| /* |
| * 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. |
| */ |
| |
| #ifndef Threading_h |
| #define Threading_h |
| |
| #include "wtf/Atomics.h" |
| #include "wtf/TypeTraits.h" |
| #include "wtf/WTFExport.h" |
| #include <stdint.h> |
| |
| // For portability, we do not make use of C++11 thread-safe statics, as |
| // supported by some toolchains. Make use of double-checked locking to reduce |
| // overhead. Note that this uses system-wide default lock, and cannot be used |
| // before WTF::initializeThreading() is called. |
| #define DEFINE_THREAD_SAFE_STATIC_LOCAL(T, name, initializer) \ |
| /* Init to nullptr is thread-safe on all implementations. */ \ |
| static void* name##Pointer = nullptr; \ |
| if (!WTF::acquireLoad(&name##Pointer)) { \ |
| WTF::lockAtomicallyInitializedStaticMutex(); \ |
| if (!WTF::acquireLoad(&name##Pointer)) { \ |
| std::remove_const<T>::type* initializerResult = initializer; \ |
| WTF::releaseStore(&name##Pointer, initializerResult); \ |
| } \ |
| WTF::unlockAtomicallyInitializedStaticMutex(); \ |
| } \ |
| T& name = *static_cast<T*>(name##Pointer) |
| |
| namespace WTF { |
| |
| #if OS(WIN) |
| typedef uint32_t ThreadIdentifier; |
| #else |
| typedef intptr_t ThreadIdentifier; |
| #endif |
| |
| WTF_EXPORT ThreadIdentifier currentThread(); |
| |
| WTF_EXPORT void lockAtomicallyInitializedStaticMutex(); |
| WTF_EXPORT void unlockAtomicallyInitializedStaticMutex(); |
| |
| #if ENABLE(ASSERT) |
| WTF_EXPORT bool isAtomicallyInitializedStaticMutexLockHeld(); |
| WTF_EXPORT bool isBeforeThreadCreated(); |
| WTF_EXPORT void willCreateThread(); |
| #endif |
| |
| } // namespace WTF |
| |
| using WTF::ThreadIdentifier; |
| using WTF::currentThread; |
| |
| #endif // Threading_h |