From 9a38c03fe27d0c8f9a026a24c33a4bd414b04e2d Mon Sep 17 00:00:00 2001
From: Richard Hughes <richard@hughsie.com>
Date: Tue, 17 Mar 2015 20:58:46 +0000
Subject: [PATCH] Do not crash when there are no devices to return

---
 src/fu-main.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/src/fu-main.c b/src/fu-main.c
index 1f559af90..ca1efa5f2 100644
--- a/src/fu-main.c
+++ b/src/fu-main.c
@@ -137,11 +137,20 @@ fu_main_set_status (FuMainPrivate *priv, FuStatus status)
  * fu_main_device_array_to_variant:
  **/
 static GVariant *
-fu_main_device_array_to_variant (FuMainPrivate *priv)
+fu_main_device_array_to_variant (FuMainPrivate *priv, GError **error)
 {
 	GVariantBuilder builder;
 	guint i;
 
+	/* no devices */
+	if (priv->devices->len == 0) {
+		g_set_error_literal (error,
+				     FU_ERROR,
+				     FU_ERROR_NOTHING_TO_DO,
+				     "no supported devices");
+		return NULL;
+	}
+
 	g_variant_builder_init (&builder, G_VARIANT_TYPE_ARRAY);
 	for (i = 0; i < priv->devices->len; i++) {
 		GVariant *tmp;
@@ -456,9 +465,14 @@ fu_main_daemon_method_call (GDBusConnection *connection, const gchar *sender,
 
 	/* return 'as' */
 	if (g_strcmp0 (method_name, "GetDevices") == 0) {
+		_cleanup_error_free_ GError *error = NULL;
 		_cleanup_strv_free_ gchar **devices = NULL;
 		g_debug ("Called %s()", method_name);
-		val = fu_main_device_array_to_variant (priv);
+		val = fu_main_device_array_to_variant (priv, &error);
+		if (val == NULL) {
+			g_dbus_method_invocation_return_gerror (invocation, error);
+			return;
+		}
 		g_dbus_method_invocation_return_value (invocation, val);
 		fu_main_set_status (priv, FU_STATUS_IDLE);
 		return;