Dir.empty?

static VALUE
rb_dir_s_empty_p(VALUE obj, VALUE dirname)
{
    VALUE result, orig;
    const char *path;
    enum {false_on_notdir = 1};

    FilePathValue(dirname);
    orig = rb_str_dup_frozen(dirname);
    dirname = rb_str_encode_ospath(dirname);
    dirname = rb_str_dup_frozen(dirname);
    path = RSTRING_PTR(dirname);

#if defined HAVE_GETATTRLIST && defined ATTR_DIR_ENTRYCOUNT
    {
        u_int32_t attrbuf[SIZEUP32(fsobj_tag_t)];
        struct attrlist al = {ATTR_BIT_MAP_COUNT, 0, ATTR_CMN_OBJTAG,};
        struct getattrlist_args args = GETATTRLIST_ARGS(&al, attrbuf, 0);
        if (gvl_getattrlist(&args, path) != 0)
            rb_sys_fail_path(orig);
        if (*(const fsobj_tag_t *)(attrbuf+1) == VT_HFS) {
            al.commonattr = 0;
            al.dirattr = ATTR_DIR_ENTRYCOUNT;
            if (gvl_getattrlist(&args, path) == 0) {
                if (attrbuf[0] >= 2 * sizeof(u_int32_t))
                    return RBOOL(attrbuf[1] == 0);
                if (false_on_notdir) return Qfalse;
            }
            rb_sys_fail_path(orig);
        }
    }
#endif

    result = (VALUE)IO_WITHOUT_GVL(nogvl_dir_empty_p, (void *)path);
    if (FIXNUM_P(result)) {
        rb_syserr_fail_path((int)FIX2LONG(result), orig);
    }
    return result;
}