1 /* $NetBSD: timer.c,v 1.14 2017/11/06 15:15:04 christos 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 #include "logit.h" 44 #include "prog_ops.h" 45 46 struct rtadvd_timer_head_t ra_timer = TAILQ_HEAD_INITIALIZER(ra_timer); 47 static struct timespec tm_limit = { LONG_MAX, 1000000000L - 1 }; 48 static struct timespec tm_max; 49 50 void 51 rtadvd_timer_init(void) 52 { 53 54 TAILQ_INIT(&ra_timer); 55 tm_max = tm_limit; 56 } 57 58 struct rtadvd_timer * 59 rtadvd_add_timer(struct rtadvd_timer *(*timeout) (void *), 60 void (*update) (void *, struct timespec *), 61 void *timeodata, void *updatedata) 62 { 63 struct rtadvd_timer *newtimer; 64 65 if ((newtimer = malloc(sizeof(*newtimer))) == NULL) { 66 logit(LOG_ERR, 67 "<%s> can't allocate memory", __func__); 68 exit(1); 69 } 70 71 memset(newtimer, 0, sizeof(*newtimer)); 72 73 if (timeout == NULL) { 74 logit(LOG_ERR, 75 "<%s> timeout function unspecified", __func__); 76 exit(1); 77 } 78 newtimer->expire = timeout; 79 newtimer->update = update; 80 newtimer->expire_data = timeodata; 81 newtimer->update_data = updatedata; 82 newtimer->tm = tm_max; 83 84 /* link into chain */ 85 TAILQ_INSERT_TAIL(&ra_timer, newtimer, next); 86 87 return(newtimer); 88 } 89 90 void 91 rtadvd_remove_timer(struct rtadvd_timer **timer) 92 { 93 94 if (*timer) { 95 TAILQ_REMOVE(&ra_timer, *timer, next); 96 free(*timer); 97 *timer = NULL; 98 } 99 } 100 101 void 102 rtadvd_set_timer(struct timespec *tm, struct rtadvd_timer *timer) 103 { 104 struct timespec now; 105 106 /* reset the timer */ 107 prog_clock_gettime(CLOCK_MONOTONIC, &now); 108 timespecadd(&now, tm, &timer->tm); 109 110 /* upate the next expiration time */ 111 if (timespeccmp(&timer->tm, &tm_max, <)) 112 tm_max = timer->tm; 113 } 114 115 /* 116 * Check expiration for each timer. If a timer expires, 117 * call the expire function for the timer and update the timer. 118 * Return the next interval for select() call. 119 */ 120 struct timespec * 121 rtadvd_check_timer(void) 122 { 123 static struct timespec returnval; 124 struct timespec now; 125 struct rtadvd_timer *tm, *tmn; 126 127 prog_clock_gettime(CLOCK_MONOTONIC, &now); 128 tm_max = tm_limit; 129 130 TAILQ_FOREACH_SAFE(tm, &ra_timer, next, tmn) { 131 if (timespeccmp(&tm->tm, &now, <=)) { 132 if ((*tm->expire)(tm->expire_data) == NULL) 133 continue; /* the timer was removed */ 134 if (tm->update) 135 (*tm->update)(tm->update_data, &tm->tm); 136 timespecadd(&tm->tm, &now, &tm->tm); 137 } 138 if (timespeccmp(&tm->tm, &tm_max, <)) 139 tm_max = tm->tm; 140 } 141 142 if (timespeccmp(&tm_max, &tm_limit, ==)) 143 return(NULL); 144 if (timespeccmp(&tm_max, &now, <)) { 145 /* this may occur when the interval is too small */ 146 timespecclear(&returnval); 147 } else 148 timespecsub(&tm_max, &now, &returnval); 149 return(&returnval); 150 } 151 152 struct timespec * 153 rtadvd_timer_rest(struct rtadvd_timer *timer) 154 { 155 static struct timespec returnval; 156 struct timespec now; 157 158 prog_clock_gettime(CLOCK_MONOTONIC, &now); 159 if (timespeccmp(&timer->tm, &now, <=)) { 160 logit(LOG_DEBUG, 161 "<%s> a timer must be expired, but not yet", 162 __func__); 163 returnval.tv_sec = 0; 164 returnval.tv_nsec = 0; 165 } 166 else 167 timespecsub(&timer->tm, &now, &returnval); 168 169 return(&returnval); 170 } 171