#include <sys/cdefs.h>
__COPYRIGHT("@(#) Copyright (c) 2008\
The NetBSD Foundation, inc. All rights reserved.");
__RCSID("$NetBSD: t_once.c,v 1.3 2025/03/30 23:03:06 riastradh Exp $");
#include <sys/time.h>
#include <sys/wait.h>
#include <pthread.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <atf-c.h>
#include "h_common.h"
#include "h_macros.h"
static pthread_once_t once = PTHREAD_ONCE_INIT;
static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
static int x;
#define NTHREADS 25
static void
ofunc(void)
{
printf("Variable x has value %d\n", x);
x++;
}
static void
ofunc_silent(void)
{
x++;
}
ATF_TC(once1);
ATF_TC_HEAD(once1, tc)
{
atf_tc_set_md_var(tc, "descr", "Checks pthread_once()");
}
ATF_TC_BODY(once1, tc)
{
printf("1: Test 1 of pthread_once()\n");
PTHREAD_REQUIRE(pthread_once(&once, ofunc));
PTHREAD_REQUIRE(pthread_once(&once, ofunc));
printf("1: X has value %d\n",x );
ATF_REQUIRE_EQ(x, 1);
}
static void
once2_ofunc(void)
{
x++;
printf("ofunc: Variable x has value %d\n", x);
x++;
}
static void *
once2_threadfunc(void *arg)
{
int num;
PTHREAD_REQUIRE(pthread_once(&once, once2_ofunc));
num = *(int *)arg;
printf("Thread %d sees x with value %d\n", num, x);
ATF_REQUIRE_EQ(x, 2);
return NULL;
}
ATF_TC(once2);
ATF_TC_HEAD(once2, tc)
{
atf_tc_set_md_var(tc, "descr", "Checks pthread_once()");
}
ATF_TC_BODY(once2, tc)
{
pthread_t threads[NTHREADS];
int id[NTHREADS];
int i;
printf("1: Test 2 of pthread_once()\n");
for (i=0; i < NTHREADS; i++) {
id[i] = i;
PTHREAD_REQUIRE(pthread_create(&threads[i], NULL, once2_threadfunc, &id[i]));
}
for (i=0; i < NTHREADS; i++)
PTHREAD_REQUIRE(pthread_join(threads[i], NULL));
printf("1: X has value %d\n",x );
ATF_REQUIRE_EQ(x, 2);
}
static void
once3_cleanup(void *m)
{
pthread_mutex_t *mu = m;
PTHREAD_REQUIRE(pthread_mutex_unlock(mu));
}
static void
once3_ofunc(void)
{
pthread_testcancel();
}
static void *
once3_threadfunc(void *arg)
{
PTHREAD_REQUIRE(pthread_mutex_lock(&mutex));
pthread_cleanup_push(once3_cleanup, &mutex);
PTHREAD_REQUIRE(pthread_once(&once, once3_ofunc));
pthread_cleanup_pop(1);
return NULL;
}
static void
handler(int sig, siginfo_t *info, void *ctx)
{
atf_tc_fail("Signal handler was called; "
"main thread deadlocked in pthread_once()");
}
ATF_TC(once3);
ATF_TC_HEAD(once3, tc)
{
atf_tc_set_md_var(tc, "descr", "Checks pthread_once()");
}
ATF_TC_BODY(once3, tc)
{
pthread_t thread;
struct sigaction act;
struct itimerval it;
printf("Test 3 of pthread_once() (test versus cancellation)\n");
act.sa_sigaction = handler;
sigemptyset(&act.sa_mask);
act.sa_flags = SA_SIGINFO;
sigaction(SIGALRM, &act, NULL);
timerclear(&it.it_value);
it.it_value.tv_usec = 500000;
timerclear(&it.it_interval);
setitimer(ITIMER_REAL, &it, NULL);
PTHREAD_REQUIRE(pthread_mutex_lock(&mutex));
PTHREAD_REQUIRE(pthread_create(&thread, NULL, once3_threadfunc, NULL));
PTHREAD_REQUIRE(pthread_cancel(thread));
PTHREAD_REQUIRE(pthread_mutex_unlock(&mutex));
PTHREAD_REQUIRE(pthread_join(thread, NULL));
PTHREAD_REQUIRE(pthread_once(&once, ofunc));
timerclear(&it.it_value);
setitimer(ITIMER_REAL, &it, NULL);
printf("Test succeeded\n");
}
static long trial;
static void *
fork_and_once(void *cookie)
{
pthread_barrier_t *bar = cookie;
pid_t pid, child;
int status;
(void)pthread_barrier_wait(bar);
RL(pid = fork());
if (pid == 0) {
(void)alarm(1);
(void)pthread_once(&once, &ofunc_silent);
_exit(x - 1);
}
RL(child = waitpid(pid, &status, 0));
ATF_REQUIRE_EQ_MSG(child, pid, "child=%lld pid=%lld",
(long long)child, (long long)pid);
ATF_REQUIRE_MSG(!WIFSIGNALED(status),
"child exited on signal %d (%s) in trial %ld",
WTERMSIG(status), strsignal(WTERMSIG(status)), trial);
ATF_REQUIRE_MSG(WIFEXITED(status) && WEXITSTATUS(status) == 0,
"child exited 0x%x in trial %ld", status, trial);
return NULL;
}
ATF_TC(oncefork);
ATF_TC_HEAD(oncefork, tc)
{
atf_tc_set_md_var(tc, "descr", "Test racing pthread_once with fork");
}
ATF_TC_BODY(oncefork, tc)
{
static pthread_once_t once0 = PTHREAD_ONCE_INIT;
pthread_barrier_t bar;
long ntrials = atf_tc_get_config_var_as_long_wd(tc,
"pthread_once_forktrials", 0);
if (ntrials <= 0) {
atf_tc_skip("pthread_once takes thousands of fork trials"
" on a multicore system to detect a race; set"
" pthread_once_forktrials to the number of trials to"
" enable this test");
}
RZ(pthread_barrier_init(&bar, NULL, 2));
for (trial = 0; trial < ntrials; trial++) {
pthread_t t;
once = once0;
x = 0;
RZ(pthread_create(&t, NULL, &fork_and_once, &bar));
(void)alarm(1);
(void)pthread_barrier_wait(&bar);
(void)pthread_once(&once, &ofunc_silent);
(void)alarm(0);
RZ(pthread_join(t, NULL));
}
}
ATF_TP_ADD_TCS(tp)
{
ATF_TP_ADD_TC(tp, once1);
ATF_TP_ADD_TC(tp, once2);
ATF_TP_ADD_TC(tp, once3);
ATF_TP_ADD_TC(tp, oncefork);
return atf_no_error();
}