yapf/countedptr.hpp
author KUDr
Sun, 31 Dec 2006 23:48:04 +0000
branchcustombridgeheads
changeset 5618 a7db50b9f817
parent 5094 f089c2bb68e9
permissions -rw-r--r--
(svn r7710) [cbh] - Fix: [YAPF] one more assert fixed. Call from the TrainController() added by (r7705) has broken YAPF because it was called when vehicle was already on the next tile (with cbh choice). Before it was always called before the train entered tile with choice.
/* $Id$ */

#ifndef COUNTEDPTR_HPP
#define COUNTEDPTR_HPP

#if 0 // reenable when needed
/** @file CCountedPtr - smart pointer implementation */

/** CCountedPtr - simple reference counting smart pointer.
 *
 *     One of the standard ways how to maintain object's lifetime.
 *
 *     See http://ootips.org/yonat/4dev/smart-pointers.html for more
 *   general info about smart pointers.
 *
 *     This class implements ref-counted pointer for objects/interfaces that
 *   support AddRef() and Release() methods.
 */
template <class Tcls_>
class CCountedPtr {
	/** redefine the template argument to make it visible for derived classes */
public:
	typedef Tcls_ Tcls;

protected:
	/** here we hold our pointer to the target */
	Tcls* m_pT;

public:
	/** default (NULL) construct or construct from a raw pointer */
	FORCEINLINE CCountedPtr(Tcls* pObj = NULL) : m_pT(pObj) {AddRef();};

	/** copy constructor (invoked also when initializing from another smart ptr) */
	FORCEINLINE CCountedPtr(const CCountedPtr& src) : m_pT(src.m_pT) {AddRef();};

	/** destructor releasing the reference */
	FORCEINLINE ~CCountedPtr() {Release();};

protected:
	/** add one ref to the underlaying object */
	FORCEINLINE void AddRef() {if (m_pT != NULL) m_pT->AddRef();}

public:
	/** release smart pointer (and decrement ref count) if not null */
	FORCEINLINE void Release() {if (m_pT != NULL) {m_pT->Release(); m_pT = NULL;}}

	/** dereference of smart pointer - const way */
	FORCEINLINE const Tcls* operator -> () const {assert(m_pT != NULL); return m_pT;};

	/** dereference of smart pointer - non const way */
	FORCEINLINE Tcls* operator -> () {assert(m_pT != NULL); return m_pT;};

	/** raw pointer casting operator - const way */
	FORCEINLINE operator const Tcls*() const {assert(m_pT == NULL); return m_pT;}

	/** raw pointer casting operator - non-const way */
	FORCEINLINE operator Tcls*() {assert(m_pT == NULL); return m_pT;}

	/** operator & to support output arguments */
	FORCEINLINE Tcls** operator &() {assert(m_pT == NULL); return &m_pT;}

	/** assignment operator from raw ptr */
	FORCEINLINE CCountedPtr& operator = (Tcls* pT) {Assign(pT); return *this;}

	/** assignment operator from another smart ptr */
	FORCEINLINE CCountedPtr& operator = (CCountedPtr& src) {Assign(src.m_pT); return *this;}

	/** assignment operator helper */
	FORCEINLINE void Assign(Tcls* pT);

	/** one way how to test for NULL value */
	FORCEINLINE bool IsNull() const {return m_pT == NULL;}

	/** another way how to test for NULL value */
	FORCEINLINE bool operator == (const CCountedPtr& sp) const {return m_pT == sp.m_pT;}

	/** yet another way how to test for NULL value */
	FORCEINLINE bool operator != (const CCountedPtr& sp) const {return m_pT != sp.m_pT;}

	/** assign pointer w/o incrementing ref count */
	FORCEINLINE void Attach(Tcls* pT) {Release(); m_pT = pT;}

	/** detach pointer w/o decrementing ref count */
	FORCEINLINE Tcls* Detach() {Tcls* pT = m_pT; m_pT = NULL; return pT;}
};

template <class Tcls_>
FORCEINLINE void CCountedPtr<Tcls_>::Assign(Tcls* pT)
{
	// if they are the same, we do nothing
	if (pT != m_pT) {
		if (pT) pT->AddRef();        // AddRef new pointer if any
		Tcls* pTold = m_pT;          // save original ptr
		m_pT = pT;                   // update m_pT to new value
		if (pTold) pTold->Release(); // release old ptr if any
	}
}

#endif /* 0 */
#endif /* COUNTEDPTR_HPP */