From: Karel Zak <kzak@redhat.com>
Date: Wed, 1 Jul 2026 10:49:25 +0000 (+0200)
Subject: libmount: add mnt_table_parse_utab()
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=0926f4a70bd88beaa10cbecee58db9c28b5452d3;p=thirdparty%2Futil-linux.git

libmount: add mnt_table_parse_utab()

Add new public API to parse the utab file into a table. The utab path
and format are private library details; this function hides them from
callers. NULL as filename is recommended to let the library determine
the correct path.

This is needed by systemd for incremental fanotify-based mount
monitoring, where utab needs to be parsed independently of the full
mountinfo/listmount rescan path.

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/libmount/docs/libmount-sections.txt b/libmount/docs/libmount-sections.txt
index 8d11867aa..e9683b06f 100644
--- a/libmount/docs/libmount-sections.txt
+++ b/libmount/docs/libmount-sections.txt
@@ -418,6 +418,7 @@ mnt_table_parse_fstab
 mnt_table_parse_mtab
 mnt_table_parse_stream
 mnt_table_parse_swaps
+mnt_table_parse_utab
 mnt_table_remove_fs
 mnt_table_set_cache
 mnt_table_set_intro_comment
diff --git a/libmount/src/libmount.h.in b/libmount/src/libmount.h.in
index d3b39e661..ca9a1ad23 100644
--- a/libmount/src/libmount.h.in
+++ b/libmount/src/libmount.h.in
@@ -608,6 +608,7 @@ extern int mnt_table_parse_dir(struct libmnt_table *tb, const char *dirname);
 extern int mnt_table_parse_fstab(struct libmnt_table *tb, const char *filename);
 extern int mnt_table_parse_swaps(struct libmnt_table *tb, const char *filename);
 extern int mnt_table_parse_mtab(struct libmnt_table *tb, const char *filename);
+extern int mnt_table_parse_utab(struct libmnt_table *tb, const char *filename);
 extern int mnt_table_disable_useropts(struct libmnt_table *tb, int disable);
 extern int mnt_table_set_parser_errcb(struct libmnt_table *tb,
                 int (*cb)(struct libmnt_table *tb, const char *filename, int line));
diff --git a/libmount/src/libmount.sym b/libmount/src/libmount.sym
index 0240b5fe0..de757eda4 100644
--- a/libmount/src/libmount.sym
+++ b/libmount/src/libmount.sym
@@ -424,4 +424,5 @@ MOUNT_2_42 {
 
 MOUNT_2_43 {
 	mnt_table_disable_useropts;
+	mnt_table_parse_utab;
 } MOUNT_2_42;
diff --git a/libmount/src/tab_parse.c b/libmount/src/tab_parse.c
index c21d5d019..99d440cf8 100644
--- a/libmount/src/tab_parse.c
+++ b/libmount/src/tab_parse.c
@@ -1155,6 +1155,32 @@ int mnt_table_parse_swaps(struct libmnt_table *tb, const char *filename)
 	return mnt_table_parse_file(tb, filename);
 }
 
+/**
+ * mnt_table_parse_utab:
+ * @tb: table
+ * @filename: overwrites default or NULL (recommended)
+ *
+ * This function parses the utab file and appends new lines to the @tb. The utab
+ * is a private libmount file that stores userspace mount options. The file
+ * location and format are library implementation details and subject to change;
+ * use NULL as @filename to let the library determine the correct path.
+ *
+ * Returns: 0 on success or negative number in case of error.
+ */
+int mnt_table_parse_utab(struct libmnt_table *tb, const char *filename)
+{
+	if (!tb)
+		return -EINVAL;
+	if (!filename)
+		filename = mnt_get_utab_path();
+	if (!filename || is_file_empty(filename))
+		return 0;
+
+	tb->fmt = MNT_FMT_UTAB;
+
+	return mnt_table_parse_file(tb, filename);
+}
+
 /**
  * mnt_table_parse_fstab:
  * @tb: table