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/*
* Copyright (C) 2007, 2008 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 Threading_h
#define Threading_h
#if PLATFORM(WIN_CE)
#include <windows.h>
#endif
#include <wtf/Assertions.h>
#include <wtf/Locker.h>
#include <wtf/Noncopyable.h>
#if PLATFORM(WIN_OS) && !PLATFORM(WIN_CE)
#include <windows.h>
#elif PLATFORM(DARWIN)
#include <libkern/OSAtomic.h>
#elif COMPILER(GCC)
#if (__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 2))
#include <ext/atomicity.h>
#else
#include <bits/atomicity.h>
#endif
#endif
#if USE(PTHREADS)
#include <pthread.h>
#elif PLATFORM(GTK)
#include <wtf/GOwnPtr.h>
typedef struct _GMutex GMutex;
typedef struct _GCond GCond;
#endif
#if PLATFORM(QT)
#include <qglobal.h>
QT_BEGIN_NAMESPACE
class QMutex;
class QWaitCondition;
QT_END_NAMESPACE
#endif
#include <stdint.h>
// For portability, we do not use thread-safe statics natively supported by some compilers (e.g. gcc).
#define AtomicallyInitializedStatic(T, name) \
WTF::lockAtomicallyInitializedStaticMutex(); \
static T name; \
WTF::unlockAtomicallyInitializedStaticMutex();
namespace WTF {
typedef uint32_t ThreadIdentifier;
typedef void* (*ThreadFunction)(void* argument);
// Returns 0 if thread creation failed
ThreadIdentifier createThread(ThreadFunction, void*, const char* threadName);
ThreadIdentifier createThreadInternal(ThreadFunction, void*, const char* threadName);
ThreadIdentifier currentThread();
bool isMainThread();
int waitForThreadCompletion(ThreadIdentifier, void**);
void detachThread(ThreadIdentifier);
#if USE(PTHREADS)
typedef pthread_mutex_t PlatformMutex;
typedef pthread_cond_t PlatformCondition;
#elif PLATFORM(GTK)
typedef GOwnPtr<GMutex> PlatformMutex;
typedef GOwnPtr<GCond> PlatformCondition;
#elif PLATFORM(QT)
typedef QT_PREPEND_NAMESPACE(QMutex)* PlatformMutex;
typedef QT_PREPEND_NAMESPACE(QWaitCondition)* PlatformCondition;
#elif PLATFORM(WIN_OS)
struct PlatformMutex {
CRITICAL_SECTION m_internalMutex;
size_t m_recursionCount;
};
struct PlatformCondition {
size_t m_timedOut;
size_t m_blocked;
size_t m_waitingForRemoval;
HANDLE m_gate;
HANDLE m_queue;
HANDLE m_mutex;
};
#else
typedef void* PlatformMutex;
typedef void* PlatformCondition;
#endif
class Mutex : Noncopyable {
public:
Mutex();
~Mutex();
void lock();
bool tryLock();
void unlock();
public:
PlatformMutex& impl() { return m_mutex; }
private:
PlatformMutex m_mutex;
};
typedef Locker<Mutex> MutexLocker;
class ThreadCondition : Noncopyable {
public:
ThreadCondition();
~ThreadCondition();
void wait(Mutex& mutex);
// Returns true if the condition was signaled before the timeout, false if the timeout was reached
bool timedWait(Mutex&, double interval);
void signal();
void broadcast();
private:
PlatformCondition m_condition;
};
#if PLATFORM(WIN_OS)
#define WTF_USE_LOCKFREE_THREADSAFESHARED 1
#if COMPILER(MINGW) || COMPILER(MSVC7) || PLATFORM(WIN_CE)
inline void atomicIncrement(int* addend) { InterlockedIncrement(reinterpret_cast<long*>(addend)); }
inline int atomicDecrement(int* addend) { return InterlockedDecrement(reinterpret_cast<long*>(addend)); }
#else
inline void atomicIncrement(int volatile* addend) { InterlockedIncrement(reinterpret_cast<long volatile*>(addend)); }
inline int atomicDecrement(int volatile* addend) { return InterlockedDecrement(reinterpret_cast<long volatile*>(addend)); }
#endif
#elif PLATFORM(DARWIN)
#define WTF_USE_LOCKFREE_THREADSAFESHARED 1
inline void atomicIncrement(int volatile* addend) { OSAtomicIncrement32Barrier(const_cast<int*>(addend)); }
inline int atomicDecrement(int volatile* addend) { return OSAtomicDecrement32Barrier(const_cast<int*>(addend)); }
#elif COMPILER(GCC)
#define WTF_USE_LOCKFREE_THREADSAFESHARED 1
inline void atomicIncrement(int volatile* addend) { __gnu_cxx::__atomic_add(addend, 1); }
inline int atomicDecrement(int volatile* addend) { return __gnu_cxx::__exchange_and_add(addend, -1) - 1; }
#endif
template<class T> class ThreadSafeShared : Noncopyable {
public:
ThreadSafeShared(int initialRefCount = 1)
: m_refCount(initialRefCount)
{
}
void ref()
{
#if USE(LOCKFREE_THREADSAFESHARED)
atomicIncrement(&m_refCount);
#else
MutexLocker locker(m_mutex);
++m_refCount;
#endif
}
void deref()
{
#if USE(LOCKFREE_THREADSAFESHARED)
if (atomicDecrement(&m_refCount) <= 0)
#else
{
MutexLocker locker(m_mutex);
--m_refCount;
}
if (m_refCount <= 0)
#endif
delete static_cast<T*>(this);
}
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);
}
private:
int m_refCount;
#if !USE(LOCKFREE_THREADSAFESHARED)
mutable Mutex m_mutex;
#endif
};
// This function must be called from the main thread. It is safe to call it repeatedly.
// Darwin is an exception to this rule: it is OK to call it from any thread, the only requirement is that the calls are not reentrant.
void initializeThreading();
void lockAtomicallyInitializedStaticMutex();
void unlockAtomicallyInitializedStaticMutex();
} // namespace WTF
using WTF::Mutex;
using WTF::MutexLocker;
using WTF::ThreadCondition;
using WTF::ThreadIdentifier;
using WTF::ThreadSafeShared;
using WTF::createThread;
using WTF::currentThread;
using WTF::isMainThread;
using WTF::detachThread;
using WTF::waitForThreadCompletion;
#endif // Threading_h
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