lib/ref.c

   1 /*
   2  * ref.c: reference counting
   3  *
   4  * Babeltrace Library
   5  *
   6  * Copyright (c) 2015 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a copy
   9  * of this software and associated documentation files (the "Software"), to deal
  10  * in the Software without restriction, including without limitation the rights
  11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12  * copies of the Software, and to permit persons to whom the Software is
  13  * furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  21  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  24  * SOFTWARE.
  25  */
  26
  27 #define BT_LOG_TAG "REF"
  28 #include <babeltrace/lib-logging-internal.h>
  29
  30 #include <babeltrace/ref-internal.h>
  31 #include <babeltrace/object-internal.h>
  32
  33 void *bt_get(void *ptr)
  34 {
  35         struct bt_object *obj = ptr;
  36
  37         if (unlikely(!obj)) {
  38                 goto end;
  39         }
  40
  41         if (unlikely(!obj->ref_count.release)) {
  42                 goto end;
  43         }
  44
  45         if (unlikely(obj->parent && bt_object_get_ref_count(obj) == 0)) {
  46                 BT_LOGV("Incrementing object's parent's reference count: "
  47                         "addr=%p, parent-addr=%p", ptr, obj->parent);
  48                 bt_get(obj->parent);
  49         }
  50         BT_LOGV("Incrementing object's reference count: %lu -> %lu: "
  51                 "addr=%p, cur-count=%lu, new-count=%lu",
  52                 obj->ref_count.count, obj->ref_count.count + 1,
  53                 ptr,
  54                 obj->ref_count.count, obj->ref_count.count + 1);
  55         bt_ref_get(&obj->ref_count);
  56
  57 end:
  58         return obj;
  59 }
  60
  61 void bt_put(void *ptr)
  62 {
  63         struct bt_object *obj = ptr;
  64
  65         if (unlikely(!obj)) {
  66                 return;
  67         }
  68
  69         if (unlikely(!obj->ref_count.release)) {
  70                 return;
  71         }
  72
  73         if (BT_LOG_ON_WARN && unlikely(bt_object_get_ref_count(obj) == 0)) {
  74                 BT_LOGW("Decrementing a reference count set to 0: addr=%p",
  75                         ptr);
  76         }
  77
  78         BT_LOGV("Decrementing object's reference count: %lu -> %lu: "
  79                 "addr=%p, cur-count=%lu, new-count=%lu",
  80                 obj->ref_count.count, obj->ref_count.count - 1,
  81                 ptr,
  82                 obj->ref_count.count, obj->ref_count.count - 1);
  83         bt_ref_put(&obj->ref_count);
  84 }