1 #ifndef BABELTRACE_OBJECT_INTERNAL_H
2 #define BABELTRACE_OBJECT_INTERNAL_H
5 * Copyright 2015 Jérémie Galarneau <jeremie.galarneau@efficios.com>
7 * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
9 * Permission is hereby granted, free of charge, to any person obtaining a copy
10 * of this software and associated documentation files (the "Software"), to deal
11 * in the Software without restriction, including without limitation the rights
12 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13 * copies of the Software, and to permit persons to whom the Software is
14 * furnished to do so, subject to the following conditions:
16 * The above copyright notice and this permission notice shall be included in
17 * all copies or substantial portions of the Software.
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
22 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
28 #include <babeltrace/babeltrace-internal.h>
29 #include <babeltrace/assert-internal.h>
34 typedef void (*bt_object_release_func
)(struct bt_object
*);
35 typedef void (*bt_object_parent_is_owner_listener_func
)(
39 void bt_object_get_no_null_check(const void *obj
);
42 void bt_object_put_no_null_check(const void *obj
);
45 * Babeltrace object base.
47 * All objects publicly exposed by Babeltrace APIs must contain this
48 * object as their first member.
52 * True if this object is shared, that is, it has a reference
58 * Current reference count.
60 unsigned long long ref_count
;
63 * Release function called when the object's reference count
64 * falls to zero. For an object with a parent, this function is
65 * bt_object_with_parent_release_func(), which calls
66 * `spec_release_func` below if there's no current parent.
68 bt_object_release_func release_func
;
71 * Specific release function called by
72 * bt_object_with_parent_release_func() or directly by a
75 bt_object_release_func spec_release_func
;
78 * Optional callback for an object with a parent, called by
79 * bt_object_with_parent_release_func() to indicate to the
80 * object that its parent is its owner.
82 bt_object_parent_is_owner_listener_func
83 parent_is_owner_listener_func
;
86 * Optional parent object.
88 struct bt_object
*parent
;
92 unsigned long long bt_object_get_ref_count(const struct bt_object
*c_obj
)
94 struct bt_object
*obj
= (void *) c_obj
;
97 BT_ASSERT(obj
->is_shared
);
98 return obj
->ref_count
;
102 struct bt_object
*bt_object_borrow_parent(const struct bt_object
*c_obj
)
104 struct bt_object
*obj
= (void *) c_obj
;
107 BT_ASSERT(obj
->is_shared
);
112 struct bt_object
*bt_object_get_parent(const struct bt_object
*c_obj
)
114 struct bt_object
*obj
= (void *) c_obj
;
115 struct bt_object
*parent
= bt_object_borrow_parent(obj
);
118 bt_object_get_no_null_check(parent
);
125 void bt_object_set_parent(struct bt_object
*child
, struct bt_object
*parent
)
128 BT_ASSERT(child
->is_shared
);
131 BT_LOGV("Setting object's parent: addr=%p, parent-addr=%p",
136 * It is assumed that a "child" having a parent is publicly
137 * reachable. Therefore, a reference to its parent must be
138 * taken. The reference to the parent will be released once the
139 * object's reference count falls to zero.
142 BT_ASSERT(!child
->parent
);
143 child
->parent
= parent
;
144 bt_object_get_no_null_check(parent
);
147 bt_object_put_no_null_check(child
->parent
);
150 child
->parent
= NULL
;
155 void bt_object_try_spec_release(struct bt_object
*obj
)
158 BT_ASSERT(obj
->is_shared
);
159 BT_ASSERT(obj
->spec_release_func
);
161 if (bt_object_get_ref_count(obj
) == 0) {
162 obj
->spec_release_func(obj
);
167 void bt_object_with_parent_release_func(struct bt_object
*obj
)
171 * Keep our own copy of the parent address because `obj`
172 * could be destroyed in
173 * obj->parent_is_owner_listener_func().
175 struct bt_object
*parent
= obj
->parent
;
178 BT_LOGV("Releasing parented object: addr=%p, ref-count=%llu, "
179 "parent-addr=%p, parent-ref-count=%llu",
181 parent
, parent
->ref_count
);
184 if (obj
->parent_is_owner_listener_func
) {
186 * Object has a chance to destroy itself here
187 * under certain conditions and notify its
188 * parent. At this point the parent is
189 * guaranteed to exist because it's not put yet.
191 obj
->parent_is_owner_listener_func(obj
);
194 /* The release function will be invoked by the parent. */
195 bt_object_put_no_null_check(parent
);
197 bt_object_try_spec_release(obj
);
202 void bt_object_init(struct bt_object
*obj
, bool is_shared
,
203 bt_object_release_func release_func
)
206 BT_ASSERT(!is_shared
|| release_func
);
207 obj
->is_shared
= is_shared
;
208 obj
->release_func
= release_func
;
209 obj
->parent_is_owner_listener_func
= NULL
;
210 obj
->spec_release_func
= NULL
;
216 void bt_object_init_shared(struct bt_object
*obj
,
217 bt_object_release_func release_func
)
219 bt_object_init(obj
, true, release_func
);
223 void bt_object_init_unique(struct bt_object
*obj
)
225 bt_object_init(obj
, false, NULL
);
229 void bt_object_init_shared_with_parent(struct bt_object
*obj
,
230 bt_object_release_func spec_release_func
)
233 BT_ASSERT(spec_release_func
);
234 bt_object_init_shared(obj
, bt_object_with_parent_release_func
);
235 obj
->spec_release_func
= spec_release_func
;
239 void bt_object_set_parent_is_owner_listener_func(struct bt_object
*obj
,
240 bt_object_parent_is_owner_listener_func func
)
243 BT_ASSERT(obj
->is_shared
);
244 BT_ASSERT(obj
->spec_release_func
);
245 ((struct bt_object
*) obj
)->parent_is_owner_listener_func
= func
;
249 void bt_object_inc_ref_count(const struct bt_object
*c_obj
)
251 struct bt_object
*obj
= (void *) c_obj
;
254 BT_ASSERT(obj
->is_shared
);
256 BT_ASSERT(obj
->ref_count
!= 0);
260 void bt_object_get_no_null_check_no_parent_check(const struct bt_object
*c_obj
)
262 struct bt_object
*obj
= (void *) c_obj
;
265 BT_ASSERT(obj
->is_shared
);
268 BT_LOGV("Incrementing object's reference count: %llu -> %llu: "
269 "addr=%p, cur-count=%llu, new-count=%llu",
270 obj
->ref_count
, obj
->ref_count
+ 1,
271 obj
, obj
->ref_count
, obj
->ref_count
+ 1);
274 bt_object_inc_ref_count(obj
);
278 void bt_object_get_no_null_check(const void *c_obj
)
280 struct bt_object
*obj
= (void *) c_obj
;
283 BT_ASSERT(obj
->is_shared
);
285 if (unlikely(obj
->parent
&& bt_object_get_ref_count(obj
) == 0)) {
287 BT_LOGV("Incrementing object's parent's reference count: "
288 "addr=%p, parent-addr=%p", obj
, obj
->parent
);
291 bt_object_get_no_null_check(obj
->parent
);
295 BT_LOGV("Incrementing object's reference count: %llu -> %llu: "
296 "addr=%p, cur-count=%llu, new-count=%llu",
297 obj
->ref_count
, obj
->ref_count
+ 1,
298 obj
, obj
->ref_count
, obj
->ref_count
+ 1);
301 bt_object_inc_ref_count(obj
);
305 void bt_object_put_no_null_check(const void *c_obj
)
307 struct bt_object
*obj
= (void *) c_obj
;
310 BT_ASSERT(obj
->is_shared
);
311 BT_ASSERT(obj
->ref_count
> 0);
314 BT_LOGV("Decrementing object's reference count: %llu -> %llu: "
315 "addr=%p, cur-count=%llu, new-count=%llu",
316 obj
->ref_count
, obj
->ref_count
- 1,
317 obj
, obj
->ref_count
, obj
->ref_count
- 1);
322 if (obj
->ref_count
== 0) {
323 BT_ASSERT(obj
->release_func
);
324 obj
->release_func(obj
);
328 #endif /* BABELTRACE_OBJECT_INTERNAL_H */