cpp-learn/countptr.h at master · tushargosavi/cpp-learn · GitHub

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#ifndef COUNTEDPTR_H
#define COUNTEDPTR_H

template<typename T>
class CountedPtr {
private :
  T* ptr;
  long *count;
public :
  explicit CountedPtr(T *p = 0) : ptr(p), count(new long(1)) { }

  CountedPtr(const CountedPtr<T>& p) throw()
    : ptr(p.ptr), count(p.count) {
    ++*count;
  }

  ~CountedPtr() throw () {
    dispose();
  }

  CountedPtr<T>& operator = (const CountedPtr<T>& p) throw () {
    if (this != &p) {
      dispose();
      ptr = p.ptr;
      count = p.count;
      ++*count;
    }
    return *this;
  }

  T& operator*() const throw () {
    return *ptr;
  }

  T* operator->() const throw () {
    return ptr;
  }

private :
  void dispose() {
    if (--count == 0) {
      delete count;
      delete ptr;
    }
  }
};

#endif