autofs-5.1.7 - add tree_mapent_add_node()

From: Ian Kent <raven@themaw.net>

Add function tree_mapent_add_node() to the mapent tree handling
implementation.

Signed-off-by: Ian Kent <raven@themaw.net>
---
 CHANGELOG           |    1 +
 include/automount.h |    1 +
 include/mounts.h    |    1 +
 lib/cache.c         |    5 ++---
 lib/mounts.c        |   47 +++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 52 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG b/CHANGELOG
index 8841f72f..85730eda 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -33,6 +33,7 @@
 - add a len field to struct autofs_point.
 - make tree implementation data independent.
 - add mapent tree implementation.
+- add tree_mapent_add_node().
 
 25/01/2021 autofs-5.1.7
 - make bind mounts propagation slave by default.
diff --git a/include/automount.h b/include/automount.h
index ebc2007f..f6023e27 100644
--- a/include/automount.h
+++ b/include/automount.h
@@ -216,6 +216,7 @@ int cache_add(struct mapent_cache *mc, struct map_source *ms, const char *key, c
 int cache_update_offset(struct mapent_cache *mc, const char *mkey, const char *key, const char *mapent, time_t age);
 int cache_lookup_negative(struct mapent *me, const char *key);
 void cache_update_negative(struct mapent_cache *mc, struct map_source *ms, const char *key, time_t timeout);
+struct mapent *cache_get_offset_parent(struct mapent_cache *mc, const char *key);
 int cache_set_offset_parent(struct mapent_cache *mc, const char *offset);
 int cache_update(struct mapent_cache *mc, struct map_source *ms, const char *key, const char *mapent, time_t age);
 int cache_delete(struct mapent_cache *mc, const char *key);
diff --git a/include/mounts.h b/include/mounts.h
index fd7c6183..a0e60e24 100644
--- a/include/mounts.h
+++ b/include/mounts.h
@@ -169,6 +169,7 @@ void mnts_get_expire_list(struct list_head *mnts, struct autofs_point *ap);
 void mnts_put_expire_list(struct list_head *mnts);
 void mnts_set_mounted_mount(struct autofs_point *ap, const char *name, unsigned int flags);
 struct tree_node *tree_mapent_root(struct mapent *me);
+int tree_mapent_add_node(struct mapent_cache *mc, const char *base, const char *key);
 int unlink_mount_tree(struct autofs_point *ap, const char *mp);
 void free_mnt_list(struct mnt_list *list);
 int is_mounted(const char *mp, unsigned int type);
diff --git a/lib/cache.c b/lib/cache.c
index 6dfaeff5..7c409a56 100644
--- a/lib/cache.c
+++ b/lib/cache.c
@@ -749,8 +749,7 @@ void cache_update_negative(struct mapent_cache *mc,
 }
 
 
-static struct mapent *get_offset_parent(struct mapent_cache *mc,
-					const char *key)
+struct mapent *cache_get_offset_parent(struct mapent_cache *mc, const char *key)
 {
 	struct mapent *me;
 	char *parent, *tail;
@@ -796,7 +795,7 @@ int cache_set_offset_parent(struct mapent_cache *mc, const char *offset)
 	if (!IS_MM(this))
 		return 0;
 
-	parent = get_offset_parent(mc, offset);
+	parent = cache_get_offset_parent(mc, offset);
 	if (parent)
 		this->parent = parent;
 	else
diff --git a/lib/mounts.c b/lib/mounts.c
index 40ebf9cf..a0bf3d52 100644
--- a/lib/mounts.c
+++ b/lib/mounts.c
@@ -1481,6 +1481,53 @@ static void tree_mapent_free(struct tree_node *n)
 	n->right = NULL;
 }
 
+int tree_mapent_add_node(struct mapent_cache *mc,
+			 const char *root, const char *key)
+{
+	unsigned int logopt = mc->ap->logopt;
+	struct tree_node *tree, *n;
+	struct mapent *base;
+	struct mapent *parent;
+	struct mapent *me;
+
+	base = cache_lookup_distinct(mc, root);
+	if (!base) {
+		error(logopt,
+		     "failed to find multi-mount root for key %s", key);
+		return 0;
+	}
+
+	if (MAPENT_ROOT(base) != MAPENT_NODE(base)) {
+		error(logopt,
+		     "failed to find multi-mount root of offset tree",
+		     key);
+		return 0;
+	}
+	tree = MAPENT_ROOT(base);
+
+	me = cache_lookup_distinct(mc, key);
+	if (!me) {
+		error(logopt,
+		     "failed to find key %s of multi-mount", key);
+		return 0;
+	}
+
+	n = tree_add_node(tree, me);
+	if (!n)
+		return 0;
+
+	MAPENT_SET_ROOT(me, tree)
+
+	/* Set the subtree parent */
+	parent = cache_get_offset_parent(mc, key);
+	if (!parent)
+		MAPENT_SET_PARENT(me, tree)
+	else
+		MAPENT_SET_PARENT(me, MAPENT_NODE(parent))
+
+	return 1;
+}
+
 /* From glibc decode_name() */
 /* Since the values in a line are separated by spaces, a name cannot
  * contain a space.  Therefore some programs encode spaces in names