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/* pthread_atfork supports handlers that call pthread_atfork or dlclose.
Copyright (C) 2022-2024 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <support/xdlfcn.h>
#include <stdio.h>
#include <support/xthread.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <support/xunistd.h>
#include <support/check.h>
#include <stdlib.h>
static void *
thread_func (void *x)
{
return NULL;
}
static unsigned int second_atfork_handler_runcount = 0;
static void
second_atfork_handler (void)
{
second_atfork_handler_runcount++;
}
static void *h = NULL;
static unsigned int atfork_handler_runcount = 0;
static void
prepare (void)
{
/* These atfork handlers are registered while atfork handlers are being
executed and thus will not be executed during the corresponding
fork. */
TEST_VERIFY_EXIT (pthread_atfork (second_atfork_handler,
second_atfork_handler,
second_atfork_handler) == 0);
/* This will de-register the atfork handlers registered by the dlopen'd
library and so they will not be executed. */
if (h != NULL)
{
xdlclose (h);
h = NULL;
}
atfork_handler_runcount++;
}
static void
after (void)
{
atfork_handler_runcount++;
}
static int
do_test (void)
{
/* Make sure __libc_single_threaded is 0. */
pthread_attr_t attr;
xpthread_attr_init (&attr);
xpthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
xpthread_create (&attr, thread_func, NULL);
void (*reg_atfork_handlers) (void);
h = xdlopen ("tst-atfork4mod.so", RTLD_LAZY);
reg_atfork_handlers = xdlsym (h, "reg_atfork_handlers");
reg_atfork_handlers ();
/* We register our atfork handlers *after* loading the module so that our
prepare handler is called first at fork, where we then dlclose the
module before its prepare handler has a chance to be called. */
TEST_VERIFY_EXIT (pthread_atfork (prepare, after, after) == 0);
pid_t pid = xfork ();
/* Both the parent and the child processes should observe this. */
TEST_VERIFY_EXIT (atfork_handler_runcount == 2);
TEST_VERIFY_EXIT (second_atfork_handler_runcount == 0);
if (pid > 0)
{
int childstat;
xwaitpid (-1, &childstat, 0);
TEST_VERIFY_EXIT (WIFEXITED (childstat)
&& WEXITSTATUS (childstat) == 0);
/* This time, the second set of atfork handlers should also be called
since the handlers are already in place before fork is called. */
pid = xfork ();
TEST_VERIFY_EXIT (atfork_handler_runcount == 4);
TEST_VERIFY_EXIT (second_atfork_handler_runcount == 2);
if (pid > 0)
{
xwaitpid (-1, &childstat, 0);
TEST_VERIFY_EXIT (WIFEXITED (childstat)
&& WEXITSTATUS (childstat) == 0);
}
}
return 0;
}
#include <support/test-driver.c>
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