VC2010新增加对多线程的支持类

r囧r小猫 2022-06-16 23:38 191阅读 0赞

临界区的类:Concurrency::critical\_section; 相对应的自动加解锁类 Concurrency::critical\_section::scoped\_lock

读写问题Concurrency::reader\_writer\_lock;写对应的自加解锁Concurrency::reader\_writer\_lock::scoped\_lock;读对应的自加解锁Concurrency::reader\_writer\_lock::scoped\_lock\_read

微软这次添加的类,在boost早已经有了,我总结一下,对应关系是

Concurrency::critical\_section boost::mutex

Concurrency::critical\_section::scoped\_lock boost::scoped\_lock

Concurrency::reader\_writer\_lockboost::shared\_mutex

Concurrency::reader\_writer\_lock::scoped\_lockboost::uniq\_lock<boost::shared\_mutex>

Concurrency::reader\_writer\_lock::scoped\_lock\_readboost::shared\_lock<boost::shared\_mutex>

#include <boost/thread.hpp>
    #include <concrt.h>
    #include <iostream>
    #include <list>
    using namespace std;
    void Write(std::list<int> &_list,Concurrency::reader_writer_lock &rwLock,bool bAdd)
    {
        for (int i(0);i<10;++i,Sleep(bAdd? 50:10))
        {
            Concurrency::reader_writer_lock::scoped_lock _lock(rwLock);
            if(bAdd)
                _list.insert(_list.begin(),i);
            else
            {
                if(_list.size())
                    _list.erase(_list.begin());
            }
        }
    }
    void Read(std::list<int> &_list,Concurrency::reader_writer_lock &rwLock)
    {
        for (int i(0);i<10;++i,Sleep(100))
        {
            Concurrency::reader_writer_lock::scoped_lock_read _rLock(rwLock);
            for_each(_list.begin(),_list.end(),[](int i){cout<<i<<ends;});
            cout<<endl;
        }
    }
    void fnCS(Concurrency::critical_section &io_lock)
    {
        Concurrency::critical_section::scoped_lock sLock(io_lock);
        for (int i(0);i<10;++i)
            cout<<i<<ends;
        cout<<endl;
    }
    int main(int argc, char* argv[])
    {
        Concurrency::critical_section io_lock;//io 互斥锁
        boost::thread_group tg;
        tg.add_thread(new boost::thread(fnCS,boost::ref(io_lock)));
        tg.add_thread(new boost::thread(fnCS,boost::ref(io_lock)));
        tg.join_all();
        std::list<int> _list;
        Concurrency::reader_writer_lock rwLock;
        boost::thread_group tg2;
        tg2.add_thread(new boost::thread(Write,boost::ref(_list),boost::ref(rwLock),true));//添加
        tg2.add_thread(new boost::thread(Read,boost::ref(_list),boost::ref(rwLock)));//读取
        tg2.add_thread(new boost::thread(Write,boost::ref(_list),boost::ref(rwLock),false));//删除
        tg2.add_thread(new boost::thread(Read,boost::ref(_list),boost::ref(rwLock)));//读取
        tg2.join_all();//等待全部结束
    };

VC自带的读写锁，非重入的类型，如果发生，将抛出improper\_lock异常。

typedef Concurrency::reader\_writer\_lockrwmutex;  
typedef Concurrency::reader\_writer\_lock::scoped\_lock\_readreadLock;  
typedef Concurrency::reader\_writer\_lock::scoped\_lockwriteLock;

rwmutex g\_rwLock;  
void testThread1()//运行木问题  
\{  
readLock r(g\_rwLock);  
readLock r2(g\_rwLock);  
\}  
void testThread2()  
\{  
writeLock w(g\_rwLock);  
writeLock w2(g\_rwLock);//发生异常  
\}  
void testThread3()  
\{  
writeLock r(g\_rwLock);  
readLock r2(g\_rwLock);//发生异常  
\}