EVE 1.0
lc-switch.h
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1 /*
2  * Copyright (c) 2004-2005, Swedish Institute of Computer Science.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
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9  * notice, this list of conditions and the following disclaimer.
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15  * without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
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28  *
29  * This file is part of the Contiki operating system.
30  *
31  * Author: Adam Dunkels <adam@sics.se>
32  *
33  */
34 
35 /**
36  * \addtogroup lc
37  * @{
38  */
39 
40 /**
41  * \file
42  * Implementation of local continuations based on switch() statement
43  * \author Adam Dunkels <adam@sics.se>
44  *
45  * This implementation of local continuations uses the C switch()
46  * statement to resume execution of a function somewhere inside the
47  * function's body. The implementation is based on the fact that
48  * switch() statements are able to jump directly into the bodies of
49  * control structures such as if() or while() statements.
50  *
51  * This implementation borrows heavily from Simon Tatham's coroutines
52  * implementation in C:
53  * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
54  */
55 
56 #ifndef LC_SWITCH_H_
57 #define LC_SWITCH_H_
58 
59 /* WARNING! lc implementation using switch() does not work if an
60  LC_SET() is done within another switch() statement! */
61 
62 /** \hideinitializer */
63 typedef unsigned short lc_t;
64 
65 #define LC_INIT(s) s = 0;
66 
67 #define LC_RESUME(s) switch(s) { case 0:
68 
69 #define LC_SET(s) s = __LINE__; case __LINE__:
70 
71 #define LC_END(s) }
72 
73 #endif /* LC_SWITCH_H_ */
74 
75 /** @} */
lc_t
void * lc_t
Definition: lc-addrlabels.h:63