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50
51#include <QtCore>
52
53#include <stdio.h>
54#include <stdlib.h>
55
56//! [0]
57const int DataSize = 100000;
58
59const int BufferSize = 8192;
60char buffer[BufferSize];
61
62QWaitCondition bufferNotEmpty;
63QWaitCondition bufferNotFull;
64QMutex mutex;
65int numUsedBytes = 0;
66//! [0]
67
68//! [1]
69class Producer : public QThread
70//! [1] //! [2]
71{
72public:
73 Producer(QObject *parent = NULL) : QThread(parent)
74 {
75 }
76
77 void run() override
78 {
79 for (int i = 0; i < DataSize; ++i) {
80 mutex.lock();
81 if (numUsedBytes == BufferSize)
82 bufferNotFull.wait(lockedMutex: &mutex);
83 mutex.unlock();
84
85 buffer[i % BufferSize] = "ACGT"[QRandomGenerator::global()->bounded(highest: 4)];
86
87 mutex.lock();
88 ++numUsedBytes;
89 bufferNotEmpty.wakeAll();
90 mutex.unlock();
91 }
92 }
93};
94//! [2]
95
96//! [3]
97class Consumer : public QThread
98//! [3] //! [4]
99{
100 Q_OBJECT
101public:
102 Consumer(QObject *parent = NULL) : QThread(parent)
103 {
104 }
105
106 void run() override
107 {
108 for (int i = 0; i < DataSize; ++i) {
109 mutex.lock();
110 if (numUsedBytes == 0)
111 bufferNotEmpty.wait(lockedMutex: &mutex);
112 mutex.unlock();
113
114 fprintf(stderr, format: "%c", buffer[i % BufferSize]);
115
116 mutex.lock();
117 --numUsedBytes;
118 bufferNotFull.wakeAll();
119 mutex.unlock();
120 }
121 fprintf(stderr, format: "\n");
122 }
123
124signals:
125 void stringConsumed(const QString &text);
126};
127//! [4]
128
129
130//! [5]
131int main(int argc, char *argv[])
132//! [5] //! [6]
133{
134 QCoreApplication app(argc, argv);
135 Producer producer;
136 Consumer consumer;
137 producer.start();
138 consumer.start();
139 producer.wait();
140 consumer.wait();
141 return 0;
142}
143//! [6]
144
145#include "waitconditions.moc"
146

source code of qtbase/examples/corelib/threads/waitconditions/waitconditions.cpp