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/* This testcase is part of GDB, the GNU debugger.
Copyright 2022-2023 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <pthread.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <errno.h>
#include <assert.h>
#include <limits.h>
/* Number of threads doing forks. */
#define N_FORKERS 4
static void *
forker (void *arg)
{
for (;;)
{
pid_t pid = FORK_FUNC ();
if (pid == 0)
_exit (11);
assert (pid > 0);
/* Wait for children to exit. */
int ret;
int stat;
do
{
ret = waitpid (pid, &stat, 0);
} while (ret == -1 && errno == EINTR);
assert (ret == pid);
assert (WIFEXITED (stat));
assert (WEXITSTATUS (stat) == 11);
/* We need a sleep, otherwise the forking threads spam events and the
stepping thread doesn't make progress. Sleep for a bit less than
`sleep_a_bit` does, so that forks are likely to interrupt a "next". */
usleep (40 * 1000);
}
return NULL;
}
static void
sleep_a_bit (void)
{
usleep (1000 * 50);
}
int
main (void)
{
int i;
alarm (60);
pthread_t thread[N_FORKERS];
for (i = 0; i < N_FORKERS; ++i)
{
int ret = pthread_create (&thread[i], NULL, forker, NULL);
assert (ret == 0);
}
for (i = 0; i < INT_MAX; ++i) /* for loop */
{
sleep_a_bit (); /* break here */
sleep_a_bit (); /* other line */
}
for (i = 0; i < N_FORKERS; ++i)
pthread_join (thread[i], NULL);
return 0;
}
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