1/*-
2 * Copyright (c) 2007-2009 Dag-Erling Coïdan Smørgrav
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 *    in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD$");
30
31#include <sys/param.h>
32#include <sys/wait.h>
33
34#include <fcntl.h>
35#include <errno.h>
36#include <signal.h>
37#include <stdint.h>
38#include <stdio.h>
39#include <stdlib.h>
40#include <string.h>
41#include <unistd.h>
42
43#include <libutil.h>
44
45/*
46 * We need a signal handler so kill(2) will interrupt our child's
47 * select(2) instead of killing it.
48 */
49static void
50signal_handler(int sig)
51{
52	(void)sig;
53}
54
55/*
56 * Test that pidfile_open() can create a pidfile and that pidfile_write()
57 * can write to it.
58 */
59static const char *
60test_pidfile_uncontested(void)
61{
62	const char *fn = "test_pidfile_uncontested";
63	struct pidfh *pf;
64	pid_t other = 0;
65
66	unlink(fn);
67	pf = pidfile_open(fn, 0600, &other);
68	if (pf == NULL && other != 0)
69		return ("pidfile exists and is locked");
70	if (pf == NULL)
71		return (strerror(errno));
72	if (pidfile_write(pf) != 0) {
73		pidfile_close(pf);
74		unlink(fn);
75		return ("failed to write PID");
76	}
77	pidfile_close(pf);
78	unlink(fn);
79	return (NULL);
80}
81
82/*
83 * Test that pidfile_open() locks against self.
84 */
85static const char *
86test_pidfile_self(void)
87{
88	const char *fn = "test_pidfile_self";
89	struct pidfh *pf1, *pf2;
90	pid_t other = 0;
91	int serrno;
92
93	unlink(fn);
94	pf1 = pidfile_open(fn, 0600, &other);
95	if (pf1 == NULL && other != 0)
96		return ("pidfile exists and is locked");
97	if (pf1 == NULL)
98		return (strerror(errno));
99	if (pidfile_write(pf1) != 0) {
100		serrno = errno;
101		pidfile_close(pf1);
102		unlink(fn);
103		return (strerror(serrno));
104	}
105	// second open should fail
106	pf2 = pidfile_open(fn, 0600, &other);
107	if (pf2 != NULL) {
108		pidfile_close(pf1);
109		pidfile_close(pf2);
110		unlink(fn);
111		return ("managed to opened pidfile twice");
112	}
113	if (other != getpid()) {
114		pidfile_close(pf1);
115		unlink(fn);
116		return ("pidfile contained wrong PID");
117	}
118	pidfile_close(pf1);
119	unlink(fn);
120	return (NULL);
121}
122
123/*
124 * Common code for test_pidfile_{contested,inherited}.
125 */
126static const char *
127common_test_pidfile_child(const char *fn, int parent_open)
128{
129	struct pidfh *pf = NULL;
130	pid_t other = 0, pid = 0;
131	int fd[2], serrno, status;
132	char ch;
133
134	unlink(fn);
135	if (pipe(fd) != 0)
136		return (strerror(errno));
137
138	if (parent_open) {
139		pf = pidfile_open(fn, 0600, &other);
140		if (pf == NULL && other != 0)
141			return ("pidfile exists and is locked");
142		if (pf == NULL)
143			return (strerror(errno));
144	}
145
146	pid = fork();
147	if (pid == -1)
148		return (strerror(errno));
149	if (pid == 0) {
150		// child
151		close(fd[0]);
152		signal(SIGINT, signal_handler);
153		if (!parent_open) {
154			pf = pidfile_open(fn, 0600, &other);
155			if (pf == NULL && other != 0)
156				return ("pidfile exists and is locked");
157			if (pf == NULL)
158				return (strerror(errno));
159		}
160		if (pidfile_write(pf) != 0) {
161			serrno = errno;
162			pidfile_close(pf);
163			unlink(fn);
164			return (strerror(serrno));
165		}
166		if (pf == NULL)
167			_exit(1);
168		if (pidfile_write(pf) != 0)
169			_exit(1);
170		if (write(fd[1], "*", 1) != 1)
171			_exit(1);
172		select(0, 0, 0, 0, 0);
173		_exit(0);
174	}
175	// parent
176	close(fd[1]);
177	if (pf)
178		pidfile_close(pf);
179
180	// wait for the child to signal us
181	if (read(fd[0], &ch, 1) != 1) {
182		serrno = errno;
183		unlink(fn);
184		kill(pid, SIGTERM);
185		errno = serrno;
186		return (strerror(errno));
187	}
188
189	// We shouldn't be able to lock the same pidfile as our child
190	pf = pidfile_open(fn, 0600, &other);
191	if (pf != NULL) {
192		pidfile_close(pf);
193		unlink(fn);
194		return ("managed to lock contested pidfile");
195	}
196
197	// Failed to lock, but not because it was contested
198	if (other == 0) {
199		unlink(fn);
200		return (strerror(errno));
201	}
202
203	// Locked by the wrong process
204	if (other != pid) {
205		unlink(fn);
206		return ("pidfile contained wrong PID");
207	}
208
209	// check our child's fate
210	if (pf)
211		pidfile_close(pf);
212	unlink(fn);
213	if (kill(pid, SIGINT) != 0)
214		return (strerror(errno));
215	if (waitpid(pid, &status, 0) == -1)
216		return (strerror(errno));
217	if (WIFSIGNALED(status))
218		return ("child caught signal");
219	if (WEXITSTATUS(status) != 0)
220		return ("child returned non-zero status");
221
222	// success
223	return (NULL);
224}
225
226/*
227 * Test that pidfile_open() fails when attempting to open a pidfile that
228 * is already locked, and that it returns the correct PID.
229 */
230static const char *
231test_pidfile_contested(void)
232{
233	const char *fn = "test_pidfile_contested";
234	const char *result;
235
236	result = common_test_pidfile_child(fn, 0);
237	return (result);
238}
239
240/*
241 * Test that the pidfile lock is inherited.
242 */
243static const char *
244test_pidfile_inherited(void)
245{
246	const char *fn = "test_pidfile_inherited";
247	const char *result;
248
249	result = common_test_pidfile_child(fn, 1);
250	return (result);
251}
252
253static struct test {
254	const char *name;
255	const char *(*func)(void);
256} t[] = {
257	{ "pidfile_uncontested", test_pidfile_uncontested },
258	{ "pidfile_self", test_pidfile_self },
259	{ "pidfile_contested", test_pidfile_contested },
260	{ "pidfile_inherited", test_pidfile_inherited },
261};
262
263int
264main(void)
265{
266	const char *result;
267	int i, nt;
268
269	nt = sizeof(t) / sizeof(*t);
270	printf("1..%d\n", nt);
271	for (i = 0; i < nt; ++i) {
272		if ((result = t[i].func()) != NULL)
273			printf("not ok %d - %s # %s\n", i + 1,
274			    t[i].name, result);
275		else
276			printf("ok %d - %s\n", i + 1,
277			    t[i].name);
278	}
279	exit(0);
280}
281