diff options
Diffstat (limited to 'shared/loki/LockingPtr.h')
| -rw-r--r-- | shared/loki/LockingPtr.h | 156 |
1 files changed, 78 insertions, 78 deletions
diff --git a/shared/loki/LockingPtr.h b/shared/loki/LockingPtr.h index a50f5d6d..5482f075 100644 --- a/shared/loki/LockingPtr.h +++ b/shared/loki/LockingPtr.h @@ -7,12 +7,12 @@ // for You" by Alexandrescu, Andrei. // Published in the February 2001 issue of the C/C++ Users Journal. // http://www.cuj.com/documents/s=7998/cujcexp1902alexandr/ -// Permission to use, copy, modify, distribute and sell this software for any -// purpose is hereby granted without fee, provided that the above copyright -// notice appear in all copies and that both that copyright notice and this +// Permission to use, copy, modify, distribute and sell this software for any +// purpose is hereby granted without fee, provided that the above copyright +// notice appear in all copies and that both that copyright notice and this // permission notice appear in supporting documentation. -// The author makes no representations about the -// suitability of this software for any purpose. It is provided "as is" +// The author makes no representations about the +// suitability of this software for any purpose. It is provided "as is" // without express or implied warranty. // Prepared for Loki library by Richard Sposato //////////////////////////////////////////////////////////////////////////////// @@ -28,81 +28,81 @@ namespace Loki { - /** @class LockingPtr - Locks a volatile object and casts away volatility so that the object - can be safely used in a single-threaded region of code. - Original version of LockingPtr had only one template - for the shared - object, but not the mutex type. This version allows users to specify a - the mutex type as a LockingPolicy class. The only requirements for a - LockingPolicy class are to provide Lock and Unlock methods. +/** @class LockingPtr + Locks a volatile object and casts away volatility so that the object + can be safely used in a single-threaded region of code. + Original version of LockingPtr had only one template - for the shared + object, but not the mutex type. This version allows users to specify a + the mutex type as a LockingPolicy class. The only requirements for a + LockingPolicy class are to provide Lock and Unlock methods. + */ +template < typename SharedObject, typename LockingPolicy = LOKI_DEFAULT_MUTEX, + template<class> class ConstPolicy = LOKI_DEFAULT_CONSTNESS > +class LockingPtr +{ +public: + + typedef typename ConstPolicy<SharedObject>::Type ConstOrNotType; + + /** Constructor locks mutex associated with an object. + @param object Reference to object. + @param mutex Mutex used to control thread access to object. + */ + LockingPtr( volatile ConstOrNotType& object, LockingPolicy& mutex ) + : pObject_( const_cast< SharedObject* >( &object ) ), + pMutex_( &mutex ) + { + mutex.Lock(); + } + + typedef typename std::pair<volatile ConstOrNotType*, LockingPolicy*> Pair; + + /** Constructor locks mutex associated with an object. + @param lockpair a std::pair of pointers to the object and the mutex */ - template < typename SharedObject, typename LockingPolicy = LOKI_DEFAULT_MUTEX, - template<class> class ConstPolicy = LOKI_DEFAULT_CONSTNESS > - class LockingPtr + LockingPtr( Pair lockpair ) + : pObject_( const_cast< SharedObject* >( lockpair.first ) ), + pMutex_( lockpair.second ) + { + lockpair.second->Lock(); + } + + /// Destructor unlocks the mutex. + ~LockingPtr() + { + pMutex_->Unlock(); + } + + /// Star-operator dereferences pointer. + ConstOrNotType& operator * () + { + return *pObject_; + } + + /// Point-operator returns pointer to object. + ConstOrNotType* operator -> () { - public: - - typedef typename ConstPolicy<SharedObject>::Type ConstOrNotType; - - /** Constructor locks mutex associated with an object. - @param object Reference to object. - @param mutex Mutex used to control thread access to object. - */ - LockingPtr( volatile ConstOrNotType & object, LockingPolicy & mutex ) - : pObject_( const_cast< SharedObject * >( &object ) ), - pMutex_( &mutex ) - { - mutex.Lock(); - } - - typedef typename std::pair<volatile ConstOrNotType *, LockingPolicy *> Pair; - - /** Constructor locks mutex associated with an object. - @param lockpair a std::pair of pointers to the object and the mutex - */ - LockingPtr( Pair lockpair ) - : pObject_( const_cast< SharedObject * >( lockpair.first ) ), - pMutex_( lockpair.second ) - { - lockpair.second->Lock(); - } - - /// Destructor unlocks the mutex. - ~LockingPtr() - { - pMutex_->Unlock(); - } - - /// Star-operator dereferences pointer. - ConstOrNotType & operator * () - { - return *pObject_; - } - - /// Point-operator returns pointer to object. - ConstOrNotType * operator -> () - { - return pObject_; - } - - private: - - /// Default constructor is not implemented. - LockingPtr(); - - /// Copy-constructor is not implemented. - LockingPtr( const LockingPtr & ); - - /// Copy-assignment-operator is not implemented. - LockingPtr & operator = ( const LockingPtr & ); - - /// Pointer to the shared object. - ConstOrNotType * pObject_; - - /// Pointer to the mutex. - LockingPolicy * pMutex_; - - }; // end class LockingPtr + return pObject_; + } + +private: + + /// Default constructor is not implemented. + LockingPtr(); + + /// Copy-constructor is not implemented. + LockingPtr( const LockingPtr& ); + + /// Copy-assignment-operator is not implemented. + LockingPtr& operator = ( const LockingPtr& ); + + /// Pointer to the shared object. + ConstOrNotType* pObject_; + + /// Pointer to the mutex. + LockingPolicy* pMutex_; + +}; // end class LockingPtr } // namespace Loki |