1 // Low-level functions for atomic operations: Generic version -*- C++ -*-
3 // Copyright (C) 1999, 2001, 2002, 2003, 2004, 2005, 2006, 2009, 2010
4 // Free Software Foundation, Inc.
6 // This file is part of the GNU ISO C++ Library. This library is free
7 // software; you can redistribute it and/or modify it under the
8 // terms of the GNU General Public License as published by the
9 // Free Software Foundation; either version 3, or (at your option)
12 // This library is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
17 // Under Section 7 of GPL version 3, you are granted additional
18 // permissions described in the GCC Runtime Library Exception, version
19 // 3.1, as published by the Free Software Foundation.
21 // You should have received a copy of the GNU General Public License and
22 // a copy of the GCC Runtime Library Exception along with this program;
23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 // <http://www.gnu.org/licenses/>.
26 #include <ext/atomicity.h>
27 #include <ext/concurrence.h>
34 static __gnu_cxx::__mutex atomic_mutex;
37 } // anonymous namespace
39 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
41 _GLIBCXX_BEGIN_NAMESPACE_VERSION
44 __attribute__ ((__unused__))
45 __exchange_and_add(volatile _Atomic_word* __mem, int __val) throw ()
47 __gnu_cxx::__scoped_lock sentry(get_atomic_mutex());
48 _Atomic_word __result;
55 __attribute__ ((__unused__))
56 __atomic_add(volatile _Atomic_word* __mem, int __val) throw ()
57 { __exchange_and_add(__mem, __val); }
59 _GLIBCXX_END_NAMESPACE_VERSION