Atomic.h.svn-base
上传用户:market2
上传日期:2018-11-18
资源大小:18786k
文件大小:2k
- /*
- * OpenKore C++ Standard Library
- * Copyright (C) 2006 VCL
- *
- * This 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.
- *
- * This 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 this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
- * MA 02110-1301 USA
- */
- #ifndef _OSL_ATOMIC_H_
- #define _OSL_ATOMIC_H_
- namespace OSL {
- /**
- * Basic atomic integer operations.
- *
- * This class provides functions for atomically increasing and decreasing
- * integers. On certain platforms, this is implemented as assembly, with
- * fallback implementations on other platforms. Using these functions can
- * sometimes avoid the use of relatively expensive mutexes.
- *
- * @warning
- * Be careful with using these functions, they can cause all kinds of
- * weird problems. Read <a href="http://en.wikipedia.org/wiki/Memory_barrier">the
- * Wikipedia article about memory barriers</a> on why this is so. As such,
- * these functions should only be used for simple reference counting,
- * unless you really know what goes on behind the scenes.
- *
- * @class Atomic OSL/Threading/Atomic.h
- * @ingroup Threading
- * @see OSL::Mutex
- */
- class Atomic {
- public:
- /**
- * Atomically increase an integer by 1.
- */
- static void increment(volatile int &i) throw();
- /**
- * Atomically decrease an integer by 1.
- *
- * @return Whether the integer is 0 after the decrement
- * was performed.
- */
- static bool decrement(volatile int &i) throw();
- };
- }
- #endif /* _OSL_ATOMIC_H_ */