cpu/native/rtimer-arch.c

   1 /*
   2  * Copyright (c) 2007, 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  * $Id: rtimer-arch.c,v 1.3 2008/02/09 14:02:12 oliverschmidt Exp $
  32  */
  33
  34 /**
  35  * \file
  36  *         Native (non-specific) code for the Contiki real-time module rt
  37  * \author
  38  *         Adam Dunkels <adam@sics.se>
  39  */
  40
  41 #include <signal.h>
  42 #include <sys/time.h>
  43 #include <stddef.h>
  44
  45 #include "sys/rtimer.h"
  46 #include "sys/clock.h"
  47
  48 #define DEBUG 0
  49 #if DEBUG
  50 #include <stdio.h>
  51 #define PRINTF(...) printf(__VA_ARGS__)
  52 #else
  53 #define PRINTF(...)
  54 #endif
  55
  56 /*---------------------------------------------------------------------------*/
  57 static void
  58 interrupt(int sig)
  59 {
  60   signal(sig, interrupt);
  61   rtimer_run_next();
  62 }
  63 /*---------------------------------------------------------------------------*/
  64 void
  65 rtimer_arch_init(void)
  66 {
  67   signal(SIGALRM, interrupt);
  68 }
  69 /*---------------------------------------------------------------------------*/
  70 void
  71 rtimer_arch_schedule(rtimer_clock_t t)
  72 {
  73   struct itimerval val;
  74   rtimer_clock_t c;
  75
  76   c = t - (unsigned short)clock_time();
  77
  78   val.it_value.tv_sec = c / 1000;
  79   val.it_value.tv_usec = (c % 1000) * 1000;
  80
  81   PRINTF("rtimer_arch_schedule time %u %u in %d.%d seconds\n", t, c, c / 1000,
  82          (c % 1000) * 1000);
  83
  84   val.it_interval.tv_sec = val.it_interval.tv_usec = 0;
  85   setitimer(ITIMER_REAL, &val, NULL);
  86 }
  87 /*---------------------------------------------------------------------------*/