Util.h:

#define CREATE_SINGLETON_POINTER(CLASS,INSTANCE,MUTEX) if (NULL == INSTANCE) \                                                    { \                                                        MUTEX.lock(); \                                                        if (NULL == INSTANCE) \                                                        { \                                                            INSTANCE = new CLASS(); \                                                        } \                                                        MUTEX.unlock(); \                                                    }#define DESTORY_SINGLETON_POINTER(INSTANCE) if (NULL != INSTANCE) \                                            { \                                                delete INSTANCE; \                                                INSTANCE = NULL; \                                            }

 

Foo.cpp:

#include "Foo.h"#include 
     
      std::mutex instanceMutex;Foo* Foo::instance = NULL;Foo* Foo::getInstance(){    CREATE_SINGLETON_POINTER(Foo, instance, instanceMutex);    return instance;} Foo::~Foo() {
        DESTORY_SINGLETON_POINTER(instance); }