/*      $OpenBSD: sig-stop3.c,v 1.2 2025/09/16 09:35:39 jsg Exp $       */
/*
 *      Written by Artur Grabowski <art@openbsd.org> 2007 Public Domain.
 *      Written by Claudio Jeker <claudio@openbsd.org> 2024 Public Domain.
 */
#include <sys/types.h>
#include <sys/time.h>
#include <sys/wait.h>

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <time.h>
#include <err.h>
#include <signal.h>
#include <pthread.h>

#define THREAD_COUNT    4

volatile sig_atomic_t tstp_count, cont_count;
pid_t child;

static void
alrm_handler(int sig)
{
        kill(child, SIGKILL);
        dprintf(STDERR_FILENO, "timeout\n");
        _exit(2);
}


static void *
thread(void *arg)
{
        struct timespec ts = { .tv_sec = 2 };

        while (nanosleep(&ts, &ts) != 0)
                ;

        return NULL;
}

static int
child_main(void)
{
        pthread_t self, pthread[THREAD_COUNT];
        sigset_t set;
        int i, r;

        for (i = 0; i < THREAD_COUNT; i++) {
                if ((r = pthread_create(&pthread[i], NULL, thread, NULL))) {
                        warnc(r, "could not create thread");
                        pthread[i] = self;
                }
        }

        /* terminate main process */
        pthread_exit(NULL);
}

int
main(int argc, char **argv)
{
        struct timespec ts = { .tv_nsec = 200 * 1000 * 1000 };
        int status;

        switch((child = fork())) {
        case -1:
                err(1, "fork");
        case 0:
                exit(child_main());
        default:
                break;
        }

        signal(SIGALRM, alrm_handler);
        alarm(5);

        nanosleep(&ts, NULL);

        printf("sending SIGSTOP\n");
        if (kill(child, SIGSTOP) == -1)
                err(1, "kill");

        printf("waiting...\n");
        if (waitpid(child, &status, WCONTINUED|WUNTRACED) <= 0)
                err(1, "waitpid");

        if (!WIFSTOPPED(status))
                errx(1, "bad status, not stopped: %d", status);
        printf("got stopped notification\n");

        nanosleep(&ts, NULL);

        printf("killing child\n");
        if (kill(child, SIGKILL) == -1)
                err(1, "kill");

        if (waitpid(child, &status, 0) <= 0)
                err(1, "waitpid");

        if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGKILL)
                errx(1, "bad status: %d", status);

        printf("OK\n");
        return 0;
}