aligh with rcl that a rosout publisher of a node might not exist (#2357)

* aligh with rcl

* keep same behavior with rclpy

1. to not throw exception durning rcl_logging_rosout_remove_sublogger
2. reset error message for RCL_RET_NOT_FOUND

* test for a node with rosout disabled

Signed-off-by: Chen Lihui <lihui.chen@sony.com>

rclcpp/src/rclcpp/logger.cpp

@@ -17,6 +17,7 @@
 #include <utility>
 
 #include "rcl_logging_interface/rcl_logging_interface.h"
+#include "rcl/error_handling.h"
 #include "rcl/logging_rosout.h"
 
 #include "rclcpp/exceptions.hpp"
@@ -80,10 +81,12 @@ Logger::get_child(const std::string & suffix)
   {
     std::lock_guard<std::recursive_mutex> guard(*logging_mutex);
     rcl_ret = rcl_logging_rosout_add_sublogger((*name_).c_str(), suffix.c_str());
-    if (RCL_RET_OK != rcl_ret) {
+    if (RCL_RET_NOT_FOUND == rcl_ret) {
+      rcl_reset_error();
+    } else if (RCL_RET_OK != rcl_ret) {
       exceptions::throw_from_rcl_error(
         rcl_ret, "failed to call rcl_logging_rosout_add_sublogger",
-        rcutils_get_error_state(), rcutils_reset_error);
+        rcl_get_error_state(), rcl_reset_error);
     }
   }
 
@@ -98,9 +101,7 @@ Logger::get_child(const std::string & suffix)
           logger_sublogger_pairname_ptr->second.c_str());
         delete logger_sublogger_pairname_ptr;
         if (RCL_RET_OK != rcl_ret) {
-          exceptions::throw_from_rcl_error(
-            rcl_ret, "failed to call rcl_logging_rosout_remove_sublogger",
-            rcutils_get_error_state(), rcutils_reset_error);
+          rcl_reset_error();
         }
       });
   }

rclcpp/test/rclcpp/test_rosout_subscription.cpp

@@ -178,3 +178,13 @@ TEST_F(TestRosoutSubscription, test_rosoutsubscription_getchild_hierarchy) {
   EXPECT_TRUE(future.get());
   received_msg_promise = {};
 }
+
+TEST_F(TestRosoutSubscription, test_rosoutsubscription_node_rosout_disabled) {
+  rclcpp::NodeOptions options = rclcpp::NodeOptions().enable_rosout(false);
+  auto node = std::make_shared<rclcpp::Node>("my_node", options);
+  auto log_func = [&node] {
+      auto logger = node->get_logger().get_child("child");
+      RCLCPP_INFO(logger, "test");
+    };
+  ASSERT_NO_THROW(log_func());
+}