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Diffstat (limited to 'WebCore/platform/win/MutexWin.cpp')
-rw-r--r-- | WebCore/platform/win/MutexWin.cpp | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/WebCore/platform/win/MutexWin.cpp b/WebCore/platform/win/MutexWin.cpp new file mode 100644 index 0000000..41d7fe4 --- /dev/null +++ b/WebCore/platform/win/MutexWin.cpp @@ -0,0 +1,83 @@ +/* + * Copyright (C) 2007 Apple Inc. All rights reserved. + * Copyright (C) 2007 Brent Fulgham + * + * 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. + */ +#include "config.h" +#include "Threading.h" + +namespace WebCore { + +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); +} + +} // namespace WebCore |