/* fiber.h - libtf fiber scheduler header
 *
 * Copyright (C) 2009 Timo Teräs <timo.teras@iki.fi>
 * All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 or later as
 * published by the Free Software Foundation.
 *
 * See http://www.gnu.org/ for details.
 */

#ifndef TF_FIBER_H
#define TF_FIBER_H

#include <errno.h>
#include <libtf/defines.h>
#include <libtf/atomic.h>
#include <libtf/list.h>
#include <libtf/heap.h>

#define TF_UCTX_H "uctx-setjmp.h"

/* Fiber wakeup reasons */
#define TF_WAKEUP_NONE		0
#define TF_WAKEUP_IMMEDIATE	EAGAIN
#define TF_WAKEUP_KILL		EINTR
#define TF_WAKEUP_TIMEOUT	ETIMEDOUT
#define TF_WAKEUP_FD		EIO

/* Scheduler */
struct tf_fiber;

struct tf_poll_data {
	int epoll_fd;
	int num_waiters;
};

struct tf_scheduler {
	struct tf_list_head	run_q;
	struct tf_heap_head	heap;
	struct tf_fiber *	active_fiber;
	int			num_fibers;
	tf_mtime_t		scheduler_time;
	struct tf_poll_data	poll_data;

};

static inline
struct tf_scheduler *tf_get_scheduler(void)
{
	extern struct tf_scheduler *__tf_scheduler;
	return __tf_scheduler;
}

static inline
struct tf_fiber *tf_get_fiber(void)
{
	return tf_get_scheduler()->active_fiber;
}

static inline
tf_mtime_t tf_mtime(void)
{
	return tf_get_scheduler()->scheduler_time;
}

/* Fiber creation */
typedef void (*tf_fiber_proc)(void *fiber);
int tf_main(tf_fiber_proc fiber_main);

void *tf_fiber_create(tf_fiber_proc fiber_main, int private_size);
void *tf_fiber_get(void *data);
void tf_fiber_put(void *data);

/* Scheduling and fiber management */
void tf_exit(void) attribute_noreturn;
void tf_kill(void *fiber);

int  tf_schedule(int wakeup_type);
int  tf_schedule_timeout(int milliseconds);
void tf_wakeup(struct tf_fiber *fiber, int wakeup_type);

int  tf_yield(void);
int  tf_msleep(int milliseconds);

#endif