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- /**
- * \addtogroup timer
- * @{
- */
-
- /**
- * \file
- * Timer library implementation.
- * \author
- * Adam Dunkels <[email protected]>
- */
-
- /*
- * Copyright (c) 2004, Swedish Institute of Computer Science.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the Institute nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- * This file is part of the uIP TCP/IP stack
- *
- * Author: Adam Dunkels <[email protected]>
- *
- * $Id: timer.c,v 1.2 2006/06/12 08:00:30 adam Exp $
- */
-
- #include "clock.h"
- #include "timer.h"
-
- /*---------------------------------------------------------------------------*/
- /**
- * Set a timer.
- *
- * This function is used to set a timer for a time sometime in the
- * future. The function timer_expired() will evaluate to true after
- * the timer has expired.
- *
- * \param t A pointer to the timer
- * \param interval The interval before the timer expires.
- *
- */
- void
- timer_set(struct timer *t, clock_time_t interval)
- {
- t->interval = interval;
- t->start = clock_time();
- }
- /*---------------------------------------------------------------------------*/
- /**
- * Reset the timer with the same interval.
- *
- * This function resets the timer with the same interval that was
- * given to the timer_set() function. The start point of the interval
- * is the exact time that the timer last expired. Therefore, this
- * function will cause the timer to be stable over time, unlike the
- * timer_restart() function.
- *
- * \param t A pointer to the timer.
- *
- * \sa timer_restart()
- */
- void
- timer_reset(struct timer *t)
- {
- t->start += t->interval;
- }
- /*---------------------------------------------------------------------------*/
- /**
- * Restart the timer from the current point in time
- *
- * This function restarts a timer with the same interval that was
- * given to the timer_set() function. The timer will start at the
- * current time.
- *
- * \note A periodic timer will drift if this function is used to reset
- * it. For periodic timers, use the timer_reset() function instead.
- *
- * \param t A pointer to the timer.
- *
- * \sa timer_reset()
- */
- void
- timer_restart(struct timer *t)
- {
- t->start = clock_time();
- }
- /*---------------------------------------------------------------------------*/
- /**
- * Check if a timer has expired.
- *
- * This function tests if a timer has expired and returns true or
- * false depending on its status.
- *
- * \param t A pointer to the timer
- *
- * \return Non-zero if the timer has expired, zero otherwise.
- *
- */
- int
- timer_expired(struct timer *t)
- {
- return (clock_time_t)(clock_time() - t->start) >= (clock_time_t)t->interval;
- }
- /*---------------------------------------------------------------------------*/
-
- /** @} */
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