core: migrate to dankgo shared go modules, embed quickshell in DMS

binary to mount at runtime, -c or DMS_SHELL_DIR overrides required to
explicitly override embedded configuration

core/cmd/dms/shell.go

@@ -4,591 +4,20 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"io"
 	"os"
 	"os/exec"
-	"os/signal"
 	"path/filepath"
 	"slices"
 	"strconv"
 	"strings"
 	"sync"
-	"syscall"
 	"time"
 
 	"github.com/AvengeMedia/DankMaterialShell/core/internal/log"
-	"github.com/AvengeMedia/DankMaterialShell/core/internal/server"
 )
 
 type ipcTargets map[string]map[string][]string
 
-// getProcessExitCode returns the exit code from a ProcessState.
-// For normal exits, returns the exit code directly.
-// For signal termination, returns 128 + signal number (Unix convention).
-func getProcessExitCode(state *os.ProcessState) int {
-	if state == nil {
-		return 1
-	}
-	if code := state.ExitCode(); code != -1 {
-		return code
-	}
-	// Process was killed by signal - extract signal number
-	if status, ok := state.Sys().(syscall.WaitStatus); ok {
-		if status.Signaled() {
-			return 128 + int(status.Signal())
-		}
-	}
-	return 1
-}
-
-var isSessionManaged bool
-
-func execDetachedRestart(targetPID int) {
-	selfPath, err := os.Executable()
-	if err != nil {
-		return
-	}
-
-	cmd := exec.Command(selfPath, "restart-detached", strconv.Itoa(targetPID))
-	cmd.SysProcAttr = &syscall.SysProcAttr{
-		Setsid: true,
-	}
-	cmd.Start()
-}
-
-func runDetachedRestart(targetPIDStr string) {
-	targetPID, err := strconv.Atoi(targetPIDStr)
-	if err != nil {
-		return
-	}
-
-	time.Sleep(200 * time.Millisecond)
-
-	proc, err := os.FindProcess(targetPID)
-	if err == nil {
-		proc.Signal(syscall.SIGTERM)
-	}
-
-	time.Sleep(500 * time.Millisecond)
-
-	killShell()
-	runShellDaemon(false)
-}
-
-func getRuntimeDir() string {
-	if runtime := os.Getenv("XDG_RUNTIME_DIR"); runtime != "" {
-		return runtime
-	}
-	return os.TempDir()
-}
-
-func appendLogEnv(env []string) []string {
-	if v := os.Getenv("DMS_LOG_LEVEL"); v != "" {
-		env = append(env, "DMS_LOG_LEVEL="+v)
-	}
-	if v := os.Getenv("DMS_LOG_FILE"); v != "" {
-		env = append(env, "DMS_LOG_FILE="+v)
-	}
-	return env
-}
-
-func withDMSExecutable(env []string) []string {
-	selfPath, err := os.Executable()
-	if err != nil {
-		return env
-	}
-	return append(env, "DMS_EXECUTABLE="+selfPath)
-}
-
-func hasSystemdRun() bool {
-	_, err := exec.LookPath("systemd-run")
-	return err == nil
-}
-
-func getPIDFilePath() string {
-	return filepath.Join(getRuntimeDir(), fmt.Sprintf("danklinux-%d.pid", os.Getpid()))
-}
-
-func getSessionFilePath() string {
-	return filepath.Join(getRuntimeDir(), fmt.Sprintf("danklinux-%d.session", os.Getpid()))
-}
-
-func writePIDFile(childPID int) error {
-	pidFile := getPIDFilePath()
-	if display := os.Getenv("WAYLAND_DISPLAY"); display != "" {
-		if err := os.WriteFile(getSessionFilePath(), []byte(display), 0o644); err != nil {
-			log.Warnf("Failed to write session file: %v", err)
-		}
-	}
-	return os.WriteFile(pidFile, []byte(strconv.Itoa(childPID)), 0o644)
-}
-
-func removePIDFile() {
-	os.Remove(getPIDFilePath())
-	os.Remove(getSessionFilePath())
-}
-
-func getAllDMSPIDs() []int {
-	dir := getRuntimeDir()
-	entries, err := os.ReadDir(dir)
-	if err != nil {
-		return nil
-	}
-
-	var pids []int
-
-	for _, entry := range entries {
-		if !strings.HasPrefix(entry.Name(), "danklinux-") || !strings.HasSuffix(entry.Name(), ".pid") {
-			continue
-		}
-
-		pidFile := filepath.Join(dir, entry.Name())
-		data, err := os.ReadFile(pidFile)
-		if err != nil {
-			continue
-		}
-
-		childPID, err := strconv.Atoi(strings.TrimSpace(string(data)))
-		if err != nil {
-			os.Remove(pidFile)
-			continue
-		}
-
-		proc, err := os.FindProcess(childPID)
-		if err != nil {
-			os.Remove(pidFile)
-			continue
-		}
-
-		if err := proc.Signal(syscall.Signal(0)); err != nil {
-			os.Remove(pidFile)
-			continue
-		}
-
-		pids = append(pids, childPID)
-
-		parentPIDStr := strings.TrimPrefix(entry.Name(), "danklinux-")
-		parentPIDStr = strings.TrimSuffix(parentPIDStr, ".pid")
-		if parentPID, err := strconv.Atoi(parentPIDStr); err == nil {
-			if parentProc, err := os.FindProcess(parentPID); err == nil {
-				if err := parentProc.Signal(syscall.Signal(0)); err == nil {
-					pids = append(pids, parentPID)
-				}
-			}
-		}
-	}
-
-	return pids
-}
-
-func runShellInteractive(session bool) {
-	isSessionManaged = session
-	go printASCII()
-	fmt.Fprintf(os.Stderr, "dms %s\n", Version)
-
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-
-	socketPath := server.GetSocketPath()
-
-	configStateFile := filepath.Join(getRuntimeDir(), "danklinux.path")
-	if err := os.WriteFile(configStateFile, []byte(configPath), 0o644); err != nil {
-		log.Warnf("Failed to write config state file: %v", err)
-	}
-	defer os.Remove(configStateFile)
-
-	errChan := make(chan error, 2)
-
-	go func() {
-		defer func() {
-			if r := recover(); r != nil {
-				errChan <- fmt.Errorf("server panic: %v", r)
-			}
-		}()
-		server.CLIVersion = Version
-		if err := server.Start(false); err != nil {
-			errChan <- fmt.Errorf("server error: %w", err)
-		}
-	}()
-
-	ensureFontCache()
-	log.Infof("Spawning quickshell with -p %s", configPath)
-
-	cmd := exec.CommandContext(ctx, "qs", "-p", configPath)
-	cmd.Env = withDMSExecutable(append(os.Environ(), "DMS_SOCKET="+socketPath))
-	if os.Getenv("QT_LOGGING_RULES") == "" {
-		if qtRules := log.GetQtLoggingRules(); qtRules != "" {
-			cmd.Env = append(cmd.Env, "QT_LOGGING_RULES="+qtRules)
-		}
-	}
-
-	if isSessionManaged && hasSystemdRun() {
-		cmd.Env = append(cmd.Env, "DMS_DEFAULT_LAUNCH_PREFIX=systemd-run --user --scope")
-	}
-
-	homeDir, err := os.UserHomeDir()
-	if err == nil && os.Getenv("DMS_DISABLE_HOT_RELOAD") == "" {
-		if !strings.HasPrefix(configPath, homeDir) {
-			cmd.Env = append(cmd.Env, "DMS_DISABLE_HOT_RELOAD=1")
-		}
-	}
-
-	if os.Getenv("QT_QPA_PLATFORMTHEME") == "" {
-		cmd.Env = append(cmd.Env, "QT_QPA_PLATFORMTHEME=gtk3")
-	}
-	if os.Getenv("QT_QPA_PLATFORMTHEME_QT6") == "" {
-		cmd.Env = append(cmd.Env, "QT_QPA_PLATFORMTHEME_QT6=gtk3")
-	}
-	if os.Getenv("QT_QPA_PLATFORM") == "" {
-		cmd.Env = append(cmd.Env, "QT_QPA_PLATFORM=wayland;xcb")
-	}
-	if os.Getenv("QSG_USE_SIMPLE_ANIMATION_DRIVER") == "" {
-		cmd.Env = append(cmd.Env, "QSG_USE_SIMPLE_ANIMATION_DRIVER=1")
-	}
-
-	cmd.Env = appendLogEnv(cmd.Env)
-
-	cmd.Stdin = os.Stdin
-	cmd.Stdout = os.Stdout
-	tracker := &stderrTracker{parent: os.Stderr}
-	cmd.Stderr = tracker
-
-	startTime := time.Now()
-	if err := cmd.Start(); err != nil {
-		log.Fatalf("Error starting quickshell: %v", err)
-	}
-
-	// Write PID file for the quickshell child process
-	if err := writePIDFile(cmd.Process.Pid); err != nil {
-		log.Warnf("Failed to write PID file: %v", err)
-	}
-	defer removePIDFile()
-
-	defer func() {
-		if cmd.Process != nil {
-			cmd.Process.Signal(syscall.SIGTERM)
-		}
-	}()
-
-	sigChan := make(chan os.Signal, 1)
-	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM, syscall.SIGUSR1)
-
-	go func() {
-		if err := cmd.Wait(); err != nil {
-			errChan <- fmt.Errorf("quickshell exited: %w", err)
-		} else {
-			errChan <- fmt.Errorf("quickshell exited")
-		}
-	}()
-
-	for {
-		select {
-		case sig := <-sigChan:
-			if sig == syscall.SIGUSR1 {
-				if isSessionManaged {
-					log.Infof("Received SIGUSR1, exiting for systemd restart...")
-					cancel()
-					cmd.Process.Signal(syscall.SIGTERM)
-					os.Remove(socketPath)
-					os.Exit(1)
-				}
-				log.Infof("Received SIGUSR1, spawning detached restart process...")
-				execDetachedRestart(os.Getpid())
-				return
-			}
-
-			// Check if qs already crashed before we got SIGTERM (systemd sends SIGTERM when D-Bus name is released)
-			select {
-			case <-errChan:
-				cancel()
-				os.Remove(socketPath)
-				exitCode := getProcessExitCode(cmd.ProcessState)
-				logStartupFailure(startTime, exitCode, tracker)
-				os.Exit(exitCode)
-			case <-time.After(500 * time.Millisecond):
-			}
-
-			log.Infof("\nReceived signal %v, shutting down...", sig)
-			cancel()
-			cmd.Process.Signal(syscall.SIGTERM)
-			os.Remove(socketPath)
-			return
-
-		case err := <-errChan:
-			log.Error(err)
-			cancel()
-			if cmd.Process != nil {
-				cmd.Process.Signal(syscall.SIGTERM)
-			}
-			os.Remove(socketPath)
-			exitCode := getProcessExitCode(cmd.ProcessState)
-			logStartupFailure(startTime, exitCode, tracker)
-			os.Exit(exitCode)
-		}
-	}
-}
-
-func restartShell() {
-	pids := getAllDMSPIDs()
-
-	if len(pids) == 0 {
-		log.Info("No running DMS shell instances found. Starting daemon...")
-		runShellDaemon(false)
-		return
-	}
-
-	currentPid := os.Getpid()
-	uniquePids := make(map[int]bool)
-
-	for _, pid := range pids {
-		if pid != currentPid {
-			uniquePids[pid] = true
-		}
-	}
-
-	for pid := range uniquePids {
-		proc, err := os.FindProcess(pid)
-		if err != nil {
-			log.Errorf("Error finding process %d: %v", pid, err)
-			continue
-		}
-
-		if err := proc.Signal(syscall.Signal(0)); err != nil {
-			continue
-		}
-
-		if err := proc.Signal(syscall.SIGUSR1); err != nil {
-			log.Errorf("Error sending SIGUSR1 to process %d: %v", pid, err)
-		} else {
-			log.Infof("Sent SIGUSR1 to DMS process with PID %d", pid)
-		}
-	}
-}
-
-func killShell() {
-	pids := getAllDMSPIDs()
-
-	if len(pids) == 0 {
-		log.Info("No running DMS shell instances found.")
-		return
-	}
-
-	currentPid := os.Getpid()
-	uniquePids := make(map[int]bool)
-
-	for _, pid := range pids {
-		if pid != currentPid {
-			uniquePids[pid] = true
-		}
-	}
-
-	for pid := range uniquePids {
-		proc, err := os.FindProcess(pid)
-		if err != nil {
-			log.Errorf("Error finding process %d: %v", pid, err)
-			continue
-		}
-
-		if err := proc.Signal(syscall.Signal(0)); err != nil {
-			continue
-		}
-
-		if err := proc.Kill(); err != nil {
-			log.Errorf("Error killing process %d: %v", pid, err)
-		} else {
-			log.Infof("Killed DMS process with PID %d", pid)
-		}
-	}
-
-	dir := getRuntimeDir()
-	entries, err := os.ReadDir(dir)
-	if err != nil {
-		return
-	}
-
-	for _, entry := range entries {
-		if !strings.HasPrefix(entry.Name(), "danklinux-") {
-			continue
-		}
-		if strings.HasSuffix(entry.Name(), ".pid") || strings.HasSuffix(entry.Name(), ".session") {
-			os.Remove(filepath.Join(dir, entry.Name()))
-		}
-	}
-}
-
-func runShellDaemon(session bool) {
-	isSessionManaged = session
-	isDaemonChild := slices.Contains(os.Args, "--daemon-child")
-
-	if !isDaemonChild {
-		fmt.Fprintf(os.Stderr, "dms %s\n", Version)
-
-		cmd := exec.Command(os.Args[0], "run", "-d", "--daemon-child")
-		cmd.Env = os.Environ()
-
-		cmd.SysProcAttr = &syscall.SysProcAttr{
-			Setsid: true,
-		}
-
-		if err := cmd.Start(); err != nil {
-			log.Fatalf("Error starting daemon: %v", err)
-		}
-
-		log.Infof("DMS shell daemon started (PID: %d)", cmd.Process.Pid)
-		return
-	}
-
-	fmt.Fprintf(os.Stderr, "dms %s\n", Version)
-
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-
-	socketPath := server.GetSocketPath()
-
-	configStateFile := filepath.Join(getRuntimeDir(), "danklinux.path")
-	if err := os.WriteFile(configStateFile, []byte(configPath), 0o644); err != nil {
-		log.Warnf("Failed to write config state file: %v", err)
-	}
-	defer os.Remove(configStateFile)
-
-	errChan := make(chan error, 2)
-
-	go func() {
-		defer func() {
-			if r := recover(); r != nil {
-				errChan <- fmt.Errorf("server panic: %v", r)
-			}
-		}()
-		server.CLIVersion = Version
-		if err := server.Start(false); err != nil {
-			errChan <- fmt.Errorf("server error: %w", err)
-		}
-	}()
-
-	ensureFontCache()
-	log.Infof("Spawning quickshell with -p %s", configPath)
-
-	cmd := exec.CommandContext(ctx, "qs", "-p", configPath)
-	cmd.Env = withDMSExecutable(append(os.Environ(), "DMS_SOCKET="+socketPath))
-	if os.Getenv("QT_LOGGING_RULES") == "" {
-		if qtRules := log.GetQtLoggingRules(); qtRules != "" {
-			cmd.Env = append(cmd.Env, "QT_LOGGING_RULES="+qtRules)
-		}
-	}
-
-	// ! TODO - remove when QS 0.3 is up and we can use the pragma
-	cmd.Env = append(cmd.Env, "QS_APP_ID=com.danklinux.dms")
-
-	if isSessionManaged && hasSystemdRun() {
-		cmd.Env = append(cmd.Env, "DMS_DEFAULT_LAUNCH_PREFIX=systemd-run --user --scope")
-	}
-
-	homeDir, err := os.UserHomeDir()
-	if err == nil && os.Getenv("DMS_DISABLE_HOT_RELOAD") == "" {
-		if !strings.HasPrefix(configPath, homeDir) {
-			cmd.Env = append(cmd.Env, "DMS_DISABLE_HOT_RELOAD=1")
-		}
-	}
-
-	if os.Getenv("QT_QPA_PLATFORMTHEME") == "" {
-		cmd.Env = append(cmd.Env, "QT_QPA_PLATFORMTHEME=gtk3")
-	}
-	if os.Getenv("QT_QPA_PLATFORMTHEME_QT6") == "" {
-		cmd.Env = append(cmd.Env, "QT_QPA_PLATFORMTHEME_QT6=gtk3")
-	}
-	if os.Getenv("QT_QPA_PLATFORM") == "" {
-		cmd.Env = append(cmd.Env, "QT_QPA_PLATFORM=wayland;xcb")
-	}
-	if os.Getenv("QSG_USE_SIMPLE_ANIMATION_DRIVER") == "" {
-		cmd.Env = append(cmd.Env, "QSG_USE_SIMPLE_ANIMATION_DRIVER=1")
-	}
-
-	cmd.Env = appendLogEnv(cmd.Env)
-
-	devNull, err := os.OpenFile("/dev/null", os.O_RDWR, 0)
-	if err != nil {
-		log.Fatalf("Error opening /dev/null: %v", err)
-	}
-	defer devNull.Close()
-
-	cmd.Stdin = devNull
-	cmd.Stdout = devNull
-	tracker := &stderrTracker{parent: devNull}
-	cmd.Stderr = tracker
-
-	startTime := time.Now()
-	if err := cmd.Start(); err != nil {
-		log.Fatalf("Error starting daemon: %v", err)
-	}
-
-	// Write PID file for the quickshell child process
-	if err := writePIDFile(cmd.Process.Pid); err != nil {
-		log.Warnf("Failed to write PID file: %v", err)
-	}
-	defer removePIDFile()
-
-	defer func() {
-		if cmd.Process != nil {
-			cmd.Process.Signal(syscall.SIGTERM)
-		}
-	}()
-
-	sigChan := make(chan os.Signal, 1)
-	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM, syscall.SIGUSR1)
-
-	go func() {
-		if err := cmd.Wait(); err != nil {
-			errChan <- fmt.Errorf("quickshell exited: %w", err)
-		} else {
-			errChan <- fmt.Errorf("quickshell exited")
-		}
-	}()
-
-	for {
-		select {
-		case sig := <-sigChan:
-			if sig == syscall.SIGUSR1 {
-				if isSessionManaged {
-					log.Infof("Received SIGUSR1, exiting for systemd restart...")
-					cancel()
-					cmd.Process.Signal(syscall.SIGTERM)
-					os.Remove(socketPath)
-					os.Exit(1)
-				}
-				log.Infof("Received SIGUSR1, spawning detached restart process...")
-				execDetachedRestart(os.Getpid())
-				return
-			}
-
-			// Check if qs already crashed before we got SIGTERM (systemd sends SIGTERM when D-Bus name is released)
-			select {
-			case <-errChan:
-				cancel()
-				os.Remove(socketPath)
-				exitCode := getProcessExitCode(cmd.ProcessState)
-				logStartupFailure(startTime, exitCode, tracker)
-				os.Exit(exitCode)
-			case <-time.After(500 * time.Millisecond):
-			}
-
-			cancel()
-			cmd.Process.Signal(syscall.SIGTERM)
-			os.Remove(socketPath)
-			return
-
-		case <-errChan:
-			cancel()
-			if cmd.Process != nil {
-				cmd.Process.Signal(syscall.SIGTERM)
-			}
-			os.Remove(socketPath)
-			exitCode := getProcessExitCode(cmd.ProcessState)
-			logStartupFailure(startTime, exitCode, tracker)
-			os.Exit(exitCode)
-		}
-	}
-}
-
 var qsHasAnyDisplay = sync.OnceValue(func() bool {
 	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
 	defer cancel()
@@ -632,17 +61,17 @@ func parseTargetsFromIPCShowOutput(output string) ipcTargets {
 
 func buildQsIPCBaseArgs() ([]string, error) {
 	cmdArgs := []string{"ipc"}
-	switch pid, ok := getSessionDMSPID(); {
+	switch pid, ok := shellApp.SessionPID(); {
 	case ok:
 		cmdArgs = append(cmdArgs, "--pid", strconv.Itoa(pid))
 	default:
-		if err := findConfig(nil, nil); err != nil {
+		if err := shellApp.ResolveConfig(nil, nil); err != nil {
 			return nil, err
 		}
 		if qsHasAnyDisplay() {
 			cmdArgs = append(cmdArgs, "--any-display")
 		}
-		cmdArgs = append(cmdArgs, "-p", configPath)
+		cmdArgs = append(cmdArgs, "-p", shellApp.ConfigPath())
 	}
 	return cmdArgs, nil
 }
@@ -699,101 +128,6 @@ func getShellIPCCompletions(args []string, _ string) []string {
 	return nil
 }
 
-func getFirstDMSPID() (int, bool) {
-	dir := getRuntimeDir()
-	entries, err := os.ReadDir(dir)
-	if err != nil {
-		return 0, false
-	}
-
-	for _, entry := range entries {
-		if !strings.HasPrefix(entry.Name(), "danklinux-") || !strings.HasSuffix(entry.Name(), ".pid") {
-			continue
-		}
-
-		data, err := os.ReadFile(filepath.Join(dir, entry.Name()))
-		if err != nil {
-			continue
-		}
-
-		pid, err := strconv.Atoi(strings.TrimSpace(string(data)))
-		if err != nil {
-			continue
-		}
-
-		proc, err := os.FindProcess(pid)
-		if err != nil {
-			continue
-		}
-
-		if proc.Signal(syscall.Signal(0)) != nil {
-			continue
-		}
-
-		return pid, true
-	}
-
-	return 0, false
-}
-
-func sessionParentPID(display string) (int, bool) {
-	if display == "" {
-		return 0, false
-	}
-
-	dir := getRuntimeDir()
-	entries, err := os.ReadDir(dir)
-	if err != nil {
-		return 0, false
-	}
-
-	for _, entry := range entries {
-		name := entry.Name()
-		if !strings.HasPrefix(name, "danklinux-") || !strings.HasSuffix(name, ".session") {
-			continue
-		}
-
-		data, err := os.ReadFile(filepath.Join(dir, name))
-		if err != nil || strings.TrimSpace(string(data)) != display {
-			continue
-		}
-
-		parentStr := strings.TrimSuffix(strings.TrimPrefix(name, "danklinux-"), ".session")
-		parentPID, err := strconv.Atoi(parentStr)
-		if err != nil {
-			continue
-		}
-
-		return parentPID, true
-	}
-
-	return 0, false
-}
-
-func getSessionDMSPID() (int, bool) {
-	parentPID, ok := sessionParentPID(os.Getenv("WAYLAND_DISPLAY"))
-	if !ok {
-		return getFirstDMSPID()
-	}
-
-	data, err := os.ReadFile(filepath.Join(getRuntimeDir(), fmt.Sprintf("danklinux-%d.pid", parentPID)))
-	if err != nil {
-		return getFirstDMSPID()
-	}
-
-	pid, err := strconv.Atoi(strings.TrimSpace(string(data)))
-	if err != nil {
-		return getFirstDMSPID()
-	}
-
-	proc, err := os.FindProcess(pid)
-	if err != nil || proc.Signal(syscall.Signal(0)) != nil {
-		return getFirstDMSPID()
-	}
-
-	return pid, true
-}
-
 func runShellIPCCommand(args []string) {
 	if len(args) == 0 {
 		printIPCHelp()
@@ -946,36 +280,12 @@ func rebuildFontCache() {
 	}
 }
 
-type stderrTracker struct {
-	mu     sync.Mutex
-	buf    strings.Builder
-	parent io.Writer
-}
-
-func (s *stderrTracker) Write(p []byte) (n int, err error) {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	if s.buf.Len() < 8192 {
-		s.buf.Write(p)
-	}
-	if s.parent != nil {
-		return s.parent.Write(p)
-	}
-	return len(p), nil
-}
-
-func (s *stderrTracker) String() string {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	return s.buf.String()
-}
-
 // logStartupFailure logs diagnostic advice if qs crashes within 5s of launch.
-func logStartupFailure(startTime time.Time, exitCode int, tracker *stderrTracker) {
-	if time.Since(startTime) >= 5*time.Second || exitCode == 0 || exitCode > 128 {
+func logStartupFailure(exitCode int, uptime time.Duration, stderrTail string) {
+	if uptime >= 5*time.Second || exitCode == 0 || exitCode > 128 {
 		return
 	}
-	if containsFontCrashSignature(tracker.String()) {
+	if containsFontCrashSignature(stderrTail) {
 		log.Errorf("DMS startup failed due to a potential font/rendering crash. Try running 'fc-cache -fv' and restarting DMS.")
 	} else {
 		log.Errorf("DMS startup failed (exit code %d). Run 'dms doctor' for more diagnostics.", exitCode)