#ifndef BOOST_THREAD_BINARY_SEMAPHORE
#define BOOST_THREAD_BINARY_SEMAPHORE

#include <boost/thread/condition.hpp>
#include <boost/thread/mutex.hpp>

class binary_semaphore
{
    typedef boost::mutex::scoped_lock lock;

public:
    explicit binary_semaphore( bool initial_set = false )
    : _set( initial_set )
    {}

    void signal()
    {
        lock lk( _mutex );

        _set = true;

        _condition.notify_one();
    }

    void wait()
    {
        lock lk( _mutex );

        while( _set == false )
        {
             _condition.wait( lk );
        }

        _set = false ;
    }

private:

    bool _set;

    boost::mutex _mutex;

    boost::condition_variable _condition;
};


#endif // BOOST_THREAD_BINARY_SEMAPHORE