#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"
#include <pthread.h>
namespace stxxl
{
class state
{
pthread_mutex_t mutex;
pthread_cond_t cond;
int _state;
public:
state (int s = 0):_state (s)
{
stxxl_nassert (pthread_mutex_init (&mutex, NULL));
stxxl_nassert (pthread_cond_init (&cond, NULL));
};
~state ()
{
int res = pthread_mutex_trylock (&mutex);
if (res == 0 || res == EBUSY)
stxxl_nassert (pthread_mutex_unlock
(&mutex))
else
stxxl_function_error
stxxl_nassert (pthread_mutex_destroy
(&mutex));
stxxl_nassert (pthread_cond_destroy (&cond));
};
void set_to (int new_state)
{
stxxl_nassert (pthread_mutex_lock (&mutex));
_state = new_state;
stxxl_nassert (pthread_mutex_unlock (&mutex));
stxxl_nassert (pthread_cond_broadcast (&cond));
};
void wait_for (int needed_state)
{
stxxl_nassert (pthread_mutex_lock (&mutex));
while (needed_state != _state)
stxxl_nassert (pthread_cond_wait
(&cond, &mutex));
stxxl_nassert (pthread_mutex_unlock (&mutex));
};
int operator () ()
{
int res;
stxxl_nassert (pthread_mutex_lock (&mutex));
res = _state;
stxxl_nassert (pthread_mutex_unlock (&mutex));
return res;
};
};
}
#endif