contiki/core/sys/lc.h

/*
 * Copyright (c) 2004-2005, Swedish Institute of Computer Science.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the Institute nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * This file is part of the Contiki operating system.
 *
 * Author: Adam Dunkels <adam@sics.se>
 *
 */

/**
 * \addtogroup pt
 * @{
 */

/**
 * \defgroup lc Local continuations
 * @{
 *
 * Local continuations form the basis for implementing protothreads. A
 * local continuation can be <i>set</i> in a specific function to
 * capture the state of the function. After a local continuation has
 * been set can be <i>resumed</i> in order to restore the state of the
 * function at the point where the local continuation was set.
 *
 *
 */

/**
 * \file lc.h
 * Local continuations
 * \author
 * Adam Dunkels <adam@sics.se>
 *
 */

#ifdef DOXYGEN
/**
 * Initialize a local continuation.
 *
 * This operation initializes the local continuation, thereby
 * unsetting any previously set continuation state.
 *
 * \hideinitializer
 */
#define LC_INIT(lc)

/**
 * Set a local continuation.
 *
 * The set operation saves the state of the function at the point
 * where the operation is executed. As far as the set operation is
 * concerned, the state of the function does <b>not</b> include the
 * call-stack or local (automatic) variables, but only the program
 * counter and such CPU registers that needs to be saved.
 *
 * \hideinitializer
 */
#define LC_SET(lc)

/**
 * Resume a local continuation.
 *
 * The resume operation resumes a previously set local continuation, thus
 * restoring the state in which the function was when the local
 * continuation was set. If the local continuation has not been
 * previously set, the resume operation does nothing.
 *
 * \hideinitializer
 */
#define LC_RESUME(lc)

/**
 * Mark the end of local continuation usage.
 *
 * The end operation signifies that local continuations should not be
 * used any more in the function. This operation is not needed for
 * most implementations of local continuation, but is required by a
 * few implementations.
 *
 * \hideinitializer
 */
#define LC_END(lc)

/**
 * \var typedef lc_t;
 *
 * The local continuation type.
 *
 * \hideinitializer
 */
#endif /* DOXYGEN */

#ifndef __LC_H__
#define __LC_H__

#ifdef LC_CONF_INCLUDE
#include LC_CONF_INCLUDE
#else /* LC_CONF_INCLUDE */
#include "sys/lc-switch.h"
#endif /* LC_CONF_INCLUDE */

#endif /* __LC_H__ */

/** @} */
/** @} */