xref: /netbsd-src/external/bsd/cron/dist/job.c (revision cd1156524477b27e01412687e65720a208f78651)
1 /*	$NetBSD: job.c,v 1.3 2020/04/18 19:32:19 christos Exp $	*/
2 
3 /* Copyright 1988,1990,1993,1994 by Paul Vixie
4  * All rights reserved
5  */
6 
7 /*
8  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
9  * Copyright (c) 1997,2000 by Internet Software Consortium, Inc.
10  *
11  * Permission to use, copy, modify, and distribute this software for any
12  * purpose with or without fee is hereby granted, provided that the above
13  * copyright notice and this permission notice appear in all copies.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
16  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
17  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
18  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
19  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
20  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
21  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
22  */
23 #include <sys/cdefs.h>
24 
25 #if !defined(lint) && !defined(LINT)
26 #if 0
27 static char rcsid[] = "Id: job.c,v 1.6 2004/01/23 18:56:43 vixie Exp";
28 #else
29 __RCSID("$NetBSD: job.c,v 1.3 2020/04/18 19:32:19 christos Exp $");
30 #endif
31 #endif
32 
33 #include "cron.h"
34 
35 typedef	struct _job {
36 	SIMPLEQ_ENTRY(_job) entries;
37 	entry		*e;
38 	user		*u;
39 	time_t		t;
40 	pid_t		pid;
41 } job;
42 
43 static SIMPLEQ_HEAD(job_queue, _job) jobs = SIMPLEQ_HEAD_INITIALIZER(jobs);
44 
45 static int okay_to_go(job *);
46 
47 void
job_add(entry * e,user * u,time_t target_time)48 job_add(entry *e, user *u, time_t target_time) {
49 	job *j;
50 
51 	/* if already on queue, keep going */
52 	SIMPLEQ_FOREACH(j, &jobs, entries) {
53 		if (j->e == e && j->u == u) {
54 			j->t = target_time;
55 			return;
56 		}
57 	}
58 
59 	/* build a job queue element */
60 	if ((j = calloc(1, sizeof(*j))) == NULL)
61 		return;
62 	j->e = e;
63 	j->u = u;
64 	j->t = target_time;
65 	j->pid = -1;
66 
67 	/* add it to the tail */
68 	SIMPLEQ_INSERT_TAIL(&jobs, j, entries);
69 }
70 
71 void
job_remove(entry * e,user * u)72 job_remove(entry *e, user *u)
73 {
74 	job *j, *prev = NULL;
75 
76 	SIMPLEQ_FOREACH(j, &jobs, entries) {
77 		if (j->e == e && j->u == u) {
78 			if (prev == NULL)
79 				SIMPLEQ_REMOVE_HEAD(&jobs, entries);
80 			else
81 				SIMPLEQ_REMOVE_AFTER(&jobs, prev, entries);
82 			free(j);
83 			break;
84 		}
85 		prev = j;
86 	}
87 }
88 
89 void
job_exit(pid_t jobpid)90 job_exit(pid_t jobpid)
91 {
92 	job *j, *prev = NULL;
93 
94 	/* If a singleton exited, remove and free it. */
95 	SIMPLEQ_FOREACH(j, &jobs, entries) {
96 		if (jobpid == j->pid) {
97 			if (prev == NULL)
98 				SIMPLEQ_REMOVE_HEAD(&jobs, entries);
99 			else
100 				SIMPLEQ_REMOVE_AFTER(&jobs, prev, entries);
101 			free(j);
102 			break;
103 		}
104 		prev = j;
105 	}
106 }
107 
108 int
job_runqueue(void)109 job_runqueue(void) {
110 	struct job_queue singletons = SIMPLEQ_HEAD_INITIALIZER(singletons);
111 	job *j;
112 	int run = 0;
113 
114 	while ((j = SIMPLEQ_FIRST(&jobs))) {
115 		SIMPLEQ_REMOVE_HEAD(&jobs, entries);
116 		if (okay_to_go(j)) {
117 			j->pid = do_command(j->e, j->u);
118 			run++;
119 		} else {
120 			char *x = mkprints(j->e->cmd, strlen(j->e->cmd));
121 			char *usernm = env_get("LOGNAME", j->e->envp);
122 
123 			log_it(usernm, getpid(), "CMD (skipped)", x);
124 			free(x);
125 		}
126 		if (j->pid != -1)
127 			SIMPLEQ_INSERT_TAIL(&singletons, j, entries);
128 		else
129 			free(j);
130 	}
131 	SIMPLEQ_CONCAT(&jobs, &singletons);
132 	return (run);
133 }
134 
135 
136 static int
okay_to_go(job * j)137 okay_to_go(job *j)
138 {
139 	char *within, *t;
140 	long delta;
141 
142 	if (j->pid != -1)
143 		return 0;
144 
145 	if (j->e->flags & WHEN_REBOOT)
146 		return (1);
147 
148 	within = env_get("CRON_WITHIN", j->e->envp);
149 	if (within == NULL)
150 		return (1);
151 
152 	/* XXX handle 2m, 4h, etc? */
153 	errno = 0;
154 	delta = strtol(within, &t, 10);
155 	if (errno == ERANGE || *t != '\0' || delta <= 0)
156 		return (1);
157 
158 	return ((j->t + delta) > time(NULL));
159 }
160