From a38fe792c95efc26c1c5c2dc80d749bf9d28f9a8 Mon Sep 17 00:00:00 2001
From: Michael Heine <michael.heine@knapp.com>
Date: Thu, 16 Jan 2025 16:05:49 +0000
Subject: [PATCH] Fixed deadlock in destructor in TransformListener

---
 tf2_ros/include/tf2_ros/transform_listener.h | 10 +++++++++-
 tf2_ros/src/transform_listener.cpp           |  1 +
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/tf2_ros/include/tf2_ros/transform_listener.h b/tf2_ros/include/tf2_ros/transform_listener.h
index 4f5e5eaf5..e9ba1a7f2 100644
--- a/tf2_ros/include/tf2_ros/transform_listener.h
+++ b/tf2_ros/include/tf2_ros/transform_listener.h
@@ -32,6 +32,7 @@
 #ifndef TF2_ROS__TRANSFORM_LISTENER_H_
 #define TF2_ROS__TRANSFORM_LISTENER_H_
 
+#include <atomic>
 #include <functional>
 #include <memory>
 #include <thread>
@@ -211,7 +212,13 @@ class TransformListener
       // Create executor with dedicated thread to spin.
       executor_ = std::make_shared<rclcpp::executors::SingleThreadedExecutor>();
       executor_->add_callback_group(callback_group_, node_base_interface_);
-      dedicated_listener_thread_ = std::make_unique<std::thread>([&]() {executor_->spin();});
+      running_.store(true);
+      dedicated_listener_thread_ = std::make_unique<std::thread>(
+        [&]() {
+          while (running_.load()) {
+            executor_->spin_once();
+          }
+        });
       // Tell the buffer we have a dedicated thread to enable timeouts
       buffer_.setUsingDedicatedThread(true);
     } else {
@@ -229,6 +236,7 @@ class TransformListener
     }
   }
 
+  std::atomic<bool> running_;
   bool spin_thread_{false};
   std::unique_ptr<std::thread> dedicated_listener_thread_ {nullptr};
   rclcpp::Executor::SharedPtr executor_ {nullptr};
diff --git a/tf2_ros/src/transform_listener.cpp b/tf2_ros/src/transform_listener.cpp
index 55e946496..b83d8c5cb 100644
--- a/tf2_ros/src/transform_listener.cpp
+++ b/tf2_ros/src/transform_listener.cpp
@@ -71,6 +71,7 @@ TransformListener::TransformListener(tf2::BufferCore & buffer, bool spin_thread,
 TransformListener::~TransformListener()
 {
   if (spin_thread_) {
+    running_.store(false);
     executor_->cancel();
     dedicated_listener_thread_->join();
   }