#ifndef STATE_HEADER
#define STATE_HEADER
/***************************************************************************
* state.h
*
* Sat Aug 24 23:53:53 2002
* Copyright 2002 Roman Dementiev
* dementiev@mpi-sb.mpg.de
****************************************************************************/
#include "utils.h"
#ifdef STXXL_BOOST_THREADS
#include <boost/thread/mutex.hpp>
#include <boost/thread/condition.hpp>
#else
#include <pthread.h>
#endif
namespace stxxl
{
class state
{
#ifdef STXXL_BOOST_THREADS
boost::mutex mutex;
boost::condition cond;
#else
pthread_mutex_t mutex;
pthread_cond_t cond;
#endif
int _state;
state(const state &); // forbidden
state & operator = (const state &); // forbidden
public:
state (int s = 0):_state (s)
{
#ifndef STXXL_BOOST_THREADS
stxxl_nassert (pthread_mutex_init (&mutex, NULL),resource_error);
stxxl_nassert (pthread_cond_init (&cond, NULL),resource_error);
#endif
};
~state ()
{
#ifndef STXXL_BOOST_THREADS
int res = pthread_mutex_trylock (&mutex);
if (res == 0 || res == EBUSY)
stxxl_nassert (pthread_mutex_unlock
(&mutex),resource_error)
else
stxxl_function_error(resource_error)
stxxl_nassert (pthread_mutex_destroy
(&mutex),resource_error);
stxxl_nassert (pthread_cond_destroy (&cond),resource_error);
#endif
};
void set_to (int new_state)
{
#ifdef STXXL_BOOST_THREADS
boost::mutex::scoped_lock Lock(mutex);
_state = new_state;
Lock.unlock();
cond.notify_all();
#else
stxxl_nassert (pthread_mutex_lock (&mutex),resource_error);
_state = new_state;
stxxl_nassert (pthread_mutex_unlock (&mutex),resource_error);
stxxl_nassert (pthread_cond_broadcast (&cond),resource_error);
#endif
};
void wait_for (int needed_state)
{
#ifdef STXXL_BOOST_THREADS
boost::mutex::scoped_lock Lock(mutex);
while (needed_state != _state)
cond.wait(Lock);
#else
stxxl_nassert (pthread_mutex_lock (&mutex),resource_error);
while (needed_state != _state)
stxxl_nassert (pthread_cond_wait
(&cond, &mutex),resource_error);
stxxl_nassert (pthread_mutex_unlock (&mutex),resource_error);
#endif
};
int operator () ()
{
#ifdef STXXL_BOOST_THREADS
boost::mutex::scoped_lock Lock(mutex);
return _state;
#else
int res;
stxxl_nassert (pthread_mutex_lock (&mutex),resource_error);
res = _state;
stxxl_nassert (pthread_mutex_unlock (&mutex),resource_error);
return res;
#endif
};
};
}
#endif