libmount: read optional mountinfo fields

[kzak@redhat.com: - rename struct member and functions from
                    "propagation" to "optional fields"
                  - split the original patch
                  - fix parser]

Signed-off-by: Ondrej Oprala <ondrej.oprala@gmail.com>
Signed-off-by: Karel Zak <kzak@redhat.com>

6 files changed, 26 insertions, 0 deletions

diff --git a/libmount/docs/libmount-sections.txt b/libmount/docs/libmount-sections.txt
index e0f899471..f69a63b8a 100644
--- a/libmount/docs/libmount-sections.txt
+++ b/libmount/docs/libmount-sections.txt
@@ -169,6 +169,7 @@ mnt_fs_get_fs_options
 mnt_fs_get_fstype
 mnt_fs_get_id
 mnt_fs_get_option
+mnt_fs_get_optional_fields
 mnt_fs_get_options
 mnt_fs_get_parent_id
 mnt_fs_get_passno
diff --git a/libmount/src/fs.c b/libmount/src/fs.c
index d94476870..5c1a1074a 100644
--- a/libmount/src/fs.c
+++ b/libmount/src/fs.c
@@ -691,6 +691,18 @@ const char *mnt_fs_get_options(struct libmnt_fs *fs)
 	return fs ? fs->optstr : NULL;
 }
 
+/**
+ * mnt_fs_get_optional_fields
+ * @fs: mountinfo entry pointer
+ *
+ * Returns: pointer to string with mountinfo optional fields
+ *          or NULL in case of error.
+ */
+const char *mnt_fs_get_optional_fields(struct libmnt_fs *fs)
+{
+	assert(fs);
+	return fs ? fs->opt_fields : NULL;
+}
 
 /**
  * mnt_fs_set_options:
@@ -1394,6 +1406,8 @@ int mnt_fs_print_debug(struct libmnt_fs *fs, FILE *file)
 		fprintf(file, "FS-opstr: %s\n", mnt_fs_get_fs_options(fs));
 	if (mnt_fs_get_user_options(fs))
 		fprintf(file, "user-optstr: %s\n", mnt_fs_get_user_options(fs));
+	if (mnt_fs_get_optional_fields(fs))
+		fprintf(file, "optional-fields: '%s'\n", mnt_fs_get_optional_fields(fs));
 	if (mnt_fs_get_attributes(fs))
 		fprintf(file, "attributes: %s\n", mnt_fs_get_attributes(fs));
 
diff --git a/libmount/src/libmount.h.in b/libmount/src/libmount.h.in
index 06b1595a5..b93011aa8 100644
--- a/libmount/src/libmount.h.in
+++ b/libmount/src/libmount.h.in
@@ -327,6 +327,9 @@ extern char *mnt_fs_strdup_options(struct libmnt_fs *fs)
 extern const char *mnt_fs_get_options(struct libmnt_fs *fs)
 			__ul_attribute__((nonnull))
 			__ul_attribute__((warn_unused_result));
+extern const char *mnt_fs_get_optional_fields(struct libmnt_fs *fs)
+			__ul_attribute__((nonnull))
+			__ul_attribute__((warn_unused_result));
 extern int mnt_fs_set_options(struct libmnt_fs *fs, const char *optstr);
 extern int mnt_fs_append_options(struct libmnt_fs *fs, const char *optstr);
 extern int mnt_fs_prepend_options(struct libmnt_fs *fs, const char *optstr);
diff --git a/libmount/src/libmount.sym b/libmount/src/libmount.sym
index 9e0f2c45d..ecb3e01f7 100644
--- a/libmount/src/libmount.sym
+++ b/libmount/src/libmount.sym
@@ -248,3 +248,8 @@ global:
 	mnt_table_find_devno;
 	mnt_table_parse_swaps;
 } MOUNT_2.21;
+
+MOUNT_2.23 {
+global:
+	mnt_fs_get_optional_fields;
+} MOUNT_2.22;
diff --git a/libmount/src/mountP.h b/libmount/src/mountP.h
index 5f2f780dc..edef94c1b 100644
--- a/libmount/src/mountP.h
+++ b/libmount/src/mountP.h
@@ -217,6 +217,7 @@ struct libmnt_fs {
 
 	char		*optstr;	/* fstab[4], merged options */
 	char		*vfs_optstr;	/* mountinfo[6]: fs-independent (VFS) options */
+	char		*opt_fields;	/* mountinfo[7]: optional fields */
 	char		*fs_optstr;	/* mountinfo[11]: fs-dependent options */
 	char		*user_optstr;	/* userspace mount options */
 	char		*attrs;		/* mount attributes */
diff --git a/libmount/src/tab_parse.c b/libmount/src/tab_parse.c
index 56da8ec47..a8b7b79d4 100644
--- a/libmount/src/tab_parse.c
+++ b/libmount/src/tab_parse.c
@@ -161,6 +161,8 @@ static int mnt_parse_mountinfo_line(struct libmnt_fs *fs, char *s)
 		DBG(TAB, mnt_debug("mountinfo parse error: not found separator"));
 		return -EINVAL;
 	}
+	if (p > s + 1)
+		fs->opt_fields = strndup(s + 1, p - s - 1);
 	s = p + 3;
 
 	rc += sscanf(s,	UL_SCNsA" "	/* (8) FS type */