+++ /dev/null
-/*
- * Copyright (C) 2007, 2008, 2010 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.
- * 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.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE 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
- * 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.
- */
-
-#ifndef ThreadSafeShared_h
-#define ThreadSafeShared_h
-
-#include "Platform.h"
-
-#include <wtf/Atomics.h>
-#include <wtf/Noncopyable.h>
-#include <wtf/ThreadingPrimitives.h>
-
-namespace WTF {
-
-class ThreadSafeSharedBase : public Noncopyable {
-public:
- ThreadSafeSharedBase(int initialRefCount = 1)
- : m_refCount(initialRefCount)
- {
- }
-
- void ref()
- {
-#if USE(LOCKFREE_THREADSAFESHARED)
- atomicIncrement(&m_refCount);
-#else
- MutexLocker locker(m_mutex);
- ++m_refCount;
-#endif
- }
-
- bool hasOneRef()
- {
- return refCount() == 1;
- }
-
- int refCount() const
- {
-#if !USE(LOCKFREE_THREADSAFESHARED)
- MutexLocker locker(m_mutex);
-#endif
- return static_cast<int const volatile &>(m_refCount);
- }
-
-protected:
- // Returns whether the pointer should be freed or not.
- bool derefBase()
- {
-#if USE(LOCKFREE_THREADSAFESHARED)
- if (atomicDecrement(&m_refCount) <= 0)
- return true;
-#else
- int refCount;
- {
- MutexLocker locker(m_mutex);
- --m_refCount;
- refCount = m_refCount;
- }
- if (refCount <= 0)
- return true;
-#endif
- return false;
- }
-
-private:
- template<class T>
- friend class CrossThreadRefCounted;
-
- int m_refCount;
-#if !USE(LOCKFREE_THREADSAFESHARED)
- mutable Mutex m_mutex;
-#endif
-};
-
-template<class T> class ThreadSafeShared : public ThreadSafeSharedBase {
-public:
- ThreadSafeShared(int initialRefCount = 1)
- : ThreadSafeSharedBase(initialRefCount)
- {
- }
-
- void deref()
- {
- if (derefBase())
- delete static_cast<T*>(this);
- }
-};
-
-} // namespace WTF
-
-using WTF::ThreadSafeShared;
-
-#endif // ThreadSafeShared_h
projects / apple / javascriptcore.git / blobdiff