From dedcbd8c1e65f86e986831807d6b4ef8cfbfcf00 Mon Sep 17 00:00:00 2001
From: Alexander Krotov <krotov@iitp.ru>
Date: Sun, 22 Aug 2021 18:38:15 +0300
Subject: [PATCH] Implement BlockAckManager::DoDispose ()

Nullify all Ptr's there to remove possible circular references.

Do not set m_queue Ptr in the destructor, it is destroyed anyway.
---
 src/wifi/model/block-ack-manager.cc | 12 ++++++++++--
 src/wifi/model/block-ack-manager.h  |  3 +++
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/wifi/model/block-ack-manager.cc b/src/wifi/model/block-ack-manager.cc
index 233c25ccb..b42a71a95 100644
--- a/src/wifi/model/block-ack-manager.cc
+++ b/src/wifi/model/block-ack-manager.cc
@@ -72,9 +72,17 @@ BlockAckManager::BlockAckManager ()
 BlockAckManager::~BlockAckManager ()
 {
   NS_LOG_FUNCTION (this);
-  m_queue = 0;
+}
+
+void
+BlockAckManager::DoDispose ()
+{
+  NS_LOG_FUNCTION (this);
   m_agreements.clear ();
-  m_retryPackets = 0;
+  m_retryPackets = nullptr;
+  m_bars.clear ();
+  m_queue = nullptr;
+  m_stationManager = nullptr;
 }
 
 bool
diff --git a/src/wifi/model/block-ack-manager.h b/src/wifi/model/block-ack-manager.h
index cafc5ddc5..78ee71d62 100644
--- a/src/wifi/model/block-ack-manager.h
+++ b/src/wifi/model/block-ack-manager.h
@@ -431,6 +431,9 @@ public:
    */
   void ScheduleBar (Ptr<const WifiMacQueueItem> bar, bool skipIfNoDataQueued = false);
 
+protected:
+  void DoDispose () override;
+
 private:
   /**
    * Inactivity timeout function