs("show", opts, extra...)
+	stdout, _, _, err := execute(ctx, a)
+	stdout = strings.TrimPrefix(stdout, string(property)+"=")
+	stdout = strings.TrimSuffix(stdout, "\n")
+	return stdout, err
+}
+
+func start(ctx context.Context, unit string, opts Options, args ...string) error {
+	a := prepareArgs("start", opts, append([]string{unit}, args...)...)
+	_, _, _, err := execute(ctx, a)
+	return err
+}
+
+func status(ctx context.Context, unit string, opts Options, args ...string) (string, error) {
+	a := prepareArgs("status", opts, append([]string{unit}, args...)...)
+	stdout, _, _, err := execute(ctx, a)
+	return stdout, err
+}
+
+func stop(ctx context.Context, unit string, opts Options, args ...string) error {
+	a := prepareArgs("stop", opts, append([]string{unit}, args...)...)
+	_, _, _, err := execute(ctx, a)
+	return err
+}
+
+func unmask(ctx context.Context, unit string, opts Options, args ...string) error {
+	a := prepareArgs("unmask", opts, append([]string{unit}, args...)...)
+	_, _, _, err := execute(ctx, a)
+	return err
+}

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 {
-	case ErrMasked:
+	switch {
+	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
-		if userString != "root" && userString != "system" {
-			userMode = true
-		}
+		userMode := userString != "root" && userString != "system"
+
 		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)
-		if err != nil {
-			t.Errorf("error asserting %s is up: %v", unit, err)
+		running, errIsActive := IsActive(ctx, unit, opts)
+		if errIsActive != nil {
+			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
-		if userString != "root" && userString != "system" {
-			userMode = true
-		}
+		userMode := userString != "root" && userString != "system"
+
 		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

@@ -3,23 +3,19 @@ package systemctl
 import (
 	"bytes"
 	"context"
+	"errors"
 	"fmt"
-	"log"
 	"os/exec"
-	"regexp"
+	"strings"
 )
 
 var systemctl string
 
+// killed is the exit code returned when a process is terminated by SIGINT.
 const killed = 130
 
 func init() {
-	path, err := exec.LookPath("systemctl")
-	if err != nil {
-		log.Printf("%v", ErrNotInstalled)
-		systemctl = ""
-		return
-	}
+	path, _ := exec.LookPath("systemctl")
 	systemctl = path
 }
 
@@ -34,7 +30,7 @@ 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
@@ -44,6 +40,10 @@ func execute(ctx context.Context, args []string) (string, string, int, error) {
 	warnings = stderr.String()
 	code = cmd.ProcessState.ExitCode()
 
+	if code == killed {
+		return output, warnings, code, ErrExecTimeout
+	}
+
 	customErr := filterErr(warnings)
 	if customErr != nil {
 		err = customErr
@@ -55,33 +55,41 @@ func execute(ctx context.Context, args []string) (string, string, int, error) {
 	return output, warnings, code, err
 }
 
-func filterErr(stderr string) error {
-	if matched, _ := regexp.MatchString(`does not exist`, stderr); matched {
-		return ErrDoesNotExist
+// prepareArgs builds the systemctl command arguments from a base command,
+// options, and any additional arguments the caller wants to pass through.
+func prepareArgs(base string, opts Options, extra ...string) []string {
+	args := make([]string, 0, 2+len(extra))
+	args = append(args, base)
+	if opts.UserMode {
+		args = append(args, "--user")
+	} else {
+		args = append(args, "--system")
+	}
+	args = append(args, extra...)
+	return args
+}
+
+func filterErr(stderr string) error {
+	switch {
+	case strings.Contains(stderr, `does not exist`):
+		return errors.Join(ErrDoesNotExist, fmt.Errorf("stderr: %s", stderr))
+	case strings.Contains(stderr, `not found.`):
+		return errors.Join(ErrDoesNotExist, fmt.Errorf("stderr: %s", stderr))
+	case strings.Contains(stderr, `not loaded.`):
+		return errors.Join(ErrUnitNotLoaded, fmt.Errorf("stderr: %s", stderr))
+	case strings.Contains(stderr, `No such file or directory`):
+		return errors.Join(ErrDoesNotExist, fmt.Errorf("stderr: %s", stderr))
+	case strings.Contains(stderr, `Interactive authentication required`):
+		return errors.Join(ErrInsufficientPermissions, fmt.Errorf("stderr: %s", stderr))
+	case strings.Contains(stderr, `Access denied`):
+		return errors.Join(ErrInsufficientPermissions, fmt.Errorf("stderr: %s", stderr))
+	case strings.Contains(stderr, `DBUS_SESSION_BUS_ADDRESS`):
+		return errors.Join(ErrBusFailure, fmt.Errorf("stderr: %s", stderr))
+	case strings.Contains(stderr, `is masked`):
+		return errors.Join(ErrMasked, fmt.Errorf("stderr: %s", stderr))
+	case strings.Contains(stderr, `Failed`):
+		return errors.Join(ErrUnspecified, fmt.Errorf("stderr: %s", stderr))
+	default:
+		return nil
 	}
-	if matched, _ := regexp.MatchString(`not found.`, stderr); matched {
-		return ErrDoesNotExist
-	}
-	if matched, _ := regexp.MatchString(`not loaded.`, stderr); matched {
-		return ErrUnitNotLoaded
-	}
-	if matched, _ := regexp.MatchString(`No such file or directory`, stderr); matched {
-		return ErrDoesNotExist
-	}
-	if matched, _ := regexp.MatchString(`Interactive authentication required`, stderr); matched {
-		return ErrInsufficientPermissions
-	}
-	if matched, _ := regexp.MatchString(`Access denied`, stderr); matched {
-		return ErrInsufficientPermissions
-	}
-	if matched, _ := regexp.MatchString(`DBUS_SESSION_BUS_ADDRESS`, stderr); matched {
-		return ErrBusFailure
-	}
-	if matched, _ := regexp.MatchString(`is masked`, stderr); matched {
-		return ErrMasked
-	}
-	if matched, _ := regexp.MatchString(`Failed`, stderr); matched {
-		return ErrUnspecified
-	}
-	return nil
 }

util_test.go

@@ -0,0 +1,62 @@
+package systemctl
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestPrepareArgs(t *testing.T) {
+	tests := []struct {
+		name     string
+		base     string
+		opts     Options
+		extra    []string
+		expected []string
+	}{
+		{
+			name:     "system mode no extra",
+			base:     "start",
+			opts:     Options{},
+			extra:    nil,
+			expected: []string{"start", "--system"},
+		},
+		{
+			name:     "user mode no extra",
+			base:     "start",
+			opts:     Options{UserMode: true},
+			extra:    nil,
+			expected: []string{"start", "--user"},
+		},
+		{
+			name:     "system mode with unit",
+			base:     "start",
+			opts:     Options{},
+			extra:    []string{"nginx.service"},
+			expected: []string{"start", "--system", "nginx.service"},
+		},
+		{
+			name:     "user mode with unit and extra args",
+			base:     "restart",
+			opts:     Options{UserMode: true},
+			extra:    []string{"foo.service", "--no-block"},
+			expected: []string{"restart", "--user", "foo.service", "--no-block"},
+		},
+		{
+			name:     "daemon-reload no extra",
+			base:     "daemon-reload",
+			opts:     Options{},
+			extra:    nil,
+			expected: []string{"daemon-reload", "--system"},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := prepareArgs(tt.base, tt.opts, tt.extra...)
+			if !reflect.DeepEqual(got, tt.expected) {
+				t.Errorf("prepareArgs(%q, %+v, %v) = %v, want %v",
+					tt.base, tt.opts, tt.extra, got, tt.expected)
+			}
+		})
+	}
+}