t_sem.c revision 1.5
1/* $NetBSD: t_sem.c,v 1.5 2020/05/14 08:34:19 msaitoh Exp $ */ 2 3/* 4 * Copyright (c) 2008, 2010, 2019 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, 2019\ 60 The NetBSD Foundation, inc. All rights reserved."); 61__RCSID("$NetBSD: t_sem.c,v 1.5 2020/05/14 08:34:19 msaitoh Exp $"); 62 63#include <sys/mman.h> 64#include <sys/wait.h> 65 66#include <errno.h> 67#include <fcntl.h> 68#include <semaphore.h> 69#include <stdio.h> 70#include <unistd.h> 71 72#include <atf-c.h> 73 74#define NCHILDREN 10 75 76ATF_TC_WITH_CLEANUP(basic); 77ATF_TC_HEAD(basic, tc) 78{ 79 atf_tc_set_md_var(tc, "descr", "Checks basic functionality of POSIX " 80 "semaphores"); 81} 82ATF_TC_BODY(basic, tc) 83{ 84 int val; 85 sem_t *sem_b; 86 87 if (sysconf(_SC_SEMAPHORES) == -1) 88 atf_tc_skip("POSIX semaphores not supported"); 89 90 sem_b = sem_open("/sem_b", O_CREAT | O_EXCL, 0644, 0); 91 ATF_REQUIRE(sem_b != SEM_FAILED); 92 93 ATF_REQUIRE_EQ(sem_getvalue(sem_b, &val), 0); 94 ATF_REQUIRE_EQ(val, 0); 95 96 ATF_REQUIRE_EQ(sem_post(sem_b), 0); 97 ATF_REQUIRE_EQ(sem_getvalue(sem_b, &val), 0); 98 ATF_REQUIRE_EQ(val, 1); 99 100 ATF_REQUIRE_EQ(sem_wait(sem_b), 0); 101 ATF_REQUIRE_EQ(sem_trywait(sem_b), -1); 102 ATF_REQUIRE_EQ(errno, EAGAIN); 103 ATF_REQUIRE_EQ(sem_post(sem_b), 0); 104 ATF_REQUIRE_EQ(sem_trywait(sem_b), 0); 105 ATF_REQUIRE_EQ(sem_post(sem_b), 0); 106 ATF_REQUIRE_EQ(sem_wait(sem_b), 0); 107 ATF_REQUIRE_EQ(sem_post(sem_b), 0); 108 109 ATF_REQUIRE_EQ(sem_close(sem_b), 0); 110 ATF_REQUIRE_EQ(sem_unlink("/sem_b"), 0); 111} 112ATF_TC_CLEANUP(basic, tc) 113{ 114 (void)sem_unlink("/sem_b"); 115} 116 117ATF_TC_WITH_CLEANUP(child); 118ATF_TC_HEAD(child, tc) 119{ 120 atf_tc_set_md_var(tc, "descr", "Checks using semaphores to synchronize " 121 "parent with multiple child processes"); 122} 123ATF_TC_BODY(child, tc) 124{ 125 pid_t children[NCHILDREN]; 126 unsigned i, j; 127 sem_t *sem_a; 128 int status; 129 130 pid_t pid; 131 132 if (sysconf(_SC_SEMAPHORES) == -1) 133 atf_tc_skip("POSIX semaphores not supported"); 134 135 sem_a = sem_open("/sem_a", O_CREAT | O_EXCL, 0644, 0); 136 ATF_REQUIRE(sem_a != SEM_FAILED); 137 138 for (j = 1; j <= 2; j++) { 139 for (i = 0; i < NCHILDREN; i++) { 140 switch ((pid = fork())) { 141 case -1: 142 atf_tc_fail("fork() returned -1"); 143 case 0: 144 printf("PID %d waiting for semaphore...\n", 145 getpid()); 146 ATF_REQUIRE_MSG(sem_wait(sem_a) == 0, 147 "sem_wait failed; iteration %d", j); 148 printf("PID %d got semaphore\n", getpid()); 149 _exit(0); 150 default: 151 children[i] = pid; 152 break; 153 } 154 } 155 156 for (i = 0; i < NCHILDREN; i++) { 157 sleep(1); 158 printf("main loop %d: posting...\n", j); 159 ATF_REQUIRE_EQ(sem_post(sem_a), 0); 160 } 161 162 for (i = 0; i < NCHILDREN; i++) { 163 ATF_REQUIRE_EQ(waitpid(children[i], &status, 0), children[i]); 164 ATF_REQUIRE(WIFEXITED(status)); 165 ATF_REQUIRE_EQ(WEXITSTATUS(status), 0); 166 } 167 } 168 169 ATF_REQUIRE_EQ(sem_close(sem_a), 0); 170 ATF_REQUIRE_EQ(sem_unlink("/sem_a"), 0); 171} 172ATF_TC_CLEANUP(child, tc) 173{ 174 (void)sem_unlink("/sem_a"); 175} 176 177ATF_TC_WITH_CLEANUP(pshared); 178ATF_TC_HEAD(pshared, tc) 179{ 180 atf_tc_set_md_var(tc, "descr", "Checks using pshared unnamed " 181 "semaphores to synchronize a master with multiple slave processes"); 182} 183 184struct shared_region { 185 sem_t the_sem; 186}; 187 188static struct shared_region * 189get_shared_region(int o_flags) 190{ 191 192 int fd = shm_open("/shm_semtest_a", o_flags, 0644); 193 ATF_REQUIRE(fd != -1); 194 195 ATF_REQUIRE_EQ(ftruncate(fd, sizeof(struct shared_region)), 0); 196 197 void *rv = mmap(NULL, sizeof(struct shared_region), 198 PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); 199 ATF_REQUIRE(rv != MAP_FAILED); 200 201 (void)close(fd); 202 203 return rv; 204} 205 206static void 207put_shared_region(struct shared_region *r) 208{ 209 ATF_REQUIRE_EQ(munmap(r, sizeof(struct shared_region)), 0); 210} 211 212ATF_TC_BODY(pshared, tc) 213{ 214 struct shared_region *master_region, *slave_region; 215 216 if (sysconf(_SC_SEMAPHORES) == -1) 217 atf_tc_skip("POSIX semaphores not supported"); 218 219 /* 220 * Create a shared memory region to contain the pshared 221 * semaphore, create the semaphore there, and then detach 222 * from the shared memory region to ensure that our child 223 * processes will be getting at it from scratch. 224 */ 225 master_region = get_shared_region(O_RDWR | O_CREAT | O_EXCL); 226 ATF_REQUIRE(sem_init(&master_region->the_sem, 1, 0) == 0); 227 put_shared_region(master_region); 228 229 /* 230 * Now execute a test that's essentially equivalent to the 231 * "child" test above, but using the pshared semaphore in the 232 * shared memory region. 233 */ 234 235 pid_t pid, children[NCHILDREN]; 236 unsigned i, j; 237 int status; 238 239 for (j = 1; j <= 2; j++) { 240 for (i = 0; i < NCHILDREN; i++) { 241 switch ((pid = fork())) { 242 case -1: 243 atf_tc_fail("fork() returned -1"); 244 case 0: 245 slave_region = get_shared_region(O_RDWR); 246 printf("PID %d waiting for semaphore...\n", 247 getpid()); 248 ATF_REQUIRE_MSG(sem_wait(&slave_region->the_sem) 249 == 0, 250 "sem_wait failed; iteration %d", j); 251 printf("PID %d got semaphore\n", getpid()); 252 _exit(0); 253 default: 254 children[i] = pid; 255 break; 256 } 257 } 258 259 master_region = get_shared_region(O_RDWR); 260 261 for (i = 0; i < NCHILDREN; i++) { 262 sleep(1); 263 printf("main loop %d: posting...\n", j); 264 ATF_REQUIRE_EQ(sem_post(&master_region->the_sem), 0); 265 } 266 267 put_shared_region(master_region); 268 269 for (i = 0; i < NCHILDREN; i++) { 270 ATF_REQUIRE_EQ(waitpid(children[i], &status, 0), children[i]); 271 ATF_REQUIRE(WIFEXITED(status)); 272 ATF_REQUIRE_EQ(WEXITSTATUS(status), 0); 273 } 274 } 275 276 master_region = get_shared_region(O_RDWR); 277 ATF_REQUIRE_EQ(sem_destroy(&master_region->the_sem), 0); 278 put_shared_region(master_region); 279 280 ATF_REQUIRE_EQ(shm_unlink("/shm_semtest_a"), 0); 281} 282ATF_TC_CLEANUP(pshared, tc) 283{ 284 /* 285 * The kernel will g/c the pshared semaphore when the process that 286 * created it exits, so no need to include that in the cleanup here. 287 */ 288 (void)shm_unlink("/shm_semtest_a"); 289} 290 291ATF_TC_WITH_CLEANUP(invalid_ops); 292ATF_TC_HEAD(invalid_ops, tc) 293{ 294 atf_tc_set_md_var(tc, "descr", "Validates behavior when calling " 295 "bad operations for the semaphore type"); 296} 297ATF_TC_BODY(invalid_ops, tc) 298{ 299 sem_t *sem; 300 sem_t the_sem; 301 302 sem = sem_open("/sem_c", O_CREAT | O_EXCL, 0644, 0); 303 ATF_REQUIRE(sem != SEM_FAILED); 304 ATF_REQUIRE(sem_destroy(sem) == -1 && errno == EINVAL); 305 ATF_REQUIRE_EQ(sem_close(sem), 0); 306 307 ATF_REQUIRE_EQ(sem_init(&the_sem, 0, 0), 0); 308 ATF_REQUIRE(sem_close(&the_sem) == -1 && errno == EINVAL); 309 ATF_REQUIRE_EQ(sem_destroy(&the_sem), 0); 310} 311ATF_TC_CLEANUP(invalid_ops, tc) 312{ 313 (void)sem_unlink("/sem_c"); 314} 315 316ATF_TP_ADD_TCS(tp) 317{ 318 319 ATF_TP_ADD_TC(tp, basic); 320 ATF_TP_ADD_TC(tp, child); 321 ATF_TP_ADD_TC(tp, pshared); 322 ATF_TP_ADD_TC(tp, invalid_ops); 323 324 return atf_no_error(); 325} 326