/* Copyright (C) 2003 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@redhat.com>, 2003. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ #ifndef _BITS_ATOMIC_H #define _BITS_ATOMIC_H 1 /* We have by default no support for atomic operations. So define them non-atomic. If this is a problem somebody will have to come up with real definitions. */ /* The only basic operation needed is compare and exchange. */ #define atomic_compare_and_exchange_val_acq(mem, newval, oldval) \ ({ __typeof (mem) __gmemp = (mem); \ __typeof (*mem) __gret = *__gmemp; \ __typeof (*mem) __gnewval = (newval); \ \ if (__gret == (oldval)) \ *__gmemp = __gnewval; \ __gret; }) #define atomic_compare_and_exchange_bool_acq(mem, newval, oldval) \ ({ __typeof (mem) __gmemp = (mem); \ __typeof (*mem) __gnewval = (newval); \ \ *__gmemp == (oldval) ? (*__gmemp = __gnewval, 0) : 1; }) #endif /* bits/atomic.h */