Singleton 单例模板

 // singleton.h

 #ifndef SINGLETON_H
 #define SINGLETON_H

 // 单例基类模板
 template <class T>
 class Singleton
 {
 public:
     static T& give_me()
     {
         static T s_inst;
         return s_inst;
     }

 private:
     // 禁止实现拷贝构造与拷贝赋值函数
     explicit Singleton(const Singleton<T> &rhs);
     Singleton<T>& operator = (const Singleton<T> &rhs);

 protected:
     explicit Singleton()    {}
     virtual ~Singleton()    {}
 };

 #endif // SINGLETON_H

 #ifndef TEST_MANAGER_H
 #define TEST_MANAGER_H

 #include "singleton.h"

 class TestManager : public Singleton<TestManager>
 {
     friend class Singleton<TestManager>;

 private:
     explicit TestManager();
     virtual ~TestManager();

 public:
     void func();
 };

 #endif // TEST_MANAGER_H