Fix spin_until_future_complete: check spinning value (#1023)

Signed-off-by: Donghee Ye <donghee.ye@samsung.com>

Make Executor::spin_once_impl private before backporting, to avoid API compatibility issues

Signed-off-by: Ivan Santiago Paunovic <ivanpauno@ekumenlabs.com>

rclcpp/include/rclcpp/executor.hpp

@@ -37,6 +37,7 @@
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
 #include "rclcpp/utilities.hpp"
 #include "rclcpp/visibility_control.hpp"
+#include "rclcpp/scope_exit.hpp"
 
 namespace rclcpp
 {
@@ -212,9 +213,14 @@ class Executor
     }
     std::chrono::nanoseconds timeout_left = timeout_ns;
 
-    while (rclcpp::ok(this->context_)) {
+    if (spinning.exchange(true)) {
+      throw std::runtime_error("spin_until_future_complete() called while already spinning");
+    }
+    RCLCPP_SCOPE_EXIT(this->spinning.store(false); );
+    while (rclcpp::ok(this->context_) && spinning.load()) {
       // Do one item of work.
-      spin_once(timeout_left);
+      spin_once_impl(timeout_left);
+
       // Check if the future is set, return SUCCESS if it is.
       status = future.wait_for(std::chrono::seconds(0));
       if (status == std::future_status::ready) {
@@ -338,6 +344,11 @@ class Executor
 
   std::list<rclcpp::node_interfaces::NodeBaseInterface::WeakPtr> weak_nodes_;
   std::list<const rcl_guard_condition_t *> guard_conditions_;
+
+private:
+  RCLCPP_PUBLIC
+  void
+  spin_once_impl(std::chrono::nanoseconds timeout);
 };
 
 namespace executor

rclcpp/src/rclcpp/executor.cpp

@@ -244,17 +244,23 @@ Executor::spin_some(std::chrono::nanoseconds max_duration)
   }
 }
 
+void
+Executor::spin_once_impl(std::chrono::nanoseconds timeout)
+{
+  AnyExecutable any_exec;
+  if (get_next_executable(any_exec, timeout)) {
+    execute_any_executable(any_exec);
+  }
+}
+
 void
 Executor::spin_once(std::chrono::nanoseconds timeout)
 {
   if (spinning.exchange(true)) {
     throw std::runtime_error("spin_once() called while already spinning");
   }
   RCLCPP_SCOPE_EXIT(this->spinning.store(false); );
-  AnyExecutable any_exec;
-  if (get_next_executable(any_exec, timeout)) {
-    execute_any_executable(any_exec);
-  }
+  spin_once_impl(timeout);
 }
 
 void