Initial import from the monolithic Qt.

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Branched from the monolithic repo, Qt master branch, at commit
896db169ea224deb96c59ce8af800d019de63f12

1 files changed, 248 insertions, 0 deletions

diff --git a/src/corelib/thread/qmutex.h b/src/corelib/thread/qmutex.h
new file mode 100644
index 0000000000..5f75195b4e
--- /dev/null
+++ b/src/corelib/thread/qmutex.h
@@ -0,0 +1,248 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QMUTEX_H
+#define QMUTEX_H
+
+#include <QtCore/qglobal.h>
+#include <QtCore/qatomic.h>
+#include <new>
+
+QT_BEGIN_HEADER
+
+QT_BEGIN_NAMESPACE
+
+QT_MODULE(Core)
+
+#ifndef QT_NO_THREAD
+
+class QAtomicInt;
+class QMutexData;
+
+class Q_CORE_EXPORT QMutex
+{
+    friend class QWaitCondition;
+    friend class QWaitConditionPrivate;
+
+public:
+    enum RecursionMode { NonRecursive, Recursive };
+
+    explicit QMutex(RecursionMode mode = NonRecursive);
+    ~QMutex();
+
+    void lock();     //### Qt5: make inline;
+    inline void lockInline();
+    bool tryLock();  //### Qt5: make inline;
+    bool tryLock(int timeout);
+    inline bool tryLockInline();
+    void unlock();     //### Qt5: make inline;
+    inline void unlockInline();
+
+#if defined(QT3_SUPPORT)
+    inline QT3_SUPPORT bool locked()
+    {
+        if (!tryLock())
+            return true;
+        unlock();
+        return false;
+    }
+    inline QT3_SUPPORT_CONSTRUCTOR QMutex(bool recursive)
+    {
+        new (this) QMutex(recursive ? Recursive : NonRecursive);
+    }
+#endif
+
+private:
+    void lockInternal();
+    void unlockInternal();
+    Q_DISABLE_COPY(QMutex)
+
+    QMutexData *d;
+};
+
+class Q_CORE_EXPORT QMutexLocker
+{
+public:
+    inline explicit QMutexLocker(QMutex *m)
+    {
+        Q_ASSERT_X((reinterpret_cast<quintptr>(m) & quintptr(1u)) == quintptr(0),
+                   "QMutexLocker", "QMutex pointer is misaligned");
+        if (m) {
+            m->lockInline();
+            val = reinterpret_cast<quintptr>(m) | quintptr(1u);
+        } else {
+            val = 0;
+        }
+    }
+    inline ~QMutexLocker() { unlock(); }
+
+    inline void unlock()
+    {
+        if ((val & quintptr(1u)) == quintptr(1u)) {
+            val &= ~quintptr(1u);
+            mutex()->unlockInline();
+        }
+    }
+
+    inline void relock()
+    {
+        if (val) {
+            if ((val & quintptr(1u)) == quintptr(0u)) {
+                mutex()->lockInline();
+                val |= quintptr(1u);
+            }
+        }
+    }
+
+#if defined(Q_CC_MSVC)
+#pragma warning( push )
+#pragma warning( disable : 4312 ) // ignoring the warning from /Wp64
+#endif
+
+    inline QMutex *mutex() const
+    {
+        return reinterpret_cast<QMutex *>(val & ~quintptr(1u));
+    }
+
+#if defined(Q_CC_MSVC)
+#pragma warning( pop )
+#endif
+
+private:
+    Q_DISABLE_COPY(QMutexLocker)
+
+    quintptr val;
+};
+
+class QMutexData
+{
+    public:
+        QAtomicInt contenders;
+        const uint recursive : 1;
+        uint reserved : 31;
+    protected:
+        QMutexData(QMutex::RecursionMode mode);
+        ~QMutexData();
+};
+
+#ifdef QT_NO_DEBUG
+inline void QMutex::unlockInline()
+{
+    if (d->recursive) {
+        unlock();
+    } else if (!d->contenders.testAndSetRelease(1, 0)) {
+        unlockInternal();
+    }
+}
+
+inline bool QMutex::tryLockInline()
+{
+    if (d->recursive) {
+        return tryLock();
+    } else {
+        return d->contenders.testAndSetAcquire(0, 1);
+    }
+}
+
+inline void QMutex::lockInline()
+{
+    if (d->recursive) {
+        lock();
+    } else if(!tryLockInline()) {
+        lockInternal();
+    }
+}
+#else // QT_NO_DEBUG
+//in debug we do not use inline calls in order to allow debugging tools
+// to hook the mutex locking functions.
+inline void QMutex::unlockInline() { unlock(); }
+inline bool QMutex::tryLockInline() { return tryLock(); }
+inline void QMutex::lockInline() { lock(); }
+#endif // QT_NO_DEBUG
+
+
+#else // QT_NO_THREAD
+
+
+class Q_CORE_EXPORT QMutex
+{
+public:
+    enum RecursionMode { NonRecursive, Recursive };
+
+    inline explicit QMutex(RecursionMode mode = NonRecursive) { Q_UNUSED(mode); }
+    inline ~QMutex() {}
+
+    static inline void lock() {}
+    static inline void lockInline() {}
+    static inline bool tryLock(int timeout = 0) { Q_UNUSED(timeout); return true; }
+    static inline bool tryLockInline() { return true; }
+    static inline void unlock() {}
+    static inline void unlockInline() {}
+
+#if defined(QT3_SUPPORT)
+    static inline QT3_SUPPORT bool locked() { return false; }
+#endif
+
+private:
+    Q_DISABLE_COPY(QMutex)
+};
+
+class Q_CORE_EXPORT QMutexLocker
+{
+public:
+    inline explicit QMutexLocker(QMutex *) {}
+    inline ~QMutexLocker() {}
+
+    static inline void unlock() {}
+    static void relock() {}
+    static inline QMutex *mutex() { return 0; }
+
+private:
+    Q_DISABLE_COPY(QMutexLocker)
+};
+
+#endif // QT_NO_THREAD
+
+QT_END_NAMESPACE
+
+QT_END_HEADER
+
+#endif // QMUTEX_H