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); 82 ATF_TC_HEAD(basic, tc) 83 { 84 atf_tc_set_md_var(tc, "descr", "Checks basic functionality of POSIX " 85 "semaphores"); 86 } 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 } 117 ATF_TC_CLEANUP(basic, tc) 118 { 119 (void)sem_unlink("/sem_b"); 120 } 121 122 ATF_TC_WITH_CLEANUP(child); 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 } 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 } 178 ATF_TC_CLEANUP(child, tc) 179 { 180 (void)sem_unlink("/sem_a"); 181 } 182 183 static inline void 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 volatile sig_atomic_t got_sigalrm = 0; 194 195 static void 196 sigalrm_handler(int sig __unused) 197 { 198 got_sigalrm = 1; 199 } 200 201 ATF_TC(timedwait); 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 } 211 ATF_TC_BODY(timedwait, tc) 212 { 213 struct timespec ts; 214 sem_t sem; 215 int result; 216 217 SEM_REQUIRE(sem_init(&sem, 0, 0)); 218 SEM_REQUIRE(sem_post(&sem)); 219 ATF_REQUIRE_MSG(clock_gettime(CLOCK_REALTIME, &ts) == 0, 220 "%s", strerror(errno)); 221 timespec_add_ms(&ts, 100); 222 SEM_REQUIRE(sem_timedwait(&sem, &ts)); 223 ATF_REQUIRE_ERRNO(ETIMEDOUT, sem_timedwait(&sem, &ts)); 224 ts.tv_sec--; 225 ATF_REQUIRE_ERRNO(ETIMEDOUT, sem_timedwait(&sem, &ts)); 226 SEM_REQUIRE(sem_post(&sem)); 227 SEM_REQUIRE(sem_timedwait(&sem, &ts)); 228 229 /* timespec validation, in the past */ 230 ts.tv_nsec += 1000*1000*1000; 231 ATF_REQUIRE_ERRNO(EINVAL, sem_timedwait(&sem, &ts)); 232 ts.tv_nsec = -1; 233 ATF_REQUIRE_ERRNO(EINVAL, sem_timedwait(&sem, &ts)); 234 /* timespec validation, in the future */ 235 ATF_REQUIRE_MSG(clock_gettime(CLOCK_REALTIME, &ts) == 0, 236 "%s", strerror(errno)); 237 ts.tv_sec++; 238 ts.tv_nsec = 1000*1000*1000; 239 ATF_REQUIRE_ERRNO(EINVAL, sem_timedwait(&sem, &ts)); 240 ts.tv_nsec = -1; 241 ATF_REQUIRE_ERRNO(EINVAL, sem_timedwait(&sem, &ts)); 242 243 /* EINTR */ 244 struct sigaction act = { 245 .sa_handler = sigalrm_handler, 246 .sa_flags = 0 /* not SA_RESTART */ 247 }; 248 ATF_REQUIRE_MSG(sigemptyset(&act.sa_mask) == 0, 249 "%s", strerror(errno)); 250 ATF_REQUIRE_MSG(sigaction(SIGALRM, &act, NULL) == 0, 251 "%s", strerror(errno)); 252 struct itimerval it = { 253 .it_value.tv_usec = 50*1000 254 }; 255 ATF_REQUIRE_MSG(setitimer(ITIMER_REAL, &it, NULL) == 0, 256 "%s", strerror(errno)); 257 ATF_REQUIRE_MSG(clock_gettime(CLOCK_REALTIME, &ts) == 0, 258 "%s", strerror(errno)); 259 timespec_add_ms(&ts, 100); 260 ATF_REQUIRE_ERRNO(EINTR, sem_timedwait(&sem, &ts)); 261 ATF_REQUIRE_MSG(got_sigalrm, "did not get SIGALRM"); 262 263 #ifdef __FreeBSD__ 264 /* CLOCK_MONOTONIC, absolute */ 265 SEM_REQUIRE(sem_post(&sem)); 266 ATF_REQUIRE_MSG(clock_gettime(CLOCK_MONOTONIC, &ts) == 0, 267 "%s", strerror(errno)); 268 timespec_add_ms(&ts, 100); 269 SEM_REQUIRE(sem_clockwait_np(&sem, CLOCK_MONOTONIC, TIMER_ABSTIME, 270 &ts, NULL)); 271 ATF_REQUIRE_ERRNO(ETIMEDOUT, 272 sem_clockwait_np(&sem, CLOCK_MONOTONIC, TIMER_ABSTIME, &ts, NULL)); 273 274 /* CLOCK_MONOTONIC, relative */ 275 SEM_REQUIRE(sem_post(&sem)); 276 ts.tv_sec = 0; 277 ts.tv_nsec = 100*1000*1000; 278 SEM_REQUIRE(sem_clockwait_np(&sem, CLOCK_MONOTONIC, 0, 279 &ts, NULL)); 280 ATF_REQUIRE_ERRNO(ETIMEDOUT, 281 sem_clockwait_np(&sem, CLOCK_MONOTONIC, 0, &ts, NULL)); 282 283 /* absolute does not update remaining time on EINTR */ 284 struct timespec remain = {42, 1000*1000*1000}; 285 got_sigalrm = 0; 286 it.it_value.tv_usec = 50*1000; 287 ATF_REQUIRE_MSG(setitimer(ITIMER_REAL, &it, NULL) == 0, 288 "%s", strerror(errno)); 289 ATF_REQUIRE_MSG(clock_gettime(CLOCK_MONOTONIC, &ts) == 0, 290 "%s", strerror(errno)); 291 timespec_add_ms(&ts, 100); 292 ATF_REQUIRE_ERRNO(EINTR, sem_clockwait_np(&sem, CLOCK_MONOTONIC, 293 TIMER_ABSTIME, &ts, &remain)); 294 ATF_REQUIRE_MSG(got_sigalrm, "did not get SIGALRM"); 295 ATF_REQUIRE_MSG(remain.tv_sec == 42 && remain.tv_nsec == 1000*1000*1000, 296 "an absolute clockwait modified the remaining time on EINTR"); 297 298 /* relative updates remaining time on EINTR */ 299 remain.tv_sec = 42; 300 remain.tv_nsec = 1000*1000*1000; 301 got_sigalrm = 0; 302 it.it_value.tv_usec = 50*1000; 303 ATF_REQUIRE_MSG(setitimer(ITIMER_REAL, &it, NULL) == 0, 304 "%s", strerror(errno)); 305 ts.tv_sec = 0; 306 ts.tv_nsec = 100*1000*1000; 307 ATF_REQUIRE_ERRNO(EINTR, sem_clockwait_np(&sem, CLOCK_MONOTONIC, 0, &ts, 308 &remain)); 309 ATF_REQUIRE_MSG(got_sigalrm, "did not get SIGALRM"); 310 /* 311 * If this nsec comparison turns out to be unreliable due to timing, 312 * it could simply check that nsec < 100 ms. 313 */ 314 ATF_REQUIRE_MSG(remain.tv_sec == 0 && 315 remain.tv_nsec >= 25*1000*1000 && 316 remain.tv_nsec <= 75*1000*1000, 317 "the remaining time was not as expected when a relative clockwait" 318 " got EINTR" ); 319 #endif 320 } 321 322 ATF_TP_ADD_TCS(tp) 323 { 324 325 ATF_TP_ADD_TC(tp, basic); 326 ATF_TP_ADD_TC(tp, child); 327 ATF_TP_ADD_TC(tp, timedwait); 328 329 return atf_no_error(); 330 } 331