Not creating rosout publisher instance unless required. (#514)

Signed-off-by: Tomoya.Fujita <Tomoya.Fujita@sony.com>

rcl/include/rcl/logging.h

@@ -71,6 +71,25 @@ RCL_PUBLIC
 RCL_WARN_UNUSED
 rcl_ret_t rcl_logging_fini();
 
+/// See if logging rosout is enabled.
+/**
+ * This function is meant to be used to check if logging rosout is enabled.
+ *
+ * <hr>
+ * Attribute          | Adherence
+ * ------------------ | -------------
+ * Allocates Memory   | No
+ * Thread-Safe        | Yes
+ * Uses Atomics       | No
+ * Lock-Free          | Yes
+ *
+ * \return `TRUE` if logging rosout is enabled, or
+ * \return `FALSE` if logging rosout is disabled.
+ */
+RCL_PUBLIC
+RCL_WARN_UNUSED
+bool rcl_logging_rosout_enabled();
+
 #ifdef __cplusplus
 }
 #endif

rcl/src/rcl/logging.c

@@ -119,6 +119,11 @@ rcl_ret_t rcl_logging_fini()
   return status;
 }
 
+bool rcl_logging_rosout_enabled()
+{
+  return g_rcl_logging_rosout_enabled;
+}
+
 static
 void
 rcl_logging_multiple_output_handler(

rcl/src/rcl/node.c

@@ -26,6 +26,7 @@ extern "C"
 
 #include "rcl/arguments.h"
 #include "rcl/error_handling.h"
+#include "rcl/logging.h"
 #include "rcl/logging_rosout.h"
 #include "rcl/rcl.h"
 #include "rcl/remap.h"
@@ -355,17 +356,19 @@ rcl_node_init(
   }
   // The initialization for the rosout publisher requires the node to be in initialized to a point
   // that it can create new topic publishers
+  if (rcl_logging_rosout_enabled()) {
     ret = rcl_logging_rosout_init_publisher_for_node(node);
     if (ret != RCL_RET_OK) {
       // error message already set
       goto fail;
     }
+  }
   RCUTILS_LOG_DEBUG_NAMED(ROS_PACKAGE_NAME, "Node initialized");
   ret = RCL_RET_OK;
   goto cleanup;
 fail:
   if (node->impl) {
-    if (node->impl->logger_name) {
+    if (rcl_logging_rosout_enabled() && node->impl->logger_name) {
       ret = rcl_logging_rosout_fini_publisher_for_node(node);
       RCUTILS_LOG_ERROR_EXPRESSION_NAMED((ret != RCL_RET_OK && ret != RCL_RET_NOT_INIT),
         ROS_PACKAGE_NAME, "Failed to fini publisher for node: %i", ret);
@@ -431,11 +434,14 @@ rcl_node_fini(rcl_node_t * node)
   }
   rcl_allocator_t allocator = node->impl->options.allocator;
   rcl_ret_t result = RCL_RET_OK;
-  rcl_ret_t rcl_ret = rcl_logging_rosout_fini_publisher_for_node(node);
+  rcl_ret_t rcl_ret = RCL_RET_OK;
+  if (rcl_logging_rosout_enabled()) {
+    rcl_ret = rcl_logging_rosout_fini_publisher_for_node(node);
     if (rcl_ret != RCL_RET_OK && rcl_ret != RCL_RET_NOT_INIT) {
       RCL_SET_ERROR_MSG("Unable to fini publisher for node.");
       result = RCL_RET_ERROR;
     }
+  }
   rmw_ret_t rmw_ret = rmw_destroy_node(node->impl->rmw_node_handle);
   if (rmw_ret != RMW_RET_OK) {
     RCL_SET_ERROR_MSG(rmw_get_error_string().str);