firewall: create firewall D-Bus proxy asynchronously

Creating it asynchronously changes that on the first call to
nm_firewall_manager_get() the instance is not yet running.

Note that NMPolicy already connects to the "STARTED" signal and
reapplies the zones when firewalld appears. So, this delayed
change of the running state is handled mostly fine already.

One part is still missing, it's to queue add_or_change/remove calls
while the firewall manager is initializing. That follows next.

(cherry picked from commit 753f39fa826405d4f50793647899059303b0f0cf)

1 files changed, 62 insertions, 26 deletions

diff --git a/src/nm-firewall-manager.c b/src/nm-firewall-manager.c
index 05e5a3f833..cf3d7d79bc 100644
--- a/src/nm-firewall-manager.c
+++ b/src/nm-firewall-manager.c
@@ -40,10 +40,11 @@ enum {
 static guint signals[LAST_SIGNAL] = { 0 };
 
 typedef struct {
-	GDBusProxy *    proxy;
-	gboolean        running;
+	GDBusProxy     *proxy;
+	GCancellable   *proxy_cancellable;
 
 	GHashTable     *pending_calls;
+	bool            running;
 } NMFirewallManagerPrivate;
 
 struct _NMFirewallManager {
@@ -417,14 +418,12 @@ set_running (NMFirewallManager *self, gboolean now_running)
 }
 
 static void
-name_owner_changed (GObject    *object,
-                    GParamSpec *pspec,
-                    gpointer    user_data)
+name_owner_changed (NMFirewallManager *self)
 {
-	NMFirewallManager *self = NM_FIREWALL_MANAGER (user_data);
+	NMFirewallManagerPrivate *priv = NM_FIREWALL_MANAGER_GET_PRIVATE (self);
 	gs_free char *owner = NULL;
 
-	owner = g_dbus_proxy_get_name_owner (G_DBUS_PROXY (object));
+	owner = g_dbus_proxy_get_name_owner (priv->proxy);
 	if (owner) {
 		_LOGD (NULL, "firewall started");
 		set_running (self, TRUE);
@@ -435,6 +434,49 @@ name_owner_changed (GObject    *object,
 	}
 }
 
+static void
+name_owner_changed_cb (GObject    *object,
+                       GParamSpec *pspec,
+                       gpointer    user_data)
+{
+	nm_assert (NM_IS_FIREWALL_MANAGER (user_data));
+	nm_assert (G_IS_DBUS_PROXY (object));
+	nm_assert (NM_FIREWALL_MANAGER_GET_PRIVATE (NM_FIREWALL_MANAGER (user_data))->proxy == G_DBUS_PROXY (object));
+
+	name_owner_changed (NM_FIREWALL_MANAGER (user_data));
+}
+
+static void
+_proxy_new_cb (GObject *source_object,
+               GAsyncResult *result,
+               gpointer user_data)
+{
+	NMFirewallManager *self;
+	NMFirewallManagerPrivate *priv;
+	GDBusProxy *proxy;
+	gs_free_error GError *error = NULL;
+
+	proxy = g_dbus_proxy_new_for_bus_finish (result, &error);
+	if (   !proxy
+	    && g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
+		return;
+
+	self = user_data;
+	priv = NM_FIREWALL_MANAGER_GET_PRIVATE (self);
+	g_clear_object (&priv->proxy_cancellable);
+
+	if (!proxy) {
+		_LOGW (NULL, "could not connect to system D-Bus (%s)", error->message);
+		return;
+	}
+
+	priv->proxy = proxy;
+	g_signal_connect (priv->proxy, "notify::g-name-owner",
+	                  G_CALLBACK (name_owner_changed_cb), self);
+
+	name_owner_changed (self);
+}
+
 /*****************************************************************************/
 
 static void
@@ -465,28 +507,21 @@ constructed (GObject *object)
 {
 	NMFirewallManager *self = (NMFirewallManager *) object;
 	NMFirewallManagerPrivate *priv = NM_FIREWALL_MANAGER_GET_PRIVATE (self);
-	gs_free char *owner = NULL;
-	gs_free_error GError *error = NULL;
 
-	G_OBJECT_CLASS (nm_firewall_manager_parent_class)->constructed (object);
+	priv->proxy_cancellable = g_cancellable_new ();
 
-	priv->proxy = g_dbus_proxy_new_for_bus_sync (G_BUS_TYPE_SYSTEM,
-	                                             G_DBUS_PROXY_FLAGS_DO_NOT_LOAD_PROPERTIES |
-	                                                 G_DBUS_PROXY_FLAGS_DO_NOT_CONNECT_SIGNALS,
-	                                             NULL,
-	                                             FIREWALL_DBUS_SERVICE,
-	                                             FIREWALL_DBUS_PATH,
-	                                             FIREWALL_DBUS_INTERFACE_ZONE,
-	                                             NULL, &error);
-	if (priv->proxy) {
-		g_signal_connect (priv->proxy, "notify::g-name-owner",
-		                  G_CALLBACK (name_owner_changed), self);
-		owner = g_dbus_proxy_get_name_owner (priv->proxy);
-		priv->running = (owner != NULL);
-	} else
-		_LOGW (NULL, "could not connect to system D-Bus (%s)", error->message);
+	g_dbus_proxy_new_for_bus (G_BUS_TYPE_SYSTEM,
+	                            G_DBUS_PROXY_FLAGS_DO_NOT_LOAD_PROPERTIES
+	                          | G_DBUS_PROXY_FLAGS_DO_NOT_CONNECT_SIGNALS,
+	                          NULL,
+	                          FIREWALL_DBUS_SERVICE,
+	                          FIREWALL_DBUS_PATH,
+	                          FIREWALL_DBUS_INTERFACE_ZONE,
+	                          priv->proxy_cancellable,
+	                          _proxy_new_cb,
+	                          self);
 
-	_LOGD (NULL, "firewall constructed (%srunning)", priv->running ? "" : "not");
+	G_OBJECT_CLASS (nm_firewall_manager_parent_class)->constructed (object);
 }
 
 static void
@@ -503,6 +538,7 @@ dispose (GObject *object)
 		priv->pending_calls = NULL;
 	}
 
+	nm_clear_g_cancellable (&priv->proxy_cancellable);
 	g_clear_object (&priv->proxy);
 
 	G_OBJECT_CLASS (nm_firewall_manager_parent_class)->dispose (object);