1 /* $NetBSD: timer.c,v 1.13 2015/11/11 07:48:41 ozaki-r 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 "prog_ops.h" 44 45 struct rtadvd_timer_head_t ra_timer = TAILQ_HEAD_INITIALIZER(ra_timer); 46 static struct timespec tm_limit = { LONG_MAX, 1000000000L - 1 }; 47 static struct timespec tm_max; 48 49 void 50 rtadvd_timer_init(void) 51 { 52 53 TAILQ_INIT(&ra_timer); 54 tm_max = tm_limit; 55 } 56 57 struct rtadvd_timer * 58 rtadvd_add_timer(struct rtadvd_timer *(*timeout) (void *), 59 void (*update) (void *, struct timespec *), 60 void *timeodata, void *updatedata) 61 { 62 struct rtadvd_timer *newtimer; 63 64 if ((newtimer = malloc(sizeof(*newtimer))) == NULL) { 65 syslog(LOG_ERR, 66 "<%s> can't allocate memory", __func__); 67 exit(1); 68 } 69 70 memset(newtimer, 0, sizeof(*newtimer)); 71 72 if (timeout == NULL) { 73 syslog(LOG_ERR, 74 "<%s> timeout function unspecified", __func__); 75 exit(1); 76 } 77 newtimer->expire = timeout; 78 newtimer->update = update; 79 newtimer->expire_data = timeodata; 80 newtimer->update_data = updatedata; 81 newtimer->tm = tm_max; 82 83 /* link into chain */ 84 TAILQ_INSERT_TAIL(&ra_timer, newtimer, next); 85 86 return(newtimer); 87 } 88 89 void 90 rtadvd_remove_timer(struct rtadvd_timer **timer) 91 { 92 93 if (*timer) { 94 TAILQ_REMOVE(&ra_timer, *timer, next); 95 free(*timer); 96 *timer = NULL; 97 } 98 } 99 100 void 101 rtadvd_set_timer(struct timespec *tm, struct rtadvd_timer *timer) 102 { 103 struct timespec now; 104 105 /* reset the timer */ 106 prog_clock_gettime(CLOCK_MONOTONIC, &now); 107 timespecadd(&now, tm, &timer->tm); 108 109 /* upate the next expiration time */ 110 if (timespeccmp(&timer->tm, &tm_max, <)) 111 tm_max = timer->tm; 112 } 113 114 /* 115 * Check expiration for each timer. If a timer expires, 116 * call the expire function for the timer and update the timer. 117 * Return the next interval for select() call. 118 */ 119 struct timespec * 120 rtadvd_check_timer(void) 121 { 122 static struct timespec returnval; 123 struct timespec now; 124 struct rtadvd_timer *tm, *tmn; 125 126 prog_clock_gettime(CLOCK_MONOTONIC, &now); 127 tm_max = tm_limit; 128 129 TAILQ_FOREACH_SAFE(tm, &ra_timer, next, tmn) { 130 if (timespeccmp(&tm->tm, &now, <=)) { 131 if ((*tm->expire)(tm->expire_data) == NULL) 132 continue; /* the timer was removed */ 133 if (tm->update) 134 (*tm->update)(tm->update_data, &tm->tm); 135 timespecadd(&tm->tm, &now, &tm->tm); 136 } 137 if (timespeccmp(&tm->tm, &tm_max, <)) 138 tm_max = tm->tm; 139 } 140 141 if (timespeccmp(&tm_max, &tm_limit, ==)) 142 return(NULL); 143 if (timespeccmp(&tm_max, &now, <)) { 144 /* this may occur when the interval is too small */ 145 timespecclear(&returnval); 146 } else 147 timespecsub(&tm_max, &now, &returnval); 148 return(&returnval); 149 } 150 151 struct timespec * 152 rtadvd_timer_rest(struct rtadvd_timer *timer) 153 { 154 static struct timespec returnval; 155 struct timespec now; 156 157 prog_clock_gettime(CLOCK_MONOTONIC, &now); 158 if (timespeccmp(&timer->tm, &now, <=)) { 159 syslog(LOG_DEBUG, 160 "<%s> a timer must be expired, but not yet", 161 __func__); 162 returnval.tv_sec = 0; 163 returnval.tv_nsec = 0; 164 } 165 else 166 timespecsub(&timer->tm, &now, &returnval); 167 168 return(&returnval); 169 } 170