core: better order the code at startup

NM was calling nm_bus_manager_start_service() to claim its bus name
before it exported any of its objects, but this didn't matter under
dbus-glib, because no client connections would be accepted until the
main loop was started later on, by which point we would have exported
everything.

But with gdbus, method calls are initially received in the gdbus
worker thread, which means that clients would be able to connect right
away and then be told that the expected interfaces don't exist.

So move the nm_bus_manager_start_service() call to occur after
creating NMSettings and NMManager (and, indirectly, NMAgentManager).
This requires splitting out the slow parts of nm_settings_new() into a
new nm_settings_start(), so that we can create and export it first,
and then read the connections, etc afterward. (Likewise, there were
still a few potentially-slow bits in nm_manager_new() which are now
moved into nm_manager_start().)

src/main.c

@@ -419,6 +419,16 @@ main (int argc, char *argv[])
 #endif
 	             );
 
+	nm_auth_manager_setup (nm_config_get_auth_polkit (config));
+
+	settings = nm_settings_new ();
+	manager = nm_manager_new (settings,
+	                          global_opt.state_file,
+	                          net_enabled,
+	                          wifi_enabled,
+	                          wwan_enabled,
+	                          wimax_enabled);
+
 	if (!nm_bus_manager_get_connection (nm_bus_manager_get ())) {
 #if HAVE_DBUS_GLIB_100
 		nm_log_warn (LOGD_CORE, "Failed to connect to D-Bus; only private bus is available");
@@ -443,24 +453,13 @@ main (int argc, char *argv[])
 	 * NMPlatform. */
 	g_object_ref (NM_PLATFORM_GET);
 
-	nm_auth_manager_setup (nm_config_get_auth_polkit (config));
-
 	nm_dispatcher_init ();
 
-	settings = nm_settings_new (&error);
-	if (!settings) {
-		nm_log_err (LOGD_CORE, "failed to initialize settings storage: %s",
-		            error && error->message ? error->message : "(unknown)");
+	if (!nm_settings_start (settings, &error)) {
+		nm_log_err (LOGD_CORE, "failed to initialize settings storage: %s", error->message);
 		goto done;
 	}
 
-	manager = nm_manager_new (settings,
-	                          global_opt.state_file,
-	                          net_enabled,
-	                          wifi_enabled,
-	                          wwan_enabled,
-	                          wimax_enabled);
-
 	g_signal_connect (manager, NM_MANAGER_CONFIGURE_QUIT, G_CALLBACK (manager_configure_quit), config);
 
 	nm_manager_start (manager);

src/nm-manager.c

@@ -4198,6 +4198,11 @@ nm_manager_start (NMManager *self)
 	NMManagerPrivate *priv = NM_MANAGER_GET_PRIVATE (self);
 	guint i;
 
+	g_signal_connect (nm_platform_get (),
+	                  NM_PLATFORM_SIGNAL_LINK_CHANGED,
+	                  G_CALLBACK (platform_link_cb),
+	                  self);
+
 	/* Set initial radio enabled/disabled state */
 	for (i = 0; i < RFKILL_TYPE_MAX; i++) {
 		RadioState *rstate = &priv->radio_states[i];
@@ -4227,10 +4232,14 @@ nm_manager_start (NMManager *self)
 	system_hostname_changed_cb (priv->settings, NULL, self);
 
 	/* Start device factories */
+	nm_device_factory_manager_load_factories (_register_device_factory, self);
 	nm_device_factory_manager_for_each_factory (start_factory, NULL);
 
 	platform_query_devices (self);
 
+	/* Load VPN plugins */
+	priv->vpn_manager = g_object_ref (nm_vpn_manager_get ());
+
 	/*
 	 * Connections added before the manager is started do not emit
 	 * connection-added signals thus devices have to be created manually.
@@ -4831,11 +4840,6 @@ nm_manager_new (NMSettings *settings,
 
 	nm_exported_object_export (NM_EXPORTED_OBJECT (singleton));
 
-	g_signal_connect (nm_platform_get (),
-	                  NM_PLATFORM_SIGNAL_LINK_CHANGED,
-	                  G_CALLBACK (platform_link_cb),
-	                  singleton);
-
 	priv->rfkill_mgr = nm_rfkill_manager_new ();
 	g_signal_connect (priv->rfkill_mgr,
 	                  "rfkill-changed",
@@ -4850,8 +4854,6 @@ nm_manager_new (NMSettings *settings,
 	rfkill_change (priv->radio_states[RFKILL_TYPE_WLAN].desc, RFKILL_TYPE_WLAN, initial_wifi_enabled);
 	rfkill_change (priv->radio_states[RFKILL_TYPE_WWAN].desc, RFKILL_TYPE_WWAN, initial_wwan_enabled);
 
-	nm_device_factory_manager_load_factories (_register_device_factory, singleton);
-
 	return singleton;
 }
 
@@ -4899,8 +4901,6 @@ nm_manager_init (NMManager *manager)
 	                  G_CALLBACK (dbus_connection_changed_cb),
 	                  manager);
 
-	priv->vpn_manager = g_object_ref (nm_vpn_manager_get ());
-
 	/* sleep/wake handling */
 	priv->sleep_monitor = g_object_ref (nm_sleep_monitor_get ());
 	g_signal_connect (priv->sleep_monitor, NM_SLEEP_MONITOR_SLEEPING,

src/settings/nm-settings.c

@@ -176,6 +176,7 @@ typedef struct {
 	GSList *unrecognized_specs;
 	GSList *get_connections_cache;
 
+	gboolean started;
 	gboolean startup_complete;
 
 	struct {
@@ -561,6 +562,9 @@ nm_settings_get_hostname (NMSettings *self)
 	NMSettingsPrivate *priv = NM_SETTINGS_GET_PRIVATE (self);
 	char *hostname = NULL;
 
+	if (!priv->started)
+		return NULL;
+
 	if (priv->hostname.hostnamed_proxy) {
 		hostname = g_strdup (priv->hostname.value);
 		goto out;
@@ -2094,13 +2098,10 @@ setup_hostname_file_monitors (NMSettings *self)
 }
 
 NMSettings *
-nm_settings_new (GError **error)
+nm_settings_new (void)
 {
 	NMSettings *self;
 	NMSettingsPrivate *priv;
-	GDBusProxy *proxy;
-	GVariant *variant;
-	GError *local_error = NULL;
 
 	self = g_object_new (NM_TYPE_SETTINGS, NULL);
 
@@ -2109,10 +2110,24 @@ nm_settings_new (GError **error)
 	priv->config = nm_config_get ();
 	priv->dbus_mgr = nm_bus_manager_get ();
 
+	nm_exported_object_export (NM_EXPORTED_OBJECT (self));
+	return self;
+}
+
+gboolean
+nm_settings_start (NMSettings *self, GError **error)
+{
+	NMSettingsPrivate *priv;
+	GDBusProxy *proxy;
+	GVariant *variant;
+	GError *local_error = NULL;
+
+	priv = NM_SETTINGS_GET_PRIVATE (self);
+
 	/* Load the plugins; fail if a plugin is not found. */
 	if (!load_plugins (self, nm_config_get_plugins (priv->config), error)) {
 		g_object_unref (self);
-		return NULL;
+		return FALSE;
 	}
 
 	load_connections (self);
@@ -2143,8 +2158,9 @@ nm_settings_new (GError **error)
 	if (!priv->hostname.hostnamed_proxy)
 		setup_hostname_file_monitors (self);
 
-	nm_exported_object_export (NM_EXPORTED_OBJECT (self));
-	return self;
+	priv->started = TRUE;
+	g_object_notify (G_OBJECT (self), NM_SETTINGS_HOSTNAME);
+	return TRUE;
 }
 
 static void

src/settings/nm-settings.h

@@ -73,7 +73,8 @@ typedef struct {
 
 GType nm_settings_get_type (void);
 
-NMSettings *nm_settings_new (GError **error);
+NMSettings *nm_settings_new (void);
+gboolean nm_settings_start (NMSettings *self, GError **error);
 
 typedef void (*NMSettingsForEachFunc) (NMSettings *settings,
                                        NMSettingsConnection *connection,