/* StarPU --- Runtime system for heterogeneous multicore architectures.
 *
 * Copyright (C) 2010  Université de Bordeaux 1
 * Copyright (C) 2010  Centre National de la Recherche Scientifique
 *
 * StarPU is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or (at
 * your option) any later version.
 *
 * StarPU is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * See the GNU Lesser General Public License in COPYING.LGPL for more details.
 */

#include <pthread.h>
#include <stdio.h>
#include <unistd.h>

#include <starpu.h>

#define NLOOPS	128

static void dummy_func(void *descr[] __attribute__ ((unused)), void *arg __attribute__ ((unused)))
{
}

static starpu_codelet dummy_codelet = 
{
	.where = STARPU_CPU|STARPU_CUDA,
	.cpu_func = dummy_func,
	.cuda_func = dummy_func,
	.model = NULL,
	.nbuffers = 0
};

static struct starpu_task *create_dummy_task(void)
{
	struct starpu_task *task = starpu_task_create();

	task->cl = &dummy_codelet;
	task->cl_arg = NULL;

	return task;
}

int main(int argc, char **argv)
{
	int ret;
	unsigned loop;

	starpu_init(NULL);

	struct starpu_task *taskA, *taskB;

	for (loop = 0; loop < NLOOPS; loop++)
	{
		taskA = create_dummy_task();
		taskB = create_dummy_task();

		/* By default, dynamically allocated tasks are destroyed at
		 * termination, we cannot declare a dependency on something
		 * that does not exist anymore. */
		taskA->destroy = 0;
		taskA->detach = 0;

		/* we wait for the tasks explicitly */
		taskB->detach = 0;

		ret = starpu_task_submit(taskA);
		STARPU_ASSERT(!ret);

		starpu_task_declare_deps_array(taskB, 1, &taskA);

		ret = starpu_task_submit(taskB);
		STARPU_ASSERT(!ret);

		ret = starpu_task_wait(taskB);
		STARPU_ASSERT(!ret);

		ret = starpu_task_wait(taskA);
		STARPU_ASSERT(!ret);
	}

	starpu_task_wait_for_all();

	starpu_shutdown();

	return 0;
}