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39
40#ifndef QT3DCORE_QBOUNDEDCIRCULARBUFFER_P_H
41#define QT3DCORE_QBOUNDEDCIRCULARBUFFER_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists for the convenience
48// of other Qt classes. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <QtCore/QReadWriteLock>
55#include <QtCore/QReadLocker>
56#include <QtCore/QSemaphore>
57#include <QtCore/QtGlobal>
58
59#include <Qt3DCore/private/qcircularbuffer_p.h>
60
61QT_BEGIN_NAMESPACE
62
63namespace Qt3DCore {
64
65template <class T>
66class QBoundedCircularBuffer
67{
68public:
69 explicit QBoundedCircularBuffer(int capacity_)
70 : m_free( capacity_ ),
71 m_used( capacity_ ),
72 m_buffer( capacity_ )
73 {
74 m_used.acquire(n: capacity_);
75 }
76
77 int capacity() const { return m_buffer.capacity(); }
78 int freeSize() const { return m_free.available(); }
79 int size() const { return m_used.available(); }
80 bool isFull() const { return m_free.available() == 0; }
81 bool isEmpty() const { return m_used.available() == 0; }
82
83 void push_back(const T &value)
84 {
85 m_free.acquire();
86 QWriteLocker locker(&m_lock);
87 m_buffer.append(value);
88 locker.unlock();
89 m_used.release();
90 }
91
92 void push(const T &t) { push_back(value: t); }
93 void append(const T &t) { push_back(value: t); }
94
95 T pop_front()
96 {
97 m_used.acquire();
98 QWriteLocker locker(&m_lock);
99 T value = m_buffer.first();
100 m_buffer.remove(0);
101 locker.unlock();
102 m_free.release();
103 return value;
104 }
105
106 T pop() { return pop_front(); }
107 T takeFirst() { return pop_front(); }
108
109 void clear()
110 {
111 QWriteLocker locker(&m_lock);
112 m_buffer.clear();
113 int used = m_used.available();
114 m_free.release(n: used);
115 m_used.acquire(n: used);
116 }
117
118 T at(int i) const
119 {
120 QReadLocker readLocker(&m_lock);
121 return m_buffer.at(i);
122 }
123
124 T front() const
125 {
126 QReadLocker readLocker(&m_lock);
127 return m_buffer.front();
128 }
129
130 T back() const
131 {
132 QReadLocker readLocker(&m_lock);
133 return m_buffer.back();
134 }
135
136protected:
137 Q_DISABLE_COPY(QBoundedCircularBuffer)
138
139 QSemaphore m_free;
140 QSemaphore m_used;
141 QCircularBuffer<T> m_buffer;
142 mutable QReadWriteLock m_lock;
143};
144
145} //Qt3D
146
147QT_END_NAMESPACE
148
149#endif // QT3DCORE_QBOUNDEDCIRCULARBUFFER_P_H
150

source code of qt3d/src/core/resources/qboundedcircularbuffer_p.h