| /**************************************************************************** |
| ** |
| ** Copyright (C) 2015 The Qt Company Ltd. |
| ** Contact: http://www.qt.io/licensing/ |
| ** |
| ** This file is part of the QtCore module of the Qt Toolkit. |
| ** |
| ** $QT_BEGIN_LICENSE:LGPL21$ |
| ** Commercial License Usage |
| ** Licensees holding valid commercial Qt licenses may use this file in |
| ** accordance with the commercial license agreement provided with the |
| ** Software or, alternatively, in accordance with the terms contained in |
| ** a written agreement between you and The Qt Company. For licensing terms |
| ** and conditions see http://www.qt.io/terms-conditions. For further |
| ** information use the contact form at http://www.qt.io/contact-us. |
| ** |
| ** 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 or version 3 as published by the Free |
| ** Software Foundation and appearing in the file LICENSE.LGPLv21 and |
| ** LICENSE.LGPLv3 included in the packaging of this file. Please review the |
| ** following information to ensure the GNU Lesser General Public License |
| ** requirements will be met: https://www.gnu.org/licenses/lgpl.html and |
| ** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. |
| ** |
| ** As a special exception, The Qt Company gives you certain additional |
| ** rights. These rights are described in The Qt Company LGPL Exception |
| ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. |
| ** |
| ** $QT_END_LICENSE$ |
| ** |
| ****************************************************************************/ |
| |
| #ifndef QMUTEX_H |
| #define QMUTEX_H |
| |
| #include <QtCore/qglobal.h> |
| #include <QtCore/qatomic.h> |
| #include <new> |
| |
| QT_BEGIN_NAMESPACE |
| |
| |
| #if !defined(QT_NO_THREAD) && !defined(Q_QDOC) |
| |
| #ifdef Q_OS_LINUX |
| # define QT_MUTEX_LOCK_NOEXCEPT Q_DECL_NOTHROW |
| #else |
| # define QT_MUTEX_LOCK_NOEXCEPT |
| #endif |
| |
| class QMutexData; |
| |
| class Q_CORE_EXPORT QBasicMutex |
| { |
| public: |
| inline void lock() QT_MUTEX_LOCK_NOEXCEPT { |
| if (!fastTryLock()) |
| lockInternal(); |
| } |
| |
| inline void unlock() Q_DECL_NOTHROW { |
| Q_ASSERT(d_ptr.load()); //mutex must be locked |
| if (!fastTryUnlock()) |
| unlockInternal(); |
| } |
| |
| bool tryLock() Q_DECL_NOTHROW { |
| return fastTryLock(); |
| } |
| |
| bool isRecursive(); //### Qt6: mark const |
| |
| private: |
| inline bool fastTryLock() Q_DECL_NOTHROW { |
| return d_ptr.testAndSetAcquire(0, dummyLocked()); |
| } |
| inline bool fastTryUnlock() Q_DECL_NOTHROW { |
| return d_ptr.testAndSetRelease(dummyLocked(), 0); |
| } |
| inline bool fastTryLock(QMutexData *¤t) Q_DECL_NOTHROW { |
| return d_ptr.testAndSetAcquire(0, dummyLocked(), current); |
| } |
| inline bool fastTryUnlock(QMutexData *¤t) Q_DECL_NOTHROW { |
| return d_ptr.testAndSetRelease(dummyLocked(), 0, current); |
| } |
| |
| void lockInternal() QT_MUTEX_LOCK_NOEXCEPT; |
| bool lockInternal(int timeout) QT_MUTEX_LOCK_NOEXCEPT; |
| void unlockInternal() Q_DECL_NOTHROW; |
| |
| QBasicAtomicPointer<QMutexData> d_ptr; |
| static inline QMutexData *dummyLocked() { |
| return reinterpret_cast<QMutexData *>(quintptr(1)); |
| } |
| |
| friend class QMutex; |
| friend class QMutexData; |
| }; |
| |
| class Q_CORE_EXPORT QMutex : public QBasicMutex { |
| public: |
| enum RecursionMode { NonRecursive, Recursive }; |
| explicit QMutex(RecursionMode mode = NonRecursive); |
| ~QMutex(); |
| |
| void lock() QT_MUTEX_LOCK_NOEXCEPT; |
| bool tryLock(int timeout = 0) QT_MUTEX_LOCK_NOEXCEPT; |
| void unlock() Q_DECL_NOTHROW; |
| |
| using QBasicMutex::isRecursive; |
| |
| private: |
| Q_DISABLE_COPY(QMutex) |
| friend class QMutexLocker; |
| }; |
| |
| class Q_CORE_EXPORT QMutexLocker |
| { |
| public: |
| inline explicit QMutexLocker(QBasicMutex *m) QT_MUTEX_LOCK_NOEXCEPT |
| { |
| Q_ASSERT_X((reinterpret_cast<quintptr>(m) & quintptr(1u)) == quintptr(0), |
| "QMutexLocker", "QMutex pointer is misaligned"); |
| val = quintptr(m); |
| if (Q_LIKELY(m)) { |
| // call QMutex::lock() instead of QBasicMutex::lock() |
| static_cast<QMutex *>(m)->lock(); |
| val |= 1; |
| } |
| } |
| inline ~QMutexLocker() { unlock(); } |
| |
| inline void unlock() Q_DECL_NOTHROW |
| { |
| if ((val & quintptr(1u)) == quintptr(1u)) { |
| val &= ~quintptr(1u); |
| mutex()->unlock(); |
| } |
| } |
| |
| inline void relock() QT_MUTEX_LOCK_NOEXCEPT |
| { |
| if (val) { |
| if ((val & quintptr(1u)) == quintptr(0u)) { |
| mutex()->lock(); |
| 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; |
| }; |
| |
| #else // QT_NO_THREAD or Q_QDOC |
| |
| class Q_CORE_EXPORT QMutex |
| { |
| public: |
| enum RecursionMode { NonRecursive, Recursive }; |
| |
| inline explicit QMutex(RecursionMode mode = NonRecursive) Q_DECL_NOTHROW { Q_UNUSED(mode); } |
| |
| inline void lock() Q_DECL_NOTHROW {} |
| inline bool tryLock(int timeout = 0) Q_DECL_NOTHROW { Q_UNUSED(timeout); return true; } |
| inline void unlock() Q_DECL_NOTHROW {} |
| inline bool isRecursive() Q_DECL_NOTHROW { return true; } |
| |
| private: |
| Q_DISABLE_COPY(QMutex) |
| }; |
| |
| class Q_CORE_EXPORT QMutexLocker |
| { |
| public: |
| inline explicit QMutexLocker(QMutex *) Q_DECL_NOTHROW {} |
| inline ~QMutexLocker() Q_DECL_NOTHROW {} |
| |
| inline void unlock() Q_DECL_NOTHROW {} |
| void relock() Q_DECL_NOTHROW {} |
| inline QMutex *mutex() const Q_DECL_NOTHROW { return Q_NULLPTR; } |
| |
| private: |
| Q_DISABLE_COPY(QMutexLocker) |
| }; |
| |
| typedef QMutex QBasicMutex; |
| |
| #endif // QT_NO_THREAD or Q_QDOC |
| |
| QT_END_NAMESPACE |
| |
| #endif // QMUTEX_H |