xref: /nrf52832-nimble/rt-thread/components/net/uip/uip/lc-switch.h (revision 104654410c56c573564690304ae786df310c91fc)
1*10465441SEvalZero /*
2*10465441SEvalZero  * Copyright (c) 2004-2005, Swedish Institute of Computer Science.
3*10465441SEvalZero  * All rights reserved.
4*10465441SEvalZero  *
5*10465441SEvalZero  * Redistribution and use in source and binary forms, with or without
6*10465441SEvalZero  * modification, are permitted provided that the following conditions
7*10465441SEvalZero  * are met:
8*10465441SEvalZero  * 1. Redistributions of source code must retain the above copyright
9*10465441SEvalZero  *    notice, this list of conditions and the following disclaimer.
10*10465441SEvalZero  * 2. Redistributions in binary form must reproduce the above copyright
11*10465441SEvalZero  *    notice, this list of conditions and the following disclaimer in the
12*10465441SEvalZero  *    documentation and/or other materials provided with the distribution.
13*10465441SEvalZero  * 3. Neither the name of the Institute nor the names of its contributors
14*10465441SEvalZero  *    may be used to endorse or promote products derived from this software
15*10465441SEvalZero  *    without specific prior written permission.
16*10465441SEvalZero  *
17*10465441SEvalZero  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
18*10465441SEvalZero  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19*10465441SEvalZero  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20*10465441SEvalZero  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
21*10465441SEvalZero  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22*10465441SEvalZero  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23*10465441SEvalZero  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24*10465441SEvalZero  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25*10465441SEvalZero  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26*10465441SEvalZero  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27*10465441SEvalZero  * SUCH DAMAGE.
28*10465441SEvalZero  *
29*10465441SEvalZero  * This file is part of the uIP TCP/IP stack
30*10465441SEvalZero  *
31*10465441SEvalZero  * Author: Adam Dunkels <[email protected]>
32*10465441SEvalZero  *
33*10465441SEvalZero  * $Id: lc-switch.h,v 1.2 2006/06/12 08:00:30 adam Exp $
34*10465441SEvalZero  */
35*10465441SEvalZero 
36*10465441SEvalZero /**
37*10465441SEvalZero  * \addtogroup lc
38*10465441SEvalZero  * @{
39*10465441SEvalZero  */
40*10465441SEvalZero 
41*10465441SEvalZero /**
42*10465441SEvalZero  * \file
43*10465441SEvalZero  * Implementation of local continuations based on switch() statment
44*10465441SEvalZero  * \author Adam Dunkels <[email protected]>
45*10465441SEvalZero  *
46*10465441SEvalZero  * This implementation of local continuations uses the C switch()
47*10465441SEvalZero  * statement to resume execution of a function somewhere inside the
48*10465441SEvalZero  * function's body. The implementation is based on the fact that
49*10465441SEvalZero  * switch() statements are able to jump directly into the bodies of
50*10465441SEvalZero  * control structures such as if() or while() statmenets.
51*10465441SEvalZero  *
52*10465441SEvalZero  * This implementation borrows heavily from Simon Tatham's coroutines
53*10465441SEvalZero  * implementation in C:
54*10465441SEvalZero  * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
55*10465441SEvalZero  */
56*10465441SEvalZero 
57*10465441SEvalZero #ifndef __LC_SWITCH_H__
58*10465441SEvalZero #define __LC_SWTICH_H__
59*10465441SEvalZero 
60*10465441SEvalZero /* WARNING! lc implementation using switch() does not work if an
61*10465441SEvalZero    LC_SET() is done within another switch() statement! */
62*10465441SEvalZero 
63*10465441SEvalZero /** \hideinitializer */
64*10465441SEvalZero typedef unsigned short lc_t;
65*10465441SEvalZero 
66*10465441SEvalZero #define LC_INIT(s) s = 0;
67*10465441SEvalZero 
68*10465441SEvalZero #define LC_RESUME(s) switch(s) { case 0:
69*10465441SEvalZero 
70*10465441SEvalZero #define LC_SET(s) s = __LINE__; case __LINE__:
71*10465441SEvalZero 
72*10465441SEvalZero #define LC_END(s) }
73*10465441SEvalZero 
74*10465441SEvalZero #endif /* __LC_SWITCH_H__ */
75*10465441SEvalZero 
76*10465441SEvalZero /** @} */
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