X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=include%2Fbabeltrace%2Fobject-internal.h;h=afb9e6eee3cb0cebe2137273bb1fbc637cd43d71;hb=cdc4693da047ef54d55bf17d803605e4880b734e;hp=afba44790723d212465bb9e423278e3ffb647970;hpb=83509119a945fc77faff869daaf48627e1c4b3fa;p=babeltrace.git

diff --git a/include/babeltrace/object-internal.h b/include/babeltrace/object-internal.h
index afba4479..afb9e6ee 100644
--- a/include/babeltrace/object-internal.h
+++ b/include/babeltrace/object-internal.h
@@ -27,22 +27,148 @@
  * 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.
+	 */
+	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);
+}
+
+static inline
+void bt_object_set_is_shared(struct bt_object *obj, bool is_shared)
+{
+	obj->is_shared = is_shared;
+}
+
+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 */