pool

搞笑mempool

 

class aa
{
public:
 aa()
 {
  x = 577;
  y = 66;
  z = 5666.54;
 }
 virtual void haha(){}
 int x;
 int y;
 double z;
};

class bb : public aa
{
public:
 void haha()
 {
  x = 555555;
 }
};

 

#define POOL_MAX  100000
int g_nIndex = 0;
char g_szBuffer[POOL_MAX];

 

template<class T>
class CMemPool : public T
{
public:
 void *operator new(std::size_t size)
 {
  if((g_nIndex + size) > POOL_MAX)
   return NULL;

  void* p = (void*)(g_szBuffer + g_nIndex);

        g_nIndex = g_nIndex + size;

  return p;
 }
 void  operator delete (void   *)
 {
 }
};

class CMemPoolImpl
{
public:
  template<class T>
  static T* malloc()
  {
   CMemPool<T>* p = new CMemPool<T>;

   return (T*) p;
  }
 
  template<class T>
  static void free(T* t)
  {
   CMemPool<T>* p = (CMemPool<T> *)t;

   delete p;
  }
};

 

 

int _tmain(int argc, _TCHAR* argv[])
{
 aa* p = CMemPoolImpl::malloc<bb>();
 p->haha();

 return 0;
}