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/* This testcase is part of GDB, the GNU debugger.
Copyright 2015-2017 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 <assert.h>
#include <pthread.h>
#include <unistd.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <stdlib.h>
#include <errno.h>
/* Number of threads. Each thread continuously spawns a fork and wait
for it. If we have another thread continuously start a step over,
gdbserver should end up finding new forks while suspending
threads. */
#define NTHREADS 10
pthread_t threads[NTHREADS];
pthread_barrier_t barrier;
#define NFORKS 10
/* Used to create a conditional breakpoint that always fails. */
volatile int zero;
static void *
thread_forks (void *arg)
{
int i;
pthread_barrier_wait (&barrier);
for (i = 0; i < NFORKS; i++)
{
pid_t pid;
do
{
pid = fork ();
}
while (pid == -1 && errno == EINTR);
if (pid > 0)
{
int status;
/* Parent. */
do
{
pid = waitpid (pid, &status, 0);
}
while (pid == -1 && errno == EINTR);
if (pid == -1)
{
perror ("wait");
exit (1);
}
if (!WIFEXITED (status))
{
printf ("Unexpected wait status 0x%x from child %d\n",
status, pid);
}
}
else if (pid == 0)
{
/* Child. */
exit (0);
}
else
{
perror ("fork");
exit (1);
}
}
}
/* Set this to tell the thread_breakpoint thread to exit. */
volatile int break_out;
static void *
thread_breakpoint (void *arg)
{
pthread_barrier_wait (&barrier);
while (!break_out)
{
usleep (1); /* set break here */
}
return NULL;
}
pthread_barrier_t barrier;
int
main (void)
{
int i;
int ret;
pthread_t bp_thread;
/* Don't run forever. */
alarm (180);
pthread_barrier_init (&barrier, NULL, NTHREADS + 1);
/* Start the threads that constantly fork. */
for (i = 0; i < NTHREADS; i++)
{
ret = pthread_create (&threads[i], NULL, thread_forks, NULL);
assert (ret == 0);
}
/* Start the thread that constantly hit a conditional breakpoint
that needs to be stepped over. */
ret = pthread_create (&bp_thread, NULL, thread_breakpoint, NULL);
assert (ret == 0);
/* Wait for forking to stop. */
for (i = 0; i < NTHREADS; i++)
{
ret = pthread_join (threads[i], NULL);
assert (ret == 0);
}
break_out = 1;
pthread_join (bp_thread, NULL);
assert (ret == 0);
return 0;
}
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