#if !defined(__OBJECT_H) #define __OBJECT_H #include /// Reference counted object base class class Object { public: /// Default constructor Object() { } /// Copy constructor Object(const Object &) : m_refCount(0) {} /// Return the current reference count int getRefCount() const { return m_refCount; }; /// Increase the object's reference count by one void incRef() const { ++m_refCount; } /** \brief Decrease the reference count of * the object and possibly deallocate it. * * The object will automatically be deallocated once * the reference count reaches zero. */ void decRef(bool dealloc = true) const { --m_refCount; if (m_refCount == 0 && dealloc) delete this; else if (m_refCount < 0) throw std::runtime_error("Internal error: reference count < 0!"); } virtual std::string toString() const = 0; protected: /** \brief Virtual protected deconstructor. * (Will only be called by \ref ref) */ virtual ~Object() { } private: mutable std::atomic m_refCount { 0 }; }; /** * \brief Reference counting helper * * The \a ref refeference template is a simple wrapper to store a * pointer to an object. It takes care of increasing and decreasing * the reference count of the object. When the last reference goes * out of scope, the associated object will be deallocated. * * \ingroup libcore */ template class ref { public: /// Create a nullptr reference ref() : m_ptr(nullptr) { std::cout << "Created empty ref" << std::endl; } /// Construct a reference from a pointer ref(T *ptr) : m_ptr(ptr) { std::cout << "Initialized ref from pointer " << ptr<< std::endl; if (m_ptr) ((Object *) m_ptr)->incRef(); } /// Copy constructor ref(const ref &r) : m_ptr(r.m_ptr) { std::cout << "Initialized ref from ref " << r.m_ptr << std::endl; if (m_ptr) ((Object *) m_ptr)->incRef(); } /// Move constructor ref(ref &&r) : m_ptr(r.m_ptr) { std::cout << "Initialized ref with move from ref " << r.m_ptr << std::endl; r.m_ptr = nullptr; } /// Destroy this reference ~ref() { std::cout << "Destructing ref " << m_ptr << std::endl; if (m_ptr) ((Object *) m_ptr)->decRef(); } /// Move another reference into the current one ref& operator=(ref&& r) { std::cout << "Move-assigning ref " << r.m_ptr << std::endl; if (*this == r) return *this; if (m_ptr) ((Object *) m_ptr)->decRef(); m_ptr = r.m_ptr; r.m_ptr = nullptr; return *this; } /// Overwrite this reference with another reference ref& operator=(const ref& r) { std::cout << "Assigning ref " << r.m_ptr << std::endl; if (m_ptr == r.m_ptr) return *this; if (m_ptr) ((Object *) m_ptr)->decRef(); m_ptr = r.m_ptr; if (m_ptr) ((Object *) m_ptr)->incRef(); return *this; } /// Overwrite this reference with a pointer to another object ref& operator=(T *ptr) { std::cout << "Assigning ptr " << ptr << " to ref" << std::endl; if (m_ptr == ptr) return *this; if (m_ptr) ((Object *) m_ptr)->decRef(); m_ptr = ptr; if (m_ptr) ((Object *) m_ptr)->incRef(); return *this; } /// Compare this reference with another reference bool operator==(const ref &r) const { return m_ptr == r.m_ptr; } /// Compare this reference with another reference bool operator!=(const ref &r) const { return m_ptr != r.m_ptr; } /// Compare this reference with a pointer bool operator==(const T* ptr) const { return m_ptr == ptr; } /// Compare this reference with a pointer bool operator!=(const T* ptr) const { return m_ptr != ptr; } /// Access the object referenced by this reference T* operator->() { return m_ptr; } /// Access the object referenced by this reference const T* operator->() const { return m_ptr; } /// Return a C++ reference to the referenced object T& operator*() { return *m_ptr; } /// Return a const C++ reference to the referenced object const T& operator*() const { return *m_ptr; } /// Return a pointer to the referenced object operator T* () { return m_ptr; } /// Return a const pointer to the referenced object T* get() { return m_ptr; } /// Return a pointer to the referenced object const T* get() const { return m_ptr; } private: T *m_ptr; }; #endif /* __OBJECT_H */