From: Karel Zak <kzak@redhat.com>
Date: Thu, 6 Oct 2022 10:02:41 +0000 (+0200)
Subject: libmount: fix mount -a to work with optlist
X-Git-Tag: v2.39-rc1~242
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=01790c7d6d418b440961a769f191338e37f0df62;p=thirdparty%2Futil-linux.git

libmount: fix mount -a to work with optlist

The original code uses libmnt_fs instance to store mount options. The
new uses libmnt_fs only for library API backward compatibility, but
internally it uses libmnt_optlist. Let's use optlist also to save
context template.

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

diff --git a/libmount/src/context.c b/libmount/src/context.c
index e602ce54bc..3551b0d77b 100644
--- a/libmount/src/context.c
+++ b/libmount/src/context.c
@@ -102,7 +102,8 @@ void mnt_free_context(struct libmnt_context *cxt)
 	mnt_unref_table(cxt->fstab);
 	mnt_unref_cache(cxt->cache);
 	mnt_unref_fs(cxt->fs);
-	mnt_unref_fs(cxt->fs_template);
+
+	mnt_unref_optlist(cxt->optlist_saved);
 	mnt_unref_optlist(cxt->optlist);
 
 	mnt_free_lock(cxt->lock);
@@ -152,11 +153,13 @@ int mnt_reset_context(struct libmnt_context *cxt)
 	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;
@@ -194,7 +197,7 @@ int mnt_reset_context(struct libmnt_context *cxt)
 }
 
 /*
- * Saves the current context FS setting (mount options, etc) to make it usable after
+ * 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.
@@ -203,21 +206,17 @@ int mnt_reset_context(struct libmnt_context *cxt)
  */
 int mnt_context_save_template(struct libmnt_context *cxt)
 {
-	struct libmnt_fs *fs = NULL;
-
 	if (!cxt)
 		return -EINVAL;
 
-	DBG(CXT, ul_debugobj(cxt, "save FS as template"));
+	DBG(CXT, ul_debugobj(cxt, "saving template"));
 
-	if (cxt->fs) {
-		fs = mnt_copy_fs(NULL, cxt->fs);
-		if (!fs)
-			return -ENOMEM;
-	}
+	/* reset old saved data */
+	mnt_unref_optlist(cxt->optlist_saved);
+	cxt->optlist_saved = NULL;
 
-	mnt_unref_fs(cxt->fs_template);
-	cxt->fs_template = fs;
+	if (cxt->optlist)
+		cxt->optlist_saved = mnt_copy_optlist(cxt->optlist);
 
 	return 0;
 }
@@ -230,31 +229,22 @@ int mnt_context_save_template(struct libmnt_context *cxt)
  */
 int mnt_context_apply_template(struct libmnt_context *cxt)
 {
-	struct libmnt_fs *fs = NULL;
-	int rc = 0;
-
 	if (!cxt)
 		return -EINVAL;
 
-	if (cxt->fs_template) {
-		DBG(CXT, ul_debugobj(cxt, "copy FS from template"));
-		fs = mnt_copy_fs(NULL, cxt->fs_template);
-		if (!fs)
-			return -ENOMEM;
-		rc = mnt_context_set_fs(cxt, fs);
-		mnt_unref_fs(fs);
-	} else {
-		DBG(CXT, ul_debugobj(cxt, "no FS template, reset only"));
-		mnt_unref_fs(cxt->fs);
-		cxt->fs = NULL;
-	}
+	DBG(CXT, ul_debugobj(cxt, "restoring template"));
+	mnt_unref_optlist(cxt->optlist);
+	cxt->optlist = NULL;
 
-	return rc;
+	if (cxt->optlist_saved)
+		cxt->optlist = mnt_copy_optlist(cxt->optlist_saved);
+
+	return 0;
 }
 
 int mnt_context_has_template(struct libmnt_context *cxt)
 {
-	return cxt && cxt->fs_template ? 1 : 0;
+	return cxt && cxt->optlist_saved ? 1 : 0;
 }
 
 struct libmnt_context *mnt_copy_context(struct libmnt_context *o)
@@ -1163,13 +1153,10 @@ int mnt_context_append_options(struct libmnt_context *cxt, const char *optstr)
  */
 const char *mnt_context_get_options(struct libmnt_context *cxt)
 {
-	struct libmnt_optlist *ls = mnt_context_get_optlist(cxt);
 	const char *str = NULL;
 
-	if (!ls)
-		return NULL;
-
-	mnt_optlist_get_optstr(ls, &str, NULL, 0);
+	if (cxt->optlist && !mnt_optlist_is_empty(cxt->optlist))
+		mnt_optlist_get_optstr(cxt->optlist, &str, NULL, 0);
 	return str;
 }
 
@@ -2199,6 +2186,8 @@ static int apply_fs(struct libmnt_context *cxt, struct libmnt_fs *fs, unsigned l
 	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!"));
@@ -2210,6 +2199,9 @@ static int apply_fs(struct libmnt_context *cxt, struct libmnt_fs *fs, unsigned l
 
 	}
 
+	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",
diff --git a/libmount/src/mountP.h b/libmount/src/mountP.h
index 3345a14dec..e6ac6b6651 100644
--- a/libmount/src/mountP.h
+++ b/libmount/src/mountP.h
@@ -371,7 +371,6 @@ struct libmnt_context
 	char	*optstr_pattern;	/* for mnt_match_options() */
 
 	struct libmnt_fs *fs;		/* filesystem description (type, mountpoint, device, ...) */
-	struct libmnt_fs *fs_template;	/* used for @fs on mnt_reset_context() */
 
 	struct libmnt_table *fstab;	/* fstab entries */
 	struct libmnt_table *mountinfo;	/* already mounted filesystems */
@@ -393,7 +392,9 @@ struct libmnt_context
 	struct libmnt_cache	*cache;		/* paths cache */
 	struct libmnt_lock	*lock;		/* utab lock */
 	struct libmnt_update	*update;	/* utab update */
+
 	struct libmnt_optlist	*optlist;	/* parsed mount options */
+	struct libmnt_optlist	*optlist_saved;	/* save/apply context template */
 
 	const struct libmnt_optmap *map_linux;		/* system options map */
 	const struct libmnt_optmap *map_userspace;	/* userspace options map */
@@ -484,6 +485,8 @@ struct libmnt_optlist;
 extern struct libmnt_optlist *mnt_new_optlist(void);
 extern void mnt_ref_optlist(struct libmnt_optlist *ls);
 extern void mnt_unref_optlist(struct libmnt_optlist *ls);
+extern struct libmnt_optlist *mnt_copy_optlist(struct libmnt_optlist *ls);
+extern int mnt_optlist_is_empty(struct libmnt_optlist *ls);
 extern unsigned int mnt_optlist_get_age(struct libmnt_optlist *ls);
 extern int mnt_optlist_register_map(struct libmnt_optlist *ls, const struct libmnt_optmap *map);
 extern int mnt_optlist_remove_opt(struct libmnt_optlist *ls, struct libmnt_opt *opt);
diff --git a/libmount/src/optlist.c b/libmount/src/optlist.c
index edb9594912..7b4033aaa7 100644
--- a/libmount/src/optlist.c
+++ b/libmount/src/optlist.c
@@ -918,6 +918,48 @@ int mnt_optlist_get_optstr(struct libmnt_optlist *ls, const char **optstr,
 	return 0;
 }
 
+struct libmnt_optlist *mnt_copy_optlist(struct libmnt_optlist *ls)
+{
+	struct libmnt_optlist *n = mnt_new_optlist();
+	struct libmnt_iter itr;
+	struct libmnt_opt *opt;
+	size_t i;
+
+	if (!n)
+		return NULL;
+
+	n->age = ls->age;
+	n->linux_map = ls->linux_map;
+
+	for (i = 0; i < ls->nmaps; i++)
+		n->maps[i] = ls->maps[i];
+	n->nmaps = ls->nmaps;
+
+	mnt_reset_iter(&itr, MNT_ITER_FORWARD);
+
+	while (mnt_optlist_next_opt(ls, &itr, &opt) == 0) {
+		struct libmnt_opt *no;
+
+		no = optlist_new_opt(n,
+			opt->name, opt->name ? strlen(opt->name) : 0,
+			opt->value, opt->value ? strlen(opt->value) : 0,
+			opt->map, opt->ent, NULL);
+		if (no) {
+			no->src = opt->src;
+			no->external = opt->external;
+		}
+	}
+
+	n->merged = ls->merged;
+	return n;
+}
+
+
+int mnt_optlist_is_empty(struct libmnt_optlist *ls)
+{
+	return ls == NULL || list_empty(&ls->opts);
+}
+
 unsigned int mnt_optlist_get_age(struct libmnt_optlist *ls)
 {
 	return ls ? ls->age : 0;