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/*
* 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 uIP TCP/IP stack
*
* Author: Adam Dunkels <adam@sics.se>
*
* $Id: lc-addrlabels.h,v 1.3 2006/06/12 08:00:30 adam Exp $
*/
/**
* \addtogroup lc
* @{
*/
/**
* \file
* Implementation of local continuations based on the "Labels as
* values" feature of gcc
* \author
* Adam Dunkels <adam@sics.se>
*
* This implementation of local continuations is based on a special
* feature of the GCC C compiler called "labels as values". This
* feature allows assigning pointers with the address of the code
* corresponding to a particular C label.
*
* For more information, see the GCC documentation:
* http://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html
*
* Thanks to dividuum for finding the nice local scope label
* implementation.
*/
#ifndef __LC_ADDRLABELS_H__
#define __LC_ADDRLABELS_H__
/** \hideinitializer */
typedef void * lc_t;
#define LC_INIT(s) s = NULL
#define LC_RESUME(s) \
do { \
if(s != NULL) { \
goto *s; \
} \
} while(0)
#define LC_SET(s) \
do { ({ __label__ resume; resume: (s) = &&resume; }); }while(0)
#define LC_END(s)
#endif /* __LC_ADDRLABELS_H__ */
/** @} */