[feat] add lock screen on disconnect option, refs #125

apps/desktop/src/platform/linux/headless/headless_settings.cpp

@@ -40,6 +40,7 @@ std::vector<ConsoleSetting> GetConsoleSettings(const ConfigCenter& config) {
       {"server_host", "console_setting_host", config.GetSignalServerHost(), "example.com"},
       {"server_port", "console_setting_port", std::to_string(config.GetSignalServerPort()), "1..65535"},
       {"privacy", "console_setting_privacy", OnOff(config.IsEnablePrivacyScreen()), "on / off"},
+      {"lock_on_disconnect", "lock_on_disconnect", OnOff(config.IsLockOnDisconnect()), "on / off"},
       {"file_path", "console_setting_files", config.GetFileTransferSavePath().empty() ? "default" : config.GetFileTransferSavePath(), "/path/to/directory / default"},
       {"autostart", "console_setting_autostart", OnOff(config.IsEnableAutostart()), "on / off"},
       {"daemon", "console_setting_daemon", OnOff(config.IsEnableDaemon()), "on / off"},
@@ -120,6 +121,8 @@ SettingResult ApplyConsoleSetting(ConfigCenter& config, const std::string& key,
       save = [&config, enabled] { return config.SetPrivacyScreen(enabled); };
       effect = SettingEffect::next_connection;
       message = "console_settings_next_connection";
+    } else if (key == "lock_on_disconnect") {
+      save = [&config, enabled] { return config.SetLockOnDisconnect(enabled); };
     } else if (key == "autostart") {
       save = [&config, enabled] { return config.SetAutostart(enabled); };
       effect = SettingEffect::next_login;

apps/desktop/src/platform/linux/screen_lock.cpp

@@ -0,0 +1,60 @@
+/*
+ * @Author: DI JUNKUN
+ * @Date: 2026-10-25
+ * Copyright (c) 2026 by DI JUNKUN, All Rights Reserved.
+ */
+
+#include "screen_lock.h"
+
+#include <dbus/dbus.h>
+
+#include "rd_log.h"
+
+namespace crossdesk {
+
+bool LockScreen() {
+  dbus_threads_init_default();
+  DBusError error;
+  dbus_error_init(&error);
+  DBusConnection* connection = dbus_bus_get_private(DBUS_BUS_SESSION, &error);
+  if (!connection) {
+    LOG_WARN("Cannot connect to screen lock service: {}",
+             error.message ? error.message : "session bus unavailable");
+    dbus_error_free(&error);
+    return false;
+  }
+  dbus_connection_set_exit_on_disconnect(connection, false);
+
+  // Address the current desktop's session bus, including headless desktops;
+  // never lock every logged-in user or an unrelated system login session.
+  struct Service { const char* name; const char* path; };
+  constexpr Service services[] = {
+      {"org.freedesktop.ScreenSaver", "/ScreenSaver"},
+      {"org.gnome.ScreenSaver", "/org/gnome/ScreenSaver"},
+      {"org.cinnamon.ScreenSaver", "/org/cinnamon/ScreenSaver"},
+      {"org.mate.ScreenSaver", "/org/mate/ScreenSaver"},
+      {"org.xfce.ScreenSaver", "/org/xfce/ScreenSaver"},
+  };
+  bool accepted = false;
+  for (const auto& service : services) {
+    DBusMessage* message = dbus_message_new_method_call(
+        service.name, service.path, service.name, "Lock");
+    if (!message) break;
+    dbus_message_set_auto_start(message, false);
+    DBusMessage* reply = dbus_connection_send_with_reply_and_block(
+        connection, message, 1000, &error);
+    dbus_message_unref(message);
+    if (reply) {
+      accepted = dbus_message_get_type(reply) == DBUS_MESSAGE_TYPE_METHOD_RETURN;
+      dbus_message_unref(reply);
+    }
+    dbus_error_free(&error);
+    if (accepted) break;
+  }
+  dbus_connection_close(connection);
+  dbus_connection_unref(connection);
+  if (!accepted) LOG_WARN("No desktop screen lock service accepted the request");
+  return accepted;
+}
+
+}  // namespace crossdesk

apps/desktop/src/platform/macos/screen_lock.cpp

@@ -0,0 +1,35 @@
+/*
+ * @Author: DI JUNKUN
+ * @Date: 2026-10-25
+ * Copyright (c) 2026 by DI JUNKUN, All Rights Reserved.
+ */
+
+#include "screen_lock.h"
+
+#include <dlfcn.h>
+
+#include "rd_log.h"
+
+namespace crossdesk {
+
+bool LockScreen() {
+  // macOS has no public immediate-lock API. Resolve login.framework at
+  // runtime so an OS without this private entry point fails gracefully.
+  static void* framework = dlopen(
+      "/System/Library/PrivateFrameworks/login.framework/login",
+      RTLD_LAZY | RTLD_LOCAL);
+  using LockScreenFunction = int (*)();
+  static const auto lock = framework
+      ? reinterpret_cast<LockScreenFunction>(
+            dlsym(framework, "SACLockScreenImmediate"))
+      : nullptr;
+  if (!lock) {
+    LOG_WARN("macOS screen lock API is unavailable");
+    return false;
+  }
+  const int result = lock();
+  if (result != 0) LOG_WARN("macOS screen lock request failed: {}", result);
+  return result == 0;
+}
+
+}  // namespace crossdesk

apps/desktop/src/platform/windows/gui/application/unattended_application.cpp

@@ -45,6 +45,7 @@ int GuiApplication::RunUnattended(void* stop_event) {
       if (CreateConnectionPeer() != 0) CloseConnectionPeer();
     }
     HandleConnectionStatusChange();
+    HandleScreenLock();
     HandleWindowsServiceIntegration();
     devices_.UpdateInteractions();
     ShareLocalCursorState();
@@ -71,6 +72,7 @@ int GuiApplication::RunUnattended(void* stop_event) {
   devices_.DestroyDevices();
   devices_.DestroyFactories();
   privacy_.Shutdown();
+  HandleScreenLock();
   WriteUnattendedStatus(settings_.ActiveIdentity(), false, session);
   SDL_Quit();
   return 0;

apps/desktop/src/platform/windows/screen_lock.cpp

@@ -0,0 +1,21 @@
+/*
+ * @Author: DI JUNKUN
+ * @Date: 2026-10-25
+ * Copyright (c) 2026 by DI JUNKUN, All Rights Reserved.
+ */
+
+#include "screen_lock.h"
+
+#include <windows.h>
+
+#include "rd_log.h"
+
+namespace crossdesk {
+
+bool LockScreen() {
+  if (LockWorkStation()) return true;
+  LOG_WARN("LockWorkStation failed: {}", GetLastError());
+  return false;
+}
+
+}  // namespace crossdesk