manager: don't use platform singleton but keep a private pointer

We should reduce uses of singletons in general. Instead, the platform
instance should be passed around and kept for as long as it's needed.

Especially, as we subscribe platform_link_cb() signal. Currently, we
never unsubscribe it (wrongly). Subscribing signals is a strong
indication that the target object should keep the source object alive
until the signal is unsubscribed.

src/nm-manager.c

@@ -110,6 +110,8 @@ typedef struct {
 } RadioState;
 
 typedef struct {
+	NMPlatform *platform;
+
 	GArray *capabilities;
 
 	GSList *active_connections;
@@ -1780,14 +1782,14 @@ get_existing_connection (NMManager *self,
 	nm_device_capture_initial_config (device);
 
 	if (ifindex) {
-		int master_ifindex = nm_platform_link_get_master (NM_PLATFORM_GET, ifindex);
+		int master_ifindex = nm_platform_link_get_master (priv->platform, ifindex);
 
 		if (master_ifindex) {
 			master = nm_manager_get_device_by_ifindex (self, master_ifindex);
 			if (!master) {
 				_LOG2D (LOGD_DEVICE, device, "assume: don't assume because "
 				        "cannot generate connection for slave before its master (%s/%d)",
-				        nm_platform_link_get_name (NM_PLATFORM_GET, master_ifindex), master_ifindex);
+				        nm_platform_link_get_name (priv->platform, master_ifindex), master_ifindex);
 				return NULL;
 			}
 			if (!nm_device_get_act_request (master)) {
@@ -2444,14 +2446,17 @@ static gboolean
 _platform_link_cb_idle (PlatformLinkCbData *data)
 {
 	NMManager *self = data->self;
+	NMManagerPrivate *priv;
 	const NMPlatformLink *l;
 
 	if (!self)
 		goto out;
 
+	priv = NM_MANAGER_GET_PRIVATE (self);
+
 	g_object_remove_weak_pointer (G_OBJECT (self), (gpointer *) &data->self);
 
-	l = nm_platform_link_get (NM_PLATFORM_GET, data->ifindex);
+	l = nm_platform_link_get (priv->platform, data->ifindex);
 	if (l) {
 		NMPlatformLink pllink;
 
@@ -2511,6 +2516,7 @@ platform_link_cb (NMPlatform *platform,
 static void
 platform_query_devices (NMManager *self)
 {
+	NMManagerPrivate *priv = NM_MANAGER_GET_PRIVATE (self);
 	gs_unref_ptrarray GPtrArray *links = NULL;
 	int i;
 	gboolean guess_assume;
@@ -2521,7 +2527,7 @@ platform_query_devices (NMManager *self)
 	                                         NM_CONFIG_KEYFILE_GROUP_MAIN,
 	                                         NM_CONFIG_KEYFILE_KEY_MAIN_SLAVES_ORDER,
 	                                         NM_CONFIG_GET_VALUE_STRIP);
-	links = nm_platform_link_get_all (NM_PLATFORM_GET, !nm_streq0 (order, "index"));
+	links = nm_platform_link_get_all (priv->platform, !nm_streq0 (order, "index"));
 	if (!links)
 		return;
 	for (i = 0; i < links->len; i++) {
@@ -4169,7 +4175,7 @@ impl_manager_add_and_activate_connection (NMManager *self,
 			goto error;
 		}
 
-		nm_utils_complete_generic (NM_PLATFORM_GET,
+		nm_utils_complete_generic (priv->platform,
 		                           connection,
 		                           NM_SETTING_VPN_SETTING_NAME,
 		                           all_connections,
@@ -4386,9 +4392,9 @@ done:
 }
 
 static gboolean
-device_is_wake_on_lan (NMDevice *device)
+device_is_wake_on_lan (NMPlatform *platform, NMDevice *device)
 {
-	return nm_platform_link_get_wake_on_lan (NM_PLATFORM_GET, nm_device_get_ip_ifindex (device));
+	return nm_platform_link_get_wake_on_lan (platform, nm_device_get_ip_ifindex (device));
 }
 
 static gboolean
@@ -4506,7 +4512,8 @@ do_sleep_wake (NMManager *self, gboolean sleeping_changed)
 			if (nm_device_is_software (device))
 				continue;
 			/* Wake-on-LAN devices will be taken down post-suspend rather than pre- */
-			if (suspending && device_is_wake_on_lan (device)) {
+			if (   suspending
+			    && device_is_wake_on_lan (priv->platform, device)) {
 				_LOGD (LOGD_SUSPEND, "sleep: device %s has wake-on-lan, skipping",
 				       nm_device_get_ip_iface (device));
 				continue;
@@ -4537,7 +4544,7 @@ do_sleep_wake (NMManager *self, gboolean sleeping_changed)
 				/* Belatedly take down Wake-on-LAN devices; ideally we wouldn't have to do this
 				 * but for now it's the only way to make sure we re-check their connectivity.
 				 */
-				if (device_is_wake_on_lan (device))
+				if (device_is_wake_on_lan (priv->platform, device))
 					nm_device_set_unmanaged_by_flags (device, NM_UNMANAGED_SLEEPING, TRUE, NM_DEVICE_STATE_REASON_SLEEPING);
 
 				/* Check if the device is unmanaged but the state transition is still pending.
@@ -5111,7 +5118,7 @@ nm_manager_write_device_state (NMManager *self)
 			continue;
 		}
 
-		if (!nm_platform_link_get (NM_PLATFORM_GET, ifindex))
+		if (!nm_platform_link_get (priv->platform, ifindex))
 			continue;
 
 		managed = nm_device_get_managed (device, FALSE);
@@ -5196,9 +5203,9 @@ nm_manager_start (NMManager *self, GError **error)
 	nm_device_factory_manager_load_factories (_register_device_factory, self);
 	nm_device_factory_manager_for_each_factory (start_factory, NULL);
 
-	nm_platform_process_events (NM_PLATFORM_GET);
+	nm_platform_process_events (priv->platform);
 
-	g_signal_connect (NM_PLATFORM_GET,
+	g_signal_connect (priv->platform,
 	                  NM_PLATFORM_SIGNAL_LINK_CHANGED,
 	                  G_CALLBACK (platform_link_cb),
 	                  self);
@@ -6149,6 +6156,8 @@ nm_manager_init (NMManager *self)
 	guint i;
 	GFile *file;
 
+	priv->platform = g_object_ref (NM_PLATFORM_GET);
+
 	priv->capabilities = g_array_new (FALSE, FALSE, sizeof (guint32));
 
 	/* Initialize rfkill structures and states */
@@ -6480,6 +6489,8 @@ finalize (GObject *object)
 	g_array_free (priv->capabilities, TRUE);
 
 	G_OBJECT_CLASS (nm_manager_parent_class)->finalize (object);
+
+	g_object_unref (priv->platform);
 }
 
 static void