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/time.h>
64 #include <sys/wait.h>
65
66 #include <errno.h>
67 #include <fcntl.h>
68 #include <semaphore.h>
69 #include <signal.h>
70 #include <stdio.h>
71 #include <time.h>
72 #include <unistd.h>
73
74 #include <atf-c.h>
75
76 #define NCHILDREN 10
77
78 #define SEM_REQUIRE(x) \
79 ATF_REQUIRE_EQ_MSG(x, 0, "%s", strerror(errno))
80
81 ATF_TC_WITH_CLEANUP(basic);
ATF_TC_HEAD(basic,tc)82 ATF_TC_HEAD(basic, tc)
83 {
84 atf_tc_set_md_var(tc, "descr", "Checks basic functionality of POSIX "
85 "semaphores");
86 }
ATF_TC_BODY(basic,tc)87 ATF_TC_BODY(basic, tc)
88 {
89 int val;
90 sem_t *sem_b;
91
92 if (sysconf(_SC_SEMAPHORES) == -1)
93 atf_tc_skip("POSIX semaphores not supported");
94
95 sem_b = sem_open("/sem_b", O_CREAT | O_EXCL, 0644, 0);
96 ATF_REQUIRE(sem_b != SEM_FAILED);
97
98 ATF_REQUIRE_EQ(sem_getvalue(sem_b, &val), 0);
99 ATF_REQUIRE_EQ(val, 0);
100
101 ATF_REQUIRE_EQ(sem_post(sem_b), 0);
102 ATF_REQUIRE_EQ(sem_getvalue(sem_b, &val), 0);
103 ATF_REQUIRE_EQ(val, 1);
104
105 ATF_REQUIRE_EQ(sem_wait(sem_b), 0);
106 ATF_REQUIRE_EQ(sem_trywait(sem_b), -1);
107 ATF_REQUIRE_EQ(errno, EAGAIN);
108 ATF_REQUIRE_EQ(sem_post(sem_b), 0);
109 ATF_REQUIRE_EQ(sem_trywait(sem_b), 0);
110 ATF_REQUIRE_EQ(sem_post(sem_b), 0);
111 ATF_REQUIRE_EQ(sem_wait(sem_b), 0);
112 ATF_REQUIRE_EQ(sem_post(sem_b), 0);
113
114 ATF_REQUIRE_EQ(sem_close(sem_b), 0);
115 ATF_REQUIRE_EQ(sem_unlink("/sem_b"), 0);
116 }
ATF_TC_CLEANUP(basic,tc)117 ATF_TC_CLEANUP(basic, tc)
118 {
119 (void)sem_unlink("/sem_b");
120 }
121
122 ATF_TC_WITH_CLEANUP(child);
ATF_TC_HEAD(child,tc)123 ATF_TC_HEAD(child, tc)
124 {
125 atf_tc_set_md_var(tc, "descr", "Checks using semaphores to synchronize "
126 "parent with multiple child processes");
127 atf_tc_set_md_var(tc, "timeout", "5");
128 }
ATF_TC_BODY(child,tc)129 ATF_TC_BODY(child, tc)
130 {
131 pid_t children[NCHILDREN];
132 unsigned i, j;
133 sem_t *sem_a;
134 int status;
135
136 pid_t pid;
137
138 if (sysconf(_SC_SEMAPHORES) == -1)
139 atf_tc_skip("POSIX semaphores not supported");
140
141 sem_a = sem_open("/sem_a", O_CREAT | O_EXCL, 0644, 0);
142 ATF_REQUIRE(sem_a != SEM_FAILED);
143
144 for (j = 1; j <= 2; j++) {
145 for (i = 0; i < NCHILDREN; i++) {
146 switch ((pid = fork())) {
147 case -1:
148 atf_tc_fail("fork() returned -1");
149 case 0:
150 printf("PID %d waiting for semaphore...\n",
151 getpid());
152 ATF_REQUIRE_MSG(sem_wait(sem_a) == 0,
153 "sem_wait failed; iteration %d", j);
154 printf("PID %d got semaphore\n", getpid());
155 _exit(0);
156 default:
157 children[i] = pid;
158 break;
159 }
160 }
161
162 for (i = 0; i < NCHILDREN; i++) {
163 usleep(100000);
164 printf("main loop %d: posting...\n", j);
165 ATF_REQUIRE_EQ(sem_post(sem_a), 0);
166 }
167
168 for (i = 0; i < NCHILDREN; i++) {
169 ATF_REQUIRE_EQ(waitpid(children[i], &status, 0), children[i]);
170 ATF_REQUIRE(WIFEXITED(status));
171 ATF_REQUIRE_EQ(WEXITSTATUS(status), 0);
172 }
173 }
174
175 ATF_REQUIRE_EQ(sem_close(sem_a), 0);
176 ATF_REQUIRE_EQ(sem_unlink("/sem_a"), 0);
177 }
ATF_TC_CLEANUP(child,tc)178 ATF_TC_CLEANUP(child, tc)
179 {
180 (void)sem_unlink("/sem_a");
181 }
182
183 static inline void
timespec_add_ms(struct timespec * ts,int ms)184 timespec_add_ms(struct timespec *ts, int ms)
185 {
186 ts->tv_nsec += ms * 1000*1000;
187 if (ts->tv_nsec > 1000*1000*1000) {
188 ts->tv_sec++;
189 ts->tv_nsec -= 1000*1000*1000;
190 }
191 }
192
193 static volatile sig_atomic_t got_sigalrm = 0;
194
195 static void
sigalrm_handler(int sig __unused)196 sigalrm_handler(int sig __unused)
197 {
198 got_sigalrm = 1;
199 }
200
201 ATF_TC(timedwait);
ATF_TC_HEAD(timedwait,tc)202 ATF_TC_HEAD(timedwait, tc)
203 {
204 atf_tc_set_md_var(tc, "descr", "Tests sem_timedwait(3)"
205 #ifdef __FreeBSD__
206 " and sem_clockwait_np(3)"
207 #endif
208 );
209 atf_tc_set_md_var(tc, "timeout", "20");
210 }
ATF_TC_BODY(timedwait,tc)211 ATF_TC_BODY(timedwait, tc)
212 {
213 struct timespec ts;
214 sem_t sem;
215
216 SEM_REQUIRE(sem_init(&sem, 0, 0));
217 SEM_REQUIRE(sem_post(&sem));
218 ATF_REQUIRE_MSG(clock_gettime(CLOCK_REALTIME, &ts) == 0,
219 "%s", strerror(errno));
220 timespec_add_ms(&ts, 100);
221 SEM_REQUIRE(sem_timedwait(&sem, &ts));
222 ATF_REQUIRE_ERRNO(ETIMEDOUT, sem_timedwait(&sem, &ts));
223 ts.tv_sec--;
224 ATF_REQUIRE_ERRNO(ETIMEDOUT, sem_timedwait(&sem, &ts));
225 SEM_REQUIRE(sem_post(&sem));
226 SEM_REQUIRE(sem_timedwait(&sem, &ts));
227
228 /* timespec validation, in the past */
229 ts.tv_nsec += 1000*1000*1000;
230 ATF_REQUIRE_ERRNO(EINVAL, sem_timedwait(&sem, &ts));
231 ts.tv_nsec = -1;
232 ATF_REQUIRE_ERRNO(EINVAL, sem_timedwait(&sem, &ts));
233 /* timespec validation, in the future */
234 ATF_REQUIRE_MSG(clock_gettime(CLOCK_REALTIME, &ts) == 0,
235 "%s", strerror(errno));
236 ts.tv_sec++;
237 ts.tv_nsec = 1000*1000*1000;
238 ATF_REQUIRE_ERRNO(EINVAL, sem_timedwait(&sem, &ts));
239 ts.tv_nsec = -1;
240 ATF_REQUIRE_ERRNO(EINVAL, sem_timedwait(&sem, &ts));
241
242 /* EINTR */
243 struct sigaction act = {
244 .sa_handler = sigalrm_handler,
245 .sa_flags = 0 /* not SA_RESTART */
246 };
247 ATF_REQUIRE_MSG(sigemptyset(&act.sa_mask) == 0,
248 "%s", strerror(errno));
249 ATF_REQUIRE_MSG(sigaction(SIGALRM, &act, NULL) == 0,
250 "%s", strerror(errno));
251 struct itimerval it = {
252 .it_value.tv_usec = 50*1000
253 };
254 ATF_REQUIRE_MSG(setitimer(ITIMER_REAL, &it, NULL) == 0,
255 "%s", strerror(errno));
256 ATF_REQUIRE_MSG(clock_gettime(CLOCK_REALTIME, &ts) == 0,
257 "%s", strerror(errno));
258 timespec_add_ms(&ts, 100);
259 ATF_REQUIRE_ERRNO(EINTR, sem_timedwait(&sem, &ts));
260 ATF_REQUIRE_MSG(got_sigalrm, "did not get SIGALRM");
261
262 #ifdef __FreeBSD__
263 /* CLOCK_MONOTONIC, absolute */
264 SEM_REQUIRE(sem_post(&sem));
265 ATF_REQUIRE_MSG(clock_gettime(CLOCK_MONOTONIC, &ts) == 0,
266 "%s", strerror(errno));
267 timespec_add_ms(&ts, 100);
268 SEM_REQUIRE(sem_clockwait_np(&sem, CLOCK_MONOTONIC, TIMER_ABSTIME,
269 &ts, NULL));
270 ATF_REQUIRE_ERRNO(ETIMEDOUT,
271 sem_clockwait_np(&sem, CLOCK_MONOTONIC, TIMER_ABSTIME, &ts, NULL));
272
273 /* CLOCK_MONOTONIC, relative */
274 SEM_REQUIRE(sem_post(&sem));
275 ts.tv_sec = 0;
276 ts.tv_nsec = 100*1000*1000;
277 SEM_REQUIRE(sem_clockwait_np(&sem, CLOCK_MONOTONIC, 0,
278 &ts, NULL));
279 ATF_REQUIRE_ERRNO(ETIMEDOUT,
280 sem_clockwait_np(&sem, CLOCK_MONOTONIC, 0, &ts, NULL));
281
282 /* absolute does not update remaining time on EINTR */
283 struct timespec remain = {42, 1000*1000*1000};
284 got_sigalrm = 0;
285 it.it_value.tv_usec = 50*1000;
286 ATF_REQUIRE_MSG(setitimer(ITIMER_REAL, &it, NULL) == 0,
287 "%s", strerror(errno));
288 ATF_REQUIRE_MSG(clock_gettime(CLOCK_MONOTONIC, &ts) == 0,
289 "%s", strerror(errno));
290 timespec_add_ms(&ts, 100);
291 ATF_REQUIRE_ERRNO(EINTR, sem_clockwait_np(&sem, CLOCK_MONOTONIC,
292 TIMER_ABSTIME, &ts, &remain));
293 ATF_REQUIRE_MSG(got_sigalrm, "did not get SIGALRM");
294 ATF_REQUIRE_MSG(remain.tv_sec == 42 && remain.tv_nsec == 1000*1000*1000,
295 "an absolute clockwait modified the remaining time on EINTR");
296
297 /* relative updates remaining time on EINTR */
298 remain.tv_sec = 42;
299 remain.tv_nsec = 1000*1000*1000;
300 got_sigalrm = 0;
301 it.it_value.tv_usec = 50*1000;
302 ATF_REQUIRE_MSG(setitimer(ITIMER_REAL, &it, NULL) == 0,
303 "%s", strerror(errno));
304 ts.tv_sec = 0;
305 ts.tv_nsec = 100*1000*1000;
306 ATF_REQUIRE_ERRNO(EINTR, sem_clockwait_np(&sem, CLOCK_MONOTONIC, 0, &ts,
307 &remain));
308 ATF_REQUIRE_MSG(got_sigalrm, "did not get SIGALRM");
309 /*
310 * If this nsec comparison turns out to be unreliable due to timing,
311 * it could simply check that nsec < 100 ms.
312 */
313 ATF_REQUIRE_MSG(remain.tv_sec == 0 &&
314 remain.tv_nsec >= 25*1000*1000 &&
315 remain.tv_nsec <= 75*1000*1000,
316 "the remaining time was not as expected when a relative clockwait"
317 " got EINTR" );
318 #endif
319 }
320
ATF_TP_ADD_TCS(tp)321 ATF_TP_ADD_TCS(tp)
322 {
323
324 ATF_TP_ADD_TC(tp, basic);
325 ATF_TP_ADD_TC(tp, child);
326 ATF_TP_ADD_TC(tp, timedwait);
327
328 return atf_no_error();
329 }
330