yading@11: /*
yading@11:  * Copyright (c) 2012 Ronald S. Bultje <rsbultje@gmail.com>
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: #ifndef AVUTIL_ATOMIC_H
yading@11: #define AVUTIL_ATOMIC_H
yading@11: 
yading@11: #include "config.h"
yading@11: 
yading@11: #if HAVE_ATOMICS_GCC
yading@11: #include "atomic_gcc.h"
yading@11: #elif HAVE_ATOMICS_WIN32
yading@11: #include "atomic_win32.h"
yading@11: #elif HAVE_ATOMICS_SUNCC
yading@11: #include "atomic_suncc.h"
yading@11: #else
yading@11: 
yading@11: /**
yading@11:  * Load the current value stored in an atomic integer.
yading@11:  *
yading@11:  * @param ptr atomic integer
yading@11:  * @return the current value of the atomic integer
yading@11:  * @note This acts as a memory barrier.
yading@11:  */
yading@11: int avpriv_atomic_int_get(volatile int *ptr);
yading@11: 
yading@11: /**
yading@11:  * Store a new value in an atomic integer.
yading@11:  *
yading@11:  * @param ptr atomic integer
yading@11:  * @param val the value to store in the atomic integer
yading@11:  * @note This acts as a memory barrier.
yading@11:  */
yading@11: void avpriv_atomic_int_set(volatile int *ptr, int val);
yading@11: 
yading@11: /**
yading@11:  * Add a value to an atomic integer.
yading@11:  *
yading@11:  * @param ptr atomic integer
yading@11:  * @param inc the value to add to the atomic integer (may be negative)
yading@11:  * @return the new value of the atomic integer.
yading@11:  * @note This does NOT act as a memory barrier. This is primarily
yading@11:  *       intended for reference counting.
yading@11:  */
yading@11: int avpriv_atomic_int_add_and_fetch(volatile int *ptr, int inc);
yading@11: 
yading@11: /**
yading@11:  * Atomic pointer compare and swap.
yading@11:  *
yading@11:  * @param ptr pointer to the pointer to operate on
yading@11:  * @param oldval do the swap if the current value of *ptr equals to oldval
yading@11:  * @param newval value to replace *ptr with
yading@11:  * @return the value of *ptr before comparison
yading@11:  */
yading@11: void *avpriv_atomic_ptr_cas(void * volatile *ptr, void *oldval, void *newval);
yading@11: 
yading@11: #endif /* HAVE_MEMORYBARRIER */
yading@11: #endif /* AVUTIL_ATOMIC_H */