| /**************************************************************************** |
| ** |
| ** Copyright (C) 2016 The Qt Company Ltd. |
| ** Contact: https://www.qt.io/licensing/ |
| ** |
| ** This file is part of the QtCore module of the Qt Toolkit. |
| ** |
| ** $QT_BEGIN_LICENSE:LGPL$ |
| ** Commercial License Usage |
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| ** GNU Lesser General Public License Usage |
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| ** General Public License version 3 as published by the Free Software |
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| ** packaging of this file. Please review the following information to |
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| ** |
| ** GNU General Public License Usage |
| ** Alternatively, this file may be used under the terms of the GNU |
| ** General Public License version 2.0 or (at your option) the GNU General |
| ** Public license version 3 or any later version approved by the KDE Free |
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| ** $QT_END_LICENSE$ |
| ** |
| ****************************************************************************/ |
| |
| #ifndef QREADWRITELOCK_H |
| #define QREADWRITELOCK_H |
| |
| #include <QtCore/qglobal.h> |
| |
| QT_BEGIN_NAMESPACE |
| |
| |
| #if QT_CONFIG(thread) |
| |
| class QReadWriteLockPrivate; |
| |
| class Q_CORE_EXPORT QReadWriteLock |
| { |
| public: |
| enum RecursionMode { NonRecursive, Recursive }; |
| |
| explicit QReadWriteLock(RecursionMode recursionMode = NonRecursive); |
| ~QReadWriteLock(); |
| |
| void lockForRead(); |
| bool tryLockForRead(); |
| bool tryLockForRead(int timeout); |
| |
| void lockForWrite(); |
| bool tryLockForWrite(); |
| bool tryLockForWrite(int timeout); |
| |
| void unlock(); |
| |
| private: |
| Q_DISABLE_COPY(QReadWriteLock) |
| QAtomicPointer<QReadWriteLockPrivate> d_ptr; |
| |
| enum StateForWaitCondition { LockedForRead, LockedForWrite, Unlocked, RecursivelyLocked }; |
| StateForWaitCondition stateForWaitCondition() const; |
| friend class QWaitCondition; |
| }; |
| |
| #if defined(Q_CC_MSVC) |
| #pragma warning( push ) |
| #pragma warning( disable : 4312 ) // ignoring the warning from /Wp64 |
| #endif |
| |
| class Q_CORE_EXPORT QReadLocker |
| { |
| public: |
| inline QReadLocker(QReadWriteLock *readWriteLock); |
| |
| inline ~QReadLocker() |
| { unlock(); } |
| |
| inline void unlock() |
| { |
| if (q_val) { |
| if ((q_val & quintptr(1u)) == quintptr(1u)) { |
| q_val &= ~quintptr(1u); |
| readWriteLock()->unlock(); |
| } |
| } |
| } |
| |
| inline void relock() |
| { |
| if (q_val) { |
| if ((q_val & quintptr(1u)) == quintptr(0u)) { |
| readWriteLock()->lockForRead(); |
| q_val |= quintptr(1u); |
| } |
| } |
| } |
| |
| inline QReadWriteLock *readWriteLock() const |
| { return reinterpret_cast<QReadWriteLock *>(q_val & ~quintptr(1u)); } |
| |
| private: |
| Q_DISABLE_COPY(QReadLocker) |
| quintptr q_val; |
| }; |
| |
| inline QReadLocker::QReadLocker(QReadWriteLock *areadWriteLock) |
| : q_val(reinterpret_cast<quintptr>(areadWriteLock)) |
| { |
| Q_ASSERT_X((q_val & quintptr(1u)) == quintptr(0), |
| "QReadLocker", "QReadWriteLock pointer is misaligned"); |
| relock(); |
| } |
| |
| class Q_CORE_EXPORT QWriteLocker |
| { |
| public: |
| inline QWriteLocker(QReadWriteLock *readWriteLock); |
| |
| inline ~QWriteLocker() |
| { unlock(); } |
| |
| inline void unlock() |
| { |
| if (q_val) { |
| if ((q_val & quintptr(1u)) == quintptr(1u)) { |
| q_val &= ~quintptr(1u); |
| readWriteLock()->unlock(); |
| } |
| } |
| } |
| |
| inline void relock() |
| { |
| if (q_val) { |
| if ((q_val & quintptr(1u)) == quintptr(0u)) { |
| readWriteLock()->lockForWrite(); |
| q_val |= quintptr(1u); |
| } |
| } |
| } |
| |
| inline QReadWriteLock *readWriteLock() const |
| { return reinterpret_cast<QReadWriteLock *>(q_val & ~quintptr(1u)); } |
| |
| |
| private: |
| Q_DISABLE_COPY(QWriteLocker) |
| quintptr q_val; |
| }; |
| |
| inline QWriteLocker::QWriteLocker(QReadWriteLock *areadWriteLock) |
| : q_val(reinterpret_cast<quintptr>(areadWriteLock)) |
| { |
| Q_ASSERT_X((q_val & quintptr(1u)) == quintptr(0), |
| "QWriteLocker", "QReadWriteLock pointer is misaligned"); |
| relock(); |
| } |
| |
| #if defined(Q_CC_MSVC) |
| #pragma warning( pop ) |
| #endif |
| |
| #else // QT_CONFIG(thread) |
| |
| class Q_CORE_EXPORT QReadWriteLock |
| { |
| public: |
| enum RecursionMode { NonRecursive, Recursive }; |
| inline explicit QReadWriteLock(RecursionMode = NonRecursive) noexcept { } |
| inline ~QReadWriteLock() { } |
| |
| void lockForRead() noexcept { } |
| bool tryLockForRead() noexcept { return true; } |
| bool tryLockForRead(int timeout) noexcept { Q_UNUSED(timeout); return true; } |
| |
| void lockForWrite() noexcept { } |
| bool tryLockForWrite() noexcept { return true; } |
| bool tryLockForWrite(int timeout) noexcept { Q_UNUSED(timeout); return true; } |
| |
| void unlock() noexcept { } |
| |
| private: |
| Q_DISABLE_COPY(QReadWriteLock) |
| }; |
| |
| class Q_CORE_EXPORT QReadLocker |
| { |
| public: |
| inline explicit QReadLocker(QReadWriteLock *) noexcept { } |
| inline ~QReadLocker() noexcept { } |
| |
| void unlock() noexcept { } |
| void relock() noexcept { } |
| QReadWriteLock *readWriteLock() noexcept { return nullptr; } |
| |
| private: |
| Q_DISABLE_COPY(QReadLocker) |
| }; |
| |
| class Q_CORE_EXPORT QWriteLocker |
| { |
| public: |
| inline explicit QWriteLocker(QReadWriteLock *) noexcept { } |
| inline ~QWriteLocker() noexcept { } |
| |
| void unlock() noexcept { } |
| void relock() noexcept { } |
| QReadWriteLock *readWriteLock() noexcept { return nullptr; } |
| |
| private: |
| Q_DISABLE_COPY(QWriteLocker) |
| }; |
| |
| #endif // QT_CONFIG(thread) |
| |
| QT_END_NAMESPACE |
| |
| #endif // QREADWRITELOCK_H |