attempt handling invalid bus address settings

If the bus address is set to an invalid path, we will get the file not
found error from GIO when connecting to a bus. This might occur very
rarely in environments where there is no system bus (like my test
environment currently) or where the user has set the
DBUS_SESSION_BUS_ADDRESS environment variable to an incorrect value. I
don't believe the first case will ever occur for a normal user, and in
the second case, it is almost certainly user error. So we might just
settle on logging a warning and pretending the bus doesn't exist.

playerctl/playerctl-player-manager.c

@@ -374,8 +374,13 @@ static gboolean playerctl_player_manager_initable_init(GInitable *initable,
                                       "org.freedesktop.DBus", NULL,
                                       &tmp_error);
     if (tmp_error != NULL) {
-        g_propagate_error(error, tmp_error);
+        if (tmp_error->domain == G_IO_ERROR && tmp_error->code == G_IO_ERROR_NOT_FOUND) {
-        return FALSE;
+            // TODO the bus address was set incorrectly so log a warning
+            g_clear_error(&tmp_error);
+        } else {
+            g_propagate_error(error, tmp_error);
+            return FALSE;
+        }
     }
     manager->priv->system_proxy =
         g_dbus_proxy_new_for_bus_sync(G_BUS_TYPE_SYSTEM,
@@ -385,8 +390,13 @@ static gboolean playerctl_player_manager_initable_init(GInitable *initable,
                                       "org.freedesktop.DBus", NULL,
                                       &tmp_error);
     if (tmp_error != NULL) {
-        g_propagate_error(error, tmp_error);
+        if (tmp_error->domain == G_IO_ERROR && tmp_error->code == G_IO_ERROR_NOT_FOUND) {
-        return FALSE;
+            // TODO the bus address was set incorrectly so log a warning
+            g_clear_error(&tmp_error);
+        } else {
+            g_propagate_error(error, tmp_error);
+            return FALSE;
+        }
     }
 
     manager->priv->player_names = playerctl_list_players(&tmp_error);
@@ -395,12 +405,17 @@ static gboolean playerctl_player_manager_initable_init(GInitable *initable,
         return FALSE;
     }
 
-    g_signal_connect(G_DBUS_PROXY(manager->priv->session_proxy), "g-signal",
+    if (manager->priv->session_proxy) {
-                     G_CALLBACK(dbus_name_owner_changed_callback),
+        g_signal_connect(G_DBUS_PROXY(manager->priv->session_proxy), "g-signal",
-                     manager);
+                G_CALLBACK(dbus_name_owner_changed_callback),
-    g_signal_connect(G_DBUS_PROXY(manager->priv->system_proxy), "g-signal",
+                manager);
-                     G_CALLBACK(dbus_name_owner_changed_callback),
+    }
-                     manager);
+
+    if (manager->priv->system_proxy) {
+        g_signal_connect(G_DBUS_PROXY(manager->priv->system_proxy), "g-signal",
+                G_CALLBACK(dbus_name_owner_changed_callback),
+                manager);
+    }
 
     manager->priv->initted = TRUE;
 

playerctl/playerctl-player.c

@@ -859,6 +859,15 @@ static GList *list_player_names_on_bus(GBusType bus_type, GError **err) {
         "/org/freedesktop/DBus", "org.freedesktop.DBus", NULL, &tmp_error);
 
     if (tmp_error != NULL) {
+        if (tmp_error->domain == G_IO_ERROR && tmp_error->code == G_IO_ERROR_NOT_FOUND) {
+            // XXX: This means the dbus socket address is not found which may
+            // mean that the bus is not running or the address was set
+            // incorrectly. I think we can pass through here because it is true
+            // that there are no names on the bus that is supposed to be at
+            // this socket path. But we need a better way of dealing with this case.
+            g_clear_error(&tmp_error);
+            return NULL;
+        }
         g_propagate_error(err, tmp_error);
         return NULL;
     }
@@ -1001,6 +1010,11 @@ static gboolean playerctl_player_initable_init(GInitable *initable,
                 bus_name_for_player_name(player->priv->player_name,
                         bus_types[i], &tmp_error);
             if (tmp_error != NULL) {
+                if (tmp_error->domain == G_IO_ERROR && tmp_error->code == G_IO_ERROR_NOT_FOUND) {
+                    // TODO the bus address was set incorrectly so log a warning
+                    g_clear_error(&tmp_error);
+                    continue;
+                }
                 g_propagate_error(err, tmp_error);
                 return FALSE;
             }