00001 /* $Id: countedptr.hpp 24900 2013-01-08 22:46:42Z planetmaker $ */ 00002 00003 /* 00004 * This file is part of OpenTTD. 00005 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2. 00006 * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 00007 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>. 00008 */ 00009 00012 #ifndef COUNTEDPTR_HPP 00013 #define COUNTEDPTR_HPP 00014 00026 template <class Tcls_> 00027 class CCountedPtr { 00029 public: 00030 typedef Tcls_ Tcls; 00031 00032 protected: 00034 Tcls *m_pT; 00035 00036 public: 00038 inline CCountedPtr(Tcls *pObj = NULL) : m_pT(pObj) {AddRef();} 00039 00041 inline CCountedPtr(const CCountedPtr& src) : m_pT(src.m_pT) {AddRef();} 00042 00044 inline ~CCountedPtr() {Release();} 00045 00046 protected: 00048 inline void AddRef() {if (m_pT != NULL) m_pT->AddRef();} 00049 00050 public: 00052 inline void Release() {if (m_pT != NULL) {Tcls *pT = m_pT; m_pT = NULL; pT->Release();}} 00053 00055 inline const Tcls *operator -> () const {assert(m_pT != NULL); return m_pT;} 00056 00058 inline Tcls *operator -> () {assert(m_pT != NULL); return m_pT;} 00059 00061 inline operator const Tcls*() const {assert(m_pT == NULL); return m_pT;} 00062 00064 inline operator Tcls*() {return m_pT;} 00065 00067 inline Tcls** operator &() {assert(m_pT == NULL); return &m_pT;} 00068 00070 inline CCountedPtr& operator = (Tcls *pT) {Assign(pT); return *this;} 00071 00073 inline CCountedPtr& operator = (const CCountedPtr& src) {Assign(src.m_pT); return *this;} 00074 00076 inline void Assign(Tcls *pT); 00077 00079 inline bool IsNull() const {return m_pT == NULL;} 00080 00082 //inline bool operator == (const CCountedPtr& sp) const {return m_pT == sp.m_pT;} 00083 00085 //inline bool operator != (const CCountedPtr& sp) const {return m_pT != sp.m_pT;} 00086 00088 inline void Attach(Tcls *pT) {Release(); m_pT = pT;} 00089 00091 inline Tcls *Detach() {Tcls *pT = m_pT; m_pT = NULL; return pT;} 00092 }; 00093 00094 template <class Tcls_> 00095 inline void CCountedPtr<Tcls_>::Assign(Tcls *pT) 00096 { 00097 /* if they are the same, we do nothing */ 00098 if (pT != m_pT) { 00099 if (pT != NULL) pT->AddRef(); // AddRef new pointer if any 00100 Tcls *pTold = m_pT; // save original ptr 00101 m_pT = pT; // update m_pT to new value 00102 if (pTold != NULL) pTold->Release(); // release old ptr if any 00103 } 00104 } 00105 00111 template <class T> struct AdaptT { 00112 T m_t; 00113 00115 AdaptT(const T &t) 00116 : m_t(t) 00117 {} 00118 00120 T& operator = (const T &t) 00121 { 00122 m_t = t; 00123 return t; 00124 } 00125 00127 operator T& () 00128 { 00129 return m_t; 00130 } 00131 00133 operator const T& () const 00134 { 00135 return m_t; 00136 } 00137 }; 00138 00139 00149 struct SimpleCountedObject { 00150 int32 m_ref_cnt; 00151 00152 SimpleCountedObject() 00153 : m_ref_cnt(0) 00154 {} 00155 00156 virtual ~SimpleCountedObject() 00157 {} 00158 00159 virtual int32 AddRef(); 00160 virtual int32 Release(); 00161 virtual void FinalRelease() {}; 00162 }; 00163 00164 00165 00166 00167 #endif /* COUNTEDPTR_HPP */