版权声明:本文为博主原创文章,遵循 CC 4.0 BY-SA 版权协议,转载请附上原文出处链接和本声明。
本文链接:https://blog.csdn.net/wsj18808050/article/details/51603006
在GUN标准中,提供了__thread关键字,配合static后,可以实现让一个线程拥有自己的全局变量。
我对__thread进行了简单的封装,可以用于存储class。并且防止了内存泄露(如果使用Qt线程类)。
测试中,我一共开启了两个线程,从输出可以得知每个线程都拥有自己的变量,并且在线程退出后被正常释放。
测试代码:
// Qt lib import
#include <QtCore>
#include <QtConcurrent>
class MyClass
{
public:
MyClass()
{
qDebug() << "MyClass" << this << QThread::currentThread();
}
~MyClass()
{
qDebug() << "~MyClass" << this << QThread::currentThread();
}
};
template< class T >
class ThreadStore
{
public:
T &getQuote()
{
if ( !t )
{
t = new T;
auto thread = qobject_cast< QThread * >( QThread::currentThread() );
if ( thread && thread->isRunning() )
{
QObject::connect( QThread::currentThread(), &QThread::finished, [ this ]()
{
if ( t )
{
delete t;
t = nullptr;
}
} );
}
}
return *t;
}
private:
T *t;
};
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
auto myTest = []()
{
static __thread ThreadStore< MyClass > threadStore;
auto &myData = threadStore.getQuote();
qDebug() << "myData:" << &myData;
QThread::sleep( 1 );
};
QThreadPool::globalInstance()->setMaxThreadCount( 2 );
QtConcurrent::run( myTest );
QtConcurrent::run( myTest );
QtConcurrent::run( myTest );
QtConcurrent::run( myTest );
QThreadPool::globalInstance()->waitForDone();
return a.exec();
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
输出结果:
MyClass 0x7fe842e09b10 QThread(0x7fe842d0cbe0, name = "Thread (pooled)")
MyClass 0x7fe842c1d6a0 QThread(0x7fe842d0df60, name = "Thread (pooled)")
myData: 0x7fe842e09b10
myData: 0x7fe842c1d6a0
myData: 0x7fe842e09b10
myData: 0x7fe842c1d6a0
~MyClass 0x7fe842e09b10 QThread(0x7fe842d0cbe0, name = "Thread (pooled)")
~MyClass 0x7fe842c1d6a0 QThread(0x7fe842d0df60, name = "Thread (pooled)")
――――――――――――――――
版权声明:本文为CSDN博主「Jason188080501」的原创文章,遵循 CC 4.0 BY-SA 版权协议,转载请附上原文出处链接及本声明。
原文链接:https://blog.csdn.net/wsj18808050/article/details/51603006
来源:博客园
作者:findumars
链接:https://www.cnblogs.com/findumars/p/11553550.html