| /* Copyright (C) 2003-2014 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 */ |
