From f0188e998009d87511418d8bb1c4dc779e2ea7fa Mon Sep 17 00:00:00 2001
From: Timo Sirainen <timo.sirainen@open-xchange.com>
Date: Thu, 25 Sep 2025 11:36:46 +0300
Subject: [PATCH] lib-storage: Fix subscription listing showing parent
 namespace prefix

If e.g. shared/user/box was subscribed, LSUB "" % didn't list shared
namespace prefix.
---
 src/lib-storage/list/mailbox-list-iter.c | 31 ++++++++++++++++++++++++
 src/lib-storage/mailbox-tree.c           |  5 ++++
 src/lib-storage/mailbox-tree.h           |  1 +
 3 files changed, 37 insertions(+)

diff --git a/src/lib-storage/list/mailbox-list-iter.c b/src/lib-storage/list/mailbox-list-iter.c
index a65c1be54a..5385902d93 100644
--- a/src/lib-storage/list/mailbox-list-iter.c
+++ b/src/lib-storage/list/mailbox-list-iter.c
@@ -486,6 +486,29 @@ mailbox_ns_prefix_check_selection_criteria(struct ns_list_iterate_context *ctx)
 	return TRUE;
 }
 
+static int ns_has_child_subscriptions(struct ns_list_iterate_context *ctx,
+				      struct mail_namespace *parent_ns)
+{
+	struct mail_namespace *ns;
+
+	for (ns = ctx->namespaces; ns != NULL; ns = ns->next) {
+		if (ns->prefix_len > parent_ns->prefix_len &&
+		    strncmp(ns->prefix, parent_ns->prefix,
+			    parent_ns->prefix_len) == 0) {
+			if (mailbox_list_iter_subscriptions_refresh(ns->list) < 0)
+				return -1;
+
+			if (mailbox_tree_get_root(ns->list->subscriptions) != NULL)
+				return 1;
+
+			int ret = ns_has_child_subscriptions(ctx, ns);
+			if (ret != 0)
+				return ret;
+		}
+	}
+	return 0;
+}
+
 static bool
 mailbox_list_ns_prefix_return(struct ns_list_iterate_context *ctx,
 			      struct mail_namespace *ns, bool has_children)
@@ -570,6 +593,14 @@ mailbox_list_ns_prefix_return(struct ns_list_iterate_context *ctx,
 			   have a child is if one of them is subscribed */
 			subs_flags = MAILBOX_CHILD_SUBSCRIBED;
 		}
+		if (subs_flags == 0) {
+			if ((ret = ns_has_child_subscriptions(ctx, ns)) < 0) {
+				mailbox_list_ns_iter_failed(ctx);
+				return FALSE;
+			}
+			if (ret > 0)
+				subs_flags = MAILBOX_CHILD_SUBSCRIBED;
+		}
 		if (subs_flags != 0 &&
 		    mailbox_list_want_subscription(ns, ctx->ns_info.flags |
 						   subs_flags))
diff --git a/src/lib-storage/mailbox-tree.c b/src/lib-storage/mailbox-tree.c
index 94945aeae3..c2ea74ca3e 100644
--- a/src/lib-storage/mailbox-tree.c
+++ b/src/lib-storage/mailbox-tree.c
@@ -80,6 +80,11 @@ pool_t mailbox_tree_get_pool(struct mailbox_tree_context *tree)
 	return tree->pool;
 }
 
+struct mailbox_node *mailbox_tree_get_root(struct mailbox_tree_context *tree)
+{
+	return tree->nodes;
+}
+
 static struct mailbox_node * ATTR_NULL(2)
 mailbox_tree_traverse(struct mailbox_tree_context *tree, const char *path,
 		      bool create, bool *created_r)
diff --git a/src/lib-storage/mailbox-tree.h b/src/lib-storage/mailbox-tree.h
index aeb45c4849..b8b014a8f6 100644
--- a/src/lib-storage/mailbox-tree.h
+++ b/src/lib-storage/mailbox-tree.h
@@ -23,6 +23,7 @@ void mailbox_tree_set_separator(struct mailbox_tree_context *tree,
 void mailbox_tree_set_parents_nonexistent(struct mailbox_tree_context *tree);
 void mailbox_tree_clear(struct mailbox_tree_context *tree);
 pool_t mailbox_tree_get_pool(struct mailbox_tree_context *tree);
+struct mailbox_node *mailbox_tree_get_root(struct mailbox_tree_context *tree);
 
 struct mailbox_node *
 mailbox_tree_get(struct mailbox_tree_context *tree, const char *path,
-- 
2.47.3