gattlib: Introduce 'gattlib_register_on_disconnect()'

dbus/gattlib.c

@@ -220,7 +220,8 @@ gboolean on_handle_device_property_change(
 	    const gchar *const *arg_invalidated_properties,
 	    gpointer user_data)
 {
-	GMainLoop *loop = user_data;
+	gatt_connection_t* connection = user_data;
+	gattlib_context_t* conn_context = connection->context;
 
 	// Retrieve 'Value' from 'arg_changed_properties'
 	if (g_variant_n_children (arg_changed_properties) > 0) {
@@ -231,8 +232,16 @@ gboolean on_handle_device_property_change(
 		g_variant_get (arg_changed_properties, "a{sv}", &iter);
 		while (g_variant_iter_loop (iter, "{&sv}", &key, &value)) {
 			if (strcmp(key, "UUIDs") == 0) {
-				g_main_loop_quit(loop);
+				// When UUIDs properties appear, we are connected to the device
+				g_main_loop_quit(conn_context->connection_loop);
 				break;
+			} else if (strcmp(key, "Connected") == 0) {
+				if (!g_variant_get_boolean(value)) {
+					// Disconnection case
+					if (connection->disconnection_handler) {
+						connection->disconnection_handler(connection->disconnection_user_data);
+					}
+				}
 			}
 		}
 	}
@@ -316,17 +325,19 @@ gatt_connection_t *gattlib_connect(const char *src, const char *dst,
 
 	// Wait for the property 'UUIDs' to be changed. We assume 'org.bluez.GattService1
 	// and 'org.bluez.GattCharacteristic1' to be advertised at that moment.
-	GMainLoop *loop = g_main_loop_new(NULL, 0);
+	conn_context->connection_loop = g_main_loop_new(NULL, 0);
 
 	// Register a handle for notification
 	g_signal_connect(device,
 		"g-properties-changed",
 		G_CALLBACK (on_handle_device_property_change),
-		loop);
+		connection);
 
-	g_timeout_add_seconds (CONNECT_TIMEOUT, stop_scan_func, loop);
+	g_timeout_add_seconds (CONNECT_TIMEOUT, stop_scan_func, conn_context->connection_loop);
-	g_main_loop_run(loop);
+	g_main_loop_run(conn_context->connection_loop);
-	g_main_loop_unref(loop);
+	g_main_loop_unref(conn_context->connection_loop);
+	// Set the attribute to NULL even if not required
+	conn_context->connection_loop = NULL;
 
 	return connection;
 
@@ -364,6 +375,11 @@ int gattlib_disconnect(gatt_connection_t* connection) {
 	return 0;
 }
 
+void gattlib_register_on_disconnect(gatt_connection_t *connection, gattlib_disconnection_handler_t handler, void* user_data) {
+	connection->disconnection_handler = handler;
+	connection->disconnection_user_data = user_data;
+}
+
 // Bluez was using org.bluez.Device1.GattServices until 5.37 to expose the list of available GATT Services
 #if BLUEZ_VERSION < BLUEZ_VERSIONS(5, 38)
 int gattlib_discover_primary(gatt_connection_t* connection, gattlib_primary_service_t** services, int* services_count) {

dbus/gattlib_internal.h

@@ -41,6 +41,10 @@
 typedef struct {
 	char* device_object_path;
 	OrgBluezDevice1* device;
+
+	// This attribute is only used during the connection stage. By placing the attribute here, we can pass
+	// `gatt_connection_t` to
+	GMainLoop *connection_loop;
 } gattlib_context_t;
 
 #endif

include/gattlib.h

@@ -69,6 +69,14 @@ typedef struct _GAttrib GAttrib;
 
 typedef void (*gattlib_event_handler_t)(const uuid_t* uuid, const uint8_t* data, size_t data_length, void* user_data);
 
+/**
+ * @brief Handler called on disconnection
+ *
+ * @param connection Connection that is disconnecting
+ * @param user_data  Data defined when calling `gattlib_register_on_disconnect()`
+ */
+typedef void (*gattlib_disconnection_handler_t)(void* user_data);
+
 typedef struct _gatt_connection_t {
 	void* context;
 
@@ -77,17 +85,19 @@ typedef struct _gatt_connection_t {
 
 	gattlib_event_handler_t indication_handler;
 	void* indication_user_data;
+
+	gattlib_disconnection_handler_t disconnection_handler;
+	void* disconnection_user_data;
 } gatt_connection_t;
 
 typedef void (*gattlib_discovered_device_t)(const char* addr, const char* name);
 typedef void (*gatt_connect_cb_t)(gatt_connection_t* connection, void* user_data);
 typedef void* (*gatt_read_cb_t)(const void* buffer, size_t buffer_len);
 
-
 /**
- * Open Bluetooth adapter
+ * @brief Open Bluetooth adapter
  *
- * @adapter_name    With value NULL, the default adapter will be selected.
+ * @param adapter_name    With value NULL, the default adapter will be selected.
  */
 int gattlib_adapter_open(const char* adapter_name, void** adapter);
 int gattlib_adapter_scan_enable(void* adapter, gattlib_discovered_device_t discovered_device_cb, int timeout);
@@ -111,6 +121,8 @@ gatt_connection_t *gattlib_connect_async(const char *src, const char *dst,
 
 int gattlib_disconnect(gatt_connection_t* connection);
 
+void gattlib_register_on_disconnect(gatt_connection_t *connection, gattlib_disconnection_handler_t handler, void* user_data);
+
 typedef struct {
 	uint16_t  attr_handle_start;
 	uint16_t  attr_handle_end;