t_sem.c revision 314817 
1/* $NetBSD: t_sem.c,v 1.3 2017/01/14 20:58:20 christos Exp $ */
2
3/*
4 * Copyright (c) 2008, 2010 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29/*
30 * Copyright (C) 2000 Jason Evans <jasone@freebsd.org>.
31 * All rights reserved.
32 *
33 * Redistribution and use in source and binary forms, with or without
34 * modification, are permitted provided that the following conditions
35 * are met:
36 * 1. Redistributions of source code must retain the above copyright
37 *    notice(s), this list of conditions and the following disclaimer as
38 *    the first lines of this file unmodified other than the possible
39 *    addition of one or more copyright notices.
40 * 2. Redistributions in binary form must reproduce the above copyright
41 *    notice(s), this list of conditions and the following disclaimer in
42 *    the documentation and/or other materials provided with the
43 *    distribution.
44 *
45 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
46 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
47 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
48 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
49 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
50 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
51 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
52 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
53 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
54 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
55 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
56 */
57
58#include <sys/cdefs.h>
59__COPYRIGHT("@(#) Copyright (c) 2008, 2010\
60 The NetBSD Foundation, inc. All rights reserved.");
61__RCSID("$NetBSD: t_sem.c,v 1.3 2017/01/14 20:58:20 christos Exp $");
62
63#include <sys/wait.h>
64
65#include <errno.h>
66#include <fcntl.h>
67#include <semaphore.h>
68#include <stdio.h>
69#include <unistd.h>
70
71#include <atf-c.h>
72
73#define NCHILDREN 10
74
75ATF_TC_WITH_CLEANUP(basic);
76ATF_TC_HEAD(basic, tc)
77{
78	atf_tc_set_md_var(tc, "descr", "Checks basic functionality of POSIX "
79	    "semaphores");
80}
81ATF_TC_BODY(basic, tc)
82{
83	int val;
84	sem_t *sem_b;
85
86	if (sysconf(_SC_SEMAPHORES) == -1)
87		atf_tc_skip("POSIX semaphores not supported");
88
89	sem_b = sem_open("/sem_b", O_CREAT | O_EXCL, 0644, 0);
90	ATF_REQUIRE(sem_b != SEM_FAILED);
91
92	ATF_REQUIRE_EQ(sem_getvalue(sem_b, &val), 0);
93	ATF_REQUIRE_EQ(val, 0);
94
95	ATF_REQUIRE_EQ(sem_post(sem_b), 0);
96	ATF_REQUIRE_EQ(sem_getvalue(sem_b, &val), 0);
97	ATF_REQUIRE_EQ(val, 1);
98
99	ATF_REQUIRE_EQ(sem_wait(sem_b), 0);
100	ATF_REQUIRE_EQ(sem_trywait(sem_b), -1);
101	ATF_REQUIRE_EQ(errno, EAGAIN);
102	ATF_REQUIRE_EQ(sem_post(sem_b), 0);
103	ATF_REQUIRE_EQ(sem_trywait(sem_b), 0);
104	ATF_REQUIRE_EQ(sem_post(sem_b), 0);
105	ATF_REQUIRE_EQ(sem_wait(sem_b), 0);
106	ATF_REQUIRE_EQ(sem_post(sem_b), 0);
107
108	ATF_REQUIRE_EQ(sem_close(sem_b), 0);
109	ATF_REQUIRE_EQ(sem_unlink("/sem_b"), 0);
110}
111ATF_TC_CLEANUP(basic, tc)
112{
113	(void)sem_unlink("/sem_b");
114}
115
116ATF_TC_WITH_CLEANUP(child);
117ATF_TC_HEAD(child, tc)
118{
119	atf_tc_set_md_var(tc, "descr", "Checks using semaphores to synchronize "
120	    "parent with multiple child processes");
121}
122ATF_TC_BODY(child, tc)
123{
124	pid_t children[NCHILDREN];
125	unsigned i, j;
126	sem_t *sem_a;
127	int status;
128
129	pid_t pid;
130
131	if (sysconf(_SC_SEMAPHORES) == -1)
132		atf_tc_skip("POSIX semaphores not supported");
133
134	sem_a = sem_open("/sem_a", O_CREAT | O_EXCL, 0644, 0);
135	ATF_REQUIRE(sem_a != SEM_FAILED);
136
137	for (j = 1; j <= 2; j++) {
138		for (i = 0; i < NCHILDREN; i++) {
139			switch ((pid = fork())) {
140			case -1:
141				atf_tc_fail("fork() returned -1");
142			case 0:
143				printf("PID %d waiting for semaphore...\n",
144				    getpid());
145				ATF_REQUIRE_MSG(sem_wait(sem_a) == 0,
146				    "sem_wait failed; iteration %d", j);
147				printf("PID %d got semaphore\n", getpid());
148				_exit(0);
149			default:
150				children[i] = pid;
151				break;
152			}
153		}
154
155		for (i = 0; i < NCHILDREN; i++) {
156			sleep(1);
157			printf("main loop %d: posting...\n", j);
158			ATF_REQUIRE_EQ(sem_post(sem_a), 0);
159		}
160
161		for (i = 0; i < NCHILDREN; i++) {
162			ATF_REQUIRE_EQ(waitpid(children[i], &status, 0), children[i]);
163			ATF_REQUIRE(WIFEXITED(status));
164			ATF_REQUIRE_EQ(WEXITSTATUS(status), 0);
165		}
166	}
167
168	ATF_REQUIRE_EQ(sem_close(sem_a), 0);
169	ATF_REQUIRE_EQ(sem_unlink("/sem_a"), 0);
170}
171ATF_TC_CLEANUP(child, tc)
172{
173	(void)sem_unlink("/sem_a");
174}
175
176ATF_TP_ADD_TCS(tp)
177{
178
179	ATF_TP_ADD_TC(tp, basic);
180	ATF_TP_ADD_TC(tp, child);
181
182	return atf_no_error();
183}
184