1 /* $OpenBSD: runq.c,v 1.5 2023/05/31 16:51:46 op Exp $ */
2
3 /*
4 * Copyright (c) 2013,2019 Eric Faurot <eric@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19 #include <stdlib.h>
20 #include <time.h>
21
22 #include "smtpd.h"
23
24 struct job {
25 TAILQ_ENTRY(job) entry;
26 time_t when;
27 void *arg;
28 };
29
30 struct runq {
31 TAILQ_HEAD(, job) jobs;
32 void (*cb)(struct runq *, void *);
33 struct event ev;
34 };
35
36 static void runq_timeout(int, short, void *);
37
38 static struct runq *active;
39
40 static void
runq_reset(struct runq * runq)41 runq_reset(struct runq *runq)
42 {
43 struct timeval tv;
44 struct job *job;
45 time_t now;
46
47 job = TAILQ_FIRST(&runq->jobs);
48 if (job == NULL)
49 return;
50
51 now = time(NULL);
52 if (job->when <= now)
53 tv.tv_sec = 0;
54 else
55 tv.tv_sec = job->when - now;
56 tv.tv_usec = 0;
57 evtimer_add(&runq->ev, &tv);
58 }
59
60 static void
runq_timeout(int fd,short ev,void * arg)61 runq_timeout(int fd, short ev, void *arg)
62 {
63 struct runq *runq = arg;
64 struct job *job;
65 time_t now;
66
67 active = runq;
68 now = time(NULL);
69
70 while((job = TAILQ_FIRST(&runq->jobs))) {
71 if (job->when > now)
72 break;
73 TAILQ_REMOVE(&runq->jobs, job, entry);
74 runq->cb(runq, job->arg);
75 free(job);
76 }
77
78 active = NULL;
79 runq_reset(runq);
80 }
81
82 int
runq_init(struct runq ** runqp,void (* cb)(struct runq *,void *))83 runq_init(struct runq **runqp, void (*cb)(struct runq *, void *))
84 {
85 struct runq *runq;
86
87 runq = malloc(sizeof(*runq));
88 if (runq == NULL)
89 return (0);
90
91 runq->cb = cb;
92 TAILQ_INIT(&runq->jobs);
93 evtimer_set(&runq->ev, runq_timeout, runq);
94
95 *runqp = runq;
96
97 return (1);
98 }
99
100 int
runq_schedule(struct runq * runq,time_t delay,void * arg)101 runq_schedule(struct runq *runq, time_t delay, void *arg)
102 {
103 time_t t;
104
105 time(&t);
106 return runq_schedule_at(runq, t + delay, arg);
107 }
108
109 int
runq_schedule_at(struct runq * runq,time_t when,void * arg)110 runq_schedule_at(struct runq *runq, time_t when, void *arg)
111 {
112 struct job *job, *tmpjob;
113
114 job = malloc(sizeof(*job));
115 if (job == NULL)
116 return (0);
117
118 job->arg = arg;
119 job->when = when;
120
121 TAILQ_FOREACH(tmpjob, &runq->jobs, entry) {
122 if (tmpjob->when > job->when) {
123 TAILQ_INSERT_BEFORE(tmpjob, job, entry);
124 goto done;
125 }
126 }
127 TAILQ_INSERT_TAIL(&runq->jobs, job, entry);
128
129 done:
130 if (runq != active && job == TAILQ_FIRST(&runq->jobs)) {
131 evtimer_del(&runq->ev);
132 runq_reset(runq);
133 }
134 return (1);
135 }
136
137 int
runq_cancel(struct runq * runq,void * arg)138 runq_cancel(struct runq *runq, void *arg)
139 {
140 struct job *job, *first;
141
142 first = TAILQ_FIRST(&runq->jobs);
143 TAILQ_FOREACH(job, &runq->jobs, entry) {
144 if (job->arg == arg) {
145 TAILQ_REMOVE(&runq->jobs, job, entry);
146 free(job);
147 if (runq != active && job == first) {
148 evtimer_del(&runq->ev);
149 runq_reset(runq);
150 }
151 return (1);
152 }
153 }
154
155 return (0);
156 }
157
158 int
runq_pending(struct runq * runq,void * arg,time_t * when)159 runq_pending(struct runq *runq, void *arg, time_t *when)
160 {
161 struct job *job;
162
163 TAILQ_FOREACH(job, &runq->jobs, entry) {
164 if (job->arg == arg) {
165 if (when)
166 *when = job->when;
167 return (1);
168 }
169 }
170
171 return (0);
172 }
173