diff options
Diffstat (limited to 'Source/WTF/wtf/ThreadSafeRefCounted.h')
| -rw-r--r-- | Source/WTF/wtf/ThreadSafeRefCounted.h | 88 |
1 files changed, 20 insertions, 68 deletions
diff --git a/Source/WTF/wtf/ThreadSafeRefCounted.h b/Source/WTF/wtf/ThreadSafeRefCounted.h index cf9eb3db3..892a058a9 100644 --- a/Source/WTF/wtf/ThreadSafeRefCounted.h +++ b/Source/WTF/wtf/ThreadSafeRefCounted.h @@ -1,66 +1,31 @@ /* - * Copyright (C) 2007, 2008, 2010 Apple Inc. All rights reserved. + * Copyright (C) 2007, 2008, 2010, 2013, 2014 Apple Inc. All rights reserved. * Copyright (C) 2007 Justin Haygood (jhaygood@reaktix.com) * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: - * * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. + * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of - * its contributors may be used to endorse or promote products derived - * from this software without specific prior written permission. + * documentation and/or other materials provided with the distribution. * - * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY + * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE - * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY + * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; - * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND - * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF - * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - * - * - * Note: The implementations of InterlockedIncrement and InterlockedDecrement are based - * on atomic_increment and atomic_exchange_and_add from the Boost C++ Library. The license - * is virtually identical to the Apple license above but is included here for completeness. - * - * Boost Software License - Version 1.0 - August 17th, 2003 - * - * Permission is hereby granted, free of charge, to any person or organization - * obtaining a copy of the software and accompanying documentation covered by - * this license (the "Software") to use, reproduce, display, distribute, - * execute, and transmit the Software, and to prepare derivative works of the - * Software, and to permit third-parties to whom the Software is furnished to - * do so, all subject to the following: - * - * The copyright notices in the Software and this entire statement, including - * the above license grant, this restriction and the following disclaimer, - * must be included in all copies of the Software, in whole or in part, and - * all derivative works of the Software, unless such copies or derivative - * works are solely in the form of machine-executable object code generated by - * a source language processor. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT - * SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE - * FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE, - * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER - * DEALINGS IN THE SOFTWARE. + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ -#ifndef ThreadSafeRefCounted_h -#define ThreadSafeRefCounted_h +#pragma once #include <atomic> -#include <wtf/DynamicAnnotations.h> #include <wtf/FastMalloc.h> #include <wtf/Noncopyable.h> @@ -70,59 +35,46 @@ class ThreadSafeRefCountedBase { WTF_MAKE_NONCOPYABLE(ThreadSafeRefCountedBase); WTF_MAKE_FAST_ALLOCATED; public: - ThreadSafeRefCountedBase(int initialRefCount = 1) - : m_refCount(initialRefCount) - { - } + ThreadSafeRefCountedBase() = default; - void ref() + void ref() const { ++m_refCount; } - bool hasOneRef() + bool hasOneRef() const { return refCount() == 1; } - int refCount() const + unsigned refCount() const { return m_refCount; } protected: // Returns whether the pointer should be freed or not. - bool derefBase() + bool derefBase() const { - WTF_ANNOTATE_HAPPENS_BEFORE(&m_refCount); - if (--m_refCount <= 0) { - WTF_ANNOTATE_HAPPENS_AFTER(&m_refCount); - return true; - } - - return false; + return !--m_refCount; } private: - std::atomic<int> m_refCount; + mutable std::atomic<unsigned> m_refCount { 1 }; }; template<class T> class ThreadSafeRefCounted : public ThreadSafeRefCountedBase { public: - void deref() + void deref() const { if (derefBase()) - delete static_cast<T*>(this); + delete static_cast<const T*>(this); } protected: - ThreadSafeRefCounted() - { - } + ThreadSafeRefCounted() = default; }; } // namespace WTF using WTF::ThreadSafeRefCounted; - -#endif // ThreadSafeRefCounted_h |