#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>

#include <arpa/inet.h>
#include <netinet/in.h>

#include <err.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#define CHECKFD_CMD     "checkfd"
#define CHECKFD_PATH    "/usr/local/bin/" CHECKFD_CMD

int
main(void)
{
        pid_t pid;
        int s, status, ecode;

        s = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0);
        if (s < 0)
                err(1, "socket failed");

        pid = fork();
        if (pid < 0) {
                err(1, "fork failed");
        } else if (pid == 0) {
                char fd[8];

                snprintf(fd, sizeof(fd), "%d", s);
                if (execl(CHECKFD_PATH, CHECKFD_CMD, fd, NULL) < 0)
                        err(3, "execl failed");
        }

        if (waitpid(pid, &status, 0) < 0)
                err(1, "waitpid failed");

        if (!WIFEXITED(status))
                errx(1, CHECKFD_CMD " did not exit");

        ecode = WEXITSTATUS(status);
        if (ecode != 0) {
                warnx("exit code %d", ecode);
                abort();
        }

        fprintf(stderr, "passed\n");
        exit(0);
}