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diff --git a/Source/JavaScriptCore/wtf/ThreadingWin.cpp b/Source/JavaScriptCore/wtf/ThreadingWin.cpp
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+/*
+ * Copyright (C) 2007, 2008 Apple Inc. All rights reserved.
+ * Copyright (C) 2009 Google Inc. All rights reserved.
+ * Copyright (C) 2009 Torch Mobile, Inc. All rights reserved.
+ *
+ * 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.
+ */
+
+/*
+ * There are numerous academic and practical works on how to implement pthread_cond_wait/pthread_cond_signal/pthread_cond_broadcast
+ * functions on Win32. Here is one example: http://www.cs.wustl.edu/~schmidt/win32-cv-1.html which is widely credited as a 'starting point'
+ * of modern attempts. There are several more or less proven implementations, one in Boost C++ library (http://www.boost.org) and another
+ * in pthreads-win32 (http://sourceware.org/pthreads-win32/).
+ *
+ * The number of articles and discussions is the evidence of significant difficulties in implementing these primitives correctly.
+ * The brief search of revisions, ChangeLog entries, discussions in comp.programming.threads and other places clearly documents
+ * numerous pitfalls and performance problems the authors had to overcome to arrive to the suitable implementations.
+ * Optimally, WebKit would use one of those supported/tested libraries directly. To roll out our own implementation is impractical,
+ * if even for the lack of sufficient testing. However, a faithful reproduction of the code from one of the popular supported
+ * libraries seems to be a good compromise.
+ *
+ * The early Boost implementation (http://www.boxbackup.org/trac/browser/box/nick/win/lib/win32/boost_1_32_0/libs/thread/src/condition.cpp?rev=30)
+ * is identical to pthreads-win32 (http://sourceware.org/cgi-bin/cvsweb.cgi/pthreads/pthread_cond_wait.c?rev=1.10&content-type=text/x-cvsweb-markup&cvsroot=pthreads-win32).
+ * Current Boost uses yet another (although seemingly equivalent) algorithm which came from their 'thread rewrite' effort.
+ *
+ * This file includes timedWait/signal/broadcast implementations translated to WebKit coding style from the latest algorithm by
+ * Alexander Terekhov and Louis Thomas, as captured here: http://sourceware.org/cgi-bin/cvsweb.cgi/pthreads/pthread_cond_wait.c?rev=1.10&content-type=text/x-cvsweb-markup&cvsroot=pthreads-win32
+ * It replaces the implementation of their previous algorithm, also documented in the same source above.
+ * The naming and comments are left very close to original to enable easy cross-check.
+ *
+ * The corresponding Pthreads-win32 License is included below, and CONTRIBUTORS file which it refers to is added to
+ * source directory (as CONTRIBUTORS.pthreads-win32).
+ */
+
+/*
+ *      Pthreads-win32 - POSIX Threads Library for Win32
+ *      Copyright(C) 1998 John E. Bossom
+ *      Copyright(C) 1999,2005 Pthreads-win32 contributors
+ *
+ *      Contact Email: rpj@callisto.canberra.edu.au
+ *
+ *      The current list of contributors is contained
+ *      in the file CONTRIBUTORS included with the source
+ *      code distribution. The list can also be seen at the
+ *      following World Wide Web location:
+ *      http://sources.redhat.com/pthreads-win32/contributors.html
+ *
+ *      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 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 in the file COPYING.LIB;
+ *      if not, write to the Free Software Foundation, Inc.,
+ *      59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+
+#include "config.h"
+#include "Threading.h"
+
+#include "MainThread.h"
+#include "ThreadFunctionInvocation.h"
+#include <windows.h>
+#include <wtf/CurrentTime.h>
+#include <wtf/HashMap.h>
+#include <wtf/MathExtras.h>
+#include <wtf/OwnPtr.h>
+#include <wtf/PassOwnPtr.h>
+#include <wtf/RandomNumberSeed.h>
+
+#if !USE(PTHREADS) && OS(WINDOWS)
+#include "ThreadSpecific.h"
+#endif
+
+#if !OS(WINCE)
+#include <process.h>
+#endif
+
+#if HAVE(ERRNO_H)
+#include <errno.h>
+#endif
+
+namespace WTF {
+
+// MS_VC_EXCEPTION, THREADNAME_INFO, and setThreadNameInternal all come from <http://msdn.microsoft.com/en-us/library/xcb2z8hs.aspx>.
+static const DWORD MS_VC_EXCEPTION = 0x406D1388;
+
+#pragma pack(push, 8)
+typedef struct tagTHREADNAME_INFO {
+    DWORD dwType; // must be 0x1000
+    LPCSTR szName; // pointer to name (in user addr space)
+    DWORD dwThreadID; // thread ID (-1=caller thread)
+    DWORD dwFlags; // reserved for future use, must be zero
+} THREADNAME_INFO;
+#pragma pack(pop)
+
+void initializeCurrentThreadInternal(const char* szThreadName)
+{
+    THREADNAME_INFO info;
+    info.dwType = 0x1000;
+    info.szName = szThreadName;
+    info.dwThreadID = GetCurrentThreadId();
+    info.dwFlags = 0;
+
+    __try {
+        RaiseException(MS_VC_EXCEPTION, 0, sizeof(info)/sizeof(ULONG_PTR), reinterpret_cast<ULONG_PTR*>(&info));
+    } __except (EXCEPTION_CONTINUE_EXECUTION) {
+    }
+}
+
+static Mutex* atomicallyInitializedStaticMutex;
+
+void lockAtomicallyInitializedStaticMutex()
+{
+    ASSERT(atomicallyInitializedStaticMutex);
+    atomicallyInitializedStaticMutex->lock();
+}
+
+void unlockAtomicallyInitializedStaticMutex()
+{
+    atomicallyInitializedStaticMutex->unlock();
+}
+
+static Mutex& threadMapMutex()
+{
+    static Mutex mutex;
+    return mutex;
+}
+
+void initializeThreading()
+{
+    if (atomicallyInitializedStaticMutex)
+        return;
+
+    atomicallyInitializedStaticMutex = new Mutex;
+    threadMapMutex();
+    initializeRandomNumberGenerator();
+}
+
+static HashMap<DWORD, HANDLE>& threadMap()
+{
+    static HashMap<DWORD, HANDLE> map;
+    return map;
+}
+
+static void storeThreadHandleByIdentifier(DWORD threadID, HANDLE threadHandle)
+{
+    MutexLocker locker(threadMapMutex());
+    ASSERT(!threadMap().contains(threadID));
+    threadMap().add(threadID, threadHandle);
+}
+
+static HANDLE threadHandleForIdentifier(ThreadIdentifier id)
+{
+    MutexLocker locker(threadMapMutex());
+    return threadMap().get(id);
+}
+
+static void clearThreadHandleForIdentifier(ThreadIdentifier id)
+{
+    MutexLocker locker(threadMapMutex());
+    ASSERT(threadMap().contains(id));
+    threadMap().remove(id);
+}
+
+static unsigned __stdcall wtfThreadEntryPoint(void* param)
+{
+    OwnPtr<ThreadFunctionInvocation> invocation = adoptPtr(static_cast<ThreadFunctionInvocation*>(param));
+    void* result = invocation->function(invocation->data);
+
+#if !USE(PTHREADS) && OS(WINDOWS)
+    // Do the TLS cleanup.
+    ThreadSpecificThreadExit();
+#endif
+
+    return reinterpret_cast<unsigned>(result);
+}
+
+ThreadIdentifier createThreadInternal(ThreadFunction entryPoint, void* data, const char* threadName)
+{
+    unsigned threadIdentifier = 0;
+    ThreadIdentifier threadID = 0;
+    OwnPtr<ThreadFunctionInvocation> invocation = adoptPtr(new ThreadFunctionInvocation(entryPoint, data));
+#if OS(WINCE)
+    // This is safe on WINCE, since CRT is in the core and innately multithreaded.
+    // On desktop Windows, need to use _beginthreadex (not available on WinCE) if using any CRT functions
+    HANDLE threadHandle = CreateThread(0, 0, (LPTHREAD_START_ROUTINE)wtfThreadEntryPoint, invocation.get(), 0, (LPDWORD)&threadIdentifier);
+#else
+    HANDLE threadHandle = reinterpret_cast<HANDLE>(_beginthreadex(0, 0, wtfThreadEntryPoint, invocation.get(), 0, &threadIdentifier));
+#endif
+    if (!threadHandle) {
+#if OS(WINCE)
+        LOG_ERROR("Failed to create thread at entry point %p with data %p: %ld", entryPoint, data, ::GetLastError());
+#elif !HAVE(ERRNO_H)
+        LOG_ERROR("Failed to create thread at entry point %p with data %p.", entryPoint, data);
+#else
+        LOG_ERROR("Failed to create thread at entry point %p with data %p: %ld", entryPoint, data, errno);
+#endif
+        return 0;
+    }
+
+    // The thread will take ownership of invocation.
+    invocation.leakPtr();
+
+    threadID = static_cast<ThreadIdentifier>(threadIdentifier);
+    storeThreadHandleByIdentifier(threadIdentifier, threadHandle);
+
+    return threadID;
+}
+
+int waitForThreadCompletion(ThreadIdentifier threadID, void** result)
+{
+    ASSERT(threadID);
+    
+    HANDLE threadHandle = threadHandleForIdentifier(threadID);
+    if (!threadHandle)
+        LOG_ERROR("ThreadIdentifier %u did not correspond to an active thread when trying to quit", threadID);
+ 
+    DWORD joinResult = WaitForSingleObject(threadHandle, INFINITE);
+    if (joinResult == WAIT_FAILED)
+        LOG_ERROR("ThreadIdentifier %u was found to be deadlocked trying to quit", threadID);
+
+    CloseHandle(threadHandle);
+    clearThreadHandleForIdentifier(threadID);
+
+    return joinResult;
+}
+
+void detachThread(ThreadIdentifier threadID)
+{
+    ASSERT(threadID);
+
+    HANDLE threadHandle = threadHandleForIdentifier(threadID);
+    if (threadHandle)
+        CloseHandle(threadHandle);
+    clearThreadHandleForIdentifier(threadID);
+}
+
+void yield()
+{
+    ::Sleep(1);
+}
+
+ThreadIdentifier currentThread()
+{
+    return static_cast<ThreadIdentifier>(GetCurrentThreadId());
+}
+
+Mutex::Mutex()
+{
+    m_mutex.m_recursionCount = 0;
+    InitializeCriticalSection(&m_mutex.m_internalMutex);
+}
+
+Mutex::~Mutex()
+{
+    DeleteCriticalSection(&m_mutex.m_internalMutex);
+}
+
+void Mutex::lock()
+{
+    EnterCriticalSection(&m_mutex.m_internalMutex);
+    ++m_mutex.m_recursionCount;
+}
+    
+bool Mutex::tryLock()
+{
+    // This method is modeled after the behavior of pthread_mutex_trylock,
+    // which will return an error if the lock is already owned by the
+    // current thread.  Since the primitive Win32 'TryEnterCriticalSection'
+    // treats this as a successful case, it changes the behavior of several
+    // tests in WebKit that check to see if the current thread already
+    // owned this mutex (see e.g., IconDatabase::getOrCreateIconRecord)
+    DWORD result = TryEnterCriticalSection(&m_mutex.m_internalMutex);
+    
+    if (result != 0) {       // We got the lock
+        // If this thread already had the lock, we must unlock and
+        // return false so that we mimic the behavior of POSIX's
+        // pthread_mutex_trylock:
+        if (m_mutex.m_recursionCount > 0) {
+            LeaveCriticalSection(&m_mutex.m_internalMutex);
+            return false;
+        }
+
+        ++m_mutex.m_recursionCount;
+        return true;
+    }
+
+    return false;
+}
+
+void Mutex::unlock()
+{
+    --m_mutex.m_recursionCount;
+    LeaveCriticalSection(&m_mutex.m_internalMutex);
+}
+
+bool PlatformCondition::timedWait(PlatformMutex& mutex, DWORD durationMilliseconds)
+{
+    // Enter the wait state.
+    DWORD res = WaitForSingleObject(m_blockLock, INFINITE);
+    ASSERT(res == WAIT_OBJECT_0);
+    ++m_waitersBlocked;
+    res = ReleaseSemaphore(m_blockLock, 1, 0);
+    ASSERT(res);
+
+    LeaveCriticalSection(&mutex.m_internalMutex);
+
+    // Main wait - use timeout.
+    bool timedOut = (WaitForSingleObject(m_blockQueue, durationMilliseconds) == WAIT_TIMEOUT);
+
+    res = WaitForSingleObject(m_unblockLock, INFINITE);
+    ASSERT(res == WAIT_OBJECT_0);
+
+    int signalsLeft = m_waitersToUnblock;
+
+    if (m_waitersToUnblock)
+        --m_waitersToUnblock;
+    else if (++m_waitersGone == (INT_MAX / 2)) { // timeout/canceled or spurious semaphore
+        // timeout or spurious wakeup occured, normalize the m_waitersGone count
+        // this may occur if many calls to wait with a timeout are made and
+        // no call to notify_* is made
+        res = WaitForSingleObject(m_blockLock, INFINITE);
+        ASSERT(res == WAIT_OBJECT_0);
+        m_waitersBlocked -= m_waitersGone;
+        res = ReleaseSemaphore(m_blockLock, 1, 0);
+        ASSERT(res);
+        m_waitersGone = 0;
+    }
+
+    res = ReleaseMutex(m_unblockLock);
+    ASSERT(res);
+
+    if (signalsLeft == 1) {
+        res = ReleaseSemaphore(m_blockLock, 1, 0); // Open the gate.
+        ASSERT(res);
+    }
+
+    EnterCriticalSection (&mutex.m_internalMutex);
+
+    return !timedOut;
+}
+
+void PlatformCondition::signal(bool unblockAll)
+{
+    unsigned signalsToIssue = 0;
+
+    DWORD res = WaitForSingleObject(m_unblockLock, INFINITE);
+    ASSERT(res == WAIT_OBJECT_0);
+
+    if (m_waitersToUnblock) { // the gate is already closed
+        if (!m_waitersBlocked) { // no-op
+            res = ReleaseMutex(m_unblockLock);
+            ASSERT(res);
+            return;
+        }
+
+        if (unblockAll) {
+            signalsToIssue = m_waitersBlocked;
+            m_waitersToUnblock += m_waitersBlocked;
+            m_waitersBlocked = 0;
+        } else {
+            signalsToIssue = 1;
+            ++m_waitersToUnblock;
+            --m_waitersBlocked;
+        }
+    } else if (m_waitersBlocked > m_waitersGone) {
+        res = WaitForSingleObject(m_blockLock, INFINITE); // Close the gate.
+        ASSERT(res == WAIT_OBJECT_0);
+        if (m_waitersGone != 0) {
+            m_waitersBlocked -= m_waitersGone;
+            m_waitersGone = 0;
+        }
+        if (unblockAll) {
+            signalsToIssue = m_waitersBlocked;
+            m_waitersToUnblock = m_waitersBlocked;
+            m_waitersBlocked = 0;
+        } else {
+            signalsToIssue = 1;
+            m_waitersToUnblock = 1;
+            --m_waitersBlocked;
+        }
+    } else { // No-op.
+        res = ReleaseMutex(m_unblockLock);
+        ASSERT(res);
+        return;
+    }
+
+    res = ReleaseMutex(m_unblockLock);
+    ASSERT(res);
+
+    if (signalsToIssue) {
+        res = ReleaseSemaphore(m_blockQueue, signalsToIssue, 0);
+        ASSERT(res);
+    }
+}
+
+static const long MaxSemaphoreCount = static_cast<long>(~0UL >> 1);
+
+ThreadCondition::ThreadCondition()
+{
+    m_condition.m_waitersGone = 0;
+    m_condition.m_waitersBlocked = 0;
+    m_condition.m_waitersToUnblock = 0;
+    m_condition.m_blockLock = CreateSemaphore(0, 1, 1, 0);
+    m_condition.m_blockQueue = CreateSemaphore(0, 0, MaxSemaphoreCount, 0);
+    m_condition.m_unblockLock = CreateMutex(0, 0, 0);
+
+    if (!m_condition.m_blockLock || !m_condition.m_blockQueue || !m_condition.m_unblockLock) {
+        if (m_condition.m_blockLock)
+            CloseHandle(m_condition.m_blockLock);
+        if (m_condition.m_blockQueue)
+            CloseHandle(m_condition.m_blockQueue);
+        if (m_condition.m_unblockLock)
+            CloseHandle(m_condition.m_unblockLock);
+    }
+}
+
+ThreadCondition::~ThreadCondition()
+{
+    CloseHandle(m_condition.m_blockLock);
+    CloseHandle(m_condition.m_blockQueue);
+    CloseHandle(m_condition.m_unblockLock);
+}
+
+void ThreadCondition::wait(Mutex& mutex)
+{
+    m_condition.timedWait(mutex.impl(), INFINITE);
+}
+
+bool ThreadCondition::timedWait(Mutex& mutex, double absoluteTime)
+{
+    double currentTime = WTF::currentTime();
+
+    // Time is in the past - return immediately.
+    if (absoluteTime < currentTime)
+        return false;
+
+    // Time is too far in the future (and would overflow unsigned long) - wait forever.
+    if (absoluteTime - currentTime > static_cast<double>(INT_MAX) / 1000.0) {
+        wait(mutex);
+        return true;
+    }
+
+    double intervalMilliseconds = (absoluteTime - currentTime) * 1000.0;
+    return m_condition.timedWait(mutex.impl(), static_cast<unsigned long>(intervalMilliseconds));
+}
+
+void ThreadCondition::signal()
+{
+    m_condition.signal(false); // Unblock only 1 thread.
+}
+
+void ThreadCondition::broadcast()
+{
+    m_condition.signal(true); // Unblock all threads.
+}
+
+} // namespace WTF