1 /**************************************************************************/
2 /* ---------------------------------------------------------------------- */
3 /* Copyright (C) 2006 - 2008 FRESCOR consortium partners: */
5 /* Universidad de Cantabria, SPAIN */
6 /* University of York, UK */
7 /* Scuola Superiore Sant'Anna, ITALY */
8 /* Kaiserslautern University, GERMANY */
9 /* Univ. Politécnica Valencia, SPAIN */
10 /* Czech Technical University in Prague, CZECH REPUBLIC */
12 /* Thales Communication S.A. FRANCE */
13 /* Visual Tools S.A. SPAIN */
14 /* Rapita Systems Ltd UK */
17 /* See http://www.frescor.org for a link to partners' websites */
19 /* FRESCOR project (FP6/2005/IST/5-034026) is funded */
20 /* in part by the European Union Sixth Framework Programme */
21 /* The European Union is not liable of any use that may be */
22 /* made of this code. */
25 /* This file is part of FORB (Frescor Object Request Broker) */
27 /* FORB is free software; you can redistribute it and/or modify it */
28 /* under terms of the GNU General Public License as published by the */
29 /* Free Software Foundation; either version 2, or (at your option) any */
30 /* later version. FORB is distributed in the hope that it will be */
31 /* useful, but WITHOUT ANY WARRANTY; without even the implied warranty */
32 /* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU */
33 /* General Public License for more details. You should have received a */
34 /* copy of the GNU General Public License along with FORB; see file */
35 /* COPYING. If not, write to the Free Software Foundation, 675 Mass Ave, */
36 /* Cambridge, MA 02139, USA. */
38 /* As a special exception, including FORB header files in a file, */
39 /* instantiating FORB generics or templates, or linking other files */
40 /* with FORB objects to produce an executable application, does not */
41 /* by itself cause the resulting executable application to be covered */
42 /* by the GNU General Public License. This exception does not */
43 /* however invalidate any other reasons why the executable file might be */
44 /* covered by the GNU Public License. */
45 /**************************************************************************/
49 * @author Michal Sojka <sojkam1@fel.cvut.cz>
50 * @date Wed Oct 1 09:23:40 2008
52 * @brief Atomic reference counting operations.
54 * @note To provide portable atomicity, we use GCC's builtin
55 * functions introduced in GCC 4.1.
60 void forb_ref_set(struct forb_ref *ref, int num)
66 * Initializes reference count to 1.
70 void forb_ref_init(struct forb_ref *ref)
76 * Atomicaly increases reference count
80 void forb_ref_get(struct forb_ref *ref)
82 __sync_add_and_fetch(&ref->refcount, 1);
86 * Atomicaly decreases reference count and if zero is reached calls, @a
87 * release function (destructor).
89 * @param ref Reference to act on.
90 * @param release Release function called when reference count reaches zero.
92 * @return 1 if the @a release function was called, zero othewise
93 * (which doesn't mean that the object still exist in memory as it
94 * might be released by somebody else in the mean time).
96 int forb_ref_put(struct forb_ref *ref, void (*release) (struct forb_ref *ref))
98 if (__sync_add_and_fetch(&ref->refcount, -1) == 0) {