Condition.hxx

Go to the documentation of this file.

/*
 * Copyright (c) 2004 MUSIC TECHNOLOGY GROUP (MTG)
 *                         UNIVERSITAT POMPEU FABRA
 *
 *
 * This program 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#ifndef __CONDITION__
#define __CONDITION__

#include "ErrSystem.hxx"
#include "Lock.hxx"
#include <pthread.h>

namespace CLAM
{

        struct xtime;

        class Condition
        {
        public:
                Condition();
                ~Condition();

                void NotifyOne();
                void NotifyAll();
                
                template <typename L>
                void Wait( L& lock )
                {
                        if ( !lock )
                                throw LockError("Invalid lock");
                        
                        DoWait( lock.mMutex );
                }

                template <typename L, typename Pr >
                void Wait( L& lock, Pr predicate )
                {
                        if ( !lock )
                                throw LockError("Invalid lock");

                        while ( !predicate() )
                                DoWait( lock.mMutex );
                }

                template <typename L>
                bool TimedWait( L& lock, const xtime& xt )
                {
                        if (!lock )
                                throw LockError();

                        return DoTimedWait( lock.mMutex, xt );
                }

                template <typename L, typename Pr>
                bool TimedWait( L& lock, const xtime& xt, Pr predicate )
                {
                        if ( !lock )
                                throw LockError();

                        while( !predicate() )
                                {
                                        if (!DoTimedWait( lock.mMutex, xt ) )
                                                return false;
                                }

                        return true;
                }

        private:
                
                template <typename M>
                void DoWait( M& mutex )
                {
                        typedef typename Hidden::LockOps<M> LockOps;
                        typename LockOps::LockState state;

                        LockOps::Unlock( mutex, state );
                        DoWait( state.pmutex );
                        LockOps::Lock( mutex, state );
                }

                template <typename M>
                bool DoTimedWait( M& mutex, const xtime& xt )
                {
                        typedef typename Hidden::LockOps<M> LockOps;
                        typename LockOps::LockState state;
                        
                        LockOps::Unlock( mutex, state );

                        bool ret = false;

                        ret = DoTimedWait( xt, state.pmutex );

                        LockOps::Lock( mutex, state );

                        return ret;
                }

                void DoWait( pthread_mutex_t* pMutex );

                bool DoTimedWait( const xtime& xt, pthread_mutex_t* pMutex);

                pthread_cond_t mCondition;
        };

} // end of namespace CLAM

#endif // Condition.hxx