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) 2000-2006 Torus Knot Software Ltd 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 You may alternatively use this source under the terms of a specific version of 00025 the OGRE Unrestricted License provided you have obtained such a license from 00026 Torus Knot Software Ltd. 00027 ----------------------------------------------------------------------------- 00028 */ 00029 #ifndef __SharedPtr_H__ 00030 #define __SharedPtr_H__ 00031 00032 #include "OgrePrerequisites.h" 00033 00034 namespace Ogre { 00035 00048 template<class T> class SharedPtr { 00049 protected: 00050 T* pRep; 00051 unsigned int* pUseCount; 00052 public: 00053 OGRE_AUTO_SHARED_MUTEX // public to allow external locking 00058 SharedPtr() : pRep(0), pUseCount(0) 00059 { 00060 OGRE_SET_AUTO_SHARED_MUTEX_NULL 00061 } 00062 00063 template< class Y> 00064 explicit SharedPtr(Y* rep) : pRep(rep), pUseCount(new unsigned int(1)) 00065 { 00066 OGRE_SET_AUTO_SHARED_MUTEX_NULL 00067 OGRE_NEW_AUTO_SHARED_MUTEX 00068 } 00069 SharedPtr(const SharedPtr& r) 00070 : pRep(0), pUseCount(0) 00071 { 00072 // lock & copy other mutex pointer 00073 00074 OGRE_SET_AUTO_SHARED_MUTEX_NULL 00075 OGRE_MUTEX_CONDITIONAL(r.OGRE_AUTO_MUTEX_NAME) 00076 { 00077 OGRE_LOCK_MUTEX(*r.OGRE_AUTO_MUTEX_NAME) 00078 OGRE_COPY_AUTO_SHARED_MUTEX(r.OGRE_AUTO_MUTEX_NAME) 00079 pRep = r.pRep; 00080 pUseCount = r.pUseCount; 00081 // Handle zero pointer gracefully to manage STL containers 00082 if(pUseCount) 00083 { 00084 ++(*pUseCount); 00085 } 00086 } 00087 } 00088 SharedPtr& operator=(const SharedPtr& r) { 00089 if (pRep == r.pRep) 00090 return *this; 00091 // Swap current data into a local copy 00092 // this ensures we deal with rhs and this being dependent 00093 SharedPtr<T> tmp(r); 00094 swap(tmp); 00095 return *this; 00096 } 00097 00098 template< class Y> 00099 SharedPtr(const SharedPtr<Y>& r) 00100 : pRep(0), pUseCount(0) 00101 { 00102 // lock & copy other mutex pointer 00103 00104 OGRE_SET_AUTO_SHARED_MUTEX_NULL 00105 OGRE_MUTEX_CONDITIONAL(r.OGRE_AUTO_MUTEX_NAME) 00106 { 00107 OGRE_LOCK_MUTEX(*r.OGRE_AUTO_MUTEX_NAME) 00108 OGRE_COPY_AUTO_SHARED_MUTEX(r.OGRE_AUTO_MUTEX_NAME) 00109 pRep = r.getPointer(); 00110 pUseCount = r.useCountPointer(); 00111 // Handle zero pointer gracefully to manage STL containers 00112 if(pUseCount) 00113 { 00114 ++(*pUseCount); 00115 } 00116 } 00117 } 00118 template< class Y> 00119 SharedPtr& operator=(const SharedPtr<Y>& r) { 00120 if (pRep == r.pRep) 00121 return *this; 00122 // Swap current data into a local copy 00123 // this ensures we deal with rhs and this being dependent 00124 SharedPtr<T> tmp(r); 00125 swap(tmp); 00126 return *this; 00127 } 00128 virtual ~SharedPtr() { 00129 release(); 00130 } 00131 00132 00133 inline T& operator*() const { assert(pRep); return *pRep; } 00134 inline T* operator->() const { assert(pRep); return pRep; } 00135 inline T* get() const { return pRep; } 00136 00141 void bind(T* rep) { 00142 assert(!pRep && !pUseCount); 00143 OGRE_NEW_AUTO_SHARED_MUTEX 00144 OGRE_LOCK_AUTO_SHARED_MUTEX 00145 pUseCount = new unsigned int(1); 00146 pRep = rep; 00147 } 00148 00149 inline bool unique() const { OGRE_LOCK_AUTO_SHARED_MUTEX assert(pUseCount); return *pUseCount == 1; } 00150 inline unsigned int useCount() const { OGRE_LOCK_AUTO_SHARED_MUTEX assert(pUseCount); return *pUseCount; } 00151 inline unsigned int* useCountPointer() const { return pUseCount; } 00152 00153 inline T* getPointer() const { return pRep; } 00154 00155 inline bool isNull(void) const { return pRep == 0; } 00156 00157 inline void setNull(void) { 00158 if (pRep) 00159 { 00160 // can't scope lock mutex before release incase deleted 00161 release(); 00162 pRep = 0; 00163 pUseCount = 0; 00164 } 00165 } 00166 00167 protected: 00168 00169 inline void release(void) 00170 { 00171 bool destroyThis = false; 00172 00173 /* If the mutex is not initialized to a non-zero value, then 00174 neither is pUseCount nor pRep. 00175 */ 00176 00177 OGRE_MUTEX_CONDITIONAL(OGRE_AUTO_MUTEX_NAME) 00178 { 00179 // lock own mutex in limited scope (must unlock before destroy) 00180 OGRE_LOCK_AUTO_SHARED_MUTEX 00181 if (pUseCount) 00182 { 00183 if (--(*pUseCount) == 0) 00184 { 00185 destroyThis = true; 00186 } 00187 } 00188 } 00189 if (destroyThis) 00190 destroy(); 00191 00192 OGRE_SET_AUTO_SHARED_MUTEX_NULL 00193 } 00194 00195 virtual void destroy(void) 00196 { 00197 // IF YOU GET A CRASH HERE, YOU FORGOT TO FREE UP POINTERS 00198 // BEFORE SHUTTING OGRE DOWN 00199 // Use setNull() before shutdown or make sure your pointer goes 00200 // out of scope before OGRE shuts down to avoid this. 00201 delete pRep; 00202 delete pUseCount; 00203 OGRE_DELETE_AUTO_SHARED_MUTEX 00204 } 00205 00206 virtual void swap(SharedPtr<T> &other) 00207 { 00208 std::swap(pRep, other.pRep); 00209 std::swap(pUseCount, other.pUseCount); 00210 #if OGRE_THREAD_SUPPORT 00211 std::swap(OGRE_AUTO_MUTEX_NAME, other.OGRE_AUTO_MUTEX_NAME); 00212 #endif 00213 } 00214 }; 00215 00216 template<class T, class U> inline bool operator==(SharedPtr<T> const& a, SharedPtr<U> const& b) 00217 { 00218 return a.get() == b.get(); 00219 } 00220 00221 template<class T, class U> inline bool operator!=(SharedPtr<T> const& a, SharedPtr<U> const& b) 00222 { 00223 return a.get() != b.get(); 00224 } 00225 } 00226 00227 00228 00229 #endif
Copyright © 2000-2005 by The OGRE Team
This work is licensed under a Creative Commons Attribution-ShareAlike 2.5 License.
Last modified Sun Sep 30 10:50:57 2007