1 /* $OpenBSD: timer.c,v 1.7 2018/04/10 15:58:21 cheloha Exp $ */ 2 3 /* 4 * Copyright (c) 2005 H�kan Olsson. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 /* 29 * This code was written under funding by Multicom Security AB. 30 */ 31 32 33 #include <sys/types.h> 34 #include <sys/queue.h> 35 #include <sys/time.h> 36 37 #include <stdlib.h> 38 #include <string.h> 39 #include <time.h> 40 41 #include "sasyncd.h" 42 43 /* 44 * All events have a name, an expiration time and a function to be called 45 * at this time. The queue is always sorted so the next event to happen is 46 * first in the queue. 47 */ 48 struct event { 49 TAILQ_ENTRY (event) next; 50 struct timespec expire; 51 char *name; 52 void (*fun) (void *); 53 void *arg; 54 }; 55 56 static TAILQ_HEAD (event_head, event) events; 57 58 /* Initialize timer event queue. */ 59 void 60 timer_init(void) 61 { 62 TAILQ_INIT(&events); 63 } 64 65 /* 66 * Return the number of seconds until the next event happens. Used for 67 * the select() call in the main loop. 68 */ 69 void 70 timer_next_event(struct timespec *ts) 71 { 72 struct timespec now; 73 struct event *e = TAILQ_FIRST(&events); 74 75 if (e) { 76 clock_gettime(CLOCK_MONOTONIC, &now); 77 if (timespeccmp(&now, &e->expire, >=)) 78 timespecclear(ts); 79 else 80 timespecsub(&e->expire, &now, ts); 81 } else { 82 ts->tv_sec = 60; /* "Best guess". */ 83 ts->tv_nsec = 0; 84 } 85 } 86 87 /* 88 * Whenever select() times out, we have an event that should happen and this 89 * routine gets called. Handle and remove all pending events. 90 */ 91 void 92 timer_run(void) 93 { 94 struct timespec now; 95 struct event *e; 96 97 clock_gettime(CLOCK_MONOTONIC, &now); 98 for (e = TAILQ_FIRST(&events); e && timespeccmp(&now, &e->expire, >=); 99 e = TAILQ_FIRST(&events)) { 100 TAILQ_REMOVE(&events, e, next); 101 log_msg(2, "timer_run: event \"%s\"", 102 e->name ? e->name : "<unknown>"); 103 (*e->fun)(e->arg); 104 if (e->name) 105 free(e->name); 106 free(e); 107 } 108 } 109 110 /* Add a new event. */ 111 int 112 timer_add(char *name, u_int32_t when, void (*function)(void *), void *arg) 113 { 114 struct timespec now, tmp; 115 struct event *e, *new; 116 117 new = calloc(1, sizeof *new); 118 if (!new) { 119 log_err("timer_add: calloc (1, %zu) failed", sizeof *new); 120 return -1; 121 } 122 123 new->name = strdup(name); /* We handle failures here. */ 124 new->fun = function; 125 new->arg = arg; 126 127 tmp.tv_sec = when; 128 tmp.tv_nsec = 0; 129 clock_gettime(CLOCK_MONOTONIC, &now); 130 timespecadd(&now, &tmp, &new->expire); 131 132 log_msg(2, "timer_add: new event \"%s\" (expiring in %us)", 133 name ? name : "<unknown>", when); 134 135 /* Insert the new event in the queue so it's always sorted. */ 136 for (e = TAILQ_FIRST(&events); e; e = TAILQ_NEXT(e, next)) { 137 if (timespeccmp(&new->expire, &e->expire, >=)) 138 continue; 139 TAILQ_INSERT_BEFORE(e, new, next); 140 return 0; 141 } 142 TAILQ_INSERT_TAIL(&events, new, next); 143 return 0; 144 } 145