[C++知识库]单例模式，多线程

#include "thread_pool.h"
#include <iostream>
#include <vector>
#include <thread>
#include <list>
#include <mutex>


using namespace std;
mutex res_mux;
//单例类
class MyCSA
{
	
private:
	MyCSA() {};//私有化的构造函数
	
	static MyCSA *m_instance;//静态成员变量
	mutex mux;
public:
	static MyCSA *getInstance()
	{
		if (m_instance == NULL)//双重锁定，双重检查
		{
			std::unique_lock<mutex>mymux(res_mux);

			if (m_instance == nullptr)
			{
				m_instance = new MyCSA();
				static ReleaseC l;
			}
		}
		
		return m_instance;
	}
	
	class  ReleaseC
	{
	public:
		~ReleaseC()
		{
			if (MyCSA::m_instance)
			{
				delete MyCSA::m_instance;
				MyCSA::m_instance = nullptr;
			}
		}
	};
	
	
};
MyCSA *MyCSA::m_instance = NULL;
int main()
{
	//一.设计模式大概谈
	MyCSA*p_a = MyCSA::getInstance();//创建一个对象，返回该类（MyCSA)对象的指针；
	MyCSA*p_b = MyCSA::getInstance();//创建一个对象，返回该类（MyCSA)对象的指针；


	cout << "I love China!" << endl;//
}