BufferLocked.hpp

/***************************************************************************
  tag: Peter Soetens  Wed Jan 18 14:11:39 CET 2006  BufferLocked.hpp

                        BufferLocked.hpp -  description
                           -------------------
    begin                : Wed January 18 2006
    copyright            : (C) 2006 Peter Soetens
    email                : peter.soetens@mech.kuleuven.be

 ***************************************************************************
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 *   version 2 of the License.                                             *
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 *   software library without restriction.  Specifically, if other files   *
 *   instantiate templates or use macros or inline functions from this     *
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 *   resulting executable to be covered by the GNU General Public          *
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#ifndef ORO_CORELIB_BUFFER_LOCKED_HPP
#define ORO_CORELIB_BUFFER_LOCKED_HPP

#include "os/Mutex.hpp"
#include "os/MutexLock.hpp"
#include "BufferInterface.hpp"
#include "BufferPolicy.hpp"
#include <deque>

namespace RTT
{

    template<class T, class ReadPolicy = NonBlockingPolicy, class WritePolicy = NonBlockingPolicy>
    class BufferLocked
        :public BufferInterface<T>
    {
    public:

        typedef typename ReadInterface<T>::reference_t reference_t;
        typedef typename WriteInterface<T>::param_t param_t;
        typedef typename BufferInterface<T>::size_type size_type;
        typedef T value_t;

        BufferLocked( size_type size, const T& initial_value = T() )
            : cap(size), buf(), write_policy(size), read_policy(0)
        {
            buf.resize(size, initial_value);
            buf.resize(0);
        }

        ~BufferLocked() {}

        bool Push( param_t item )
        {
            write_policy.pop();
            OS::MutexLock locker(lock);
            if (cap == (size_type)buf.size() ) {
                write_policy.push();
                return false;
            }
            buf.push_back( item );
            read_policy.push();
            return true;
        }

        size_type Push(const std::vector<T>& items)
        {
            write_policy.pop( items.size() );
            OS::MutexLock locker(lock);
            typename std::vector<T>::const_iterator itl( items.begin() );
            while ( ((size_type)buf.size() != cap) && (itl != items.end()) ) {
                buf.push_back( *itl );
                ++itl;
                read_policy.push();
            }
            write_policy.push( itl - items.begin() );
            return (itl - items.begin());

        }
        bool Pop( reference_t item )
        {
            read_policy.pop();
            OS::MutexLock locker(lock);
            if ( buf.empty() ) {
                read_policy.push();
                return false;
            }
            item = buf.front();
            buf.pop_front();
            write_policy.push();
            return true;
        }

        size_type Pop(std::vector<T>& items )
        {
            OS::MutexLock locker(lock);
            int quant = 0;
            while ( !buf.empty() ) {
                items.push_back( buf.front() );
                buf.pop_front();
                ++quant;
                read_policy.pop();
                write_policy.push();
            }
            return quant;
        }

        value_t front() const
        {
            OS::MutexLock locker(lock);
            value_t item = value_t();
            if ( !buf.empty() )
                item = buf.front();
            return item;
        }

        size_type capacity() const {
            OS::MutexLock locker(lock);
            return cap;
        }

        size_type size() const {
            OS::MutexLock locker(lock);
            return buf.size();
        }

        void clear() {
            OS::MutexLock locker(lock);
            buf.clear();
        }

        bool empty() const {
            OS::MutexLock locker(lock);
            return buf.empty();
        }

        bool full() const {
            OS::MutexLock locker(lock);
            return (size_type)buf.size() ==  cap;
        }
    private:
        size_type cap;
        std::deque<T> buf;
        mutable OS::Mutex lock;
        WritePolicy write_policy;
        ReadPolicy read_policy;
    };
}

#endif // BUFFERSIMPLE_HPP