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- /* 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, write to the Free
- Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
- 02111-1307 USA. */
- #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 */
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