From a9015334eedfde063e070cc7bb63f21c5ac162b0 Mon Sep 17 00:00:00 2001
From: Dmitry Kargin <dmitry.n.kargin@gmail.com>
Date: Sat, 30 Nov 2024 18:22:36 +0300
Subject: [PATCH] More checks in Connection class

---
 include/miniros/internal/observer.h | 10 ++++++++++
 src/transport/connection.cpp        |  5 +++--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/include/miniros/internal/observer.h b/include/miniros/internal/observer.h
index ca809bd..efe11da 100644
--- a/include/miniros/internal/observer.h
+++ b/include/miniros/internal/observer.h
@@ -1,6 +1,7 @@
 #ifndef MINIROS_OBSERVER_H
 #define MINIROS_OBSERVER_H
 
+#include <cassert>
 #include <type_traits> // for std::is_base_of
 
 namespace miniros {
@@ -98,6 +99,15 @@ class Iterator {
         return *m_obj;
     }
 
+    operator bool () const {
+        return m_obj != nullptr;
+    }
+
+    ConnectionImpl* operator -> () {
+        assert(m_obj);
+        return m_obj;
+    }
+
 protected:
     ConnectionImpl* m_obj;
 };
diff --git a/src/transport/connection.cpp b/src/transport/connection.cpp
index 08d5c9f..f9c2421 100644
--- a/src/transport/connection.cpp
+++ b/src/transport/connection.cpp
@@ -357,8 +357,9 @@ void Connection::drop(DropReason reason)
         std::scoped_lock<DropWatchers> lock(drop_watchers_);
         for (auto it = drop_watchers_.begin(); it != drop_watchers_.end(); it++)
         {
-            DropWatcher& watcher = *it;
-            watcher.onConnectionDropped(shared_from_this(), reason);
+            if (!it)
+              continue;
+            it->onConnectionDropped(shared_from_this(), reason);
         }
     }
     transport_->close();