00001 /* 00002 ----------------------------------------------------------------------------- 00003 This source file is part of OGRE 00004 (Object-oriented Graphics Rendering Engine) 00005 For the latest info, see http://www.ogre3d.org/ 00006 00007 Copyright (c) 2000-2005 The OGRE Team 00008 Also see acknowledgements in Readme.html 00009 00010 This program is free software; you can redistribute it and/or modify it under 00011 the terms of the GNU Lesser General Public License as published by the Free Software 00012 Foundation; either version 2 of the License, or (at your option) any later 00013 version. 00014 00015 This program is distributed in the hope that it will be useful, but WITHOUT 00016 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 00017 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. 00018 00019 You should have received a copy of the GNU Lesser General Public License along with 00020 this program; if not, write to the Free Software Foundation, Inc., 59 Temple 00021 Place - Suite 330, Boston, MA 02111-1307, USA, or go to 00022 http://www.gnu.org/copyleft/lesser.txt. 00023 ----------------------------------------------------------------------------- 00024 */ 00025 #ifndef __SharedPtr_H__ 00026 #define __SharedPtr_H__ 00027 00028 #include "OgrePrerequisites.h" 00029 00030 namespace Ogre { 00031 00044 template<class T> class SharedPtr { 00045 protected: 00046 T* pRep; 00047 unsigned int* pUseCount; 00048 public: 00049 OGRE_AUTO_SHARED_MUTEX // public to allow external locking 00054 SharedPtr() : pRep(0), pUseCount(0) 00055 { 00056 OGRE_SET_AUTO_SHARED_MUTEX_NULL 00057 } 00058 00059 explicit SharedPtr(T* rep) : pRep(rep), pUseCount(new unsigned int(1)) 00060 { 00061 OGRE_SET_AUTO_SHARED_MUTEX_NULL 00062 OGRE_NEW_AUTO_SHARED_MUTEX 00063 } 00064 SharedPtr(const SharedPtr& r) 00065 : pRep(0), pUseCount(0) 00066 { 00067 // lock & copy other mutex pointer 00068 00069 OGRE_SET_AUTO_SHARED_MUTEX_NULL 00070 OGRE_MUTEX_CONDITIONAL(r.OGRE_AUTO_MUTEX_NAME) 00071 { 00072 OGRE_LOCK_MUTEX(*r.OGRE_AUTO_MUTEX_NAME) 00073 OGRE_COPY_AUTO_SHARED_MUTEX(r.OGRE_AUTO_MUTEX_NAME) 00074 pRep = r.pRep; 00075 pUseCount = r.pUseCount; 00076 // Handle zero pointer gracefully to manage STL containers 00077 if(pUseCount) 00078 { 00079 ++(*pUseCount); 00080 } 00081 } 00082 } 00083 SharedPtr& operator=(const SharedPtr& r) { 00084 if (pRep == r.pRep) 00085 return *this; 00086 release(); 00087 // lock & copy other mutex pointer 00088 OGRE_MUTEX_CONDITIONAL(r.OGRE_AUTO_MUTEX_NAME) 00089 { 00090 OGRE_LOCK_MUTEX(*r.OGRE_AUTO_MUTEX_NAME) 00091 OGRE_COPY_AUTO_SHARED_MUTEX(r.OGRE_AUTO_MUTEX_NAME) 00092 pRep = r.pRep; 00093 pUseCount = r.pUseCount; 00094 if (pUseCount) 00095 { 00096 ++(*pUseCount); 00097 } 00098 } 00099 return *this; 00100 } 00101 virtual ~SharedPtr() { 00102 release(); 00103 } 00104 00105 00106 inline T& operator*() const { assert(pRep); return *pRep; } 00107 inline T* operator->() const { assert(pRep); return pRep; } 00108 inline T* get() const { return pRep; } 00109 00114 void bind(T* rep) { 00115 assert(!pRep && !pUseCount); 00116 OGRE_NEW_AUTO_SHARED_MUTEX 00117 OGRE_LOCK_AUTO_SHARED_MUTEX 00118 pUseCount = new unsigned int(1); 00119 pRep = rep; 00120 } 00121 00122 inline bool unique() const { OGRE_LOCK_AUTO_SHARED_MUTEX assert(pUseCount); return *pUseCount == 1; } 00123 inline unsigned int useCount() const { OGRE_LOCK_AUTO_SHARED_MUTEX assert(pUseCount); return *pUseCount; } 00124 inline unsigned int* useCountPointer() const { return pUseCount; } 00125 00126 inline T* getPointer() const { return pRep; } 00127 00128 inline bool isNull(void) const { return pRep == 0; } 00129 00130 inline void setNull(void) { 00131 if (pRep) 00132 { 00133 // can't scope lock mutex before release incase deleted 00134 release(); 00135 pRep = 0; 00136 pUseCount = 0; 00137 } 00138 } 00139 00140 protected: 00141 00142 inline void release(void) 00143 { 00144 bool destroyThis = false; 00145 00146 /* If the mutex is not initialized to a non-zero value, then 00147 neither is pUseCount nor pRep. 00148 */ 00149 00150 OGRE_MUTEX_CONDITIONAL(OGRE_AUTO_MUTEX_NAME) 00151 { 00152 // lock own mutex in limited scope (must unlock before destroy) 00153 OGRE_LOCK_AUTO_SHARED_MUTEX 00154 if (pUseCount) 00155 { 00156 if (--(*pUseCount) == 0) 00157 { 00158 destroyThis = true; 00159 } 00160 } 00161 } 00162 if (destroyThis) 00163 destroy(); 00164 00165 OGRE_SET_AUTO_SHARED_MUTEX_NULL 00166 } 00167 00168 virtual void destroy(void) 00169 { 00170 // IF YOU GET A CRASH HERE, YOU FORGOT TO FREE UP POINTERS 00171 // BEFORE SHUTTING OGRE DOWN 00172 // Use setNull() before shutdown or make sure your pointer goes 00173 // out of scope before OGRE shuts down to avoid this. 00174 delete pRep; 00175 delete pUseCount; 00176 OGRE_DELETE_AUTO_SHARED_MUTEX 00177 } 00178 }; 00179 00180 template<class T, class U> inline bool operator==(SharedPtr<T> const& a, SharedPtr<U> const& b) 00181 { 00182 return a.get() == b.get(); 00183 } 00184 00185 template<class T, class U> inline bool operator!=(SharedPtr<T> const& a, SharedPtr<U> const& b) 00186 { 00187 return a.get() != b.get(); 00188 } 00189 } 00190 00191 00192 00193 #endif
Copyright © 2000-2005 by The OGRE Team
This work is licensed under a Creative Commons Attribution-ShareAlike 2.5 License.
Last modified Sun Jul 23 10:05:41 2006