Properly chain-up GTasks around GDBusProxy::init_async

Our GAsyncInitable implementations in SecretService, SecretCollection,
and SecretItem internally wrap GDBusProxy::init_async and perform
additional error processing. To chain up we used to pass around a
single GTask, which caused an issue in the (additional) error path:
GDBusProxy::init_async may have already called
g_task_return_boolean(task, TRUE) and in that case GLib produces the
following warning:

  g_task_return_error: assertion '!task->ever_returned' failed

This fixes the issue by creating a temporary GTask around
GDBusProxy::init_async call.

Signed-off-by: Daiki Ueno <dueno@src.gnome.org>

libsecret/secret-collection.c

@@ -625,17 +625,35 @@ on_init_service (GObject *source,
 	g_clear_object (&task);
 }
 
+typedef struct {
+	GAsyncReadyCallback callback;
+	gpointer user_data;
+} InitBaseClosure;
+
+static void
+secret_collection_async_initable_init_async (GAsyncInitable *initable,
+                                             int io_priority,
+                                             GCancellable *cancellable,
+                                             GAsyncReadyCallback callback,
+                                             gpointer user_data);
+
 static void
 on_init_base (GObject *source,
               GAsyncResult *result,
               gpointer user_data)
 {
-	GTask *task = G_TASK (user_data);
+	GTask *base_task = G_TASK (user_data);
-	GCancellable *cancellable = g_task_get_cancellable (task);
+	InitBaseClosure *base = g_task_get_task_data (base_task);
+	GCancellable *cancellable = g_task_get_cancellable (base_task);
+	GTask *task;
 	SecretCollection *self = SECRET_COLLECTION (source);
 	GDBusProxy *proxy = G_DBUS_PROXY (self);
 	GError *error = NULL;
 
+	task = g_task_new (source, cancellable, base->callback, base->user_data);
+	g_task_set_source_tag (task, secret_collection_async_initable_init_async);
+	g_clear_object (&base_task);
+
 	if (!secret_collection_async_initable_parent_iface->init_finish (G_ASYNC_INITABLE (self),
 	                                                                 result, &error)) {
 		g_task_return_error (task, g_steal_pointer (&error));
@@ -665,10 +683,16 @@ secret_collection_async_initable_init_async (GAsyncInitable *initable,
                                              gpointer user_data)
 {
 	GTask *task;
+	InitBaseClosure *base;
 
-	task = g_task_new (initable, cancellable, callback, user_data);
+	task = g_task_new (initable, cancellable, NULL, NULL);
 	g_task_set_source_tag (task, secret_collection_async_initable_init_async);
 
+	base = g_new0 (InitBaseClosure, 1);
+	base->callback = callback;
+	base->user_data = user_data;
+	g_task_set_task_data (task, base, g_free);
+
 	secret_collection_async_initable_parent_iface->init_async (initable,
 	                                                           io_priority,
 	                                                           cancellable,

libsecret/secret-item.c

@@ -512,17 +512,35 @@ on_init_service (GObject *source,
 	g_clear_object (&task);
 }
 
+typedef struct {
+	GAsyncReadyCallback callback;
+	gpointer user_data;
+} InitBaseClosure;
+
+static void
+secret_item_async_initable_init_async (GAsyncInitable *initable,
+                                       int io_priority,
+                                       GCancellable *cancellable,
+                                       GAsyncReadyCallback callback,
+                                       gpointer user_data);
+
 static void
 on_init_base (GObject *source,
               GAsyncResult *result,
               gpointer user_data)
 {
-	GTask *task = G_TASK (user_data);
+	GTask *base_task = G_TASK (user_data);
-	GCancellable *cancellable = g_task_get_cancellable (task);
+	InitBaseClosure *base = g_task_get_task_data (base_task);
+	GCancellable *cancellable = g_task_get_cancellable (base_task);
+	GTask *task;
 	SecretItem *self = SECRET_ITEM (source);
 	GDBusProxy *proxy = G_DBUS_PROXY (self);
 	GError *error = NULL;
 
+	task = g_task_new (source, cancellable, base->callback, base->user_data);
+	g_task_set_source_tag (task, secret_item_async_initable_init_async);
+	g_clear_object (&base_task);
+
 	if (!secret_item_async_initable_parent_iface->init_finish (G_ASYNC_INITABLE (self),
 	                                                           result, &error)) {
 		g_task_return_error (task, g_steal_pointer (&error));
@@ -552,10 +570,16 @@ secret_item_async_initable_init_async (GAsyncInitable *initable,
                                        gpointer user_data)
 {
 	GTask *task;
+	InitBaseClosure *base;
 
-	task = g_task_new (initable, cancellable, callback, user_data);
+	task = g_task_new (initable, cancellable, NULL, NULL);
 	g_task_set_source_tag (task, secret_item_async_initable_init_async);
 
+	base = g_new0 (InitBaseClosure, 1);
+	base->callback = callback;
+	base->user_data = user_data;
+	g_task_set_task_data (task, base, g_free);
+
 	secret_item_async_initable_parent_iface->init_async (initable, io_priority,
 	                                                     cancellable,
 	                                                     on_init_base,

libsecret/secret-service.c

@@ -717,18 +717,41 @@ secret_service_initable_iface (GInitableIface *iface)
 	iface->init = secret_service_initable_init;
 }
 
+static void
+secret_service_async_initable_init_async (GAsyncInitable *initable,
+                                          int io_priority,
+                                          GCancellable *cancellable,
+                                          GAsyncReadyCallback callback,
+                                          gpointer user_data);
+
+typedef struct {
+	GAsyncReadyCallback callback;
+	gpointer user_data;
+} InitBaseClosure;
+
 static void
 on_init_base (GObject *source,
               GAsyncResult *result,
               gpointer user_data)
 {
-	GTask *task = G_TASK (user_data);
+	GTask *base_task = G_TASK (user_data);
+	InitBaseClosure *base = g_task_get_task_data (base_task);
+	GCancellable *cancellable = g_task_get_cancellable (base_task);
+	GTask *task;
+	InitClosure *init;
 	SecretService *self = SECRET_SERVICE (source);
 	GError *error = NULL;
 
+	task = g_task_new (source, cancellable, base->callback, base->user_data);
+	g_task_set_source_tag (task, secret_service_async_initable_init_async);
+	init = g_slice_new0 (InitClosure);
+	g_task_set_task_data (task, init, init_closure_free);
+
+	g_clear_object (&base_task);
+
 	if (!secret_service_async_initable_parent_iface->init_finish (G_ASYNC_INITABLE (self),
 	                                                              result, &error)) {
-		g_task_return_error (task, error);
+		g_task_return_error (task, g_steal_pointer (&error));
 	} else {
 		service_ensure_for_flags_async (self, self->pv->init_flags, task);
 	}
@@ -744,12 +767,14 @@ secret_service_async_initable_init_async (GAsyncInitable *initable,
                                           gpointer user_data)
 {
 	GTask *task;
-	InitClosure *closure;
+	InitBaseClosure *base;
 
-	task = g_task_new (initable, cancellable, callback, user_data);
+	task = g_task_new (initable, cancellable, NULL, NULL);
 	g_task_set_source_tag (task, secret_service_async_initable_init_async);
-	closure = g_slice_new0 (InitClosure);
+	base = g_new0 (InitBaseClosure, 1);
-	g_task_set_task_data (task, closure, init_closure_free);
+	base->callback = callback;
+	base->user_data = user_data;
+	g_task_set_task_data (task, base, g_free);
 
 	secret_service_async_initable_parent_iface->init_async (initable,
 	                                                        io_priority,