1 #ifndef BABELTRACE_OBJECT_INTERNAL_H
2 #define BABELTRACE_OBJECT_INTERNAL_H
5 * Babeltrace - Base object
7 * Copyright 2015 Jérémie Galarneau <jeremie.galarneau@efficios.com>
9 * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
11 * Permission is hereby granted, free of charge, to any person obtaining a copy
12 * of this software and associated documentation files (the "Software"), to deal
13 * in the Software without restriction, including without limitation the rights
14 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
15 * copies of the Software, and to permit persons to whom the Software is
16 * furnished to do so, subject to the following conditions:
18 * The above copyright notice and this permission notice shall be included in
19 * all copies or substantial portions of the Software.
21 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
22 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
23 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
24 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
25 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
26 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 #include <babeltrace/babeltrace-internal.h>
31 #include <babeltrace/ref-internal.h>
32 #include <babeltrace/ref.h>
33 #include <babeltrace/assert-internal.h>
37 * All objects publicly exposed by Babeltrace APIs must contain this structure
38 * as their first member. This allows the unification of all ref counting
39 * mechanisms and may be used to provide more base functionality to all
43 struct bt_ref ref_count
;
44 /* Class-specific, optional release function. */
45 bt_object_release_func release
;
46 /* Class-specific, optional "parent is owner" notification listener. */
47 bt_object_release_func parent_is_owner_listener
;
48 /* @see doc/ref-counting.md */
49 struct bt_object
*parent
;
52 * True if this object is shared, that is, it uses reference
53 * counting. Only used in developer mode.
59 long bt_object_get_ref_count(const void *ptr
)
61 const struct bt_object
*obj
= ptr
;
63 return obj
->ref_count
.count
;
67 void bt_object_release(void *ptr
)
69 struct bt_object
*obj
= ptr
;
72 BT_LOGV("Releasing object: addr=%p, ref-count=%lu", ptr
,
73 obj
->ref_count
.count
);
76 if (obj
&& obj
->release
&& bt_object_get_ref_count(obj
) == 0) {
82 void generic_release(struct bt_object
*obj
)
85 struct bt_object
*parent
= obj
->parent
;
88 BT_LOGV("Releasing parented object: addr=%p, ref-count=%lu, "
89 "parent-addr=%p, parent-ref-count=%lu",
90 obj
, obj
->ref_count
.count
,
91 parent
, parent
->ref_count
.count
);
94 if (obj
->parent_is_owner_listener
) {
96 * Object has a chance to destroy itself here
97 * under certain conditions and notify its
98 * parent. At this point the parent is
99 * guaranteed to exist because it's not put yet.
101 obj
->parent_is_owner_listener(obj
);
104 /* The release function will be invoked by the parent. */
107 bt_object_release(obj
);
112 struct bt_object
*bt_object_borrow_parent(void *ptr
)
114 struct bt_object
*obj
= ptr
;
116 return obj
? obj
->parent
: NULL
;
120 struct bt_object
*bt_object_get_parent(void *ptr
)
122 return bt_get(bt_object_borrow_parent(ptr
));
126 void bt_object_set_parent(void *child_ptr
, void *parent
)
128 struct bt_object
*child
= child_ptr
;
135 BT_LOGV("Setting object's parent: addr=%p, parent-addr=%p",
140 * It is assumed that a "child" being "parented" is publicly reachable.
141 * Therefore, a reference to its parent must be taken. The reference
142 * to the parent will be released once the object's reference count
145 BT_PUT(child
->parent
);
146 child
->parent
= bt_get(parent
);
151 void _bt_object_set_is_shared(struct bt_object
*obj
, bool is_shared
)
153 obj
->is_shared
= is_shared
;
156 # define bt_object_set_is_shared _bt_object_set_is_shared
158 # define bt_object_set_is_shared(_obj, _is_shared)
162 void bt_object_init(void *ptr
, bt_object_release_func release
)
164 struct bt_object
*obj
= ptr
;
166 obj
->release
= release
;
168 bt_object_set_is_shared(obj
, true);
169 bt_ref_init(&obj
->ref_count
, generic_release
);
173 void bt_object_set_parent_is_owner_listener(void *obj
,
174 bt_object_release_func cb
)
177 ((struct bt_object
*) obj
)->parent_is_owner_listener
= cb
;
180 #endif /* BABELTRACE_OBJECT_INTERNAL_H */