* SOFTWARE.
*/
+#include <babeltrace/babeltrace-internal.h>
#include <babeltrace/ref-internal.h>
+#include <babeltrace/ref.h>
+#include <babeltrace/assert-internal.h>
+#include <stdbool.h>
/**
* All objects publicly exposed by Babeltrace APIs must contain this structure
* as their first member. This allows the unification of all ref counting
- * mechanism and may be used to provide more base functionality to all
+ * mechanisms and may be used to provide more base functionality to all
* objects.
*/
struct bt_object {
struct bt_ref ref_count;
+ /* Class-specific, optional release function. */
+ bt_object_release_func release;
+ /* Class-specific, optional "parent is owner" notification listener. */
+ bt_object_release_func parent_is_owner_listener;
+ /* @see doc/ref-counting.md */
+ struct bt_object *parent;
+
+ /*
+ * True if this object is shared, that is, it uses reference
+ * counting. Only used in developer mode.
+ */
+ bool is_shared;
};
static inline
-void bt_object_init(void *obj, bt_object_release_func release)
+long bt_object_get_ref_count(const void *ptr)
+{
+ const struct bt_object *obj = ptr;
+
+ return obj->ref_count.count;
+}
+
+static inline
+void bt_object_release(void *ptr)
+{
+ struct bt_object *obj = ptr;
+
+#ifdef BT_LOGV
+ BT_LOGV("Releasing object: addr=%p, ref-count=%lu", ptr,
+ obj->ref_count.count);
+#endif
+
+ if (obj && obj->release && bt_object_get_ref_count(obj) == 0) {
+ obj->release(obj);
+ }
+}
+
+static inline
+void generic_release(struct bt_object *obj)
+{
+ if (obj->parent) {
+ struct bt_object *parent = obj->parent;
+
+#ifdef BT_LOGV
+ BT_LOGV("Releasing parented object: addr=%p, ref-count=%lu, "
+ "parent-addr=%p, parent-ref-count=%lu",
+ obj, obj->ref_count.count,
+ parent, parent->ref_count.count);
+#endif
+
+ if (obj->parent_is_owner_listener) {
+ /*
+ * Object has a chance to destroy itself here
+ * under certain conditions and notify its
+ * parent. At this point the parent is
+ * guaranteed to exist because it's not put yet.
+ */
+ obj->parent_is_owner_listener(obj);
+ }
+
+ /* The release function will be invoked by the parent. */
+ bt_put(parent);
+ } else {
+ bt_object_release(obj);
+ }
+}
+
+static inline
+struct bt_object *bt_object_borrow_parent(void *ptr)
+{
+ struct bt_object *obj = ptr;
+
+ return obj ? obj->parent : NULL;
+}
+
+static inline
+struct bt_object *bt_object_get_parent(void *ptr)
+{
+ return bt_get(bt_object_borrow_parent(ptr));
+}
+
+static inline
+void bt_object_set_parent(void *child_ptr, void *parent)
+{
+ struct bt_object *child = child_ptr;
+
+ if (!child) {
+ return;
+ }
+
+#ifdef BT_LOGV
+ BT_LOGV("Setting object's parent: addr=%p, parent-addr=%p",
+ child_ptr, parent);
+#endif
+
+ /*
+ * It is assumed that a "child" being "parented" is publicly reachable.
+ * Therefore, a reference to its parent must be taken. The reference
+ * to the parent will be released once the object's reference count
+ * falls to zero.
+ */
+ BT_PUT(child->parent);
+ child->parent = bt_get(parent);
+}
+
+#ifdef BT_DEV_MODE
+static inline
+void _bt_object_set_is_shared(struct bt_object *obj, bool is_shared)
+{
+ obj->is_shared = is_shared;
+}
+
+# define bt_object_set_is_shared _bt_object_set_is_shared
+#else
+# define bt_object_set_is_shared(_obj, _is_shared)
+#endif
+
+static inline
+void bt_object_init(void *ptr, bt_object_release_func release)
+{
+ struct bt_object *obj = ptr;
+
+ obj->release = release;
+ obj->parent = NULL;
+ bt_object_set_is_shared(obj, true);
+ bt_ref_init(&obj->ref_count, generic_release);
+}
+
+static inline
+void bt_object_set_parent_is_owner_listener(void *obj,
+ bt_object_release_func cb)
{
- bt_ref_init(&((struct bt_object *) obj)->ref_count, release);
+ BT_ASSERT(obj);
+ ((struct bt_object *) obj)->parent_is_owner_listener = cb;
}
#endif /* BABELTRACE_OBJECT_INTERNAL_H */