int __mnt_table_parse_mtab(struct libmnt_table *tb, const char *filename,
			   struct libmnt_table *u_tb)
{
	int rc = 0, priv_utab = 0;
	int explicit_file = filename ? 1 : 0;

	assert(tb);

	if (filename)
		DBG(TAB, ul_debugobj(tb, "%s requested as mtab", filename));

#ifdef USE_LIBMOUNT_SUPPORT_MTAB
	if (mnt_has_regular_mtab(&filename, NULL)) {

		DBG(TAB, ul_debugobj(tb, "force mtab usage [filename=%s]", filename));

		rc = mnt_table_parse_file(tb, filename);

		/*
		 * If @filename forces us to read from /proc then also read
		 * utab file to merge userspace mount options.
		 */
		if (rc == 0 && is_mountinfo(tb))
			goto read_utab;

		if (!rc)
			return 0;
		filename = NULL;	/* failed */
	} else
		filename = NULL;	/* mtab useless */
#endif

	if (!filename || strcmp(filename, _PATH_PROC_MOUNTINFO) == 0) {
		filename = _PATH_PROC_MOUNTINFO;
		tb->fmt = MNT_FMT_MOUNTINFO;
		DBG(TAB, ul_debugobj(tb, "mtab parse: #1 read mountinfo"));
	} else
		tb->fmt = MNT_FMT_GUESS;

	rc = mnt_table_parse_file(tb, filename);
	if (rc) {
		if (explicit_file)
			return rc;

		/* hmm, old kernel? ...try /proc/mounts */
		tb->fmt = MNT_FMT_MTAB;
		return mnt_table_parse_file(tb, _PATH_PROC_MOUNTS);
	}

	if (!is_mountinfo(tb))
		return 0;
#ifdef USE_LIBMOUNT_SUPPORT_MTAB
read_utab:
#endif
	DBG(TAB, ul_debugobj(tb, "mtab parse: #2 read utab"));

	if (mnt_table_get_nents(tb) == 0)
		return 0;			/* empty, ignore utab */
	/*
	 * try to read the user specific information from /run/mount/utabs
	 */
	if (!u_tb) {
		const char *utab = mnt_get_utab_path();

		if (!utab || is_file_empty(utab))
			return 0;

		u_tb = mnt_new_table();
		if (!u_tb)
			return -ENOMEM;

		u_tb->fmt = MNT_FMT_UTAB;
		mnt_table_set_parser_fltrcb(u_tb, tb->fltrcb, tb->fltrcb_data);

		rc = mnt_table_parse_file(u_tb, utab);
		priv_utab = 1;
	}

	DBG(TAB, ul_debugobj(tb, "mtab parse: #3 merge utab"));

	if (rc == 0) {
		struct libmnt_fs *u_fs;
		struct libmnt_iter itr;

		mnt_reset_iter(&itr, MNT_ITER_BACKWARD);

		/*  merge user options into mountinfo from the kernel */
		while(mnt_table_next_fs(u_tb, &itr, &u_fs) == 0)
			mnt_table_merge_user_fs(tb, u_fs);
	}


	if (priv_utab)
		mnt_unref_table(u_tb);
	return 0;
}
int __mnt_table_parse_mtab(struct libmnt_table *tb, const char *filename,
			   struct libmnt_table *u_tb)
{
	int rc = 0, priv_utab = 0;
	int explicit_file = filename ? 1 : 0;

	assert(tb);

	if (filename)
		DBG(TAB, ul_debugobj(tb, "%s requested as mtab", filename));

#ifdef USE_LIBMOUNT_SUPPORT_MTAB
	if (mnt_has_regular_mtab(&filename, NULL)) {

		DBG(TAB, ul_debugobj(tb, "force mtab usage [filename=%s]", filename));

		rc = mnt_table_parse_file(tb, filename);

		 
		if (rc == 0 && is_mountinfo(tb))
			goto read_utab;

		if (!rc)
			return 0;
		filename = NULL;	 
	} else
		filename = NULL;	 
#endif

	if (!filename || strcmp(filename, _PATH_PROC_MOUNTINFO) == 0) {
		filename = _PATH_PROC_MOUNTINFO;
		tb->fmt = MNT_FMT_MOUNTINFO;
		DBG(TAB, ul_debugobj(tb, "mtab parse: #1 read mountinfo"));
	} else
		tb->fmt = MNT_FMT_GUESS;

	rc = mnt_table_parse_file(tb, filename);
	if (rc) {
		if (explicit_file)
			return rc;

		 
		tb->fmt = MNT_FMT_MTAB;
		return mnt_table_parse_file(tb, _PATH_PROC_MOUNTS);
	}

	if (!is_mountinfo(tb))
		return 0;
#ifdef USE_LIBMOUNT_SUPPORT_MTAB
read_utab:
#endif
	DBG(TAB, ul_debugobj(tb, "mtab parse: #2 read utab"));

	if (mnt_table_get_nents(tb) == 0)
		return 0;			 
	 
	if (!u_tb) {
		const char *utab = mnt_get_utab_path();

		if (!utab || is_file_empty(utab))
			return 0;

		u_tb = mnt_new_table();
		if (!u_tb)
			return -ENOMEM;

		u_tb->fmt = MNT_FMT_UTAB;
		mnt_table_set_parser_fltrcb(u_tb, tb->fltrcb, tb->fltrcb_data);

		rc = mnt_table_parse_file(u_tb, utab);
		priv_utab = 1;
	}

	DBG(TAB, ul_debugobj(tb, "mtab parse: #3 merge utab"));

	if (rc == 0) {
		struct libmnt_fs *u_fs;
		struct libmnt_iter itr;

		mnt_reset_iter(&itr, MNT_ITER_BACKWARD);

		 
		while(mnt_table_next_fs(u_tb, &itr, &u_fs) == 0)
			mnt_table_merge_user_fs(tb, u_fs);
	}


	if (priv_utab)
		mnt_unref_table(u_tb);
	return 0;
}