Move Source/WTF/wtf to Source/wtf

Source/WTF/wtf/ThreadRestrictionVerifier.h

-/*
- * Copyright (C) 2011 Google 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:
- *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * 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.
- *     * Neither the name of Google Inc. 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 THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT
- * OWNER OR 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 ThreadRestrictionVerifier_h
-#define ThreadRestrictionVerifier_h
-
-#include <wtf/Assertions.h>
-#include <wtf/Threading.h>
-#include <wtf/ThreadingPrimitives.h>
-
-#if HAVE(DISPATCH_H)
-#include <dispatch/dispatch.h>
-#endif
-
-#ifndef NDEBUG
-
-namespace WTF {
-
-// Verifies that a class is used in a way that respects its lack of thread-safety.
-// The default mode is to verify that the object will only be used on a single thread. The
-// thread gets captured when setShared(true) is called.
-// The mode may be changed by calling useMutexMode (or turnOffVerification).
-class ThreadRestrictionVerifier {
-public:
-    ThreadRestrictionVerifier()
-        : m_mode(SingleThreadVerificationMode)
-        , m_shared(false)
-        , m_owningThread(0)
-        , m_mutex(0)
-#if HAVE(DISPATCH_H)
-        , m_owningQueue(0)
-#endif
-    {
-    }
-
-#if HAVE(DISPATCH_H)
-    ~ThreadRestrictionVerifier()
-    {
-        if (m_owningQueue)
-            dispatch_release(m_owningQueue);
-    }
-#endif
-
-    void setMutexMode(Mutex& mutex)
-    {
-        m_mode = MutexVerificationMode;
-        m_mutex = &mutex;
-    }
-
-#if HAVE(DISPATCH_H)
-    void setDispatchQueueMode(dispatch_queue_t queue)
-    {
-        m_mode = SingleDispatchQueueVerificationMode;
-        m_owningQueue = queue;
-        dispatch_retain(m_owningQueue);
-    }
-#endif
-
-    void turnOffVerification()
-    {
-        m_mode = NoVerificationMode;
-    }
-
-    // Indicates that the object may (or may not) be owned by more than one place.
-    void setShared(bool shared)
-    {
-#if !ASSERT_DISABLED
-        bool previouslyShared = m_shared;
-#endif
-        m_shared = shared;
-
-        if (!m_shared)
-            return;
-
-        switch (m_mode) {
-        case SingleThreadVerificationMode:
-            ASSERT(shared != previouslyShared);
-            // Capture the current thread to verify that subsequent ref/deref happen on this thread.
-            m_owningThread = currentThread();
-            return;
-
-#if HAVE(DISPATCH_H)
-        case SingleDispatchQueueVerificationMode:
-#endif
-        case MutexVerificationMode:
-        case NoVerificationMode:
-            return;
-        }
-        ASSERT_NOT_REACHED();
-    }
-
-    // Is it OK to use the object at this moment on the current thread?
-    bool isSafeToUse() const
-    {
-        if (!m_shared)
-            return true;
-
-        switch (m_mode) {
-        case SingleThreadVerificationMode:
-            return m_owningThread == currentThread();
-
-        case MutexVerificationMode:
-            if (!m_mutex->tryLock())
-                return true;
-            m_mutex->unlock();
-            return false;
-
-#if HAVE(DISPATCH_H)
-        case SingleDispatchQueueVerificationMode:
-            return m_owningQueue == dispatch_get_current_queue();
-#endif
-
-        case NoVerificationMode:
-            return true;
-        }
-        ASSERT_NOT_REACHED();
-        return true;
-    }
-
-private:
-    enum VerificationMode {
-        SingleThreadVerificationMode,
-        MutexVerificationMode,
-        NoVerificationMode,
-#if HAVE(DISPATCH_H)
-        SingleDispatchQueueVerificationMode,
-#endif
-    };
-
-    VerificationMode m_mode;
-    bool m_shared;
-
-    // Used by SingleThreadVerificationMode
-    ThreadIdentifier m_owningThread;
-
-    // Used by MutexVerificationMode.
-    Mutex* m_mutex;
-
-#if HAVE(DISPATCH_H)
-    // Used by SingleDispatchQueueVerificationMode.
-    dispatch_queue_t m_owningQueue;
-#endif
-};
-
-}
-
-#endif
-#endif