Adding upstream version 2.39.3.upstream/2.39.3

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3455 insertions, 0 deletions

diff --git a/libmount/src/context.c b/libmount/src/context.c
new file mode 100644
index 0000000..0cd3201
--- /dev/null
+++ b/libmount/src/context.c
@@ -0,0 +1,3455 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * This file is part of libmount from util-linux project.
+ *
+ * Copyright (C) 2010-2018 Karel Zak <kzak@redhat.com>
+ *
+ * libmount is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ */
+
+/**
+ * SECTION: context
+ * @title: Library high-level context
+ * @short_description: high-level API to mount/umount devices.
+ *
+ * <informalexample>
+ *   <programlisting>
+ *	struct libmnt_context *cxt = mnt_new_context();
+ *
+ *	mnt_context_set_options(cxt, "aaa,bbb,ccc=CCC");
+ *	mnt_context_set_mflags(cxt, MS_NOATIME|MS_NOEXEC);
+ *	mnt_context_set_target(cxt, "/mnt/foo");
+ *
+ *	if (!mnt_context_mount(cxt))
+ *		printf("successfully mounted\n");
+ *	mnt_free_context(cxt);
+ *
+ *   </programlisting>
+ * </informalexample>
+ *
+ * This code is similar to:
+ *
+ *   mount -o aaa,bbb,ccc=CCC,noatime,noexec /mnt/foo
+ *
+ */
+
+#include "mountP.h"
+#include "strutils.h"
+#include "namespace.h"
+#include "match.h"
+
+#include <sys/wait.h>
+
+/**
+ * mnt_new_context:
+ *
+ * Returns: newly allocated mount context
+ */
+struct libmnt_context *mnt_new_context(void)
+{
+	struct libmnt_context *cxt;
+	uid_t ruid, euid;
+
+	cxt = calloc(1, sizeof(*cxt));
+	if (!cxt)
+		return NULL;
+
+	ruid = getuid();
+	euid = geteuid();
+
+	mnt_context_reset_status(cxt);
+
+	cxt->ns_orig.fd = -1;
+	cxt->ns_tgt.fd = -1;
+	cxt->ns_cur = &cxt->ns_orig;
+
+	cxt->map_linux = mnt_get_builtin_optmap(MNT_LINUX_MAP);
+	cxt->map_userspace = mnt_get_builtin_optmap(MNT_USERSPACE_MAP);
+
+	INIT_LIST_HEAD(&cxt->hooksets_hooks);
+	INIT_LIST_HEAD(&cxt->hooksets_datas);
+
+	/* if we're really root and aren't running setuid */
+	cxt->restricted = (uid_t) 0 == ruid && ruid == euid ? 0 : 1;
+
+	cxt->noautofs = 0;
+
+	DBG(CXT, ul_debugobj(cxt, "----> allocate %s",
+				cxt->restricted ? "[RESTRICTED]" : ""));
+
+	return cxt;
+}
+
+/**
+ * mnt_free_context:
+ * @cxt: mount context
+ *
+ * Deallocates context struct.
+ */
+void mnt_free_context(struct libmnt_context *cxt)
+{
+	if (!cxt)
+		return;
+
+	mnt_reset_context(cxt);
+
+	free(cxt->fstype_pattern);
+	free(cxt->optstr_pattern);
+	free(cxt->tgt_prefix);
+
+	mnt_unref_table(cxt->fstab);
+	mnt_unref_cache(cxt->cache);
+	mnt_unref_fs(cxt->fs);
+
+	mnt_unref_optlist(cxt->optlist_saved);
+	mnt_unref_optlist(cxt->optlist);
+
+	mnt_free_lock(cxt->lock);
+	mnt_free_update(cxt->update);
+
+	mnt_context_set_target_ns(cxt, NULL);
+
+	free(cxt->children);
+
+	DBG(CXT, ul_debugobj(cxt, "free"));
+	free(cxt);
+}
+
+/**
+ * mnt_reset_context:
+ * @cxt: mount context
+ *
+ * Resets all information in the context that is directly related to
+ * the latest mount (spec, source, target, mount options, ...).
+ *
+ * The match patterns, target namespace, prefix, cached fstab, cached canonicalized
+ * paths and tags and [e]uid are not reset. You have to use
+ *
+ *	mnt_context_set_fstab(cxt, NULL);
+ *	mnt_context_set_cache(cxt, NULL);
+ *	mnt_context_set_fstype_pattern(cxt, NULL);
+ *	mnt_context_set_options_pattern(cxt, NULL);
+ *	mnt_context_set_target_ns(cxt, NULL);
+ *
+ * to reset this stuff.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_reset_context(struct libmnt_context *cxt)
+{
+	int fl;
+
+	if (!cxt)
+		return -EINVAL;
+
+	DBG(CXT, ul_debugobj(cxt, "<---- reset [status=%d] ---->",
+				mnt_context_get_status(cxt)));
+
+	fl = cxt->flags;
+
+	mnt_unref_fs(cxt->fs);
+	mnt_unref_table(cxt->mountinfo);
+	mnt_unref_table(cxt->utab);
+	mnt_unref_optlist(cxt->optlist);
+
+	free(cxt->helper);
+
+	cxt->fs = NULL;
+	cxt->mountinfo = NULL;
+	cxt->optlist = NULL;
+	cxt->utab = NULL;
+	cxt->helper = NULL;
+	cxt->mountdata = NULL;
+	cxt->flags = MNT_FL_DEFAULT;
+	cxt->noautofs = 0;
+	cxt->has_selinux_opt = 0;
+
+	cxt->map_linux = mnt_get_builtin_optmap(MNT_LINUX_MAP);
+	cxt->map_userspace = mnt_get_builtin_optmap(MNT_USERSPACE_MAP);
+
+	mnt_context_reset_status(cxt);
+	mnt_context_deinit_hooksets(cxt);
+
+	if (cxt->table_fltrcb)
+		mnt_context_set_tabfilter(cxt, NULL, NULL);
+
+	/* restore non-resettable flags */
+	cxt->flags |= (fl & MNT_FL_NOMTAB);
+	cxt->flags |= (fl & MNT_FL_FAKE);
+	cxt->flags |= (fl & MNT_FL_SLOPPY);
+	cxt->flags |= (fl & MNT_FL_VERBOSE);
+	cxt->flags |= (fl & MNT_FL_NOHELPERS);
+	cxt->flags |= (fl & MNT_FL_LOOPDEL);
+	cxt->flags |= (fl & MNT_FL_LAZY);
+	cxt->flags |= (fl & MNT_FL_FORK);
+	cxt->flags |= (fl & MNT_FL_FORCE);
+	cxt->flags |= (fl & MNT_FL_NOCANONICALIZE);
+	cxt->flags |= (fl & MNT_FL_RDONLY_UMOUNT);
+	cxt->flags |= (fl & MNT_FL_RWONLY_MOUNT);
+	cxt->flags |= (fl & MNT_FL_NOSWAPMATCH);
+	cxt->flags |= (fl & MNT_FL_TABPATHS_CHECKED);
+
+	mnt_context_apply_template(cxt);
+
+	return 0;
+}
+
+/*
+ * Saves the current context setting (mount options, etc) to make it usable after
+ * mnt_reset_context() or by mnt_context_apply_template(). This is usable for
+ * example for mnt_context_next_mount() where for the next mount operation we
+ * need to restore to the original context setting.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_save_template(struct libmnt_context *cxt)
+{
+	if (!cxt)
+		return -EINVAL;
+
+	DBG(CXT, ul_debugobj(cxt, "saving template"));
+
+	/* reset old saved data */
+	mnt_unref_optlist(cxt->optlist_saved);
+	cxt->optlist_saved = NULL;
+
+	if (cxt->optlist)
+		cxt->optlist_saved = mnt_copy_optlist(cxt->optlist);
+
+	return 0;
+}
+
+/*
+ * Restores context FS setting from previously saved template (see
+ * mnt_context_save_template()).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_apply_template(struct libmnt_context *cxt)
+{
+	if (!cxt)
+		return -EINVAL;
+
+	if (cxt->optlist) {
+		mnt_unref_optlist(cxt->optlist);
+		cxt->optlist = NULL;
+	}
+
+	if (cxt->optlist_saved) {
+		DBG(CXT, ul_debugobj(cxt, "restoring template"));
+		cxt->optlist = mnt_copy_optlist(cxt->optlist_saved);
+	}
+
+	return 0;
+}
+
+int mnt_context_has_template(struct libmnt_context *cxt)
+{
+	return cxt && cxt->optlist_saved ? 1 : 0;
+}
+
+struct libmnt_context *mnt_copy_context(struct libmnt_context *o)
+{
+	struct libmnt_context *n;
+
+	n = mnt_new_context();
+	if (!n)
+		return NULL;
+
+	DBG(CXT, ul_debugobj(n, "<---- clone ---->"));
+
+	n->flags = o->flags;
+
+	if (o->fs) {
+		n->fs = mnt_copy_fs(NULL, o->fs);
+		if (!n->fs)
+			goto failed;
+	}
+
+	n->mountinfo = o->mountinfo;
+	mnt_ref_table(n->mountinfo);
+
+	n->utab = o->utab;
+	mnt_ref_table(n->utab);
+
+	if (strdup_between_structs(n, o, tgt_prefix))
+		goto failed;
+	if (strdup_between_structs(n, o, helper))
+		goto failed;
+
+	n->map_linux = o->map_linux;
+	n->map_userspace = o->map_userspace;
+
+	mnt_context_reset_status(n);
+
+	n->table_fltrcb = o->table_fltrcb;
+	n->table_fltrcb_data = o->table_fltrcb_data;
+
+	n->noautofs = o->noautofs;
+	n->has_selinux_opt = o->has_selinux_opt;
+
+	return n;
+failed:
+	mnt_free_context(n);
+	return NULL;
+}
+
+/**
+ * mnt_context_reset_status:
+ * @cxt: context
+ *
+ * Resets mount(2) and mount.type statuses, so mnt_context_do_mount() or
+ * mnt_context_do_umount() could be again called with the same settings.
+ *
+ * BE CAREFUL -- after this soft reset the libmount will NOT parse mount
+ * options, evaluate permissions or apply stuff from fstab.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_reset_status(struct libmnt_context *cxt)
+{
+	if (!cxt)
+		return -EINVAL;
+
+	cxt->syscall_status = 1;		/* means not called yet */
+	cxt->helper_exec_status = 1;
+	cxt->helper_status = 0;
+	return 0;
+}
+
+static int context_init_paths(struct libmnt_context *cxt, int writable)
+{
+	struct libmnt_ns *ns_old;
+
+	assert(cxt);
+
+	if (!cxt->utab_path) {
+		cxt->utab_path = mnt_get_utab_path();
+		DBG(CXT, ul_debugobj(cxt, "utab path initialized to: %s", cxt->utab_path));
+	}
+
+	if (!writable)
+		return 0;		/* only paths wanted */
+	if (mnt_context_is_nomtab(cxt))
+		return 0;		/* write mode overridden by mount -n */
+	if (cxt->flags & MNT_FL_TABPATHS_CHECKED)
+		return 0;
+
+	DBG(CXT, ul_debugobj(cxt, "checking for writable tab files"));
+
+	ns_old = mnt_context_switch_target_ns(cxt);
+	if (!ns_old)
+		return -MNT_ERR_NAMESPACE;
+
+	mnt_has_regular_utab(&cxt->utab_path, &cxt->utab_writable);
+
+	if (!mnt_context_switch_ns(cxt, ns_old))
+		return -MNT_ERR_NAMESPACE;
+
+	cxt->flags |= MNT_FL_TABPATHS_CHECKED;
+	return 0;
+}
+
+int mnt_context_utab_writable(struct libmnt_context *cxt)
+{
+	assert(cxt);
+
+	context_init_paths(cxt, 1);
+	return cxt->utab_writable == 1;
+}
+
+const char *mnt_context_get_writable_tabpath(struct libmnt_context *cxt)
+{
+	assert(cxt);
+
+	context_init_paths(cxt, 1);
+	return cxt->utab_path;
+}
+
+
+static int set_flag(struct libmnt_context *cxt, int flag, int enable)
+{
+	if (!cxt)
+		return -EINVAL;
+	if (enable) {
+		DBG(CXT, ul_debugobj(cxt, "enabling flag %04x", flag));
+		cxt->flags |= flag;
+	} else {
+		DBG(CXT, ul_debugobj(cxt, "disabling flag %04x", flag));
+		cxt->flags &= ~flag;
+	}
+	return 0;
+}
+
+/**
+ * mnt_context_is_restricted:
+ * @cxt: mount context
+ *
+ * Returns: 0 for an unrestricted mount (user is root), or 1 for non-root mounts
+ */
+int mnt_context_is_restricted(struct libmnt_context *cxt)
+{
+	return cxt->restricted;
+}
+
+/**
+ * mnt_context_force_unrestricted:
+ * @cxt: mount context
+ *
+ * This function is DANGEROURS as it disables all security policies in libmount.
+ * Don't use if not sure. It removes "restricted" flag from the context, so
+ * libmount will use the current context as for root user.
+ *
+ * This function is designed for case you have no any suid permissions, so you
+ * can depend on kernel.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ *
+ * Since: 2.35
+ */
+int mnt_context_force_unrestricted(struct libmnt_context *cxt)
+{
+	if (mnt_context_is_restricted(cxt)) {
+		DBG(CXT, ul_debugobj(cxt, "force UNRESTRICTED"));
+		cxt->restricted = 0;
+	}
+
+	return 0;
+}
+
+/**
+ * mnt_context_set_optsmode
+ * @cxt: mount context
+ * @mode: MNT_OMODE_* flags
+ *
+ * Controls how to use mount optionssource and target paths from fstab/mountinfo.
+ *
+ * @MNT_OMODE_IGNORE: ignore fstab options
+ *
+ * @MNT_OMODE_APPEND: append fstab options to existing options
+ *
+ * @MNT_OMODE_PREPEND: prepend fstab options to existing options
+ *
+ * @MNT_OMODE_REPLACE: replace existing options with options from fstab
+ *
+ * @MNT_OMODE_FORCE: always read fstab (although source and target are defined)
+ *
+ * @MNT_OMODE_FSTAB: read from fstab
+ *
+ * @MNT_OMODE_MTAB: read from mountinfo if fstab not enabled or failed
+ *
+ * @MNT_OMODE_NOTAB: do not read fstab/mountinfoat all
+ *
+ * @MNT_OMODE_AUTO: default mode (MNT_OMODE_PREPEND | MNT_OMODE_FSTAB | MNT_OMODE_MTAB)
+ *
+ * @MNT_OMODE_USER: default for non-root users (MNT_OMODE_REPLACE | MNT_OMODE_FORCE | MNT_OMODE_FSTAB)
+ *
+ * Notes:
+ *
+ * - MNT_OMODE_USER is always used if mount context is in restricted mode
+ * - MNT_OMODE_AUTO is used if nothing else is defined
+ * - the flags are evaluated in this order: MNT_OMODE_NOTAB, MNT_OMODE_FORCE,
+ *   MNT_OMODE_FSTAB, MNT_OMODE_MTAB and then the mount options from fstab/mountinfo
+ *   are set according to MNT_OMODE_{IGNORE,APPEND,PREPEND,REPLACE}
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_optsmode(struct libmnt_context *cxt, int mode)
+{
+	if (!cxt)
+		return -EINVAL;
+	cxt->optsmode = mode;
+	return 0;
+}
+
+/**
+ * mnt_context_get_optsmode
+ * @cxt: mount context
+ *
+ * Returns: MNT_OMODE_* mask or zero.
+ */
+
+int mnt_context_get_optsmode(struct libmnt_context *cxt)
+{
+	return cxt->optsmode;
+}
+
+/**
+ * mnt_context_disable_canonicalize:
+ * @cxt: mount context
+ * @disable: TRUE or FALSE
+ *
+ * Enable/disable paths canonicalization and tags evaluation. The libmount context
+ * canonicalizes paths when searching in fstab and when preparing source and target paths
+ * for mount(2) syscall.
+ *
+ * This function has an effect on the private (within context) fstab instance only
+ * (see mnt_context_set_fstab()). If you want to use an external fstab then you
+ * need to manage your private struct libmnt_cache (see mnt_table_set_cache(fstab,
+ * NULL).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_disable_canonicalize(struct libmnt_context *cxt, int disable)
+{
+	return set_flag(cxt, MNT_FL_NOCANONICALIZE, disable);
+}
+
+/**
+ * mnt_context_is_nocanonicalize:
+ * @cxt: mount context
+ *
+ * Returns: 1 if no-canonicalize mode is enabled or 0.
+ */
+int mnt_context_is_nocanonicalize(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_NOCANONICALIZE ? 1 : 0;
+}
+
+/**
+ * mnt_context_enable_lazy:
+ * @cxt: mount context
+ * @enable: TRUE or FALSE
+ *
+ * Enable/disable lazy umount (see umount(8) man page, option -l).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_enable_lazy(struct libmnt_context *cxt, int enable)
+{
+	return set_flag(cxt, MNT_FL_LAZY, enable);
+}
+
+/**
+ * mnt_context_is_lazy:
+ * @cxt: mount context
+ *
+ * Returns: 1 if lazy umount is enabled or 0
+ */
+int mnt_context_is_lazy(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_LAZY ? 1 : 0;
+}
+
+/**
+ * mnt_context_enable_onlyonce:
+ * @cxt: mount context
+ * @enable: TRUE or FALSE
+ *
+ * Enable/disable only-once mount (check if FS is not already mounted).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_enable_onlyonce(struct libmnt_context *cxt, int enable)
+{
+	return set_flag(cxt, MNT_FL_ONLYONCE, enable);
+}
+
+/**
+ * mnt_context_is_lazy:
+ * @cxt: mount context
+ *
+ * Returns: 1 if lazy umount is enabled or 0
+ */
+int mnt_context_is_onlyonce(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_ONLYONCE ? 1 : 0;
+}
+
+/**
+ * mnt_context_enable_fork:
+ * @cxt: mount context
+ * @enable: TRUE or FALSE
+ *
+ * Enable/disable fork(2) call in mnt_context_next_mount() (see mount(8) man
+ * page, option -F).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_enable_fork(struct libmnt_context *cxt, int enable)
+{
+	return set_flag(cxt, MNT_FL_FORK, enable);
+}
+
+/**
+ * mnt_context_is_fork:
+ * @cxt: mount context
+ *
+ * Returns: 1 if fork (mount -F) is enabled or 0
+ */
+int mnt_context_is_fork(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_FORK ? 1 : 0;
+}
+
+/**
+ * mnt_context_is_parent:
+ * @cxt: mount context
+ *
+ * Return: 1 if mount -F enabled and the current context is parent, or 0
+ */
+int mnt_context_is_parent(struct libmnt_context *cxt)
+{
+	return mnt_context_is_fork(cxt) && cxt->pid == 0;
+}
+
+/**
+ * mnt_context_is_child:
+ * @cxt: mount context
+ *
+ * Return: 1 f the current context is child, or 0
+ */
+int mnt_context_is_child(struct libmnt_context *cxt)
+{
+	/* See mnt_fork_context(), the for fork flag is always disabled
+	 * for children to avoid recursive forking.
+	 */
+	return !mnt_context_is_fork(cxt) && cxt->pid;
+}
+
+/**
+ * mnt_context_enable_rdonly_umount:
+ * @cxt: mount context
+ * @enable: TRUE or FALSE
+ *
+ * Enable/disable read-only remount on failed umount(2)
+ * (see umount(8) man page, option -r).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_enable_rdonly_umount(struct libmnt_context *cxt, int enable)
+{
+	return set_flag(cxt, MNT_FL_RDONLY_UMOUNT, enable);
+}
+
+/**
+ * mnt_context_is_rdonly_umount
+ * @cxt: mount context
+ *
+ * See also mnt_context_enable_rdonly_umount() and umount(8) man page,
+ * option -r.
+ *
+ * Returns: 1 if read-only remount failed umount(2) is enables or 0
+ */
+int mnt_context_is_rdonly_umount(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_RDONLY_UMOUNT ? 1 : 0;
+}
+
+/**
+ * mnt_context_enable_rwonly_mount:
+ * @cxt: mount context
+ * @enable: TRUE or FALSE
+ *
+ * Force read-write mount; if enabled libmount will never try MS_RDONLY
+ * after failed mount(2) EROFS. (See mount(8) man page, option -w).
+ *
+ * Since: 2.30
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_enable_rwonly_mount(struct libmnt_context *cxt, int enable)
+{
+	return set_flag(cxt, MNT_FL_RWONLY_MOUNT, enable);
+}
+
+/**
+ * mnt_context_is_rwonly_mount
+ * @cxt: mount context
+ *
+ * See also mnt_context_enable_rwonly_mount() and mount(8) man page,
+ * option -w.
+ *
+ * Since: 2.30
+ *
+ * Returns: 1 if only read-write mount is allowed.
+ */
+int mnt_context_is_rwonly_mount(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_RWONLY_MOUNT ? 1 : 0;
+}
+
+/**
+ * mnt_context_forced_rdonly:
+ * @cxt: mount context
+ *
+ * See also mnt_context_enable_rwonly_mount().
+ *
+ * Since: 2.30
+ *
+ * Returns: 1 if mounted read-only on write-protected device.
+ */
+int mnt_context_forced_rdonly(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_FORCED_RDONLY ? 1 : 0;
+}
+
+/**
+ * mnt_context_disable_helpers:
+ * @cxt: mount context
+ * @disable: TRUE or FALSE
+ *
+ * Enable/disable /sbin/[u]mount.* helpers (see mount(8) man page, option -i).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_disable_helpers(struct libmnt_context *cxt, int disable)
+{
+	return set_flag(cxt, MNT_FL_NOHELPERS, disable);
+}
+
+/**
+ * mnt_context_is_nohelpers
+ * @cxt: mount context
+ *
+ * Returns: 1 if helpers are disabled (mount -i) or 0
+ */
+int mnt_context_is_nohelpers(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_NOHELPERS ? 1 : 0;
+}
+
+
+/**
+ * mnt_context_enable_sloppy:
+ * @cxt: mount context
+ * @enable: TRUE or FALSE
+ *
+ * Set/unset sloppy mounting (see mount(8) man page, option -s).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_enable_sloppy(struct libmnt_context *cxt, int enable)
+{
+	return set_flag(cxt, MNT_FL_SLOPPY, enable);
+}
+
+/**
+ * mnt_context_is_sloppy:
+ * @cxt: mount context
+ *
+ * Returns: 1 if sloppy flag is enabled or 0
+ */
+int mnt_context_is_sloppy(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_SLOPPY ? 1 : 0;
+}
+
+/**
+ * mnt_context_enable_fake:
+ * @cxt: mount context
+ * @enable: TRUE or FALSE
+ *
+ * Enable/disable fake mounting (see mount(8) man page, option -f).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_enable_fake(struct libmnt_context *cxt, int enable)
+{
+	return set_flag(cxt, MNT_FL_FAKE, enable);
+}
+
+/**
+ * mnt_context_is_fake:
+ * @cxt: mount context
+ *
+ * Returns: 1 if fake flag is enabled or 0
+ */
+int mnt_context_is_fake(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_FAKE ? 1 : 0;
+}
+
+/**
+ * mnt_context_disable_mtab:
+ * @cxt: mount context
+ * @disable: TRUE or FALSE
+ *
+ * Disable/enable userspace mount table update (see mount(8) man page,
+ * option -n). Originally /etc/mtab, now /run/mount/utab.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_disable_mtab(struct libmnt_context *cxt, int disable)
+{
+	return set_flag(cxt, MNT_FL_NOMTAB, disable);
+}
+
+/**
+ * mnt_context_is_nomtab:
+ * @cxt: mount context
+ *
+ * Returns: 1 if no-mtab is enabled or 0
+ */
+int mnt_context_is_nomtab(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_NOMTAB ? 1 : 0;
+}
+
+/**
+ * mnt_context_disable_swapmatch:
+ * @cxt: mount context
+ * @disable: TRUE or FALSE
+ *
+ * Disable/enable swap between source and target for mount(8) if only one path
+ * is specified.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_disable_swapmatch(struct libmnt_context *cxt, int disable)
+{
+	return set_flag(cxt, MNT_FL_NOSWAPMATCH, disable);
+}
+
+/**
+ * mnt_context_is_swapmatch:
+ * @cxt: mount context
+ *
+ * Returns: 1 if swap between source and target is allowed (default is 1) or 0.
+ */
+int mnt_context_is_swapmatch(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_NOSWAPMATCH ? 0 : 1;
+}
+
+/**
+ * mnt_context_enable_force:
+ * @cxt: mount context
+ * @enable: TRUE or FALSE
+ *
+ * Enable/disable force umounting (see umount(8) man page, option -f).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_enable_force(struct libmnt_context *cxt, int enable)
+{
+	return set_flag(cxt, MNT_FL_FORCE, enable);
+}
+
+/**
+ * mnt_context_is_force
+ * @cxt: mount context
+ *
+ * Returns: 1 if force umounting flag is enabled or 0
+ */
+int mnt_context_is_force(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_FORCE ? 1 : 0;
+}
+
+/**
+ * mnt_context_enable_verbose:
+ * @cxt: mount context
+ * @enable: TRUE or FALSE
+ *
+ * Enable/disable verbose output (TODO: not implemented yet)
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_enable_verbose(struct libmnt_context *cxt, int enable)
+{
+	return set_flag(cxt, MNT_FL_VERBOSE, enable);
+}
+
+/**
+ * mnt_context_is_verbose
+ * @cxt: mount context
+ *
+ * Returns: 1 if verbose flag is enabled or 0
+ */
+int mnt_context_is_verbose(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_VERBOSE ? 1 : 0;
+}
+
+/**
+ * mnt_context_enable_loopdel:
+ * @cxt: mount context
+ * @enable: TRUE or FALSE
+ *
+ * Enable/disable the loop delete (destroy) after umount (see umount(8), option -d)
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_enable_loopdel(struct libmnt_context *cxt, int enable)
+{
+	return set_flag(cxt, MNT_FL_LOOPDEL, enable);
+}
+
+/**
+ * mnt_context_is_loopdel:
+ * @cxt: mount context
+ *
+ * Returns: 1 if loop device should be deleted after umount (umount -d) or 0.
+ */
+int mnt_context_is_loopdel(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_LOOPDEL ? 1 : 0;
+}
+
+/**
+ * mnt_context_set_fs:
+ * @cxt: mount context
+ * @fs: filesystem description
+ *
+ * The mount context uses private @fs by default. This function can be used to
+ * overwrite the private @fs with an external instance. This function
+ * increments @fs reference counter (and decrement reference counter of the
+ * old fs).
+ *
+ * The @fs will be modified by mnt_context_set_{source,target,options,fstype}
+ * functions, If the @fs is NULL, then all current FS specific settings (source,
+ * target, etc., exclude spec) are reset.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_fs(struct libmnt_context *cxt, struct libmnt_fs *fs)
+{
+	if (!cxt)
+		return -EINVAL;
+
+	if (cxt->fs == fs)
+		return 0;
+
+	DBG(CXT, ul_debugobj(cxt, "setting new FS"));
+
+	/* new */
+	if (fs) {
+		struct libmnt_optlist *ol = mnt_context_get_optlist(cxt);
+
+		if (!ol)
+			return -ENOMEM;
+
+		mnt_ref_fs(fs);
+
+		mnt_optlist_set_optstr(ol, mnt_fs_get_options(fs), NULL);
+		mnt_fs_follow_optlist(fs, ol);
+	}
+
+	/* old */
+	if (cxt->fs)
+		mnt_fs_follow_optlist(cxt->fs, NULL);
+	mnt_unref_fs(cxt->fs);
+
+	cxt->fs = fs;
+	return 0;
+}
+
+/**
+ * mnt_context_get_fs:
+ * @cxt: mount context
+ *
+ * The FS contains the basic description of mountpoint, fs type and so on.
+ * Note that the FS is modified by mnt_context_set_{source,target,options,fstype}
+ * functions.
+ *
+ * Returns: pointer to FS description or NULL in case of a calloc() error.
+ */
+struct libmnt_fs *mnt_context_get_fs(struct libmnt_context *cxt)
+{
+	if (!cxt)
+		return NULL;
+	if (!cxt->fs) {
+		struct libmnt_optlist *ol = mnt_context_get_optlist(cxt);
+
+		if (!ol)
+			return NULL;
+		cxt->fs = mnt_new_fs();
+		if (!cxt->fs)
+			return NULL;
+
+		mnt_fs_follow_optlist(cxt->fs, ol);
+	}
+	return cxt->fs;
+}
+
+/**
+ * mnt_context_get_fs_userdata:
+ * @cxt: mount context
+ *
+ * Returns: pointer to userdata or NULL.
+ */
+void *mnt_context_get_fs_userdata(struct libmnt_context *cxt)
+{
+	return cxt->fs ? mnt_fs_get_userdata(cxt->fs) : NULL;
+}
+
+/**
+ * mnt_context_get_fstab_userdata:
+ * @cxt: mount context
+ *
+ * Returns: pointer to userdata or NULL.
+ */
+void *mnt_context_get_fstab_userdata(struct libmnt_context *cxt)
+{
+	return cxt->fstab ? mnt_table_get_userdata(cxt->fstab) : NULL;
+}
+
+/**
+ * mnt_context_get_mtab_userdata:
+ * @cxt: mount context
+ *
+ * The file /etc/mtab is no more used, @context points always to mountinfo
+ * (/proc/self/mountinfo). The function uses "mtab" in the name for backward
+ * compatibility only.
+ *
+ * Returns: pointer to userdata or NULL.
+ */
+void *mnt_context_get_mtab_userdata(struct libmnt_context *cxt)
+{
+	return cxt->mountinfo ? mnt_table_get_userdata(cxt->mountinfo) : NULL;
+}
+
+/**
+ * mnt_context_set_source:
+ * @cxt: mount context
+ * @source: mount source (device, directory, UUID, LABEL, ...)
+ *
+ * Note that libmount does not interpret "nofail" (MNT_MS_NOFAIL)
+ * mount option. The real return code is always returned, when
+ * the device does not exist then it's usually MNT_ERR_NOSOURCE
+ * from libmount or ENOENT, ENOTDIR, ENOTBLK, ENXIO from mount(2).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_source(struct libmnt_context *cxt, const char *source)
+{
+	return mnt_fs_set_source(mnt_context_get_fs(cxt), source);
+}
+
+/**
+ * mnt_context_get_source:
+ * @cxt: mount context
+ *
+ * Returns: returns pointer or NULL in case of error or if not set.
+ */
+const char *mnt_context_get_source(struct libmnt_context *cxt)
+{
+	return mnt_fs_get_source(mnt_context_get_fs(cxt));
+}
+
+/**
+ * mnt_context_set_target:
+ * @cxt: mount context
+ * @target: mountpoint
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_target(struct libmnt_context *cxt, const char *target)
+{
+	return mnt_fs_set_target(mnt_context_get_fs(cxt), target);
+}
+
+/**
+ * mnt_context_get_target:
+ * @cxt: mount context
+ *
+ * Returns: returns pointer or NULL in case of error or if not set.
+ */
+const char *mnt_context_get_target(struct libmnt_context *cxt)
+{
+	return mnt_fs_get_target(mnt_context_get_fs(cxt));
+}
+
+/**
+ * mnt_context_set_target_prefix:
+ * @cxt: mount context
+ * @path: mountpoint prefix
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_target_prefix(struct libmnt_context *cxt, const char *path)
+{
+	char *p = NULL;
+
+	if (!cxt)
+		return -EINVAL;
+	if (path) {
+		p = strdup(path);
+		if (!p)
+			return -ENOMEM;
+	}
+	free(cxt->tgt_prefix);
+	cxt->tgt_prefix = p;
+
+	return 0;
+}
+
+/**
+ * mnt_context_get_target_prefix:
+ * @cxt: mount context
+ *
+ * Returns: returns pointer or NULL in case of error or if not set.
+ */
+const char *mnt_context_get_target_prefix(struct libmnt_context *cxt)
+{
+	return cxt ? cxt->tgt_prefix : NULL;
+}
+
+
+/**
+ * mnt_context_set_fstype:
+ * @cxt: mount context
+ * @fstype: filesystem type
+ *
+ * Note that the @fstype has to be a FS type. For patterns with
+ * comma-separated list of filesystems or for the "nofs" notation, use
+ * mnt_context_set_fstype_pattern().
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_fstype(struct libmnt_context *cxt, const char *fstype)
+{
+	return mnt_fs_set_fstype(mnt_context_get_fs(cxt), fstype);
+}
+
+/**
+ * mnt_context_get_fstype:
+ * @cxt: mount context
+ *
+ * Returns: pointer or NULL in case of error or if not set.
+ */
+const char *mnt_context_get_fstype(struct libmnt_context *cxt)
+{
+	return mnt_fs_get_fstype(mnt_context_get_fs(cxt));
+}
+
+struct libmnt_optlist *mnt_context_get_optlist(struct libmnt_context *cxt)
+{
+	if (!cxt)
+		return NULL;
+	if (!cxt->optlist) {
+		cxt->optlist = mnt_new_optlist();
+		if (!cxt->optlist)
+			return NULL;
+		if (mnt_optlist_register_map(cxt->optlist, cxt->map_linux))
+			goto fail;
+		if (mnt_optlist_register_map(cxt->optlist, cxt->map_userspace))
+			goto fail;
+	}
+
+	return cxt->optlist;
+fail:
+	mnt_unref_optlist(cxt->optlist);
+	return NULL;
+}
+
+/**
+ * mnt_context_set_options:
+ * @cxt: mount context
+ * @optstr: comma delimited mount options
+ *
+ * Note that MS_MOVE cannot be specified as "string". It's operation that
+ * is no supported in fstab (etc.)
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_options(struct libmnt_context *cxt, const char *optstr)
+{
+	struct libmnt_optlist *ls = mnt_context_get_optlist(cxt);
+
+	if (!ls)
+		return -ENOMEM;
+	return mnt_optlist_set_optstr(ls, optstr, NULL);
+}
+
+/**
+ * mnt_context_append_options:
+ * @cxt: mount context
+ * @optstr: comma delimited mount options
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_append_options(struct libmnt_context *cxt, const char *optstr)
+{
+	struct libmnt_optlist *ls = mnt_context_get_optlist(cxt);
+
+	if (!ls)
+		return -ENOMEM;
+	return mnt_optlist_append_optstr(ls, optstr, NULL);
+}
+
+/**
+ * mnt_context_get_options:
+ * @cxt: mount context
+ *
+ * This function returns mount options set by mnt_context_set_options(),
+ * mnt_context_append_options() or mnt_context_set_mflags();
+ *
+ * Before v2.39 this function ignored options specified by flags (see
+ * mnt_context_set_mflags()) before mnt_context_prepare_mount() call. Now this
+ * function always returns all mount options.
+ *
+ * Returns: pointer or NULL
+ */
+const char *mnt_context_get_options(struct libmnt_context *cxt)
+{
+	const char *str = NULL;
+
+	if (cxt->optlist && !mnt_optlist_is_empty(cxt->optlist))
+		mnt_optlist_get_optstr(cxt->optlist, &str, NULL, 0);
+	return str;
+}
+
+/**
+ * mnt_context_set_fstype_pattern:
+ * @cxt: mount context
+ * @pattern: FS name pattern (or NULL to reset the current setting)
+ *
+ * See mount(8), option -t.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_fstype_pattern(struct libmnt_context *cxt, const char *pattern)
+{
+	char *p = NULL;
+
+	if (!cxt)
+		return -EINVAL;
+	if (pattern) {
+		p = strdup(pattern);
+		if (!p)
+			return -ENOMEM;
+	}
+	free(cxt->fstype_pattern);
+	cxt->fstype_pattern = p;
+	return 0;
+}
+
+/**
+ * mnt_context_set_options_pattern:
+ * @cxt: mount context
+ * @pattern: options pattern (or NULL to reset the current setting)
+ *
+ * See mount(8), option -O.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_options_pattern(struct libmnt_context *cxt, const char *pattern)
+{
+	char *p = NULL;
+
+	if (!cxt)
+		return -EINVAL;
+	if (pattern) {
+		p = strdup(pattern);
+		if (!p)
+			return -ENOMEM;
+	}
+	free(cxt->optstr_pattern);
+	cxt->optstr_pattern = p;
+	return 0;
+}
+
+/**
+ * mnt_context_set_fstab:
+ * @cxt: mount context
+ * @tb: fstab
+ *
+ * The mount context reads /etc/fstab to the private struct libmnt_table by default.
+ * This function can be used to overwrite the private fstab with an external
+ * instance.
+ *
+ * This function modify the @tb reference counter. This function does not set
+ * the cache for the @tb. You have to explicitly call mnt_table_set_cache(tb,
+ * mnt_context_get_cache(cxt));
+ *
+ * The fstab is used read-only and is not modified, it should be possible to
+ * share the fstab between more mount contexts (TODO: test it.)
+ *
+ * If the @tb argument is NULL, then the current private fstab instance is
+ * reset.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_fstab(struct libmnt_context *cxt, struct libmnt_table *tb)
+{
+	if (!cxt)
+		return -EINVAL;
+
+	mnt_ref_table(tb);		/* new */
+	mnt_unref_table(cxt->fstab);	/* old */
+
+	cxt->fstab = tb;
+	return 0;
+}
+
+/**
+ * mnt_context_get_fstab:
+ * @cxt: mount context
+ * @tb: returns fstab
+ *
+ * See also mnt_table_parse_fstab() for more details about fstab.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_get_fstab(struct libmnt_context *cxt, struct libmnt_table **tb)
+{
+	struct libmnt_ns *ns_old;
+
+	if (!cxt)
+		return -EINVAL;
+	if (!cxt->fstab) {
+		int rc;
+
+		cxt->fstab = mnt_new_table();
+		if (!cxt->fstab)
+			return -ENOMEM;
+		if (cxt->table_errcb)
+			mnt_table_set_parser_errcb(cxt->fstab, cxt->table_errcb);
+
+		ns_old = mnt_context_switch_target_ns(cxt);
+		if (!ns_old)
+			return -MNT_ERR_NAMESPACE;
+
+		mnt_table_set_cache(cxt->fstab, mnt_context_get_cache(cxt));
+		rc = mnt_table_parse_fstab(cxt->fstab, NULL);
+
+		if (!mnt_context_switch_ns(cxt, ns_old))
+			return -MNT_ERR_NAMESPACE;
+
+		if (rc)
+			return rc;
+	}
+
+	if (tb)
+		*tb = cxt->fstab;
+	return 0;
+}
+
+int mnt_context_get_mountinfo(struct libmnt_context *cxt, struct libmnt_table **tb)
+{
+	int rc = 0;
+	struct libmnt_ns *ns_old = NULL;
+
+	if (!cxt)
+		return -EINVAL;
+	if (!cxt->mountinfo) {
+		ns_old = mnt_context_switch_target_ns(cxt);
+		if (!ns_old)
+			return -MNT_ERR_NAMESPACE;
+
+		context_init_paths(cxt, 0);
+
+		cxt->mountinfo = mnt_new_table();
+		if (!cxt->mountinfo) {
+			rc = -ENOMEM;
+			goto end;
+		}
+
+		mnt_table_enable_noautofs(cxt->mountinfo, cxt->noautofs);
+
+		if (cxt->table_errcb)
+			mnt_table_set_parser_errcb(cxt->mountinfo, cxt->table_errcb);
+		if (cxt->table_fltrcb)
+			mnt_table_set_parser_fltrcb(cxt->mountinfo,
+					cxt->table_fltrcb,
+					cxt->table_fltrcb_data);
+
+		mnt_table_set_cache(cxt->mountinfo, mnt_context_get_cache(cxt));
+	}
+
+	/* Read the table; it's empty, because this first mnt_context_get_mountinfo()
+	 * call, or because /proc was not accessible in previous calls */
+	if (mnt_table_is_empty(cxt->mountinfo)) {
+		if (!ns_old) {
+			ns_old = mnt_context_switch_target_ns(cxt);
+			if (!ns_old)
+				return -MNT_ERR_NAMESPACE;
+		}
+
+		rc = __mnt_table_parse_mountinfo(cxt->mountinfo, NULL, cxt->utab);
+		if (rc)
+			goto end;
+	}
+
+	if (tb)
+		*tb = cxt->mountinfo;
+
+	DBG(CXT, ul_debugobj(cxt, "mountinfo requested [nents=%d]",
+				mnt_table_get_nents(cxt->mountinfo)));
+
+end:
+	if (ns_old && !mnt_context_switch_ns(cxt, ns_old))
+		return -MNT_ERR_NAMESPACE;
+
+	return rc;
+}
+
+/**
+ * mnt_context_get_mtab:
+ * @cxt: mount context
+ * @tb: returns mtab
+ *
+ * Parse /proc/self/mountinfo mount table.
+ *
+ * The file /etc/mtab is no more used, @context points always to mountinfo
+ * (/proc/self/mountinfo). The function uses "mtab" in the name for backward
+ * compatibility only.
+ *
+ * See also mnt_table_parse_mtab() for more details about mountinfo. The
+ * result will be deallocated by mnt_free_context(@cxt).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_get_mtab(struct libmnt_context *cxt, struct libmnt_table **tb)
+{
+	return mnt_context_get_mountinfo(cxt, tb);
+}
+
+/*
+ * Called by mountinfo parser to filter out entries, non-zero means that
+ * an entry has to be filtered out.
+ */
+static int mountinfo_filter(struct libmnt_fs *fs, void *data)
+{
+	if (!fs || !data)
+		return 0;
+	if (mnt_fs_streq_target(fs, data))
+		return 0;
+	if (mnt_fs_streq_srcpath(fs, data))
+		return 0;
+	return 1;
+}
+
+/*
+ * The same like mnt_context_get_mountinfo(), but does not read all mountinfo
+ * file, but only entries relevant for @tgt.
+ */
+int mnt_context_get_mountinfo_for_target(struct libmnt_context *cxt,
+				    struct libmnt_table **mountinfo,
+				    const char *tgt)
+{
+	struct stat st;
+	struct libmnt_cache *cache = NULL;
+	char *cn_tgt = NULL;
+	int rc;
+	struct libmnt_ns *ns_old;
+
+	ns_old = mnt_context_switch_target_ns(cxt);
+	if (!ns_old)
+		return -MNT_ERR_NAMESPACE;
+
+	if (mnt_context_is_nocanonicalize(cxt))
+		mnt_context_set_tabfilter(cxt, mountinfo_filter, (void *) tgt);
+
+	else if (mnt_safe_stat(tgt, &st) == 0 && S_ISDIR(st.st_mode)) {
+		cache = mnt_context_get_cache(cxt);
+		cn_tgt = mnt_resolve_path(tgt, cache);
+		if (cn_tgt)
+			mnt_context_set_tabfilter(cxt, mountinfo_filter, cn_tgt);
+	}
+
+	rc = mnt_context_get_mountinfo(cxt, mountinfo);
+	mnt_context_set_tabfilter(cxt, NULL, NULL);
+
+	if (!mnt_context_switch_ns(cxt, ns_old))
+		return -MNT_ERR_NAMESPACE;
+
+	if (cn_tgt && !cache)
+		free(cn_tgt);
+
+	return rc;
+}
+
+/*
+ * Allows to specify a filter for tab file entries. The filter is called by
+ * the table parser. Currently used for utab only.
+ */
+int mnt_context_set_tabfilter(struct libmnt_context *cxt,
+			      int (*fltr)(struct libmnt_fs *, void *),
+			      void *data)
+{
+	if (!cxt)
+		return -EINVAL;
+
+	cxt->table_fltrcb = fltr;
+	cxt->table_fltrcb_data = data;
+
+	if (cxt->mountinfo)
+		mnt_table_set_parser_fltrcb(cxt->mountinfo,
+				cxt->table_fltrcb,
+				cxt->table_fltrcb_data);
+
+	DBG(CXT, ul_debugobj(cxt, "tabfilter %s", fltr ? "ENABLED!" : "disabled"));
+	return 0;
+}
+
+/**
+ * mnt_context_get_table:
+ * @cxt: mount context
+ * @filename: e.g. /proc/self/mountinfo
+ * @tb: returns the table
+ *
+ * This function allocates a new table and parses the @file. The parser error
+ * callback and cache for tags and paths is set according to the @cxt setting.
+ * See also mnt_table_parse_file().
+ *
+ * It's strongly recommended to use the mnt_context_get_mtab() and
+ * mnt_context_get_fstab() functions for mountinfo and fstab files. This function
+ * does not care about LIBMOUNT_* env.variables and does not merge userspace
+ * options.
+ *
+ * The result will NOT be deallocated by mnt_free_context(@cxt).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_get_table(struct libmnt_context *cxt,
+			  const char *filename, struct libmnt_table **tb)
+{
+	int rc;
+	struct libmnt_ns *ns_old;
+
+	if (!cxt || !tb)
+		return -EINVAL;
+
+	*tb = mnt_new_table();
+	if (!*tb)
+		return -ENOMEM;
+
+	if (cxt->table_errcb)
+		mnt_table_set_parser_errcb(*tb, cxt->table_errcb);
+
+	ns_old = mnt_context_switch_target_ns(cxt);
+	if (!ns_old)
+		return -MNT_ERR_NAMESPACE;
+
+	rc = mnt_table_parse_file(*tb, filename);
+
+	if (rc) {
+		mnt_unref_table(*tb);
+		goto end;
+	}
+
+	mnt_table_set_cache(*tb, mnt_context_get_cache(cxt));
+
+end:
+	if (!mnt_context_switch_ns(cxt, ns_old))
+		return -MNT_ERR_NAMESPACE;
+
+	return rc;
+}
+
+/**
+ * mnt_context_set_tables_errcb
+ * @cxt: mount context
+ * @cb: pointer to callback function
+ *
+ * The error callback is used for all tab files (e.g. mountinfo, fstab)
+ * parsed within the context.
+ *
+ * See also mnt_context_get_mtab(),
+ *          mnt_context_get_fstab(),
+ *          mnt_table_set_parser_errcb().
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_tables_errcb(struct libmnt_context *cxt,
+	int (*cb)(struct libmnt_table *tb, const char *filename, int line))
+{
+	if (!cxt)
+		return -EINVAL;
+
+	if (cxt->mountinfo)
+		mnt_table_set_parser_errcb(cxt->mountinfo, cb);
+	if (cxt->fstab)
+		mnt_table_set_parser_errcb(cxt->fstab, cb);
+
+	cxt->table_errcb = cb;
+	return 0;
+}
+
+/**
+ * mnt_context_set_cache:
+ * @cxt: mount context
+ * @cache: cache instance or NULL
+ *
+ * The mount context maintains a private struct libmnt_cache by default. This
+ * function can be used to overwrite the private cache with an external instance.
+ * This function increments cache reference counter.
+ *
+ * If the @cache argument is NULL, then the current cache instance is reset.
+ * This function apply the cache to fstab and mountinfo instances (if already
+ * exists).
+ *
+ * The old cache instance reference counter is de-incremented.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_cache(struct libmnt_context *cxt, struct libmnt_cache *cache)
+{
+	if (!cxt)
+		return -EINVAL;
+
+	mnt_ref_cache(cache);			/* new */
+	mnt_unref_cache(cxt->cache);		/* old */
+
+	cxt->cache = cache;
+
+	if (cxt->mountinfo)
+		mnt_table_set_cache(cxt->mountinfo, cache);
+	if (cxt->fstab)
+		mnt_table_set_cache(cxt->fstab, cache);
+
+	return 0;
+}
+
+/**
+ * mnt_context_get_cache
+ * @cxt: mount context
+ *
+ * See also mnt_context_set_cache().
+ *
+ * Returns: pointer to cache or NULL if canonicalization is disabled.
+ */
+struct libmnt_cache *mnt_context_get_cache(struct libmnt_context *cxt)
+{
+	if (!cxt || mnt_context_is_nocanonicalize(cxt))
+		return NULL;
+
+	if (!cxt->cache) {
+		struct libmnt_cache *cache = mnt_new_cache();
+		mnt_context_set_cache(cxt, cache);
+		mnt_unref_cache(cache);
+	}
+	return cxt->cache;
+}
+
+/**
+ * mnt_context_set_passwd_cb:
+ * @cxt: mount context
+ * @get: callback to get password
+ * @release: callback to release (deallocate) password
+ *
+ * Sets callbacks for encryption password (e.g encrypted loopdev). This
+ * function is deprecated (encrypted loops are no longer supported).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_passwd_cb(struct libmnt_context *cxt,
+			      char *(*get)(struct libmnt_context *),
+			      void (*release)(struct libmnt_context *, char *))
+{
+	if (!cxt)
+		return -EINVAL;
+	cxt->pwd_get_cb = get;
+	cxt->pwd_release_cb = release;
+	return 0;
+}
+
+/**
+ * mnt_context_get_lock:
+ * @cxt: mount context
+ *
+ * The libmount applications don't have to care about utab locking, but with a
+ * small exception: the application has to be able to remove the lock file when
+ * interrupted by signal or signals have to be ignored when the lock is locked.
+ *
+ * The default behavior is to ignore all signals (except SIGALRM and
+ * SIGTRAP for utab update) when the lock is locked. If this behavior
+ * is unacceptable, then use:
+ *
+ *	lc = mnt_context_get_lock(cxt);
+ *	if (lc)
+ *		mnt_lock_block_signals(lc, FALSE);
+ *
+ * and don't forget to call mnt_unlock_file(lc) before exit.
+ *
+ * Returns: pointer to lock struct or NULL.
+ */
+struct libmnt_lock *mnt_context_get_lock(struct libmnt_context *cxt)
+{
+	/*
+	 * DON'T call this function within libmount, it will always allocate
+	 * the lock. The mnt_update_* functions are able to allocate the lock
+	 * only when utab update is really necessary.
+	 */
+	if (!cxt || mnt_context_is_nomtab(cxt))
+		return NULL;
+
+	if (!cxt->lock) {
+		cxt->lock = mnt_new_lock(
+				mnt_context_get_writable_tabpath(cxt), 0);
+		if (cxt->lock)
+			mnt_lock_block_signals(cxt->lock, TRUE);
+	}
+	return cxt->lock;
+}
+
+/**
+ * mnt_context_set_mflags:
+ * @cxt: mount context
+ * @flags: mount(2) flags (MS_* flags)
+ *
+ * Sets mount flags (see mount(2) man page).
+ *
+ * Note that order of mount options (strings) and flags matter if you mix
+ * mnt_context_append_options() and mnt_context_set_mflags().
+ *
+ * Be careful if use MS_REC flag -- this is flags is generic for
+ * all mask. In this case is better to use options string where
+ * mount options are independent and nothign is applied to all options.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_mflags(struct libmnt_context *cxt, unsigned long flags)
+{
+	struct libmnt_optlist *ls = mnt_context_get_optlist(cxt);
+
+	if (!ls)
+		return -ENOMEM;
+
+	return mnt_optlist_set_flags(ls, flags, cxt->map_linux);
+}
+
+/**
+ * mnt_context_get_mflags:
+ * @cxt: mount context
+ * @flags: returns MS_* mount flags
+ *
+ * Converts mount options string to MS_* flags and bitwise-OR the result with
+ * the already defined flags (see mnt_context_set_mflags()).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_get_mflags(struct libmnt_context *cxt, unsigned long *flags)
+{
+	struct libmnt_optlist *ls = mnt_context_get_optlist(cxt);
+
+	if (!ls)
+		return -ENOMEM;
+
+	return mnt_optlist_get_flags(ls, flags, cxt->map_linux, 0);
+}
+
+/**
+ * mnt_context_set_user_mflags:
+ * @cxt: mount context
+ * @flags: mount(2) flags (MNT_MS_* flags, e.g. MNT_MS_LOOP)
+ *
+ * Sets userspace mount flags.
+ *
+ * See also notes for mnt_context_set_mflags().
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_user_mflags(struct libmnt_context *cxt, unsigned long flags)
+{
+	struct libmnt_optlist *ls = mnt_context_get_optlist(cxt);
+
+	if (!ls)
+		return -ENOMEM;
+
+	return mnt_optlist_set_flags(ls, flags, cxt->map_userspace);
+}
+
+/**
+ * mnt_context_get_user_mflags:
+ * @cxt: mount context
+ * @flags: returns mount flags
+ *
+ * Converts mount options string to MNT_MS_* flags and bitwise-OR the result
+ * with the already defined flags (see mnt_context_set_user_mflags()).
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_get_user_mflags(struct libmnt_context *cxt, unsigned long *flags)
+{
+	struct libmnt_optlist *ls = mnt_context_get_optlist(cxt);
+
+	if (!ls)
+		return -ENOMEM;
+
+	return mnt_optlist_get_flags(ls, flags, cxt->map_userspace, 0);
+}
+
+/**
+ * mnt_context_set_mountdata:
+ * @cxt: mount context
+ * @data: mount(2) data
+ *
+ * The mount context generates mountdata from mount options by default. This
+ * function can be used to overwrite this behavior, and @data will be used instead
+ * of mount options.
+ *
+ * The libmount does not deallocate the data by mnt_free_context(). Note that
+ * NULL is also valid mount data.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_set_mountdata(struct libmnt_context *cxt, void *data)
+{
+	if (!cxt)
+		return -EINVAL;
+	cxt->mountdata = data;
+	cxt->flags |= MNT_FL_MOUNTDATA;
+	return 0;
+}
+
+/*
+ * Translates LABEL/UUID/path to mountable path
+ */
+int mnt_context_prepare_srcpath(struct libmnt_context *cxt)
+{
+	const char *path = NULL;
+	struct libmnt_cache *cache;
+	const char *t, *v, *src, *type;
+	int rc = 0;
+	struct libmnt_ns *ns_old;
+	struct libmnt_optlist *ol;
+
+	assert(cxt);
+	assert(cxt->fs);
+	assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));
+
+	DBG(CXT, ul_debugobj(cxt, "--> preparing source path"));
+
+	src = mnt_fs_get_source(cxt->fs);
+
+	if (!src && mnt_context_propagation_only(cxt))
+		/* mount --make-{shared,private,...} */
+		return mnt_fs_set_source(cxt->fs, "none");
+
+	/* ignore filesystems without source or filesystems
+	 * where the source is a quasi-path (//foo/bar)
+	 */
+	if (!src || mnt_fs_is_netfs(cxt->fs))
+		return 0;
+
+	/* ZFS source is always "dataset", not a real path */
+	type = mnt_fs_get_fstype(cxt->fs);
+	if (type && strcmp(type, "zfs") == 0)
+		return 0;
+
+	DBG(CXT, ul_debugobj(cxt, "srcpath '%s'", src));
+
+	ns_old = mnt_context_switch_target_ns(cxt);
+	if (!ns_old)
+		return -MNT_ERR_NAMESPACE;
+
+	cache = mnt_context_get_cache(cxt);
+
+	if (!mnt_fs_get_tag(cxt->fs, &t, &v)) {
+		/*
+		 * Source is TAG (evaluate)
+		 */
+		if (cache)
+			path = mnt_resolve_tag(t, v, cache);
+
+		rc = path ? mnt_fs_set_source(cxt->fs, path) : -MNT_ERR_NOSOURCE;
+
+	} else if (cache && !mnt_fs_is_pseudofs(cxt->fs)) {
+		/*
+		 * Source is PATH (canonicalize)
+		 */
+		path = mnt_resolve_path(src, cache);
+		if (path && strcmp(path, src) != 0)
+			rc = mnt_fs_set_source(cxt->fs, path);
+	 }
+
+	if (rc) {
+		DBG(CXT, ul_debugobj(cxt, "failed to prepare srcpath [rc=%d]", rc));
+		goto end;
+	}
+
+	if (!path)
+		path = src;
+
+	ol = mnt_context_get_optlist(cxt);
+	if (!ol)
+		return -ENOMEM;
+
+	if (mnt_optlist_is_bind(ol)
+	    || mnt_optlist_is_move(ol)
+	    || mnt_optlist_is_remount(ol)
+	    || mnt_fs_is_pseudofs(cxt->fs)) {
+		DBG(CXT, ul_debugobj(cxt, "REMOUNT/BIND/MOVE/pseudo FS source: %s", path));
+		goto end;
+	}
+
+	rc = mnt_context_call_hooks(cxt, MNT_STAGE_PREP_SOURCE);
+	if (rc)
+		goto end;
+
+	DBG(CXT, ul_debugobj(cxt, "final srcpath '%s'",
+				mnt_fs_get_source(cxt->fs)));
+
+end:
+	if (!mnt_context_switch_ns(cxt, ns_old))
+		return -MNT_ERR_NAMESPACE;
+	return rc;
+}
+
+/* Guess type, but not set to cxt->fs, always use free() for the result. It's
+ * no error when we're not able to guess a filesystem type. Note that error
+ * does not mean that result in @type is NULL.
+ */
+int mnt_context_guess_srcpath_fstype(struct libmnt_context *cxt, char **type)
+{
+	int rc = 0;
+	struct libmnt_ns *ns_old;
+	const char *dev;
+
+	assert(type);
+	assert(cxt);
+
+	*type = NULL;
+
+	dev = mnt_fs_get_srcpath(cxt->fs);
+	if (!dev)
+		return 0;
+
+	ns_old = mnt_context_switch_target_ns(cxt);
+	if (!ns_old)
+		return -MNT_ERR_NAMESPACE;
+
+	if (access(dev, F_OK) == 0) {
+		struct libmnt_cache *cache = mnt_context_get_cache(cxt);
+		int ambi = 0;
+
+		*type = mnt_get_fstype(dev, &ambi, cache);
+		if (ambi)
+			rc = -MNT_ERR_AMBIFS;
+
+		if (cache && *type) {
+			*type = strdup(*type);
+			if (!*type)
+				rc = -ENOMEM;
+		}
+	} else {
+		DBG(CXT, ul_debugobj(cxt, "access(%s) failed [%m]", dev));
+		if (strchr(dev, ':') != NULL) {
+			*type = strdup("nfs");
+			if (!*type)
+				rc = -ENOMEM;
+		} else if (!strncmp(dev, "//", 2)) {
+			*type = strdup("cifs");
+			if (!*type)
+				rc = -ENOMEM;
+		}
+	}
+
+	if (!mnt_context_switch_ns(cxt, ns_old))
+		return -MNT_ERR_NAMESPACE;
+
+	if (rc == 0 && *type) {
+		struct libmnt_optlist *ol = mnt_context_get_optlist(cxt);
+		struct libmnt_opt *opt;
+		const char *allowed;
+
+		if (!ol)
+			return -ENOMEM;
+
+		opt = mnt_optlist_get_named(ol,
+				"X-mount.auto-fstypes", cxt->map_userspace);
+
+		if (opt
+		    && (allowed = mnt_opt_get_value(opt))
+		    && !match_fstype(*type, allowed)) {
+			DBG(CXT, ul_debugobj(cxt, "%s is not allowed by auto-fstypes=%s",
+						*type, allowed));
+			free(*type);
+			*type = NULL;
+			rc = -MNT_ERR_NOFSTYPE;
+		}
+	}
+
+	return rc;
+}
+
+/*
+ * It's usually no error when we're not able to detect the filesystem type -- we
+ * will try to use the types from /{etc,proc}/filesystems.
+ */
+int mnt_context_guess_fstype(struct libmnt_context *cxt)
+{
+	struct libmnt_optlist *ol;
+	char *type;
+	int rc = 0;
+
+	assert(cxt);
+	assert(cxt->fs);
+	assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));
+
+	DBG(CXT, ul_debugobj(cxt, "--> preparing fstype"));
+
+	ol = mnt_context_get_optlist(cxt);
+	if (!ol)
+		return -ENOMEM;
+
+	if (mnt_optlist_is_bind(ol)
+	    || mnt_optlist_is_move(ol)
+	    || mnt_context_propagation_only(cxt))
+		goto none;
+
+	type = (char *) mnt_fs_get_fstype(cxt->fs);
+	if (type && !strcmp(type, "auto")) {
+		mnt_fs_set_fstype(cxt->fs, NULL);
+		type = NULL;
+	}
+
+	if (type)
+		goto done;
+	if (mnt_optlist_is_remount(ol))
+		goto none;
+	if (cxt->fstype_pattern)
+		goto done;
+
+	rc = mnt_context_guess_srcpath_fstype(cxt, &type);
+	if (rc == 0 && type)
+		__mnt_fs_set_fstype_ptr(cxt->fs, type);
+	else
+		free(type);
+done:
+	DBG(CXT, ul_debugobj(cxt, "FS type: %s [rc=%d]",
+				mnt_fs_get_fstype(cxt->fs), rc));
+	return rc;
+none:
+	return mnt_fs_set_fstype(cxt->fs, "none");
+}
+
+/*
+ * The default is to use fstype from cxt->fs, this could be overwritten by
+ * @type. The @act is MNT_ACT_{MOUNT,UMOUNT}.
+ *
+ * Returns: 0 on success or negative number in case of error. Note that success
+ * does not mean that there is any usable helper, you have to check cxt->helper.
+ */
+int mnt_context_prepare_helper(struct libmnt_context *cxt, const char *name,
+				const char *type)
+{
+	char search_path[] = FS_SEARCH_PATH;		/* from config.h */
+	char *p = NULL, *path;
+	struct libmnt_ns *ns_old;
+	int rc = 0;
+
+	assert(cxt);
+	assert(cxt->fs);
+	assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));
+
+	DBG(CXT, ul_debugobj(cxt, "checking for helper"));
+
+	if (cxt->helper) {
+		free(cxt->helper);
+		cxt->helper = NULL;
+	}
+
+	if (!type)
+		type = mnt_fs_get_fstype(cxt->fs);
+
+	if (type && strchr(type, ','))
+		return 0;			/* type is fstype pattern */
+
+	if (mnt_context_is_nohelpers(cxt)
+	    || !type
+	    || !strcmp(type, "none")
+	    || strstr(type, "/..")		/* don't try to smuggle path */
+	    || mnt_fs_is_swaparea(cxt->fs))
+		return 0;
+
+	ns_old = mnt_context_switch_origin_ns(cxt);
+	if (!ns_old)
+		return -MNT_ERR_NAMESPACE;
+
+	/* Ignore errors when search in $PATH and do not modify @rc
+	 */
+	path = strtok_r(search_path, ":", &p);
+	while (path) {
+		char helper[PATH_MAX];
+		int len, found = 0;
+
+		len = snprintf(helper, sizeof(helper), "%s/%s.%s",
+						path, name, type);
+		path = strtok_r(NULL, ":", &p);
+
+		if (len < 0 || (size_t) len >= sizeof(helper))
+			continue;
+
+		found = mnt_is_path(helper);
+		if (!found && strchr(type, '.')) {
+			/* If type ends with ".subtype" try without it */
+			char *hs = strrchr(helper, '.');
+			if (hs)
+				*hs = '\0';
+			found = mnt_is_path(helper);
+		}
+
+		DBG(CXT, ul_debugobj(cxt, "%-25s ... %s", helper,
+					found ? "found" : "not found"));
+		if (!found)
+			continue;
+
+		/* success */
+		rc = strdup_to_struct_member(cxt, helper, helper);
+		break;
+	}
+
+	if (!mnt_context_switch_ns(cxt, ns_old))
+		rc = -MNT_ERR_NAMESPACE;
+
+	/* make sure helper is not set on error */
+	if (rc) {
+		free(cxt->helper);
+		cxt->helper = NULL;
+	}
+	return rc;
+}
+
+/* stop differentiate between options defined by flags and strings */
+int mnt_context_merge_mflags(struct libmnt_context *cxt)
+{
+	struct libmnt_optlist *ls = mnt_context_get_optlist(cxt);
+
+	if (!ls)
+		return -ENOMEM;
+
+	/* TODO: optlist returns always flags as merged, so
+	 * MNT_FL_MOUNTFLAGS_MERGED is unncessary anymore
+	 */
+	cxt->flags |= MNT_FL_MOUNTFLAGS_MERGED;
+	return mnt_optlist_merge_opts(ls);
+}
+
+/*
+ * Prepare /run/mount/utab
+ */
+int mnt_context_prepare_update(struct libmnt_context *cxt)
+{
+	int rc;
+	const char *target, *name;
+	unsigned long flags = 0;
+
+	assert(cxt);
+	assert(cxt->fs);
+	assert(cxt->action);
+	assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));
+
+	DBG(CXT, ul_debugobj(cxt, "--> prepare update"));
+
+	if (mnt_context_propagation_only(cxt)) {
+		DBG(CXT, ul_debugobj(cxt, "skip update: only MS_PROPAGATION"));
+		return 0;
+	}
+
+	target = mnt_fs_get_target(cxt->fs);
+
+	if (cxt->action == MNT_ACT_UMOUNT && target && !strcmp(target, "/")) {
+		DBG(CXT, ul_debugobj(cxt, "root umount: setting NOMTAB"));
+		mnt_context_disable_mtab(cxt, TRUE);
+	}
+	if (mnt_context_is_nomtab(cxt)) {
+		DBG(CXT, ul_debugobj(cxt, "skip update: NOMTAB flag"));
+		return 0;
+	}
+	name = mnt_context_get_writable_tabpath(cxt);
+	if (!name) {
+		DBG(CXT, ul_debugobj(cxt, "skip update: no writable destination"));
+		return 0;
+	}
+	/* 0 = success, 1 = not called yet */
+	if (cxt->syscall_status != 1 && cxt->syscall_status != 0) {
+		DBG(CXT, ul_debugobj(cxt,
+				"skip update: syscall failed [status=%d]",
+				cxt->syscall_status));
+		return 0;
+	}
+
+	if (!cxt->update) {
+		if (cxt->action == MNT_ACT_UMOUNT && is_file_empty(name)) {
+			DBG(CXT, ul_debugobj(cxt, "skip update: umount, no table"));
+			return 0;
+		}
+
+		cxt->update = mnt_new_update();
+		if (!cxt->update)
+			return -ENOMEM;
+
+		mnt_update_set_filename(cxt->update, name);
+	}
+
+	mnt_context_get_mflags(cxt, &flags);
+
+	if (cxt->action == MNT_ACT_UMOUNT)
+		rc = mnt_update_set_fs(cxt->update, flags,
+					mnt_context_get_target(cxt), NULL);
+	else
+		rc = mnt_update_set_fs(cxt->update, flags,
+					NULL, cxt->fs);
+
+	return rc < 0 ? rc : 0;
+}
+
+int mnt_context_update_tabs(struct libmnt_context *cxt)
+{
+	int rc = 0;
+	struct libmnt_ns *ns_old;
+
+	assert(cxt);
+
+	if (mnt_context_is_nomtab(cxt)) {
+		DBG(CXT, ul_debugobj(cxt, "don't update: NOMTAB flag"));
+		return 0;
+	}
+	if (!cxt->update || !mnt_update_is_ready(cxt->update)) {
+		DBG(CXT, ul_debugobj(cxt, "don't update: no update prepared"));
+		return 0;
+	}
+
+	ns_old = mnt_context_switch_target_ns(cxt);
+	if (!ns_old)
+		return -MNT_ERR_NAMESPACE;
+
+	/* check utab update when external helper executed */
+	if (mnt_context_helper_executed(cxt)
+	    && mnt_context_get_helper_status(cxt) == 0
+	    && mnt_context_utab_writable(cxt)) {
+
+		if (mnt_update_already_done(cxt->update, cxt->lock)) {
+			DBG(CXT, ul_debugobj(cxt, "don't update: error evaluate or already updated"));
+			goto end;
+		}
+	} else if (cxt->helper) {
+		DBG(CXT, ul_debugobj(cxt, "don't update: external helper"));
+		goto end;
+	}
+
+	if (cxt->syscall_status != 0
+	    && !(mnt_context_helper_executed(cxt) &&
+		 mnt_context_get_helper_status(cxt) == 0)) {
+
+		DBG(CXT, ul_debugobj(cxt, "don't update: syscall/helper failed/not called"));
+		goto end;
+	}
+
+	rc = mnt_update_table(cxt->update, cxt->lock);
+
+end:
+	if (!mnt_context_switch_ns(cxt, ns_old))
+		return -MNT_ERR_NAMESPACE;
+	return rc;
+}
+
+/* apply @fs to @cxt;
+ *
+ * @mflags are mount flags as specified on command-line -- used only to save
+ * MS_RDONLY which is allowed for non-root users.
+ */
+static int apply_fs(struct libmnt_context *cxt, struct libmnt_fs *fs, unsigned long mflags)
+{
+	struct libmnt_optlist *ls;
+	int rc;
+
+
+
+	if (!cxt->optsmode) {
+		if (mnt_context_is_restricted(cxt)) {
+			DBG(CXT, ul_debugobj(cxt, "force fstab usage for non-root users!"));
+			cxt->optsmode = MNT_OMODE_USER;
+		} else {
+			DBG(CXT, ul_debugobj(cxt, "use default optsmode"));
+			cxt->optsmode = MNT_OMODE_AUTO;
+		}
+
+	}
+
+	if (!mnt_context_get_fs(cxt))
+		return -ENOMEM;
+
+	DBG(CXT, ul_debugobj(cxt, "apply entry:"));
+	DBG(CXT, mnt_fs_print_debug(fs, stderr));
+	DBG(CXT, ul_debugobj(cxt, "OPTSMODE (opt-part): ignore=%d, append=%d, prepend=%d, replace=%d",
+				  cxt->optsmode & MNT_OMODE_IGNORE ? 1 : 0,
+				  cxt->optsmode & MNT_OMODE_APPEND ? 1 : 0,
+				  cxt->optsmode & MNT_OMODE_PREPEND ? 1 : 0,
+				  cxt->optsmode & MNT_OMODE_REPLACE ? 1 : 0));
+
+	/* copy from fs to our FS description
+	 */
+	rc = mnt_fs_set_source(cxt->fs, mnt_fs_get_source(fs));
+	if (!rc)
+		rc = mnt_fs_set_target(cxt->fs, mnt_fs_get_target(fs));
+
+	if (!rc && !mnt_fs_get_fstype(cxt->fs))
+		rc = mnt_fs_set_fstype(cxt->fs, mnt_fs_get_fstype(fs));
+
+	if (!rc && !mnt_fs_get_root(cxt->fs) && mnt_fs_get_root(fs))
+		rc = mnt_fs_set_root(cxt->fs, mnt_fs_get_root(fs));
+
+	if (rc)
+		goto done;
+
+	ls = mnt_context_get_optlist(cxt);
+	if (!ls) {
+		rc = -ENOMEM;
+		goto done;
+	}
+
+	if (cxt->optsmode & MNT_OMODE_IGNORE)
+		;
+	else if (cxt->optsmode & MNT_OMODE_REPLACE) {
+		rc = mnt_optlist_set_optstr(ls, mnt_fs_get_options(fs), NULL);
+
+		/* mount --read-only for non-root users is allowed */
+		if (rc == 0 && (mflags & MS_RDONLY)
+		    && mnt_context_is_restricted(cxt)
+		    && cxt->optsmode == MNT_OMODE_USER)
+			rc = mnt_optlist_append_optstr(ls, "ro", NULL);
+	}
+	else if (cxt->optsmode & MNT_OMODE_APPEND)
+		rc = mnt_optlist_append_optstr(ls, mnt_fs_get_options(fs), NULL);
+
+	else if (cxt->optsmode & MNT_OMODE_PREPEND)
+		rc = mnt_optlist_prepend_optstr(ls, mnt_fs_get_options(fs), NULL);
+
+	if (!rc)
+		cxt->flags |= MNT_FL_TAB_APPLIED;
+
+done:
+	DBG(CXT, ul_debugobj(cxt, "final entry [rc=%d]", rc));
+	DBG(CXT, mnt_fs_print_debug(cxt->fs, stderr));
+
+	return rc;
+}
+
+static int apply_table(struct libmnt_context *cxt, struct libmnt_table *tb,
+		     int direction, unsigned long mflags)
+{
+	struct libmnt_fs *fs = NULL;
+	const char *src, *tgt;
+
+	assert(cxt);
+	assert(cxt->fs);
+
+	src = mnt_fs_get_source(cxt->fs);
+	tgt = mnt_fs_get_target(cxt->fs);
+
+	if (tgt && src)
+		fs = mnt_table_find_pair(tb, src, tgt, direction);
+	else {
+		if (src)
+			fs = mnt_table_find_source(tb, src, direction);
+		else if (tgt)
+			fs = mnt_table_find_target(tb, tgt, direction);
+
+		if (!fs && mnt_context_is_swapmatch(cxt)) {
+			/* swap source and target (if @src is not LABEL/UUID),
+			 * for example in
+			 *
+			 *	mount /foo/bar
+			 *
+			 * the path could be a mountpoint as well as a source (for
+			 * example bind mount, symlink to a device, ...).
+			 */
+			if (src && !mnt_fs_get_tag(cxt->fs, NULL, NULL))
+				fs = mnt_table_find_target(tb, src, direction);
+			if (!fs && tgt)
+				fs = mnt_table_find_source(tb, tgt, direction);
+		}
+	}
+
+	if (!fs)
+		return -MNT_ERR_NOFSTAB;	/* not found */
+
+	return apply_fs(cxt, fs, mflags);
+}
+
+/* apply @fs to @cxt -- use mnt_context_apply_fstab() if not sure
+ */
+int mnt_context_apply_fs(struct libmnt_context *cxt, struct libmnt_fs *fs)
+{
+	return apply_fs(cxt, fs, 0);
+}
+
+/**
+ * mnt_context_apply_fstab:
+ * @cxt: mount context
+ *
+ * This function is optional.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_apply_fstab(struct libmnt_context *cxt)
+{
+	int rc = -1, isremount = 0, iscmdbind = 0;
+	struct libmnt_ns *ns_old;
+	struct libmnt_table *tab = NULL;
+	const char *src = NULL, *tgt = NULL;
+	unsigned long mflags = 0;
+
+	if (!cxt || !cxt->fs)
+		return -EINVAL;
+
+	if (mnt_context_tab_applied(cxt)) {	/* already applied */
+		DBG(CXT, ul_debugobj(cxt, "fstab already applied -- skip"));
+		return 0;
+	}
+
+	if (mnt_context_is_restricted(cxt)) {
+		DBG(CXT, ul_debugobj(cxt, "force fstab usage for non-root users!"));
+		cxt->optsmode = MNT_OMODE_USER;
+	} else if (cxt->optsmode == 0) {
+		DBG(CXT, ul_debugobj(cxt, "use default optsmode"));
+		cxt->optsmode = MNT_OMODE_AUTO;
+	} else if (cxt->optsmode & MNT_OMODE_NOTAB) {
+		cxt->optsmode &= ~MNT_OMODE_FSTAB;
+		cxt->optsmode &= ~MNT_OMODE_MTAB;
+		cxt->optsmode &= ~MNT_OMODE_FORCE;
+	}
+
+	if (mnt_context_get_mflags(cxt, &mflags) == 0) {
+		isremount = !!(mflags & MS_REMOUNT);
+		iscmdbind = !!(mflags & MS_BIND);
+	}
+
+	if (cxt->fs) {
+		src = mnt_fs_get_source(cxt->fs);
+		tgt = mnt_fs_get_target(cxt->fs);
+	}
+
+	DBG(CXT, ul_debugobj(cxt, "OPTSMODE (file-part): force=%d, fstab=%d, mtab=%d",
+				  cxt->optsmode & MNT_OMODE_FORCE ? 1 : 0,
+				  cxt->optsmode & MNT_OMODE_FSTAB ? 1 : 0,
+				  cxt->optsmode & MNT_OMODE_MTAB ? 1 : 0));
+
+	/* fstab is not required if source and target are specified */
+	if (src && tgt && !(cxt->optsmode & MNT_OMODE_FORCE)) {
+		DBG(CXT, ul_debugobj(cxt, "fstab not required -- skip"));
+		return 0;
+	}
+
+	if (!src && tgt
+	    && !(cxt->optsmode & MNT_OMODE_FSTAB)
+	    && !(cxt->optsmode & MNT_OMODE_MTAB)) {
+		DBG(CXT, ul_debugobj(cxt, "only target; fstab/mtab not required "
+					  "-- skip, probably MS_PROPAGATION"));
+		return 0;
+	}
+
+	/* let's initialize cxt->fs */
+	ignore_result( mnt_context_get_fs(cxt) );
+
+	ns_old = mnt_context_switch_target_ns(cxt);
+	if (!ns_old)
+		return -MNT_ERR_NAMESPACE;
+
+	/* try fstab */
+	if (cxt->optsmode & MNT_OMODE_FSTAB) {
+		DBG(CXT, ul_debugobj(cxt, "trying to apply fstab (src=%s, target=%s)", src, tgt));
+		rc = mnt_context_get_fstab(cxt, &tab);
+		if (!rc)
+			rc = apply_table(cxt, tab, MNT_ITER_FORWARD, mflags);
+	}
+
+	/* try mountinfo */
+	if (rc < 0 && (cxt->optsmode & MNT_OMODE_MTAB)
+	    && (isremount || cxt->action == MNT_ACT_UMOUNT)) {
+		DBG(CXT, ul_debugobj(cxt, "trying to apply mountinfo (src=%s, target=%s)", src, tgt));
+		if (tgt)
+			rc = mnt_context_get_mountinfo_for_target(cxt, &tab, tgt);
+		else
+			rc = mnt_context_get_mountinfo(cxt, &tab);
+		if (!rc)
+			rc = apply_table(cxt, tab, MNT_ITER_BACKWARD, mflags);
+	}
+
+	if (!mnt_context_switch_ns(cxt, ns_old))
+		return -MNT_ERR_NAMESPACE;
+
+	if (rc) {
+		if (!mnt_context_is_restricted(cxt)
+		    && tgt && !src
+		    && isremount) {
+			DBG(CXT, ul_debugobj(cxt, "only target; ignore missing mountinfo entry on remount"));
+			return 0;
+		}
+
+		DBG(CXT, ul_debugobj(cxt, "failed to find entry in fstab/mountinfo [rc=%d]: %m", rc));
+
+		/* force to "not found in fstab/mountinfo" error, the details why
+		 * not found are not so important and may be misinterpreted by
+		 * applications... */
+		rc = -MNT_ERR_NOFSTAB;
+
+
+	} else if (isremount && !iscmdbind && cxt->optlist) {
+
+		/* ignore "bind" on remount when the flag is read from fstab */
+		mnt_optlist_remove_named(cxt->optlist, "bind", NULL);
+	}
+	return rc;
+}
+
+/**
+ * mnt_context_tab_applied:
+ * @cxt: mount context
+ *
+ * Returns: 1 if fstab (or mountinfo) has been applied to the context, or 0.
+ */
+int mnt_context_tab_applied(struct libmnt_context *cxt)
+{
+	return cxt->flags & MNT_FL_TAB_APPLIED;
+}
+
+/*
+ * This is not a public function!
+ *
+ * Returns 1 if *only propagation flags* change is requested.
+ */
+int mnt_context_propagation_only(struct libmnt_context *cxt)
+{
+	struct libmnt_optlist *ls;
+
+	if (cxt->action != MNT_ACT_MOUNT)
+		return 0;
+	if (cxt->mountdata || cxt->fs == NULL)
+		return 0;
+	if (cxt->fs->fstype && strcmp(cxt->fs->fstype, "none") != 0)
+		return 0;
+	if (cxt->fs->source && strcmp(cxt->fs->source, "none") != 0)
+		return 0;
+
+	ls = mnt_context_get_optlist(cxt);
+	return ls ? mnt_optlist_is_propagation_only(ls) : 0;
+}
+
+/**
+ * mnt_context_get_status:
+ * @cxt: mount context
+ *
+ * Global libmount status.
+ *
+ * The real exit code of the mount.type helper has to be tested by
+ * mnt_context_get_helper_status(). The mnt_context_get_status() only informs
+ * that exec() has been successful.
+ *
+ * Returns: 1 if mount.type or mount(2) syscall has been successfully called.
+ */
+int mnt_context_get_status(struct libmnt_context *cxt)
+{
+	return !cxt->syscall_status || !cxt->helper_exec_status;
+}
+
+/**
+ * mnt_context_helper_executed:
+ * @cxt: mount context
+ *
+ * Returns: 1 if mount.type helper has been executed, or 0.
+ */
+int mnt_context_helper_executed(struct libmnt_context *cxt)
+{
+	return cxt->helper_exec_status != 1;
+}
+
+/**
+ * mnt_context_get_helper_status:
+ * @cxt: mount context
+ *
+ * Return: mount.type helper exit status, result is reliable only if
+ *         mnt_context_helper_executed() returns 1.
+ */
+int mnt_context_get_helper_status(struct libmnt_context *cxt)
+{
+	return cxt->helper_status;
+}
+
+/**
+ * mnt_context_syscall_called:
+ * @cxt: mount context
+ *
+ * Returns: 1 if mount(2) syscall has been called, or 0.
+ */
+int mnt_context_syscall_called(struct libmnt_context *cxt)
+{
+	return cxt->syscall_status != 1;
+}
+
+/**
+ * mnt_context_get_syscall_errno:
+ * @cxt: mount context
+ *
+ * The result from this function is reliable only if
+ * mnt_context_syscall_called() returns 1.
+ *
+ * Returns: mount(2) errno if the syscall failed or 0.
+ */
+int mnt_context_get_syscall_errno(struct libmnt_context *cxt)
+{
+	if (cxt->syscall_status < 0)
+		return -cxt->syscall_status;
+	return 0;
+}
+
+/**
+ * mnt_context_set_syscall_status:
+ * @cxt: mount context
+ * @status: mount(2) status
+ *
+ * The @status should be 0 on success, or negative number on error (-errno).
+ *
+ * This function should only be used if the [u]mount(2) syscall is NOT called by
+ * libmount code.
+ *
+ * Returns: 0 or negative number in case of error.
+ */
+int mnt_context_set_syscall_status(struct libmnt_context *cxt, int status)
+{
+	if (!cxt)
+		return -EINVAL;
+
+	DBG(CXT, ul_debugobj(cxt, "syscall status set to: %d", status));
+	cxt->syscall_status = status;
+	return 0;
+}
+
+/**
+ * mnt_context_strerror
+ * @cxt: context
+ * @buf: buffer
+ * @bufsiz: size of the buffer
+ *
+ * Not implemented, deprecated in favor or mnt_context_get_excode().
+ *
+ * Returns: 0 or negative number in case of error.
+ */
+int mnt_context_strerror(struct libmnt_context *cxt __attribute__((__unused__)),
+			 char *buf __attribute__((__unused__)),
+			 size_t bufsiz __attribute__((__unused__)))
+{
+	/* TODO: based on cxt->syscall_errno or cxt->helper_status */
+	return 0;
+}
+
+/**
+ * mnt_context_enable_noautofs:
+ * @cxt: context
+ * @ignore: ignore or don't ignore
+ *
+ * Enable/disable ignore autofs mount table entries on reading the
+ * mount table. Only effective if the "ignore" mount option is being
+ * used for autofs mounts (such as if automount(8) has been configured
+ * to do so).
+ */
+int mnt_context_enable_noautofs(struct libmnt_context *cxt, int ignore)
+{
+	if (!cxt)
+		return -EINVAL;
+	cxt->noautofs = ignore ? 1 : 0;
+	return 0;
+}
+
+int mnt_context_get_generic_excode(int rc, char *buf, size_t bufsz, const char *fmt, ...)
+{
+	va_list va;
+
+	if (rc == 0)
+		return MNT_EX_SUCCESS;
+
+	va_start(va, fmt);
+
+	/* we need to support "%m" */
+	errno = rc < 0 ? -rc : rc;
+
+	if (buf && bufsz && vsnprintf(buf, bufsz, fmt, va) < 0)
+		*buf = '\0';
+
+	switch (errno) {
+	case EINVAL:
+	case EPERM:
+		rc = MNT_EX_USAGE;
+		break;
+	case ENOMEM:
+		rc = MNT_EX_SYSERR;
+		break;
+	default:
+		rc = MNT_EX_FAIL;
+		break;
+	}
+	va_end(va);
+	return rc;
+}
+
+/**
+ * mnt_context_get_excode:
+ * @cxt: context
+ * @rc: return code of the previous operation
+ * @buf: buffer to print error message (optional)
+ * @bufsz: size of the buffer
+ *
+ * This function analyzes context, [u]mount syscall and external helper status
+ * and @mntrc and generates unified return code (see MNT_EX_*) as expected
+ * from mount(8) or umount(8).
+ *
+ * If the external helper (e.g. /sbin/mount.type) has been executed than it
+ * returns status from wait() of the helper. It's not libmount fail if helper
+ * returns some crazy undocumented codes...  See mnt_context_helper_executed()
+ * and mnt_context_get_helper_status(). Note that mount(8) and umount(8) utils
+ * always return code from helper without extra care about it.
+ *
+ * The current implementation does not read error message from external
+ * helper into @buf.
+ *
+ * If the argument @buf is not NULL then error message is generated (if
+ * anything failed).
+ *
+ * The @mntrc is usually return code from mnt_context_mount(),
+ * mnt_context_umount(), or 'mntrc' as returned by mnt_context_next_mount().
+ *
+ * Since: 2.30
+ *
+ * Returns: MNT_EX_* codes.
+ */
+int mnt_context_get_excode(
+			struct libmnt_context *cxt,
+			int rc,
+			char *buf,
+			size_t bufsz)
+{
+	if (buf) {
+		*buf = '\0'; /* for sure */
+
+		if (!cxt->enabled_textdomain) {
+			bindtextdomain(LIBMOUNT_TEXTDOMAIN, LOCALEDIR);
+			cxt->enabled_textdomain = 1;
+		}
+	}
+
+	switch (cxt->action) {
+	case MNT_ACT_MOUNT:
+		rc = mnt_context_get_mount_excode(cxt, rc, buf, bufsz);
+		break;
+	case MNT_ACT_UMOUNT:
+		rc = mnt_context_get_umount_excode(cxt, rc, buf, bufsz);
+		break;
+	default:
+		if (rc)
+			rc = mnt_context_get_generic_excode(rc, buf, bufsz,
+				_("operation failed: %m"));
+		else
+			rc = MNT_EX_SUCCESS;
+		break;
+	}
+
+	DBG(CXT, ul_debugobj(cxt, "excode: rc=%d message=\"%s\"", rc,
+				buf ? buf : "<no-message>"));
+	return rc;
+}
+
+
+/**
+ * mnt_context_init_helper
+ * @cxt: mount context
+ * @action: MNT_ACT_{UMOUNT,MOUNT}
+ * @flags: not used now
+ *
+ * This function informs libmount that used from [u]mount.type helper.
+ *
+ * The function also calls mnt_context_disable_helpers() to avoid recursive
+ * mount.type helpers calling. It you really want to call another
+ * mount.type helper from your helper, then you have to explicitly enable this
+ * feature by:
+ *
+ *	 mnt_context_disable_helpers(cxt, FALSE);
+ *
+ * Returns: 0 on success, negative number in case of error.
+ */
+int mnt_context_init_helper(struct libmnt_context *cxt, int action,
+			    int flags __attribute__((__unused__)))
+{
+	int rc;
+
+	if (!cxt)
+		return -EINVAL;
+
+	rc = mnt_context_disable_helpers(cxt, TRUE);
+	if (!rc)
+		rc = set_flag(cxt, MNT_FL_HELPER, 1);
+	if (!rc)
+		cxt->action = action;
+
+	DBG(CXT, ul_debugobj(cxt, "initialized for [u]mount.<type> helper [rc=%d]", rc));
+	return rc;
+}
+
+/**
+ * mnt_context_helper_setopt:
+ * @cxt: context
+ * @c: getopt() result
+ * @arg: getopt() optarg
+ *
+ * This function applies the [u]mount.type command line option (for example parsed
+ * by getopt or getopt_long) to @cxt. All unknown options are ignored and
+ * then 1 is returned.
+ *
+ * Returns: negative number on error, 1 if @c is unknown option, 0 on success.
+ */
+int mnt_context_helper_setopt(struct libmnt_context *cxt, int c, char *arg)
+{
+	if (cxt) {
+		switch(cxt->action) {
+		case MNT_ACT_MOUNT:
+			return mnt_context_mount_setopt(cxt, c, arg);
+		case MNT_ACT_UMOUNT:
+			return mnt_context_umount_setopt(cxt, c, arg);
+		}
+	}
+	return -EINVAL;
+}
+
+/**
+ * mnt_context_is_fs_mounted:
+ * @cxt: context
+ * @fs: filesystem
+ * @mounted: returns 1 for mounted and 0 for non-mounted filesystems
+ *
+ * Please, read the mnt_table_is_fs_mounted() description!
+ *
+ * Returns: 0 on success and negative number in case of error.
+ */
+int mnt_context_is_fs_mounted(struct libmnt_context *cxt,
+			      struct libmnt_fs *fs, int *mounted)
+{
+	struct libmnt_table *mountinfo, *orig;
+	int rc = 0;
+	struct libmnt_ns *ns_old;
+
+	if (!cxt || !fs || !mounted)
+		return -EINVAL;
+
+	ns_old = mnt_context_switch_target_ns(cxt);
+	if (!ns_old)
+		return -MNT_ERR_NAMESPACE;
+
+	orig = cxt->mountinfo;
+	rc = mnt_context_get_mountinfo(cxt, &mountinfo);
+	if (rc == -ENOENT && mnt_fs_streq_target(fs, "/proc")) {
+		if (!orig) {
+			mnt_unref_table(cxt->mountinfo);
+			cxt->mountinfo = NULL;
+		}
+		*mounted = 0;
+		rc = 0;			/* /proc not mounted */
+
+	} else if (rc == 0) {
+		*mounted = __mnt_table_is_fs_mounted(mountinfo, fs,
+				mnt_context_get_target_prefix(cxt));
+
+	}
+
+	if (!mnt_context_switch_ns(cxt, ns_old))
+		return -MNT_ERR_NAMESPACE;
+	return rc;
+}
+
+static int mnt_context_add_child(struct libmnt_context *cxt, pid_t pid)
+{
+	pid_t *pids;
+
+	if (!cxt)
+		return -EINVAL;
+
+	pids = realloc(cxt->children, sizeof(pid_t) * cxt->nchildren + 1);
+	if (!pids)
+		return -ENOMEM;
+
+	DBG(CXT, ul_debugobj(cxt, "add new child %d", pid));
+	cxt->children = pids;
+	cxt->children[cxt->nchildren++] = pid;
+
+	return 0;
+}
+
+int mnt_fork_context(struct libmnt_context *cxt)
+{
+	int rc = 0;
+	pid_t pid;
+
+	assert(cxt);
+	if (!mnt_context_is_parent(cxt))
+		return -EINVAL;
+
+	DBG(CXT, ul_debugobj(cxt, "forking context"));
+
+	DBG_FLUSH;
+
+	pid = fork();
+
+	switch (pid) {
+	case -1: /* error */
+		DBG(CXT, ul_debugobj(cxt, "fork failed %m"));
+		return -errno;
+
+	case 0: /* child */
+		cxt->pid = getpid();
+		mnt_context_enable_fork(cxt, FALSE);
+		DBG(CXT, ul_debugobj(cxt, "child created"));
+		break;
+
+	default:
+		rc = mnt_context_add_child(cxt, pid);
+		break;
+	}
+
+	return rc;
+}
+
+int mnt_context_wait_for_children(struct libmnt_context *cxt,
+				  int *nchildren, int *nerrs)
+{
+	int i;
+
+	if (!cxt)
+		return -EINVAL;
+
+	assert(mnt_context_is_parent(cxt));
+
+	for (i = 0; i < cxt->nchildren; i++) {
+		pid_t pid = cxt->children[i];
+		int rc = 0, ret = 0;
+
+		if (!pid)
+			continue;
+		do {
+			DBG(CXT, ul_debugobj(cxt,
+					"waiting for child (%d/%d): %d",
+					i + 1, cxt->nchildren, pid));
+			errno = 0;
+			rc = waitpid(pid, &ret, 0);
+
+		} while (rc == -1 && errno == EINTR);
+
+		if (nchildren)
+			(*nchildren)++;
+
+		if (rc != -1 && nerrs) {
+			if (WIFEXITED(ret))
+				(*nerrs) += WEXITSTATUS(ret) == 0 ? 0 : 1;
+			else
+				(*nerrs)++;
+		}
+		cxt->children[i] = 0;
+	}
+
+	cxt->nchildren = 0;
+	free(cxt->children);
+	cxt->children = NULL;
+	return 0;
+}
+
+static void close_ns(struct libmnt_ns *ns)
+{
+	if (ns->fd == -1)
+		return;
+
+	close(ns->fd);
+	ns->fd = -1;
+
+	mnt_unref_cache(ns->cache);
+	ns->cache = NULL;
+}
+
+/**
+ * mnt_context_set_target_ns:
+ * @cxt: mount context
+ * @path: path to target namespace or NULL
+ *
+ * Sets target namespace to namespace represented by @path. If @path is NULL,
+ * target namespace is cleared.
+ *
+ * This function sets errno to ENOSYS and returns error if libmount is
+ * compiled without namespaces support.
+ *
+ * Returns: 0 on success, negative number in case of error.
+ *
+ * Since: 2.33
+ */
+int mnt_context_set_target_ns(struct libmnt_context *cxt, const char *path)
+{
+	if (!cxt)
+		return -EINVAL;
+
+	DBG(CXT, ul_debugobj(cxt, "Setting %s as target namespace", path));
+
+	/* cleanup only */
+	if (!path) {
+		close_ns(&cxt->ns_orig);
+		close_ns(&cxt->ns_tgt);
+		return 0;
+	}
+
+#ifdef USE_LIBMOUNT_SUPPORT_NAMESPACES
+	int errsv = 0;
+	int tmp;
+
+	errno = 0;
+
+	/* open original namespace */
+	if (cxt->ns_orig.fd == -1) {
+		cxt->ns_orig.fd = open("/proc/self/ns/mnt", O_RDONLY | O_CLOEXEC);
+		if (cxt->ns_orig.fd == -1)
+			return -errno;
+		cxt->ns_orig.cache = NULL;
+	}
+
+	/* open target (wanted) namespace */
+	tmp = open(path, O_RDONLY | O_CLOEXEC);
+	if (tmp == -1)
+		return -errno;
+
+	/* test whether namespace switching works */
+	DBG(CXT, ul_debugobj(cxt, "Trying whether namespace is valid"));
+	if (setns(tmp, CLONE_NEWNS)
+	    || setns(cxt->ns_orig.fd, CLONE_NEWNS)) {
+		errsv = errno;
+		DBG(CXT, ul_debugobj(cxt, "setns(2) failed [errno=%d %m]", errno));
+		goto err;
+	}
+
+	close_ns(&cxt->ns_tgt);
+
+	cxt->ns_tgt.fd = tmp;
+	cxt->ns_tgt.cache = NULL;
+
+	return 0;
+err:
+	close(tmp);
+	errno = errsv;
+
+#else /* ! USE_LIBMOUNT_SUPPORT_NAMESPACES */
+	errno = ENOSYS;
+#endif
+	return -errno;
+}
+
+/**
+ * mnt_context_get_target_ns:
+ * @cxt: mount context
+ *
+ * Returns: pointer to target namespace
+ *
+ * Since: 2.33
+ */
+struct libmnt_ns *mnt_context_get_target_ns(struct libmnt_context *cxt)
+{
+	return &cxt->ns_tgt;
+}
+
+/**
+ * mnt_context_get_origin_ns:
+ * @cxt: mount context
+ *
+ * Returns: pointer to original namespace
+ *
+ * Since: 2.33
+ */
+struct libmnt_ns *mnt_context_get_origin_ns(struct libmnt_context *cxt)
+{
+	return &cxt->ns_orig;
+}
+
+
+/**
+ * mnt_context_switch_ns:
+ * @cxt: mount context
+ * @ns: namespace to switch to
+ *
+ * Switch to namespace specified by ns
+ *
+ * Typical usage:
+ * <informalexample>
+ *   <programlisting>
+ *	struct libmnt_ns *ns_old;
+ *	ns_old = mnt_context_switch_ns(cxt, mnt_context_get_target_ns(cxt));
+ *	... code ...
+ *	mnt_context_switch_ns(cxt, ns_old);
+ *   </programlisting>
+ * </informalexample>
+ *
+ * Returns: pointer to previous namespace or NULL on error
+ *
+ * Since: 2.33
+ */
+struct libmnt_ns *mnt_context_switch_ns(struct libmnt_context *cxt, struct libmnt_ns *ns)
+{
+	struct libmnt_ns *old = NULL;
+
+	if (!cxt || !ns)
+		return NULL;
+
+	/*
+	 * If mnt_context_set_target_ns() has never been used than @ns file
+	 * descriptor is -1 and this function is noop.
+	 */
+	old = cxt->ns_cur;
+	if (ns == old || ns->fd == -1)
+		return old;
+
+#ifdef USE_LIBMOUNT_SUPPORT_NAMESPACES
+	/* remember the current cache */
+	if (old->cache != cxt->cache) {
+		mnt_unref_cache(old->cache);
+		old->cache = cxt->cache;
+		mnt_ref_cache(old->cache);
+	}
+
+	/* switch */
+	DBG(CXT, ul_debugobj(cxt, "Switching to %s namespace",
+		ns == mnt_context_get_target_ns(cxt) ? "target" :
+		ns == mnt_context_get_origin_ns(cxt) ? "original" : "other"));
+
+	if (setns(ns->fd, CLONE_NEWNS)) {
+		int errsv = errno;
+
+		DBG(CXT, ul_debugobj(cxt, "setns(2) failed [errno=%d %m]", errno));
+		errno = errsv;
+		return NULL;
+	}
+
+	/* update pointer to the current namespace */
+	cxt->ns_cur = ns;
+
+	/* update pointer to the cache */
+	mnt_unref_cache(cxt->cache);
+	cxt->cache = ns->cache;
+	mnt_ref_cache(cxt->cache);
+#endif /* USE_LIBMOUNT_SUPPORT_NAMESPACES */
+
+	return old;
+}
+
+/**
+ * mnt_context_switch_origin_ns:
+ * @cxt: mount context
+ *
+ * Switch to original namespace
+ *
+ * This is shorthand for
+ * <informalexample>
+ *   <programlisting>
+ *	mnt_context_switch_ns(cxt, mnt_context_get_origin_ns(cxt));
+ *   </programlisting>
+ * </informalexample>
+ *
+ * Returns: pointer to previous namespace or NULL on error
+ *
+ * Since: 2.33
+ */
+struct libmnt_ns *mnt_context_switch_origin_ns(struct libmnt_context *cxt)
+{
+	return mnt_context_switch_ns(cxt, mnt_context_get_origin_ns(cxt));
+}
+
+/**
+ * mnt_context_switch_target_ns:
+ * @cxt: mount context
+ *
+ * Switch to target namespace
+ *
+ * This is shorthand for
+ * <informalexample>
+ *   <programlisting>
+ *	mnt_context_switch_ns(cxt, mnt_context_get_target_ns(cxt));
+ *   </programlisting>
+ * </informalexample>
+ *
+ * Returns: pointer to previous namespace or NULL on error
+ *
+ * Since: 2.33
+ */
+struct libmnt_ns *mnt_context_switch_target_ns(struct libmnt_context *cxt)
+{
+	return mnt_context_switch_ns(cxt, mnt_context_get_target_ns(cxt));
+}
+
+
+#ifdef TEST_PROGRAM
+
+static int test_search_helper(struct libmnt_test *ts, int argc, char *argv[])
+{
+	struct libmnt_context *cxt;
+	const char *type;
+	int rc;
+
+	if (argc < 2)
+		return -EINVAL;
+
+	cxt = mnt_new_context();
+	if (!cxt)
+		return -ENOMEM;
+
+	type = argv[1];
+
+	mnt_context_get_fs(cxt);		/* just to fill cxt->fs */
+	cxt->flags |= MNT_FL_MOUNTFLAGS_MERGED;	/* fake */
+
+	rc = mnt_context_prepare_helper(cxt, "mount", type);
+	printf("helper is: %s\n", cxt->helper ? cxt->helper : "not found");
+
+	mnt_free_context(cxt);
+	return rc;
+}
+
+
+static struct libmnt_lock *lock;
+
+static void lock_fallback(void)
+{
+	if (lock)
+		mnt_unlock_file(lock);
+}
+
+static int test_mount(struct libmnt_test *ts, int argc, char *argv[])
+{
+	int idx = 1, rc = 0;
+	struct libmnt_context *cxt;
+
+	if (argc < 2)
+		return -EINVAL;
+
+	cxt = mnt_new_context();
+	if (!cxt)
+		return -ENOMEM;
+
+	if (!strcmp(argv[idx], "-o")) {
+		mnt_context_set_options(cxt, argv[idx + 1]);
+		idx += 2;
+	}
+	if (!strcmp(argv[idx], "-t")) {
+		/* TODO: use mnt_context_set_fstype_pattern() */
+		mnt_context_set_fstype(cxt, argv[idx + 1]);
+		idx += 2;
+	}
+
+	if (argc == idx + 1)
+		/* mount <mountpoint>|<device> */
+		mnt_context_set_target(cxt, argv[idx++]);
+
+	else if (argc == idx + 2) {
+		/* mount <device> <mountpoint> */
+		mnt_context_set_source(cxt, argv[idx++]);
+		mnt_context_set_target(cxt, argv[idx++]);
+	}
+
+	/* this is unnecessary! -- libmount is able to internally
+	 * create and manage the lock
+	 */
+	lock = mnt_context_get_lock(cxt);
+	if (lock)
+		atexit(lock_fallback);
+
+	rc = mnt_context_mount(cxt);
+	if (rc)
+		warn("failed to mount");
+	else
+		printf("successfully mounted\n");
+
+	lock = NULL;	/* because we use atexit lock_fallback */
+	mnt_free_context(cxt);
+	return rc;
+}
+
+static int test_umount(struct libmnt_test *ts, int argc, char *argv[])
+{
+	int idx = 1, rc = 0;
+	struct libmnt_context *cxt;
+
+	if (argc < 2)
+		return -EINVAL;
+
+	cxt = mnt_new_context();
+	if (!cxt)
+		return -ENOMEM;
+
+	if (!strcmp(argv[idx], "-t")) {
+		mnt_context_set_fstype(cxt, argv[idx + 1]);
+		idx += 2;
+	}
+
+	if (!strcmp(argv[idx], "-f")) {
+		mnt_context_enable_force(cxt, TRUE);
+		idx++;
+	}
+
+	if (!strcmp(argv[idx], "-l")) {
+		mnt_context_enable_lazy(cxt, TRUE);
+		idx++;
+	}
+
+	if (!strcmp(argv[idx], "-r")) {
+		mnt_context_enable_rdonly_umount(cxt, TRUE);
+		idx++;
+	}
+
+	if (argc == idx + 1) {
+		/* mount <mountpoint>|<device> */
+		mnt_context_set_target(cxt, argv[idx++]);
+	} else {
+		rc = -EINVAL;
+		goto err;
+	}
+
+	lock = mnt_context_get_lock(cxt);
+	if (lock)
+		atexit(lock_fallback);
+
+	rc = mnt_context_umount(cxt);
+	if (rc)
+		printf("failed to umount\n");
+	else
+		printf("successfully umounted\n");
+err:
+	lock = NULL;	/* because we use atexit lock_fallback */
+	mnt_free_context(cxt);
+	return rc;
+}
+
+static int test_flags(struct libmnt_test *ts, int argc, char *argv[])
+{
+	int idx = 1, rc = 0;
+	struct libmnt_context *cxt;
+	const char *opt = NULL;
+	unsigned long flags = 0;
+
+	if (argc < 2)
+		return -EINVAL;
+
+	cxt = mnt_new_context();
+	if (!cxt)
+		return -ENOMEM;
+
+	if (!strcmp(argv[idx], "-o")) {
+		mnt_context_set_options(cxt, argv[idx + 1]);
+		idx += 2;
+	}
+
+	if (argc == idx + 1)
+		/* mount <mountpoint>|<device> */
+		mnt_context_set_target(cxt, argv[idx++]);
+
+	rc = mnt_context_prepare_mount(cxt);
+	if (rc)
+		printf("failed to prepare mount %s\n", strerror(-rc));
+
+	opt = mnt_fs_get_options(cxt->fs);
+	if (opt)
+		fprintf(stdout, "options: %s\n", opt);
+
+	mnt_context_get_mflags(cxt, &flags);
+	fprintf(stdout, "flags: %08lx\n", flags);
+
+	mnt_free_context(cxt);
+	return rc;
+}
+
+static int test_cxtsync(struct libmnt_test *ts, int argc, char *argv[])
+{
+	struct libmnt_context *cxt;
+	struct libmnt_fs *fs;
+	unsigned long flags = 0;
+	int rc;
+
+	if (argc != 4)
+		return -EINVAL;
+
+	fs = mnt_new_fs();
+	if (!fs)
+		return -ENOMEM;
+
+	rc = mnt_fs_set_options(fs, argv[1]);
+	if (rc)
+		return rc;
+
+	cxt = mnt_new_context();
+	if (!cxt)
+		return -ENOMEM;
+
+	rc = mnt_context_set_fs(cxt, fs);
+	if (rc)
+		return rc;
+
+	rc = mnt_context_append_options(cxt, argv[2]);
+	if (rc)
+		return rc;
+
+	rc = mnt_fs_append_options(fs, argv[3]);
+	if (rc)
+		return rc;
+
+	mnt_context_get_mflags(cxt, &flags);
+
+	printf("     fs options: %s\n", mnt_fs_get_options(fs));
+	printf("context options: %s\n", mnt_context_get_options(cxt));
+	printf(" context mflags: %08lx\n", flags);
+
+	mnt_free_context(cxt);
+	return 0;
+}
+
+static int test_mountall(struct libmnt_test *ts, int argc, char *argv[])
+{
+	struct libmnt_context *cxt;
+	struct libmnt_iter *itr;
+	struct libmnt_fs *fs;
+	int mntrc, ignored, idx = 1;
+
+	cxt = mnt_new_context();
+	itr = mnt_new_iter(MNT_ITER_FORWARD);
+
+	if (!cxt || !itr)
+		return -ENOMEM;
+
+	if (argc > 2) {
+		if (argv[idx] && !strcmp(argv[idx], "-O")) {
+			mnt_context_set_options_pattern(cxt, argv[idx + 1]);
+			idx += 2;
+		}
+		if (argv[idx] && !strcmp(argv[idx], "-t")) {
+			mnt_context_set_fstype_pattern(cxt, argv[idx + 1]);
+			idx += 2;
+		}
+	}
+
+	while (mnt_context_next_mount(cxt, itr, &fs, &mntrc, &ignored) == 0) {
+
+		const char *tgt = mnt_fs_get_target(fs);
+
+		if (ignored == 1)
+			printf("%s: ignored: not match\n", tgt);
+		else if (ignored == 2)
+			printf("%s: ignored: already mounted\n", tgt);
+
+		else if (!mnt_context_get_status(cxt)) {
+			if (mntrc > 0) {
+				errno = mntrc;
+				warn("%s: mount failed", tgt);
+			} else
+				warnx("%s: mount failed", tgt);
+		} else
+			printf("%s: successfully mounted\n", tgt);
+	}
+
+	mnt_free_context(cxt);
+	return 0;
+}
+
+
+
+int main(int argc, char *argv[])
+{
+	struct libmnt_test tss[] = {
+	{ "--mount",  test_mount,  "[-o <opts>] [-t <type>] <spec>|<src> <target>" },
+	{ "--umount", test_umount, "[-t <type>] [-f][-l][-r] <src>|<target>" },
+	{ "--mount-all", test_mountall,  "[-O <pattern>] [-t <pattern] mount all filesystems from fstab" },
+	{ "--flags", test_flags,   "[-o <opts>] <spec>" },
+	{ "--cxtsync", test_cxtsync, "<fsopts> <cxtopts> <fsopts>" },
+	{ "--search-helper", test_search_helper, "<fstype>" },
+	{ NULL }};
+
+	umask(S_IWGRP|S_IWOTH);	/* to be compatible with mount(8) */
+
+	return mnt_run_test(tss, argc, argv);
+}
+
+#endif /* TEST_PROGRAM */