/*      $OpenBSD: earlysig.c,v 1.2 2014/05/20 01:25:24 guenther Exp $   */

/*
 * Public domain.  2005, Otto Moerbeek; 2013, Philip Guenther
 *
 * Try to create the case where a signal is delivered to a process before
 * the pthread fork() wrapper can unlock the ld.so bind lock.
 */

#include <sys/types.h>
#include <sys/time.h>
#include <sys/utsname.h>
#include <sys/wait.h>

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

void dohup(int signo)
{
        struct utsname name;
        uname(&name);                   /* anything that'll require binding */
}

void *tmain(void *arg)
{
        return (arg);
}

int
main()
{
        pthread_t tid;
        pid_t pid, rpid;
        int r, status;

        if (signal(SIGHUP, dohup) == SIG_ERR)
                err(1, "signal");

        /* make sure the thread library is fully active */
        if ((r = pthread_create(&tid, NULL, tmain, NULL)))
                errc(1, r, "pthread_create");
        pthread_join(tid, NULL);

        /* make sure kill() and all the symbols in fork() are bound */
        kill(0, 0);
        if ((pid = fork()) <= 0) {
                if (pid == -1)
                        err(1, "fork");
                _exit(0);
        }
        if (waitpid(pid, &status, 0) == -1)
                err(1, "waitpid");


        switch(pid = fork()) {
        case -1:
                err(1, "fork");
                break;
        case 0:
                sleep(2);
                _exit(0);
        default:
                kill(pid, SIGHUP);
                sleep(3);
                if ((rpid = waitpid(pid, &status, WNOHANG)) == -1)
                        err(1, "waitpid");
                if (rpid == 0) {
                        /* took too long */
                        kill(pid, SIGKILL);
                        if (waitpid(pid, &status, 0) == -1)
                                err(1, "waitpid");
                }
                if (WIFEXITED(status) && WEXITSTATUS(status) == 0)
                        exit(0);
                else if (WIFEXITED(status))
                        errx(1, "child exited with status %d",
                            WEXITSTATUS(status));
                else if (WTERMSIG(status) == SIGKILL)
                        errx(1, "failed: child hung");
                errx(1, "child killed by signal %d", WTERMSIG(status));
        }
}