bugfix: only sort non-NULL array

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

src/garmin.c

@@ -98,7 +98,7 @@ garmin_device_open (dc_device_t **out, dc_context_t *context, dc_iostream_t *ios
 	// for a Descent Mk2/Mk2i, we have to use MTP to access its storage;
 	// for Garmin devices, the model number corresponds to the lower three nibbles of the USB product ID
 	// in order to have only one entry for the Mk2, we don't use the Mk2/APAC model number in our code
-	device->use_mtp = (model == 0x0FFF & DESCENT_MK2);
+	device->use_mtp = (model == (0x0FFF & DESCENT_MK2));
 	DEBUG(context, "Found Garmin with model 0x%x which is a %s\n", model, (device->use_mtp ? "Mk2/Mk2i" : "Mk1"));
 #endif
 
@@ -322,7 +322,8 @@ mtp_get_file_list(dc_device_t *abstract, struct file_list *files)
 	free(rawdevices);
 	DEBUG(abstract->context, "Found %d files", files->nr);
 
-	qsort(files->array, files->nr, sizeof(struct fit_file), name_cmp);
+	if (files->array)
+		qsort(files->array, files->nr, sizeof(struct fit_file), name_cmp);
 	return DC_STATUS_SUCCESS;
 }