QSemaphore处理生产者/消费者模式:
https://blog.csdn.net/qq_41895747/article/details/104102307
main.cpp
#include <QCoreApplication>
#include <QMutex>
#include <QThread>
#include <QWaitCondition>
#include <stdio.h>
const int DataSize = 1000;//数据区大小
const int BufferSize = 80;//缓冲区大小
int buffer[BufferSize];
QWaitCondition bufferEmpty;
QWaitCondition bufferFull;
QMutex mutex;//锁定的互斥量,使用互斥量保证操作的原子性
int numUseBytes=0;//可用字节
int rIndex=0;//当前读取缓冲区的位置
//消费者
class Producer:public QThread{
public:
Producer();
void run();
};
Producer::Producer(){
}
void Producer::run(){
for(int i=0;i<DataSize;i++){
mutex.lock();//锁定互斥量
if(numUseBytes==BufferSize){//检查缓冲区是否已经填满
bufferEmpty.wait(&mutex);//等待缓冲区有空位
}
buffer[i%BufferSize]=numUseBytes;//使用当前缓冲区单元序号填写这个缓冲区单元
++numUseBytes;//可用字节数增一
bufferFull.wakeAll();//唤醒等待缓冲区有可用数据为真的线程
mutex.unlock();//解锁互斥量
}
}
//消费者
class Consumer:public QThread{
public:
Consumer();
void run();
};
Consumer::Consumer(){
}
void Consumer::run(){
forever{
mutex.lock();//锁定互斥量
if(numUseBytes==0){
bufferFull.wait(&mutex);
}
//打印当前线程号、缓冲区位置、缓冲区数据
printf("%ul::[%d]\n",currentThreadId(),rIndex,buffer[rIndex]);//
rIndex=(++rIndex)%BufferSize;//变量循环加一
bufferFull.wakeAll();//唤醒等待缓冲区有可用数据为真的线程
mutex.unlock();//解锁互斥量
}
printf("\n");
}
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
Producer producer;
Consumer consumerA;
Consumer consumerB;
//启动消费者和生产者的线程
producer.start();
consumerA.start();
consumerB.start();
//等待消费者执行完毕后退出
producer.wait();
consumerA.wait();
consumerB.wait();
return a.exec();
}
.pro
QT += core
QT -= gui
CONFIG += c++11
TARGET = WaitCondition
CONFIG += console
CONFIG -= app_bundle
TEMPLATE = app
SOURCES += main.cpp
# The following define makes your compiler emit warnings if you use
# any feature of Qt which as been marked deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS
# You can also make your code fail to compile if you use deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000 # disables all the APIs deprecated before Qt 6.0.0