1 /* $NetBSD: timer.c,v 1.12 2015/06/05 14:09:20 roy Exp $ */ 2 /* $KAME: timer.c,v 1.11 2005/04/14 06:22:35 suz Exp $ */ 3 4 /* 5 * Copyright (C) 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <sys/queue.h> 34 #include <sys/time.h> 35 36 #include <limits.h> 37 #include <unistd.h> 38 #include <syslog.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <search.h> 42 #include "timer.h" 43 44 struct rtadvd_timer_head_t ra_timer = TAILQ_HEAD_INITIALIZER(ra_timer); 45 static struct timespec tm_limit = { LONG_MAX, 1000000000L - 1 }; 46 static struct timespec tm_max; 47 48 void 49 rtadvd_timer_init(void) 50 { 51 52 TAILQ_INIT(&ra_timer); 53 tm_max = tm_limit; 54 } 55 56 struct rtadvd_timer * 57 rtadvd_add_timer(struct rtadvd_timer *(*timeout) (void *), 58 void (*update) (void *, struct timespec *), 59 void *timeodata, void *updatedata) 60 { 61 struct rtadvd_timer *newtimer; 62 63 if ((newtimer = malloc(sizeof(*newtimer))) == NULL) { 64 syslog(LOG_ERR, 65 "<%s> can't allocate memory", __func__); 66 exit(1); 67 } 68 69 memset(newtimer, 0, sizeof(*newtimer)); 70 71 if (timeout == NULL) { 72 syslog(LOG_ERR, 73 "<%s> timeout function unspecified", __func__); 74 exit(1); 75 } 76 newtimer->expire = timeout; 77 newtimer->update = update; 78 newtimer->expire_data = timeodata; 79 newtimer->update_data = updatedata; 80 newtimer->tm = tm_max; 81 82 /* link into chain */ 83 TAILQ_INSERT_TAIL(&ra_timer, newtimer, next); 84 85 return(newtimer); 86 } 87 88 void 89 rtadvd_remove_timer(struct rtadvd_timer **timer) 90 { 91 92 if (*timer) { 93 TAILQ_REMOVE(&ra_timer, *timer, next); 94 free(*timer); 95 *timer = NULL; 96 } 97 } 98 99 void 100 rtadvd_set_timer(struct timespec *tm, struct rtadvd_timer *timer) 101 { 102 struct timespec now; 103 104 /* reset the timer */ 105 clock_gettime(CLOCK_MONOTONIC, &now); 106 timespecadd(&now, tm, &timer->tm); 107 108 /* upate the next expiration time */ 109 if (timespeccmp(&timer->tm, &tm_max, <)) 110 tm_max = timer->tm; 111 } 112 113 /* 114 * Check expiration for each timer. If a timer expires, 115 * call the expire function for the timer and update the timer. 116 * Return the next interval for select() call. 117 */ 118 struct timespec * 119 rtadvd_check_timer(void) 120 { 121 static struct timespec returnval; 122 struct timespec now; 123 struct rtadvd_timer *tm, *tmn; 124 125 clock_gettime(CLOCK_MONOTONIC, &now); 126 tm_max = tm_limit; 127 128 TAILQ_FOREACH_SAFE(tm, &ra_timer, next, tmn) { 129 if (timespeccmp(&tm->tm, &now, <=)) { 130 if ((*tm->expire)(tm->expire_data) == NULL) 131 continue; /* the timer was removed */ 132 if (tm->update) 133 (*tm->update)(tm->update_data, &tm->tm); 134 timespecadd(&tm->tm, &now, &tm->tm); 135 } 136 if (timespeccmp(&tm->tm, &tm_max, <)) 137 tm_max = tm->tm; 138 } 139 140 if (timespeccmp(&tm_max, &tm_limit, ==)) 141 return(NULL); 142 if (timespeccmp(&tm_max, &now, <)) { 143 /* this may occur when the interval is too small */ 144 timespecclear(&returnval); 145 } else 146 timespecsub(&tm_max, &now, &returnval); 147 return(&returnval); 148 } 149 150 struct timespec * 151 rtadvd_timer_rest(struct rtadvd_timer *timer) 152 { 153 static struct timespec returnval; 154 struct timespec now; 155 156 clock_gettime(CLOCK_MONOTONIC, &now); 157 if (timespeccmp(&timer->tm, &now, <=)) { 158 syslog(LOG_DEBUG, 159 "<%s> a timer must be expired, but not yet", 160 __func__); 161 returnval.tv_sec = 0; 162 returnval.tv_nsec = 0; 163 } 164 else 165 timespecsub(&timer->tm, &now, &returnval); 166 167 return(&returnval); 168 } 169