Merge pull request #504 from jonls/geoclue-update

GeoClue: better error message when access is denied

2 files changed, 43 insertions, 7 deletions

diff --git a/README.md b/README.md
index 890732d..65899e3 100644
--- a/README.md
+++ b/README.md
@@ -25,7 +25,9 @@ FAQ
 
 **How do I install Redshift?**
 
-Use the packages provided by your distribution, e.g. for Ubuntu: `apt-get install redshift` or `apt-get install redshift-gtk`. For developers, please see _Building from source_ and _Latest builds from master branch_ below.
+Use the packages provided by your distribution, e.g. for Ubuntu:
+`apt-get install redshift` or `apt-get install redshift-gtk`. For developers,
+please see _Building from source_ and _Latest builds from master branch_ below.
 
 **How do I setup a configuration file?**
 
@@ -48,6 +50,18 @@ example clicking anywhere on Google Maps will bring up a box with the
 coordinates. Remember that longitudes in the western hemisphere (e.g. the
 Americas) must be provided to Redshift as negative numbers.
 
+**Why does GeoClue fail with access denied error?**
+
+It is possible that the location services have been disabled completely. The
+check for this case varies by desktop environment. For example, in GNOME the
+location services can be toggled in Settings > Privacy > Location Services.
+
+If this is not the case, it is possible that Redshift has been improperly
+installed or not been given the required permissions to obtain location
+updates from a system administrator. See
+https://github.com/jonls/redshift/issues/318 for further discussion on this
+issue.
+
 **Why doesn't Redshift work on my Chromebook/Raspberry Pi?**
 
 Certain video drivers do not support adjustable gamma ramps. In some cases
diff --git a/src/location-geoclue2.c b/src/location-geoclue2.c
index 9641507..6ebedb4 100644
--- a/src/location-geoclue2.c
+++ b/src/location-geoclue2.c
@@ -35,6 +35,20 @@
 # define _(s) s
 #endif
 
+#define DBUS_ACCESS_ERROR  "org.freedesktop.DBus.Error.AccessDenied"
+
+
+/* Print the message explaining denial from GeoClue. */
+static void
+print_denial_message()
+{
+	g_printerr(_(
+		"Access to the current location was denied by GeoClue!\n"
+		"Make sure that location services are enabled and that"
+		" Redshift is permitted\nto use location services."
+		" See https://github.com/jonls/redshift#faq for more\n"
+		"information.\n"));
+}
 
 /* Indicate an unrecoverable error during GeoClue2 communication. */
 static void
@@ -68,8 +82,8 @@ geoclue_client_signal_cb(GDBusProxy *client, gchar *sender_name,
 
 	/* Obtain location */
 	GError *error = NULL;
-	GDBusProxy *location = g_dbus_proxy_new_for_bus_sync(
-		G_BUS_TYPE_SYSTEM,
+	GDBusProxy *location = g_dbus_proxy_new_sync(
+		g_dbus_proxy_get_connection(client),
 		G_DBUS_PROXY_FLAGS_NONE,
 		NULL,
 		"org.freedesktop.GeoClue2",
@@ -111,8 +125,8 @@ on_name_appeared(GDBusConnection *conn, const gchar *name,
 
 	/* Obtain GeoClue Manager */
 	GError *error = NULL;
-	GDBusProxy *geoclue_manager = g_dbus_proxy_new_for_bus_sync(
-		G_BUS_TYPE_SYSTEM,
+	GDBusProxy *geoclue_manager = g_dbus_proxy_new_sync(
+		conn,
 		G_DBUS_PROXY_FLAGS_NONE,
 		NULL,
 		"org.freedesktop.GeoClue2",
@@ -149,8 +163,8 @@ on_name_appeared(GDBusConnection *conn, const gchar *name,
 
 	/* Obtain GeoClue client */
 	error = NULL;
-	GDBusProxy *geoclue_client = g_dbus_proxy_new_for_bus_sync(
-		G_BUS_TYPE_SYSTEM,
+	GDBusProxy *geoclue_client = g_dbus_proxy_new_sync(
+		conn,
 		G_DBUS_PROXY_FLAGS_NONE,
 		NULL,
 		"org.freedesktop.GeoClue2",
@@ -225,6 +239,14 @@ on_name_appeared(GDBusConnection *conn, const gchar *name,
 	if (ret_v == NULL) {
 		g_printerr(_("Unable to start GeoClue client: %s.\n"),
 			   error->message);
+		if (g_dbus_error_is_remote_error(error)) {
+			gchar *dbus_error = g_dbus_error_get_remote_error(
+				error);
+			if (g_strcmp0(dbus_error, DBUS_ACCESS_ERROR) == 0) {
+				print_denial_message();
+			}
+			g_free(dbus_error);
+		}
 		g_error_free(error);
 		g_object_unref(geoclue_client);
 		g_object_unref(geoclue_manager);