[PATCH BlueZ 2/2] core/device: Implement GattServices property

[Arman Uguray <armansito@chromium.org>]

This patch implements the new GattServices property, which gets updated
when a device's associated bt_gatt_client becomes ready.
---
 src/device.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 74 insertions(+), 2 deletions(-)

diff --git a/src/device.c b/src/device.c
index 8b678a9..d4d72c0 100644
--- a/src/device.c
+++ b/src/device.c
@@ -233,6 +233,7 @@ struct btd_device {
 	 * attribute cache support can be built.
 	 */
 	struct gatt_db *db;			/* GATT db cache */
+	bool gatt_cache_used;			/* true if discovery skipped */
 	struct bt_gatt_client *client;		/* GATT client instance */
 	struct bt_gatt_server *server;		/* GATT server instance */
 
@@ -546,8 +547,11 @@ static void gatt_client_cleanup(struct btd_device *device)
 	 * the bonding state for the correct bearer based on the transport over
 	 * which GATT is being done.
 	 */
-	if (!device->le_state.bonded)
-		gatt_db_clear(device->db);
+	if (device->le_state.bonded)
+		return;
+
+	gatt_db_clear(device->db);
+	device->gatt_cache_used = false;
 }
 
 static void gatt_server_cleanup(struct btd_device *device)
@@ -948,6 +952,42 @@ static gboolean dev_property_exists_tx_power(const GDBusPropertyTable *property,
 	return TRUE;
 }
 
+static void append_service_path(const char *path, void *user_data)
+{
+	DBusMessageIter *array = user_data;
+
+	dbus_message_iter_append_basic(array, DBUS_TYPE_OBJECT_PATH, &path);
+}
+
+static gboolean dev_property_get_gatt_services(
+					const GDBusPropertyTable *property,
+					DBusMessageIter *iter, void *data)
+{
+	struct btd_device *dev = data;
+	DBusMessageIter array;
+
+	dbus_message_iter_open_container(iter, DBUS_TYPE_ARRAY, "o", &array);
+
+	btd_gatt_client_foreach_service(dev->client_dbus, append_service_path,
+									&array);
+
+	dbus_message_iter_close_container(iter, &array);
+
+	return TRUE;
+}
+
+static gboolean dev_property_exists_gatt_services(
+					const GDBusPropertyTable *property,
+					void *data)
+{
+	struct btd_device *dev = data;
+
+	if (!dev->client || !bt_gatt_client_is_ready(dev->client))
+		return FALSE;
+
+	return TRUE;
+}
+
 static gboolean dev_property_get_trusted(const GDBusPropertyTable *property,
 					DBusMessageIter *iter, void *data)
 {
@@ -2331,6 +2371,9 @@ static const GDBusPropertyTable device_properties[] = {
 	{ "TxPower", "n", dev_property_get_tx_power, NULL,
 					dev_property_exists_tx_power,
 					G_DBUS_PROPERTY_FLAG_EXPERIMENTAL },
+	{ "GattServices", "ao", dev_property_get_gatt_services, NULL,
+					dev_property_exists_gatt_services,
+					G_DBUS_PROPERTY_FLAG_EXPERIMENTAL },
 
 	{ }
 };
@@ -2927,6 +2970,16 @@ static void device_remove_gatt_profile(struct btd_device *device,
 	service_remove(service);
 }
 
+static gboolean gatt_services_changed(gpointer user_data)
+{
+	struct btd_device *device = user_data;
+
+	g_dbus_emit_property_changed(dbus_conn, device->path, DEVICE_INTERFACE,
+								"GattServices");
+
+	return FALSE;
+}
+
 static void gatt_service_added(struct gatt_db_attribute *attr, void *user_data)
 {
 	struct btd_device *device = user_data;
@@ -2971,6 +3024,8 @@ static void gatt_service_added(struct gatt_db_attribute *attr, void *user_data)
 	store_device_info(device);
 
 	btd_gatt_client_service_added(device->client_dbus, attr);
+
+	gatt_services_changed(device);
 }
 
 static gint prim_attr_cmp(gconstpointer a, gconstpointer b)
@@ -3058,6 +3113,8 @@ static void gatt_service_removed(struct gatt_db_attribute *attr,
 	store_device_info(device);
 
 	btd_gatt_client_service_removed(device->client_dbus, attr);
+
+	gatt_services_changed(device);
 }
 
 static struct btd_device *device_new(struct btd_adapter *adapter,
@@ -4147,6 +4204,19 @@ static void gatt_client_ready_cb(bool success, uint8_t att_ecode,
 	device_accept_gatt_profiles(device);
 
 	btd_gatt_client_ready(device->client_dbus);
+
+	/*
+	 * Update the GattServices property. Do this asynchronously since this
+	 * should happen after the "Characteristics" and "Descriptors"
+	 * properties of all services have been asynchronously updated by
+	 * btd_gatt_client.
+	 *
+	 * Service discovery will be skipped and exported objects won't change
+	 * if the attribute cache was populated when bt_gatt_client gets
+	 * initialized, so no need to to send this signal if that's the case.
+	 */
+	if (!device->gatt_cache_used)
+		g_idle_add(gatt_services_changed, device);
 }
 
 static void gatt_client_service_changed(uint16_t start_handle,
@@ -4192,6 +4262,8 @@ static void gatt_client_init(struct btd_device *device)
 		gatt_client_cleanup(device);
 		return;
 	}
+
+	device->gatt_cache_used = !gatt_db_isempty(device->db);
 }
 
 static void gatt_server_init(struct btd_device *device, struct gatt_db *db)
-- 
2.2.0.rc0.207.ga3a616c