--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/JavaScriptCore/wtf/ThreadingWin.cpp Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,484 @@
+/*
+ * 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"
+#if !USE(PTHREADS) && OS(WINDOWS)
+#include "ThreadSpecific.h"
+#endif
+#if !OS(WINCE)
+#include <process.h>
+#endif
+#if HAVE(ERRNO_H)
+#include <errno.h>
+#else
+#define NO_ERRNO
+#endif
+#include <windows.h>
+#include <wtf/CurrentTime.h>
+#include <wtf/HashMap.h>
+#include <wtf/MathExtras.h>
+#include <wtf/RandomNumberSeed.h>
+
+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);
+}
+
+struct ThreadFunctionInvocation {
+ ThreadFunctionInvocation(ThreadFunction function, void* data) : function(function), data(data) {}
+
+ ThreadFunction function;
+ void* data;
+};
+
+static unsigned __stdcall wtfThreadEntryPoint(void* param)
+{
+ ThreadFunctionInvocation invocation = *static_cast<ThreadFunctionInvocation*>(param);
+ delete 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;
+ ThreadFunctionInvocation* invocation = 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, 0, (LPDWORD)&threadIdentifier);
+#else
+ HANDLE threadHandle = reinterpret_cast<HANDLE>(_beginthreadex(0, 0, wtfThreadEntryPoint, invocation, 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 defined(NO_ERRNO)
+ 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;
+ }
+
+ 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);
+}
+
+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