From aa89eb35759cea74daaff5ca9c42cedfca314127 Mon Sep 17 00:00:00 2001
From: "Roger A. Light" <roger@atchoo.org>
Date: Mon, 3 Feb 2025 09:30:57 +0000
Subject: [PATCH] Minor sub tree refactor

---
 src/database.c                        | 12 +-----------
 src/mosquitto_broker_internal.h       |  2 +-
 src/subs.c                            | 21 +++++++++++++++++++--
 test/unit/broker/persist_read_stubs.c |  4 ++++
 4 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/src/database.c b/src/database.c
index ba7c0e85..05c3939a 100644
--- a/src/database.c
+++ b/src/database.c
@@ -180,8 +180,6 @@ static void db__msg_remove_from_queued_stats(struct mosquitto_msg_data *msg_data
 
 int db__open(struct mosquitto__config *config)
 {
-	struct mosquitto__subhier *subhier;
-
 	if(!config) return MOSQ_ERR_INVAL;
 
 	db.contexts_by_id = NULL;
@@ -198,15 +196,7 @@ int db__open(struct mosquitto__config *config)
 	db.normal_subs = NULL;
 	db.shared_subs = NULL;
 
-	subhier = sub__add_hier_entry(NULL, &db.shared_subs, "", 0);
-	if(!subhier) return MOSQ_ERR_NOMEM;
-
-	subhier = sub__add_hier_entry(NULL, &db.normal_subs, "", 0);
-	if(!subhier) return MOSQ_ERR_NOMEM;
-
-	subhier = sub__add_hier_entry(NULL, &db.normal_subs, "$SYS", (uint16_t)strlen("$SYS"));
-	if(!subhier) return MOSQ_ERR_NOMEM;
-
+	sub__init();
 	retain__init();
 
 	db.config->security_options.unpwd = NULL;
diff --git a/src/mosquitto_broker_internal.h b/src/mosquitto_broker_internal.h
index d87ae0a8..bdcbe72b 100644
--- a/src/mosquitto_broker_internal.h
+++ b/src/mosquitto_broker_internal.h
@@ -743,8 +743,8 @@ void db__check_acl_of_all_messages(struct mosquitto *context);
 /* ============================================================
  * Subscription functions
  * ============================================================ */
+int sub__init(void);
 int sub__add(struct mosquitto *context, const struct mosquitto_subscription *sub);
-struct mosquitto__subhier *sub__add_hier_entry(struct mosquitto__subhier *parent, struct mosquitto__subhier **sibling, const char *topic, uint16_t len);
 int sub__remove(struct mosquitto *context, const char *sub, uint8_t *reason);
 void sub__tree_print(struct mosquitto__subhier *root, int level);
 int sub__clean_session(struct mosquitto *context);
diff --git a/src/subs.c b/src/subs.c
index 6045f808..31f384e9 100644
--- a/src/subs.c
+++ b/src/subs.c
@@ -59,6 +59,8 @@ Contributors:
 
 #include "utlist.h"
 
+static struct mosquitto__subhier *sub__add_hier_entry(struct mosquitto__subhier *parent, struct mosquitto__subhier **sibling, const char *topic, uint16_t len);
+
 static int subs__send(struct mosquitto__subleaf *leaf, const char *topic, uint8_t qos, int retain, struct mosquitto__base_msg *stored)
 {
 	bool client_retain;
@@ -523,7 +525,7 @@ static int sub__search(struct mosquitto__subhier *subhier, char **split_topics,
 }
 
 
-struct mosquitto__subhier *sub__add_hier_entry(struct mosquitto__subhier *parent, struct mosquitto__subhier **sibling, const char *topic, uint16_t len)
+static struct mosquitto__subhier *sub__add_hier_entry(struct mosquitto__subhier *parent, struct mosquitto__subhier **sibling, const char *topic, uint16_t len)
 {
 	struct mosquitto__subhier *child;
 
@@ -536,7 +538,9 @@ struct mosquitto__subhier *sub__add_hier_entry(struct mosquitto__subhier *parent
 	}
 	child->parent = parent;
 	child->topic_len = len;
-	strncpy(child->topic, topic, len);
+	if(len > 0){
+		strncpy(child->topic, topic, len);
+	}
 
 	HASH_ADD(hh, *sibling, topic, child->topic_len, child);
 
@@ -794,3 +798,16 @@ void sub__tree_print(struct mosquitto__subhier *root, int level)
 		sub__tree_print(branch->children, level+1);
 	}
 }
+
+int sub__init(void)
+{
+	if(sub__add_hier_entry(NULL, &db.shared_subs, "", 0) == NULL
+			|| sub__add_hier_entry(NULL, &db.normal_subs, "", 0) == NULL
+			|| sub__add_hier_entry(NULL, &db.normal_subs, "$SYS", (uint16_t)strlen("$SYS")) == NULL
+			){
+
+		return MOSQ_ERR_NOMEM;
+	}else{
+		return MOSQ_ERR_SUCCESS;
+	}
+}
diff --git a/test/unit/broker/persist_read_stubs.c b/test/unit/broker/persist_read_stubs.c
index 52b338d1..b2708efc 100644
--- a/test/unit/broker/persist_read_stubs.c
+++ b/test/unit/broker/persist_read_stubs.c
@@ -251,3 +251,7 @@ int send__pubrel(struct mosquitto *mosq, uint16_t mid, const mosquitto_property
 	return MOSQ_ERR_SUCCESS;
 }
 
+int sub__init(void)
+{
+	return MOSQ_ERR_SUCCESS;
+}