/*      $OpenBSD: realpath-chroot.c,v 1.1.1.1 2019/08/05 15:16:39 bluhm Exp $   */
/*
 * Copyright (c) 2019 Alexander Bluhm <bluhm@openbsd.org>
 * Copyright (c) 2019 Moritz Buhl <mbuhl@moritzbuhl.de>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

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

int
main(int argc, char *argv[])
{
        char *root, *dir, *path = NULL;
        char res[PATH_MAX];

        if (argc != 3)
                errx(2, "usage: realpath-chroot root dir");

        root = argv[1];
        dir = argv[2];

        if (chroot(root) == -1)
                err(1, "chroot %s", root);

        if (realpath(dir, res) == NULL)
                err(1, "realpath %s", dir);

        return 0;
}