KUDr@3900: /* $Id$ */
KUDr@3900: 
belugas@6977: /** @file countedptr.hpp */
belugas@6977: 
KUDr@3900: #ifndef COUNTEDPTR_HPP
KUDr@3900: #define COUNTEDPTR_HPP
KUDr@3900: 
KUDr@3900: /** @file CCountedPtr - smart pointer implementation */
KUDr@3900: 
KUDr@3900: /** CCountedPtr - simple reference counting smart pointer.
rubidium@4549:  *
rubidium@4549:  *     One of the standard ways how to maintain object's lifetime.
rubidium@4549:  *
rubidium@4549:  *     See http://ootips.org/yonat/4dev/smart-pointers.html for more
rubidium@4549:  *   general info about smart pointers.
rubidium@4549:  *
rubidium@4549:  *     This class implements ref-counted pointer for objects/interfaces that
rubidium@4549:  *   support AddRef() and Release() methods.
rubidium@4549:  */
KUDr@3900: template <class Tcls_>
KUDr@3900: class CCountedPtr {
KUDr@3900: 	/** redefine the template argument to make it visible for derived classes */
KUDr@3900: public:
KUDr@3900: 	typedef Tcls_ Tcls;
KUDr@3900: 
KUDr@3900: protected:
KUDr@3900: 	/** here we hold our pointer to the target */
KUDr@3900: 	Tcls* m_pT;
KUDr@3900: 
KUDr@3900: public:
KUDr@3900: 	/** default (NULL) construct or construct from a raw pointer */
KUDr@3900: 	FORCEINLINE CCountedPtr(Tcls* pObj = NULL) : m_pT(pObj) {AddRef();};
KUDr@3900: 
KUDr@3900: 	/** copy constructor (invoked also when initializing from another smart ptr) */
KUDr@3900: 	FORCEINLINE CCountedPtr(const CCountedPtr& src) : m_pT(src.m_pT) {AddRef();};
KUDr@3900: 
KUDr@3900: 	/** destructor releasing the reference */
KUDr@3900: 	FORCEINLINE ~CCountedPtr() {Release();};
KUDr@3900: 
KUDr@3900: protected:
KUDr@3900: 	/** add one ref to the underlaying object */
KUDr@3900: 	FORCEINLINE void AddRef() {if (m_pT != NULL) m_pT->AddRef();}
KUDr@3900: 
KUDr@3900: public:
KUDr@3900: 	/** release smart pointer (and decrement ref count) if not null */
rubidium@7792: 	FORCEINLINE void Release() {if (m_pT != NULL) {Tcls* pT = m_pT; m_pT = NULL; pT->Release();}}
KUDr@3900: 
KUDr@3900: 	/** dereference of smart pointer - const way */
KUDr@3900: 	FORCEINLINE const Tcls* operator -> () const {assert(m_pT != NULL); return m_pT;};
KUDr@3900: 
KUDr@3900: 	/** dereference of smart pointer - non const way */
KUDr@3900: 	FORCEINLINE Tcls* operator -> () {assert(m_pT != NULL); return m_pT;};
KUDr@3900: 
KUDr@3900: 	/** raw pointer casting operator - const way */
KUDr@3900: 	FORCEINLINE operator const Tcls*() const {assert(m_pT == NULL); return m_pT;}
KUDr@3900: 
KUDr@3900: 	/** raw pointer casting operator - non-const way */
rubidium@7792: 	FORCEINLINE operator Tcls*() {return m_pT;}
KUDr@3900: 
KUDr@3900: 	/** operator & to support output arguments */
KUDr@3900: 	FORCEINLINE Tcls** operator &() {assert(m_pT == NULL); return &m_pT;}
KUDr@3900: 
KUDr@3900: 	/** assignment operator from raw ptr */
KUDr@3900: 	FORCEINLINE CCountedPtr& operator = (Tcls* pT) {Assign(pT); return *this;}
KUDr@3900: 
KUDr@3900: 	/** assignment operator from another smart ptr */
rubidium@7792: 	FORCEINLINE CCountedPtr& operator = (const CCountedPtr& src) {Assign(src.m_pT); return *this;}
KUDr@3900: 
KUDr@3900: 	/** assignment operator helper */
KUDr@3900: 	FORCEINLINE void Assign(Tcls* pT);
KUDr@3900: 
KUDr@3900: 	/** one way how to test for NULL value */
KUDr@3900: 	FORCEINLINE bool IsNull() const {return m_pT == NULL;}
KUDr@3900: 
KUDr@3900: 	/** another way how to test for NULL value */
rubidium@7792: 	//FORCEINLINE bool operator == (const CCountedPtr& sp) const {return m_pT == sp.m_pT;}
KUDr@3900: 
KUDr@3900: 	/** yet another way how to test for NULL value */
rubidium@7792: 	//FORCEINLINE bool operator != (const CCountedPtr& sp) const {return m_pT != sp.m_pT;}
KUDr@3900: 
KUDr@3900: 	/** assign pointer w/o incrementing ref count */
KUDr@3900: 	FORCEINLINE void Attach(Tcls* pT) {Release(); m_pT = pT;}
KUDr@3900: 
KUDr@3900: 	/** detach pointer w/o decrementing ref count */
KUDr@3900: 	FORCEINLINE Tcls* Detach() {Tcls* pT = m_pT; m_pT = NULL; return pT;}
KUDr@3900: };
KUDr@3900: 
KUDr@3900: template <class Tcls_>
KUDr@3900: FORCEINLINE void CCountedPtr<Tcls_>::Assign(Tcls* pT)
KUDr@3900: {
KUDr@3900: 	// if they are the same, we do nothing
KUDr@3900: 	if (pT != m_pT) {
KUDr@3900: 		if (pT) pT->AddRef();        // AddRef new pointer if any
KUDr@3900: 		Tcls* pTold = m_pT;          // save original ptr
KUDr@3900: 		m_pT = pT;                   // update m_pT to new value
KUDr@3900: 		if (pTold) pTold->Release(); // release old ptr if any
KUDr@3900: 	}
KUDr@3900: }
KUDr@3900: 
rubidium@7792: /**
rubidium@7792:  * Adapter wrapper for CCountedPtr like classes that can't be used directly by stl
rubidium@7792:  * collections as item type. For example CCountedPtr has overloaded operator & which
rubidium@7792:  * prevents using CCountedPtr in stl collections (i.e. std::list<CCountedPtr<MyType> >)
rubidium@7792:  */
rubidium@7792: template <class T> struct AdaptT {
rubidium@7792: 	T m_t;
rubidium@7792: 
rubidium@7792: 	/** construct by wrapping the given object */
rubidium@7792: 	AdaptT(const T &t)
rubidium@7792: 		: m_t(t)
rubidium@7792: 	{}
rubidium@7792: 
rubidium@7792: 	/** assignment operator */
rubidium@7792: 	T& operator = (const T &t)
rubidium@7792: 	{
rubidium@7792: 		m_t = t;
rubidium@7792: 		return t;
rubidium@7792: 	}
rubidium@7792: 
rubidium@7792: 	/** type-cast operator (used when AdaptT is used instead of T) */
rubidium@7792: 	operator T& ()
rubidium@7792: 	{
rubidium@7792: 		return m_t;
rubidium@7792: 	}
rubidium@7792: 
rubidium@7792: 	/** const type-cast operator (used when AdaptT is used instead of const T) */
rubidium@7792: 	operator const T& () const
rubidium@7792: 	{
rubidium@7792: 		return m_t;
rubidium@7792: 	}
rubidium@7792: };
rubidium@7792: 
rubidium@7792: 
rubidium@7792: /** Simple counted object. Use it as base of your struct/class if you want to use
rubidium@7792:  *  basic reference counting. Your struct/class will destroy and free itself when
rubidium@7792:  *  last reference to it is released (using Relese() method). The initial reference
rubidium@7792:  *  count (when it is created) is zero (don't forget AddRef() at least one time if
rubidium@7792:  *  not using CCountedPtr<T>.
rubidium@7792:  *
rubidium@7792:  *  @see misc/countedobj.cpp for implementation.
rubidium@7792:  */
rubidium@7792: struct SimpleCountedObject {
rubidium@7792: 	int32 m_ref_cnt;
rubidium@7792: 
rubidium@7792: 	SimpleCountedObject()
rubidium@7792: 		: m_ref_cnt(0)
rubidium@7792: 	{}
rubidium@7792: 
rubidium@7792: 	virtual ~SimpleCountedObject()
rubidium@7792: 	{};
rubidium@7792: 
rubidium@7792: 	virtual int32 AddRef();
rubidium@7792: 	virtual int32 Release();
rubidium@7792: 	virtual void FinalRelease() {};
rubidium@7792: };
rubidium@7792: 
rubidium@7792: 
rubidium@7792: 
rubidium@7792: 
KUDr@3900: #endif /* COUNTEDPTR_HPP */