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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-switch.h,v 1.2 2006/06/12 08:00:30 adam Exp $
*/
/**
* \addtogroup lc
* @{
*/
/**
* \file
* Implementation of local continuations based on switch() statment
* \author Adam Dunkels <adam@sics.se>
*
* This implementation of local continuations uses the C switch()
* statement to resume execution of a function somewhere inside the
* function's body. The implementation is based on the fact that
* switch() statements are able to jump directly into the bodies of
* control structures such as if() or while() statmenets.
*
* This implementation borrows heavily from Simon Tatham's coroutines
* implementation in C:
* http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
*/
#ifndef __LC_SWITCH_H__
#define __LC_SWTICH_H__
/* WARNING! lc implementation using switch() does not work if an
LC_SET() is done within another switch() statement! */
/** \hideinitializer */
typedef unsigned short lc_t;
#define LC_INIT(s) s = 0;
#define LC_RESUME(s) switch(s) { case 0:
#define LC_SET(s) s = __LINE__; case __LINE__:
#define LC_END(s) }
#endif /* __LC_SWITCH_H__ */
/** @} */
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