t_once.c revision 1.2.16.1
1 /* $NetBSD: t_once.c,v 1.2.16.1 2025/08/02 05:58:09 perseant Exp $ */ 2 3 /* 4 * Copyright (c) 2008 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 #include <sys/cdefs.h> 30 __COPYRIGHT("@(#) Copyright (c) 2008\ 31 The NetBSD Foundation, inc. All rights reserved."); 32 __RCSID("$NetBSD: t_once.c,v 1.2.16.1 2025/08/02 05:58:09 perseant Exp $"); 33 34 #include <sys/time.h> 35 #include <sys/wait.h> 36 37 #include <pthread.h> 38 #include <signal.h> 39 #include <stdio.h> 40 #include <stdlib.h> 41 #include <unistd.h> 42 43 #include <atf-c.h> 44 45 #include "h_common.h" 46 #include "h_macros.h" 47 48 static pthread_once_t once = PTHREAD_ONCE_INIT; 49 static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; 50 static int x; 51 52 #define NTHREADS 25 53 54 static void 55 ofunc(void) 56 { 57 printf("Variable x has value %d\n", x); 58 x++; 59 } 60 61 static void 62 ofunc_silent(void) 63 { 64 x++; 65 } 66 67 ATF_TC(once1); 68 ATF_TC_HEAD(once1, tc) 69 { 70 atf_tc_set_md_var(tc, "descr", "Checks pthread_once()"); 71 } 72 ATF_TC_BODY(once1, tc) 73 { 74 75 printf("1: Test 1 of pthread_once()\n"); 76 77 PTHREAD_REQUIRE(pthread_once(&once, ofunc)); 78 PTHREAD_REQUIRE(pthread_once(&once, ofunc)); 79 80 printf("1: X has value %d\n",x ); 81 ATF_REQUIRE_EQ(x, 1); 82 } 83 84 static void 85 once2_ofunc(void) 86 { 87 x++; 88 printf("ofunc: Variable x has value %d\n", x); 89 x++; 90 } 91 92 static void * 93 once2_threadfunc(void *arg) 94 { 95 int num; 96 97 PTHREAD_REQUIRE(pthread_once(&once, once2_ofunc)); 98 99 num = *(int *)arg; 100 printf("Thread %d sees x with value %d\n", num, x); 101 ATF_REQUIRE_EQ(x, 2); 102 103 return NULL; 104 } 105 106 ATF_TC(once2); 107 ATF_TC_HEAD(once2, tc) 108 { 109 atf_tc_set_md_var(tc, "descr", "Checks pthread_once()"); 110 } 111 ATF_TC_BODY(once2, tc) 112 { 113 pthread_t threads[NTHREADS]; 114 int id[NTHREADS]; 115 int i; 116 117 printf("1: Test 2 of pthread_once()\n"); 118 119 for (i=0; i < NTHREADS; i++) { 120 id[i] = i; 121 PTHREAD_REQUIRE(pthread_create(&threads[i], NULL, once2_threadfunc, &id[i])); 122 } 123 124 for (i=0; i < NTHREADS; i++) 125 PTHREAD_REQUIRE(pthread_join(threads[i], NULL)); 126 127 printf("1: X has value %d\n",x ); 128 ATF_REQUIRE_EQ(x, 2); 129 } 130 131 static void 132 once3_cleanup(void *m) 133 { 134 pthread_mutex_t *mu = m; 135 136 PTHREAD_REQUIRE(pthread_mutex_unlock(mu)); 137 } 138 139 static void 140 once3_ofunc(void) 141 { 142 pthread_testcancel(); 143 } 144 145 static void * 146 once3_threadfunc(void *arg) 147 { 148 PTHREAD_REQUIRE(pthread_mutex_lock(&mutex)); 149 pthread_cleanup_push(once3_cleanup, &mutex); 150 PTHREAD_REQUIRE(pthread_once(&once, once3_ofunc)); 151 pthread_cleanup_pop(1); 152 153 return NULL; 154 } 155 156 static void 157 handler(int sig, siginfo_t *info, void *ctx) 158 { 159 atf_tc_fail("Signal handler was called; " 160 "main thread deadlocked in pthread_once()"); 161 } 162 163 ATF_TC(once3); 164 ATF_TC_HEAD(once3, tc) 165 { 166 atf_tc_set_md_var(tc, "descr", "Checks pthread_once()"); 167 } 168 ATF_TC_BODY(once3, tc) 169 { 170 pthread_t thread; 171 struct sigaction act; 172 struct itimerval it; 173 printf("Test 3 of pthread_once() (test versus cancellation)\n"); 174 175 act.sa_sigaction = handler; 176 sigemptyset(&act.sa_mask); 177 act.sa_flags = SA_SIGINFO; 178 sigaction(SIGALRM, &act, NULL); 179 180 timerclear(&it.it_value); 181 it.it_value.tv_usec = 500000; 182 timerclear(&it.it_interval); 183 setitimer(ITIMER_REAL, &it, NULL); 184 185 PTHREAD_REQUIRE(pthread_mutex_lock(&mutex)); 186 PTHREAD_REQUIRE(pthread_create(&thread, NULL, once3_threadfunc, NULL)); 187 PTHREAD_REQUIRE(pthread_cancel(thread)); 188 PTHREAD_REQUIRE(pthread_mutex_unlock(&mutex)); 189 PTHREAD_REQUIRE(pthread_join(thread, NULL)); 190 191 PTHREAD_REQUIRE(pthread_once(&once, ofunc)); 192 193 /* Cancel timer */ 194 timerclear(&it.it_value); 195 setitimer(ITIMER_REAL, &it, NULL); 196 197 printf("Test succeeded\n"); 198 } 199 200 static long trial; 201 202 static void * 203 fork_and_once(void *cookie) 204 { 205 pthread_barrier_t *bar = cookie; 206 pid_t pid, child; 207 int status; 208 209 (void)pthread_barrier_wait(bar); 210 RL(pid = fork()); 211 if (pid == 0) { 212 (void)alarm(1); 213 (void)pthread_once(&once, &ofunc_silent); 214 _exit(x - 1); 215 } 216 RL(child = waitpid(pid, &status, 0)); 217 ATF_REQUIRE_EQ_MSG(child, pid, "child=%lld pid=%lld", 218 (long long)child, (long long)pid); 219 ATF_REQUIRE_MSG(!WIFSIGNALED(status), 220 "child exited on signal %d (%s) in trial %ld", 221 WTERMSIG(status), strsignal(WTERMSIG(status)), trial); 222 ATF_REQUIRE_MSG(WIFEXITED(status) && WEXITSTATUS(status) == 0, 223 "child exited 0x%x in trial %ld", status, trial); 224 return NULL; 225 } 226 227 ATF_TC(oncefork); 228 ATF_TC_HEAD(oncefork, tc) 229 { 230 atf_tc_set_md_var(tc, "descr", "Test racing pthread_once with fork"); 231 } 232 ATF_TC_BODY(oncefork, tc) 233 { 234 static pthread_once_t once0 = PTHREAD_ONCE_INIT; 235 pthread_barrier_t bar; 236 long ntrials = atf_tc_get_config_var_as_long_wd(tc, 237 "pthread_once_forktrials", 0); 238 239 if (ntrials <= 0) { 240 atf_tc_skip("pthread_once takes thousands of fork trials" 241 " on a multicore system to detect a race; set" 242 " pthread_once_forktrials to the number of trials to" 243 " enable this test"); 244 } 245 246 RZ(pthread_barrier_init(&bar, NULL, 2)); 247 248 for (trial = 0; trial < ntrials; trial++) { 249 pthread_t t; 250 251 once = once0; 252 x = 0; 253 254 RZ(pthread_create(&t, NULL, &fork_and_once, &bar)); 255 (void)alarm(1); 256 (void)pthread_barrier_wait(&bar); 257 (void)pthread_once(&once, &ofunc_silent); 258 (void)alarm(0); 259 RZ(pthread_join(t, NULL)); 260 } 261 } 262 263 ATF_TP_ADD_TCS(tp) 264 { 265 ATF_TP_ADD_TC(tp, once1); 266 ATF_TP_ADD_TC(tp, once2); 267 ATF_TP_ADD_TC(tp, once3); 268 ATF_TP_ADD_TC(tp, oncefork); 269 270 return atf_no_error(); 271 } 272
Indexes created Tue Sep 30 20:09:53 GMT 2025