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40
41#ifndef QREADWRITELOCK_P_H
42#define QREADWRITELOCK_P_H
43
44//
45// W A R N I N G
46// -------------
47//
48// This file is not part of the Qt API. It exists for the convenience
49// of the implementation. This header file may change from version to
50// version without notice, or even be removed.
51//
52// We mean it.
53//
54
55#include <QtCore/private/qglobal_p.h>
56#include <QtCore/qhash.h>
57#include <QtCore/qwaitcondition.h>
58
59QT_REQUIRE_CONFIG(thread);
60
61QT_BEGIN_NAMESPACE
62
63class QReadWriteLockPrivate
64{
65public:
66 explicit QReadWriteLockPrivate(bool isRecursive = false)
67 : recursive(isRecursive) {}
68
69 QMutex mutex;
70 QWaitCondition writerCond;
71 QWaitCondition readerCond;
72 int readerCount = 0;
73 int writerCount = 0;
74 int waitingReaders = 0;
75 int waitingWriters = 0;
76 const bool recursive;
77
78 //Called with the mutex locked
79 bool lockForWrite(int timeout);
80 bool lockForRead(int timeout);
81 void unlock();
82
83 //memory management
84 int id = 0;
85 void release();
86 static QReadWriteLockPrivate *allocate();
87
88 // Recusive mutex handling
89 Qt::HANDLE currentWriter = {};
90 QHash<Qt::HANDLE, int> currentReaders;
91
92 // called with the mutex unlocked
93 bool recursiveLockForWrite(int timeout);
94 bool recursiveLockForRead(int timeout);
95 void recursiveUnlock();
96};
97
98QT_END_NAMESPACE
99
100#endif // QREADWRITELOCK_P_H
101