fix: add back atexit handler

rmw_zenoh_cpp/src/detail/rmw_context_impl_s.cpp

@@ -100,9 +100,13 @@ class rmw_context_impl_s::Data final
       RMW_SET_ERROR_MSG("Error setting up zenoh session");
       throw std::runtime_error("Error setting up zenoh session.");
     }
+    atexit(update_is_exiting);
     auto close_session = rcpputils::make_scope_exit(
       [this]() {
-        z_close(z_loan_mut(session_), NULL);
+        // Don't touch Zenoh Session if the ROS process is exiting, it will cause panic.
+        if (!is_exiting) {
+          z_close(z_loan_mut(session_), NULL);
+        }
       });
 
     // Verify if the zenoh router is running if configured.
@@ -265,10 +269,13 @@ class rmw_context_impl_s::Data final
       // to avoid an AB/BA deadlock if shutdown is racing with graph_sub_data_handler().
     }
 
-    // Close the zenoh session
-    if (z_close(z_loan_mut(session_), NULL) != Z_OK) {
-      RMW_SET_ERROR_MSG("Error while closing zenoh session");
-      return RMW_RET_ERROR;
+    // Don't touch Zenoh Session if the ROS process is exiting, it will cause panic.
+    if (!is_exiting) {
+      // Close the zenoh session
+      if (z_close(z_loan_mut(session_), NULL) != Z_OK) {
+        RMW_SET_ERROR_MSG("Error while closing zenoh session");
+        return RMW_RET_ERROR;
+      }
     }
     return RMW_RET_OK;
   }