Safe C++

Appendix H. Source Code for the file scpp_scopedptr.hpp

#ifndef __SCPP_SCOPEDPTR_HPP_INCLUDED__
#define __SCPP_SCOPEDPTR_HPP_INCLUDED__

#include "scpp_assert.hpp"

namespace scpp {

// Scoped pointer, takes ownership of an object, could not be copied.
template <typename T>
class ScopedPtr {
  public:

  explicit ScopedPtr(T* p = NULL)
  : ptr_(p) {
  }

  ScopedPtr<T>& operator=(T* p) {
    if(ptr_ != p)
    {
      delete ptr_;
      ptr_ = p;
    }

    return *this;
  }

  ~ScopedPtr() {
    delete ptr_;
  }

  T* Get() const {
    return ptr_;
  }

  T* operator->() const
  {
    SCPP_TEST_ASSERT(ptr_ != NULL, "Attempt to use operator -> on NULL pointer.");
    return ptr_;
  }

  T& operator* () const {
    SCPP_TEST_ASSERT(ptr_ != NULL, "Attempt to use operator * on NULL pointer.");
    return *ptr_;
  }

  // Release ownership of the object to the caller.
  T* Release() {
    T* p = ptr_;
    ptr_ = NULL;
    return p;
  }

private:
  T*  ptr_;

  // Copy is prohibited:
  ScopedPtr(const ScopedPtr<T>& rhs);
  ScopedPtr<T>& operator=(const ScopedPtr<T>& rhs);
};

} // namespace scpp

#endif // __SCPP_SCOPEDPTR_HPP_INCLUDED__