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/**************************************************************************\
*
* This file is part of the Coin 3D visualization library.
* Copyright (C) by Kongsberg Oil & Gas Technologies.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* ("GPL") version 2 as published by the Free Software Foundation.
* See the file LICENSE.GPL at the root directory of this source
* distribution for additional information about the GNU GPL.
*
* For using Coin with software that can not be combined with the GNU
* GPL, and for taking advantage of the additional benefits of our
* support services, please contact Kongsberg Oil & Gas Technologies
* about acquiring a Coin Professional Edition License.
*
* See http://www.coin3d.org/ for more information.
*
* Kongsberg Oil & Gas Technologies, Bygdoy Alle 5, 0257 Oslo, NORWAY.
* http://www.sim.no/ sales@sim.no coin-support@coin3d.org
*
\**************************************************************************/
#include <Inventor/C/threads/barrier.h>
#include <stdlib.h>
#include <stdio.h>
#include <assert.h>
#include <Inventor/C/threads/mutex.h>
#include <Inventor/C/threads/condvar.h>
#include "threads/barrierp.h"
/* ********************************************************************** */
/*
*/
cc_barrier *
cc_barrier_construct(unsigned int count)
{
cc_barrier * barrier;
barrier = (cc_barrier *) malloc(sizeof(cc_barrier));
barrier->numthreads = count;
barrier->counter = 0;
barrier->mutex = cc_mutex_construct();
barrier->condvar = cc_condvar_construct();
return barrier;
}
/*
*/
void
cc_barrier_destruct(cc_barrier * barrier)
{
assert(barrier != NULL);
cc_condvar_wake_all(barrier->condvar);
cc_condvar_destruct(barrier->condvar);
cc_mutex_destruct(barrier->mutex);
free(barrier);
}
/*
*/
int
cc_barrier_enter(cc_barrier * barrier)
{
assert(barrier != NULL);
cc_mutex_lock(barrier->mutex);
barrier->counter++;
if (barrier->counter == barrier->numthreads) {
barrier->counter = 0;
cc_condvar_wake_all(barrier->condvar);
cc_mutex_unlock(barrier->mutex);
return 1;
}
else {
cc_condvar_wait(barrier->condvar, barrier->mutex);
cc_mutex_unlock(barrier->mutex);
}
return 0;
}
/* ********************************************************************** */
/*!
\class SbBarrier Inventor/threads/SbBarrier.h
\brief The SbBarrier class implements the "barrier" multi-thread
synchronization technique.
\ingroup threads
A barrier is a synchronization mechanism that is used for blocking
threads as they enter the barrier until a given number of threads are
blocked, at which point all the threads are released again.
*/
/*!
\fn SbBarrier::SbBarrier(unsigned int count)
Constructor. The SbBarrier will be set for \c count number of
threads.
*/
/*!
\fn SbBarrier::~SbBarrier(void)
Destructor.
*/
/*!
\fn int SbBarrier::enter(void)
This method blocks the calling thread on this barrier. It returns
when the given number of threads have been blocked. 1 is
returned if the caller was the last thread to enter the barrier,
0 otherwise.
*/
/* ********************************************************************** */
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