qom: add child properties (composition) (v3) (3de1c3e8) · Commits · SUMMER2020 / students / proj-2021291

hw/qdev.c

+26 −0

Original line number	Diff line number	Diff line
		@@ -1174,6 +1174,32 @@ DeviceState *qdev_get_root(void)
		return qdev_root;
		}

		static void qdev_get_child_property(DeviceState dev, Visitor v, void *opaque,
		const char name, Error *errp)
		{
		DeviceState *child = opaque;
		gchar *path;

		path = qdev_get_canonical_path(child);
		visit_type_str(v, &path, name, errp);
		g_free(path);
		}

		void qdev_property_add_child(DeviceState dev, const char name,
		DeviceState child, Error *errp)
		{
		gchar *type;

		type = g_strdup_printf("child<%s>", child->info->name);

		qdev_property_add(dev, name, type, qdev_get_child_property,
		NULL, NULL, child, errp);

		qdev_ref(child);

		g_free(type);
		}

		static gchar qdev_get_path_in(DeviceState parent, DeviceState *dev)
		{
		DeviceProperty *prop;

+20 −0

Original line number	Diff line number	Diff line
		@@ -527,4 +527,24 @@ gchar qdev_get_canonical_path(DeviceState dev);
		*/
		DeviceState qdev_resolve_path(const char path, bool *ambiguous);

		/**
		* @qdev_property_add_child - Add a child property to a device
		*
		* Child properties form the composition tree. All devices need to be a child
		* of another device. Devices can only be a child of one device.
		*
		* There is no way for a child to determine what its parent is. It is not
		* a bidirectional relationship. This is by design.
		*
		* @dev - the device to add a property to
		*
		* @name - the name of the property
		*
		* @child - the child device
		*
		* @errp - if an error occurs, a pointer to an area to store the area
		*/
		void qdev_property_add_child(DeviceState dev, const char name,
		DeviceState child, Error *errp);

		#endif