/** \addtogroup sys * @{ */ /** * \defgroup timer Timer library * * The Contiki kernel does not provide support for timed * events. Rather, an application that wants to use timers needs to * explicitly use the timer library. * * The timer library provides functions for setting, resetting and * restarting timers, and for checking if a timer has expired. An * application must "manually" check if its timers have expired; this * is not done automatically. * * A timer is declared as a \c struct \c timer and all access to the * timer is made by a pointer to the declared timer. * * \note The timer library is not able to post events when a timer * expires. The \ref etimer "Event timers" should be used for this * purpose. * * \note The timer library uses the \ref clock "Clock library" to * measure time. Intervals should be specified in the format used by * the clock library. * * \sa \ref etimer "Event timers" * * @{ */ /** * \file * Timer library header file. * \author * Adam Dunkels <adam@sics.se> */ /* * 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 Contiki operating system. * * Author: Adam Dunkels <adam@sics.se> * * $Id: timer.h,v 1.2 2008/09/21 08:58:05 adamdunkels Exp $ */ #ifndef __TIMER_H__ #define __TIMER_H__ #include "sys/clock.h" /** * A timer. * * This structure is used for declaring a timer. The timer must be set * with timer_set() before it can be used. * * \hideinitializer */ struct timer { clock_time_t start; clock_time_t interval; }; void timer_set(struct timer *t, clock_time_t interval); void timer_reset(struct timer *t); void timer_restart(struct timer *t); int timer_expired(struct timer *t); clock_time_t timer_remaining(struct timer *t); #endif /* __TIMER_H__ */ /** @} */ /** @} */