1 /* 2 * Copyright (C) 1998 WIDE Project. 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 project 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 PROJECT 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 PROJECT 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 * $FreeBSD$ 30 */ 31 32 #include <sys/time.h> 33 34 #include <unistd.h> 35 #include <syslog.h> 36 #include <stdlib.h> 37 #include <string.h> 38 #ifdef __NetBSD__ 39 #include <search.h> 40 #endif 41 #include "timer.h" 42 43 static struct rtadvd_timer timer_head; 44 45 #define MILLION 1000000 46 47 static struct timeval tm_max = {0x7fffffff, 0x7fffffff}; 48 49 void 50 rtadvd_timer_init() 51 { 52 memset(&timer_head, 0, sizeof(timer_head)); 53 54 timer_head.next = timer_head.prev = &timer_head; 55 timer_head.tm = tm_max; 56 } 57 58 struct rtadvd_timer * 59 rtadvd_add_timer(void (*timeout) __P((void *)), 60 void (*update) __P((void *, struct timeval *)), 61 void *timeodata, void *updatedata) 62 { 63 struct rtadvd_timer *newtimer; 64 65 if ((newtimer = malloc(sizeof(*newtimer))) == NULL) { 66 syslog(LOG_ERR, 67 "<%s> can't allocate memory", __FUNCTION__); 68 exit(1); 69 } 70 71 memset(newtimer, 0, sizeof(*newtimer)); 72 73 if (timeout == NULL) { 74 syslog(LOG_ERR, 75 "<%s> timeout function unspecfied", __FUNCTION__); 76 exit(1); 77 } 78 if (update == NULL) { 79 syslog(LOG_ERR, 80 "<%s> update function unspecfied", __FUNCTION__); 81 exit(1); 82 } 83 newtimer->expire = timeout; 84 newtimer->update = update; 85 newtimer->expire_data = timeodata; 86 newtimer->update_data = updatedata; 87 newtimer->tm = tm_max; 88 89 /* link into chain */ 90 insque(newtimer, &timer_head); 91 92 return(newtimer); 93 } 94 95 void 96 rtadvd_set_timer(struct timeval *tm, struct rtadvd_timer *timer) 97 { 98 struct timeval now; 99 100 /* reset the timer */ 101 gettimeofday(&now, NULL); 102 103 TIMEVAL_ADD(&now, tm, &timer->tm); 104 105 /* update the next expiration time */ 106 if (TIMEVAL_LT(timer->tm, timer_head.tm)) 107 timer_head.tm = timer->tm; 108 109 return; 110 } 111 112 /* 113 * Check expiration for each timer. If a timer is expired, 114 * call the expire function for the timer and update the timer. 115 * Return the next interval for select() call. 116 */ 117 struct timeval * 118 rtadvd_check_timer() 119 { 120 static struct timeval returnval; 121 struct timeval now; 122 struct rtadvd_timer *tm = timer_head.next; 123 124 gettimeofday(&now, NULL); 125 126 timer_head.tm = tm_max; 127 128 while(tm != &timer_head) { 129 if (TIMEVAL_LEQ(tm->tm, now)) { 130 (*tm->expire)(tm->expire_data); 131 (*tm->update)(tm->update_data, &tm->tm); 132 TIMEVAL_ADD(&tm->tm, &now, &tm->tm); 133 } 134 135 if (TIMEVAL_LT(tm->tm, timer_head.tm)) 136 timer_head.tm = tm->tm; 137 138 tm = tm->next; 139 } 140 141 if (TIMEVAL_LT(timer_head.tm, now)) { 142 /* this may occur when the interval is too small */ 143 returnval.tv_sec = returnval.tv_usec = 0; 144 } 145 else 146 TIMEVAL_SUB(&timer_head.tm, &now, &returnval); 147 return(&returnval); 148 } 149 150 struct timeval * 151 rtadvd_timer_rest(struct rtadvd_timer *timer) 152 { 153 static struct timeval returnval, now; 154 155 gettimeofday(&now, NULL); 156 if (TIMEVAL_LEQ(timer->tm, now)) { 157 syslog(LOG_DEBUG, 158 "<%s> a timer must be expired, but not yet", 159 __FUNCTION__); 160 returnval.tv_sec = returnval.tv_usec = 0; 161 } 162 else 163 TIMEVAL_SUB(&timer->tm, &now, &returnval); 164 165 return(&returnval); 166 } 167 168 /* result = a + b */ 169 void 170 TIMEVAL_ADD(struct timeval *a, struct timeval *b, struct timeval *result) 171 { 172 long l; 173 174 if ((l = a->tv_usec + b->tv_usec) < MILLION) { 175 result->tv_usec = l; 176 result->tv_sec = a->tv_sec + b->tv_sec; 177 } 178 else { 179 result->tv_usec = l - MILLION; 180 result->tv_sec = a->tv_sec + b->tv_sec + 1; 181 } 182 } 183 184 /* 185 * result = a - b 186 * XXX: this function assumes that a >= b. 187 */ 188 void 189 TIMEVAL_SUB(struct timeval *a, struct timeval *b, struct timeval *result) 190 { 191 long l; 192 193 if ((l = a->tv_usec - b->tv_usec) >= 0) { 194 result->tv_usec = l; 195 result->tv_sec = a->tv_sec - b->tv_sec; 196 } 197 else { 198 result->tv_usec = MILLION + l; 199 result->tv_sec = a->tv_sec - b->tv_sec - 1; 200 } 201 } 202