Ilya Krylov / UIPEthernet

123

uitility/uip_timer.c@0:5350a66d5279, 2014-09-15 (annotated)

Committer:
hudakz
Date:
Mon Sep 15 11:12:30 2014 +0000
Revision:
0:5350a66d5279
rev. 00

Who changed what in which revision?

UserRevisionLine numberNew contents of line
hudakz 0:5350a66d5279 1 /**
hudakz 0:5350a66d5279 2 * \addtogroup timer
hudakz 0:5350a66d5279 3 * @{
hudakz 0:5350a66d5279 4 */
hudakz 0:5350a66d5279 5 /**
hudakz 0:5350a66d5279 6 * \file
hudakz 0:5350a66d5279 7 * Timer library implementation.
hudakz 0:5350a66d5279 8 * \author
hudakz 0:5350a66d5279 9 * Adam Dunkels <adam@sics.se>
hudakz 0:5350a66d5279 10 */
hudakz 0:5350a66d5279 11 /*
hudakz 0:5350a66d5279 12 * Copyright (c) 2004, Swedish Institute of Computer Science.
hudakz 0:5350a66d5279 13 * All rights reserved.
hudakz 0:5350a66d5279 14 *
hudakz 0:5350a66d5279 15 * Redistribution and use in source and binary forms, with or without
hudakz 0:5350a66d5279 16 * modification, are permitted provided that the following conditions
hudakz 0:5350a66d5279 17 * are met:
hudakz 0:5350a66d5279 18 * 1. Redistributions of source code must retain the above copyright
hudakz 0:5350a66d5279 19 * notice, this list of conditions and the following disclaimer.
hudakz 0:5350a66d5279 20 * 2. Redistributions in binary form must reproduce the above copyright
hudakz 0:5350a66d5279 21 * notice, this list of conditions and the following disclaimer in the
hudakz 0:5350a66d5279 22 * documentation and/or other materials provided with the distribution.
hudakz 0:5350a66d5279 23 * 3. Neither the name of the Institute nor the names of its contributors
hudakz 0:5350a66d5279 24 * may be used to endorse or promote products derived from this software
hudakz 0:5350a66d5279 25 * without specific prior written permission.
hudakz 0:5350a66d5279 26 *
hudakz 0:5350a66d5279 27 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
hudakz 0:5350a66d5279 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
hudakz 0:5350a66d5279 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
hudakz 0:5350a66d5279 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
hudakz 0:5350a66d5279 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
hudakz 0:5350a66d5279 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
hudakz 0:5350a66d5279 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
hudakz 0:5350a66d5279 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
hudakz 0:5350a66d5279 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
hudakz 0:5350a66d5279 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
hudakz 0:5350a66d5279 37 * SUCH DAMAGE.
hudakz 0:5350a66d5279 38 *
hudakz 0:5350a66d5279 39 * This file is part of the uIP TCP/IP stack
hudakz 0:5350a66d5279 40 *
hudakz 0:5350a66d5279 41 * Author: Adam Dunkels <adam@sics.se>
hudakz 0:5350a66d5279 42 *
hudakz 0:5350a66d5279 43 * $Id: timer.c,v 1.2 2006/06/12 08:00:30 adam Exp $
hudakz 0:5350a66d5279 44 */
hudakz 0:5350a66d5279 45 #include "uip_clock.h"
hudakz 0:5350a66d5279 46 #include "uip_timer.h"
hudakz 0:5350a66d5279 47
hudakz 0:5350a66d5279 48 /*---------------------------------------------------------------------------*/
hudakz 0:5350a66d5279 49
hudakz 0:5350a66d5279 50 /**
hudakz 0:5350a66d5279 51 * Set a timer.
hudakz 0:5350a66d5279 52 *
hudakz 0:5350a66d5279 53 * This function is used to set a timer for a time sometime in the
hudakz 0:5350a66d5279 54 * future. The function timer_expired() will evaluate to true after
hudakz 0:5350a66d5279 55 * the timer has expired.
hudakz 0:5350a66d5279 56 *
hudakz 0:5350a66d5279 57 * \param t A pointer to the timer
hudakz 0:5350a66d5279 58 * \param interval The interval before the timer expires.
hudakz 0:5350a66d5279 59 *
hudakz 0:5350a66d5279 60 */
hudakz 0:5350a66d5279 61 void uip_timer_set(struct uip_timer* t, clock_time_t interval) {
hudakz 0:5350a66d5279 62 t->interval = interval;
hudakz 0:5350a66d5279 63 t->start = clock_time();
hudakz 0:5350a66d5279 64 }
hudakz 0:5350a66d5279 65
hudakz 0:5350a66d5279 66 /*---------------------------------------------------------------------------*/
hudakz 0:5350a66d5279 67
hudakz 0:5350a66d5279 68 /**
hudakz 0:5350a66d5279 69 * Reset the timer with the same interval.
hudakz 0:5350a66d5279 70 *
hudakz 0:5350a66d5279 71 * This function resets the timer with the same interval that was
hudakz 0:5350a66d5279 72 * given to the timer_set() function. The start point of the interval
hudakz 0:5350a66d5279 73 * is the exact time that the timer last expired. Therefore, this
hudakz 0:5350a66d5279 74 * function will cause the timer to be stable over time, unlike the
hudakz 0:5350a66d5279 75 * timer_rester() function.
hudakz 0:5350a66d5279 76 *
hudakz 0:5350a66d5279 77 * \param t A pointer to the timer.
hudakz 0:5350a66d5279 78 *
hudakz 0:5350a66d5279 79 * \sa timer_restart()
hudakz 0:5350a66d5279 80 */
hudakz 0:5350a66d5279 81 void uip_timer_reset(struct uip_timer* t) {
hudakz 0:5350a66d5279 82 t->start += t->interval;
hudakz 0:5350a66d5279 83 }
hudakz 0:5350a66d5279 84
hudakz 0:5350a66d5279 85 /*---------------------------------------------------------------------------*/
hudakz 0:5350a66d5279 86
hudakz 0:5350a66d5279 87 /**
hudakz 0:5350a66d5279 88 * Restart the timer from the current point in time
hudakz 0:5350a66d5279 89 *
hudakz 0:5350a66d5279 90 * This function restarts a timer with the same interval that was
hudakz 0:5350a66d5279 91 * given to the timer_set() function. The timer will start at the
hudakz 0:5350a66d5279 92 * current time.
hudakz 0:5350a66d5279 93 *
hudakz 0:5350a66d5279 94 * \note A periodic timer will drift if this function is used to reset
hudakz 0:5350a66d5279 95 * it. For preioric timers, use the timer_reset() function instead.
hudakz 0:5350a66d5279 96 *
hudakz 0:5350a66d5279 97 * \param t A pointer to the timer.
hudakz 0:5350a66d5279 98 *
hudakz 0:5350a66d5279 99 * \sa timer_reset()
hudakz 0:5350a66d5279 100 */
hudakz 0:5350a66d5279 101 void uip_timer_restart(struct uip_timer* t) {
hudakz 0:5350a66d5279 102 t->start = clock_time();
hudakz 0:5350a66d5279 103 }
hudakz 0:5350a66d5279 104
hudakz 0:5350a66d5279 105 /*---------------------------------------------------------------------------*/
hudakz 0:5350a66d5279 106
hudakz 0:5350a66d5279 107 /**
hudakz 0:5350a66d5279 108 * Check if a timer has expired.
hudakz 0:5350a66d5279 109 *
hudakz 0:5350a66d5279 110 * This function tests if a timer has expired and returns true or
hudakz 0:5350a66d5279 111 * false depending on its status.
hudakz 0:5350a66d5279 112 *
hudakz 0:5350a66d5279 113 * \param t A pointer to the timer
hudakz 0:5350a66d5279 114 *
hudakz 0:5350a66d5279 115 * \return Non-zero if the timer has expired, zero otherwise.
hudakz 0:5350a66d5279 116 *
hudakz 0:5350a66d5279 117 */
hudakz 0:5350a66d5279 118 int uip_timer_expired(struct uip_timer* t) {
hudakz 0:5350a66d5279 119 return(clock_time_t) (clock_time() - t->start) >= (clock_time_t) t->interval;
hudakz 0:5350a66d5279 120 }
hudakz 0:5350a66d5279 121
hudakz 0:5350a66d5279 122 /*---------------------------------------------------------------------------*/
hudakz 0:5350a66d5279 123 /** @} */