extract the result response before the callback is issued. (ros2#2132)

Signed-off-by: Tomoya Fujita <[email protected]>

Author: fujitatomoya

rclcpp_action/src/client.cpp

@@ -318,14 +318,19 @@ ClientBase::handle_result_response(
   const rmw_request_id_t & response_header,
   std::shared_ptr<void> response)
 {
-  std::lock_guard<std::mutex> guard(pimpl_->result_requests_mutex);
-  const int64_t & sequence_number = response_header.sequence_number;
-  if (pimpl_->pending_result_responses.count(sequence_number) == 0) {
-    RCLCPP_ERROR(pimpl_->logger, "unknown result response, ignoring...");
-    return;
+  std::map<int64_t, ResponseCallback>::node_type pending_result_response;
+  {
+    std::lock_guard<std::mutex> guard(pimpl_->result_requests_mutex);
+    const int64_t & sequence_number = response_header.sequence_number;
+    if (pimpl_->pending_result_responses.count(sequence_number) == 0) {
+      RCLCPP_ERROR(pimpl_->logger, "unknown result response, ignoring...");
+      return;
+    }
+    pending_result_response =
+      pimpl_->pending_result_responses.extract(sequence_number);
   }
-  pimpl_->pending_result_responses[sequence_number](response);
-  pimpl_->pending_result_responses.erase(sequence_number);
+  auto & response_callback = pending_result_response.mapped();
+  response_callback(response);
 }
 
 void