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
timer_init(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
timer_next_event(struct timespec * ts)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
timer_run(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
timer_add(char * name,u_int32_t when,void (* function)(void *),void * arg)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