/* * Copyright (c) 2012 Ronald S. Bultje <rsbultje@gmail.com> * * This file is part of FFmpeg. * * FFmpeg 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. * * FFmpeg 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 FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef AVUTIL_ATOMIC_H #define AVUTIL_ATOMIC_H #include "config.h" #if HAVE_ATOMICS_NATIVE #if HAVE_ATOMICS_GCC #include "atomic_gcc.h" #elif HAVE_ATOMICS_WIN32 #include "atomic_win32.h" #elif HAVE_ATOMICS_SUNCC #include "atomic_suncc.h" #endif #else /** * Load the current value stored in an atomic integer. * * @param ptr atomic integer * @return the current value of the atomic integer * @note This acts as a memory barrier. */ int avpriv_atomic_int_get(volatile int *ptr); /** * Store a new value in an atomic integer. * * @param ptr atomic integer * @param val the value to store in the atomic integer * @note This acts as a memory barrier. */ void avpriv_atomic_int_set(volatile int *ptr, int val); /** * Add a value to an atomic integer. * * @param ptr atomic integer * @param inc the value to add to the atomic integer (may be negative) * @return the new value of the atomic integer. * @note This does NOT act as a memory barrier. This is primarily * intended for reference counting. */ int avpriv_atomic_int_add_and_fetch(volatile int *ptr, int inc); /** * Atomic pointer compare and swap. * * @param ptr pointer to the pointer to operate on * @param oldval do the swap if the current value of *ptr equals to oldval * @param newval value to replace *ptr with * @return the value of *ptr before comparison */ void *avpriv_atomic_ptr_cas(void * volatile *ptr, void *oldval, void *newval); #endif /* HAVE_ATOMICS_NATIVE */ #endif /* AVUTIL_ATOMIC_H */