Lunchbox  1.4.0
scopedMutex.h
00001 
00002 /* Copyright (c) 2006-2012, Stefan Eilemann <eile@equalizergraphics.com> 
00003  *
00004  * This library is free software; you can redistribute it and/or modify it under
00005  * the terms of the GNU Lesser General Public License version 2.1 as published
00006  * by the Free Software Foundation.
00007  *  
00008  * This library is distributed in the hope that it will be useful, but WITHOUT
00009  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
00010  * FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
00011  * details.
00012  * 
00013  * You should have received a copy of the GNU Lesser General Public License
00014  * along with this library; if not, write to the Free Software Foundation, Inc.,
00015  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
00016  */
00017 
00018 #ifndef LUNCHBOX_SCOPEDMUTEX_H
00019 #define LUNCHBOX_SCOPEDMUTEX_H
00020 
00021 #include <lunchbox/condition.h>   // used in inline method
00022 #include <lunchbox/lock.h>        // used in inline method
00023 #include <lunchbox/lockable.h>    // used in inline method
00024 #include <lunchbox/nonCopyable.h> // base class
00025 #include <lunchbox/types.h>
00026 
00027 namespace lunchbox
00028 {
00029     class WriteOp;
00030     class ReadOp;
00031 
00033     template< class L, class T > struct ScopedMutexLocker {};
00034     template< class L > struct ScopedMutexLocker< L, WriteOp >
00035     {
00036         static inline void set( L& lock ) { lock.set(); }
00037         static inline void unset( L& lock ) { lock.unset(); }
00038     };
00039     template< class L > struct ScopedMutexLocker< L, ReadOp >
00040     {
00041         static inline void set( L& lock ) { lock.setRead(); }
00042         static inline void unset( L& lock ) { lock.unsetRead(); }
00043     };
00044     template<> struct ScopedMutexLocker< Condition, WriteOp >
00045     {
00046         static inline void set( Condition& cond ) { cond.lock(); }
00047         static inline void unset( Condition& cond ) { cond.unlock(); }
00048     };
00058     template< class L = Lock, class T = WriteOp >
00059     class ScopedMutex : public NonCopyable
00060     {
00061         typedef ScopedMutexLocker< L, T > LockTraits;
00062 
00063     public:
00073         explicit ScopedMutex( L* lock ) : _lock( lock )
00074             { if( lock ) LockTraits::set( *lock ); }
00075 
00077         explicit ScopedMutex( L& lock ) : _lock( &lock )
00078             { LockTraits::set( lock ); }
00079 
00084         template< typename LB > ScopedMutex( LB& lockable )
00085                 : _lock( &lockable.lock ) { LockTraits::set( lockable.lock ); }
00086 
00088         ~ScopedMutex() { leave(); }
00089 
00091         void leave() { if( _lock ) LockTraits::unset( *_lock ); _lock = 0; }
00092 
00093     private:
00094         ScopedMutex();
00095         L* _lock;
00096     };
00097 
00099     typedef ScopedMutex< SpinLock, ReadOp > ScopedFastRead;
00100 
00102     typedef ScopedMutex< SpinLock, WriteOp > ScopedFastWrite;
00103 
00105     typedef ScopedMutex< Lock, ReadOp > ScopedRead;
00106 
00108     typedef ScopedMutex< Lock, WriteOp > ScopedWrite;
00109 
00111     typedef ScopedMutex< Condition, WriteOp > ScopedCondition;
00112 }
00113 #endif //LUNCHBOX_SCOPEDMUTEX_H