Contiki-NG
stimer.h
Go to the documentation of this file.
1 /*
2  * Copyright (c) 2004, 2008, 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>, Nicolas Tsiftes <nvt@sics.se>
32  *
33  */
34 
35 /**
36  * \file
37  * Second timer library header file.
38  * \author
39  * Adam Dunkels <adam@sics.se>, Nicolas Tsiftes <nvt@sics.se>
40  */
41 
42 /** \addtogroup timers
43  * @{ */
44 
45 /**
46  * \defgroup stimer Seconds timer library
47  *
48  * The stimer library provides functions for setting, resetting and
49  * restarting timers, and for checking if a timer has expired. An
50  * application must "manually" check if its timers have expired; this
51  * is not done automatically.
52  *
53  * A timer is declared as a \c struct \c stimer and all access to the
54  * timer is made by a pointer to the declared timer.
55  *
56  * \note The stimer library is not able to post events when a timer
57  * expires. The \ref etimer "Event timers" should be used for this
58  * purpose.
59  *
60  * \note The stimer library uses the \ref clock "Clock library" to
61  * measure time. Intervals should be specified in the seconds.
62  *
63  * \sa \ref etimer "Event timers"
64  *
65  * @{
66  */
67 
68 #ifndef STIMER_H_
69 #define STIMER_H_
70 
71 #include "sys/clock.h"
72 
73 /**
74  * A timer.
75  *
76  * This structure is used for declaring a timer. The timer must be set
77  * with stimer_set() before it can be used.
78  *
79  * \hideinitializer
80  */
81 struct stimer {
82  unsigned long start;
83  unsigned long interval;
84 };
85 
86 void stimer_set(struct stimer *t, unsigned long interval);
87 void stimer_reset(struct stimer *t);
88 void stimer_restart(struct stimer *t);
89 int stimer_expired(struct stimer *t);
90 unsigned long stimer_remaining(struct stimer *t);
91 unsigned long stimer_elapsed(struct stimer *t);
92 
93 
94 #endif /* STIMER_H_ */
95 
96 /** @} */
97 /** @} */
unsigned long stimer_remaining(struct stimer *t)
The time until the timer expires.
Definition: stimer.c:143
int stimer_expired(struct stimer *t)
Check if a timer has expired.
Definition: stimer.c:127
void stimer_restart(struct stimer *t)
Restart the timer from the current point in time.
Definition: stimer.c:110
unsigned long stimer_elapsed(struct stimer *t)
The time elapsed since the timer started.
Definition: stimer.c:159
void stimer_set(struct stimer *t, unsigned long interval)
Set a timer.
Definition: stimer.c:67
void stimer_reset(struct stimer *t)
Reset the timer with the same interval.
Definition: stimer.c:88
A timer.
Definition: stimer.h:81