Contiki 2.5
cooja_mt.c
1 /*
2  * Copyright (c) 2004, Swedish Institute of Computer Science.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  * notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  * notice, this list of conditions and the following disclaimer in the
12  * documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the Institute nor the names of its contributors
14  * may be used to endorse or promote products derived from this software
15  * without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * This file is part of the Contiki operating system.
30  *
31  * Author: Adam Dunkels <adam@sics.se>
32  *
33  * $Id: cooja_mt.c,v 1.2 2009/09/03 12:57:57 nvt-se Exp $
34  */
35 /*
36  * This file is ripped from mt.c of the Contiki Multi-threading library.
37  * Fredrik Osterlind <fros@sics.se>
38  */
39 
40 #include "contiki.h"
41 #include "sys/cooja_mt.h"
42 #include "sys/cc.h"
43 
44 #define MT_STATE_READY 1
45 #define MT_STATE_RUNNING 2
46 #define MT_STATE_EXITED 5
47 
48 static struct cooja_mt_thread *current;
49 
50 /*--------------------------------------------------------------------------*/
51 void
52 cooja_mt_init(void)
53 {
54  cooja_mtarch_init();
55 }
56 /*--------------------------------------------------------------------------*/
57 void
58 cooja_mt_remove(void)
59 {
60  cooja_mtarch_remove();
61 }
62 /*--------------------------------------------------------------------------*/
63 void
64 cooja_mt_start(struct cooja_mt_thread *thread, void (* function)(void *), void *data)
65 {
66  /* Call the architecture dependant function to set up the processor
67  stack with the correct parameters. */
68  cooja_mtarch_start(&thread->thread, function, data);
69 
70  thread->state = MT_STATE_READY;
71 }
72 /*--------------------------------------------------------------------------*/
73 void
74 cooja_mt_exec(struct cooja_mt_thread *thread)
75 {
76  if(thread->state == MT_STATE_READY) {
77  thread->state = MT_STATE_RUNNING;
78  current = thread;
79  /* Switch context to the thread. The function call will not return
80  until the the thread has yielded, or is preempted. */
81  cooja_mtarch_exec(&thread->thread);
82  }
83 }
84 /*--------------------------------------------------------------------------*/
85 void
86 cooja_mt_exit(void)
87 {
88  current->state = MT_STATE_EXITED;
89  current = NULL;
90  cooja_mtarch_yield();
91 }
92 /*--------------------------------------------------------------------------*/
93 void
94 cooja_mt_yield(void)
95 {
96  current->state = MT_STATE_READY;
97  current = NULL;
98  /* This function is called from the running thread, and we call the
99  switch function in order to switch the thread to the main Contiki
100  program instead. For us, the switch function will not return
101  until the next time we are scheduled to run. */
102  cooja_mtarch_yield();
103 }