Add hotplug detection of bluetooth controllers

include/modules/bluetooth.hpp

@@ -49,6 +49,9 @@ class Bluetooth : public ALabel {
   auto update() -> void override;
 
  private:
+  static auto onObjectAdded(GDBusObjectManager*, GDBusObject*, gpointer) -> void;
+  static auto onObjectRemoved(GDBusObjectManager*, GDBusObject*, gpointer) -> void;
+
   static auto onInterfaceAddedOrRemoved(GDBusObjectManager*, GDBusObject*, GDBusInterface*,
                                         gpointer) -> void;
   static auto onInterfaceProxyPropertiesChanged(GDBusObjectManagerClient*, GDBusObjectProxy*,

src/modules/bluetooth.cpp

@@ -98,19 +98,21 @@ waybar::modules::Bluetooth::Bluetooth(const std::string& id, const Json::Value&
                    std::back_inserter(device_preference_), [](auto x) { return x.asString(); });
   }
 
-  // NOTE: assumption made that the controller that is selected stays unchanged
-  // for duration of the module
   if (cur_controller_ = findCurController(); !cur_controller_) {
     if (config_["controller-alias"].isString()) {
-      spdlog::error("findCurController() failed: no bluetooth controller found with alias '{}'",
+      spdlog::warn("no bluetooth controller found with alias '{}'",
                     config_["controller-alias"].asString());
     } else {
-      spdlog::error("findCurController() failed: no bluetooth controller found");
+      spdlog::warn("no bluetooth controller found");
     }
     update();
   } else {
-    // These calls only make sense if a controller could be found
+    // This call only make sense if a controller could be found
     findConnectedDevices(cur_controller_->path, connected_devices_);
+  }
+
+  g_signal_connect(manager_.get(), "object-added", G_CALLBACK(onObjectAdded), this);
+  g_signal_connect(manager_.get(), "object-removed", G_CALLBACK(onObjectRemoved), this);
   g_signal_connect(manager_.get(), "interface-proxy-properties-changed",
                    G_CALLBACK(onInterfaceProxyPropertiesChanged), this);
   g_signal_connect(manager_.get(), "interface-added", G_CALLBACK(onInterfaceAddedOrRemoved),
@@ -121,7 +123,6 @@ waybar::modules::Bluetooth::Bluetooth(const std::string& id, const Json::Value&
 #ifdef WANT_RFKILL
   rfkill_.on_update.connect(sigc::hide(sigc::mem_fun(*this, &Bluetooth::update)));
 #endif
-  }
 
   dp.emit();
 }
@@ -282,6 +283,41 @@ auto waybar::modules::Bluetooth::update() -> void {
   ALabel::update();
 }
 
+auto waybar::modules::Bluetooth::onObjectAdded(GDBusObjectManager* manager,
+                                               GDBusObject* object,
+                                               gpointer user_data) -> void {
+  ControllerInfo info;
+  Bluetooth* bt = static_cast<Bluetooth*>(user_data);
+
+  if (!bt->cur_controller_.has_value() &&
+      bt->getControllerProperties(object, info) &&
+      (!bt->config_["controller-alias"].isString() ||
+       bt->config_["controller-alias"].asString() == info.alias)) {
+    bt->cur_controller_ = std::move(info);
+    bt->dp.emit();
+  }
+}
+
+auto waybar::modules::Bluetooth::onObjectRemoved(GDBusObjectManager* manager,
+                                                 GDBusObject* object,
+                                                 gpointer user_data) -> void {
+  GDBusProxy* proxy_controller =
+      G_DBUS_PROXY(g_dbus_object_get_interface(object, "org.bluez.Adapter1"));
+
+  if (proxy_controller != NULL) {
+
+    std::string object_path = g_dbus_object_get_object_path(object);
+    Bluetooth* bt = static_cast<Bluetooth*>(user_data);
+
+    if (object_path == bt->cur_controller_->path) {
+      bt->cur_controller_ = bt->findCurController();
+      bt->dp.emit();
+    }
+
+    g_object_unref(proxy_controller);
+  }
+}
+
 // NOTE: only for when the org.bluez.Battery1 interface is added/removed after/before a device is
 // connected/disconnected
 auto waybar::modules::Bluetooth::onInterfaceAddedOrRemoved(GDBusObjectManager* manager,
@@ -292,6 +328,7 @@ auto waybar::modules::Bluetooth::onInterfaceAddedOrRemoved(GDBusObjectManager* m
   std::string object_path = g_dbus_proxy_get_object_path(G_DBUS_PROXY(interface));
   if (interface_name == "org.bluez.Battery1") {
     Bluetooth* bt = static_cast<Bluetooth*>(user_data);
+    if (bt->cur_controller_.has_value()) {
       auto device = std::find_if(bt->connected_devices_.begin(), bt->connected_devices_.end(),
                                  [object_path](auto d) { return d.path == object_path; });
       if (device != bt->connected_devices_.end()) {
@@ -299,6 +336,7 @@ auto waybar::modules::Bluetooth::onInterfaceAddedOrRemoved(GDBusObjectManager* m
         bt->dp.emit();
       }
     }
+  }
 }
 
 auto waybar::modules::Bluetooth::onInterfaceProxyPropertiesChanged(
@@ -309,6 +347,11 @@ auto waybar::modules::Bluetooth::onInterfaceProxyPropertiesChanged(
   std::string object_path = g_dbus_object_get_object_path(G_DBUS_OBJECT(object_proxy));
 
   Bluetooth* bt = static_cast<Bluetooth*>(user_data);
+
+  if (!bt->cur_controller_.has_value()) {
+    return;
+  }
+
   if (interface_name == "org.bluez.Adapter1") {
     if (object_path == bt->cur_controller_->path) {
       bt->getControllerProperties(G_DBUS_OBJECT(object_proxy), *bt->cur_controller_);