From f1f396e338bd9130da3e52d60f3a79ca469a005d Mon Sep 17 00:00:00 2001
From: Daniel Agar <daniel@agar.ca>
Date: Fri, 26 Feb 2021 10:05:43 -0500
Subject: [PATCH] uORB: PublicationMulti get_instance() advertise if not
 already advertised

 - fixes UAVCANv0 sensor bridge uORB usage, but also a reason thing to do in general
---
 platforms/common/uORB/PublicationMulti.hpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/platforms/common/uORB/PublicationMulti.hpp b/platforms/common/uORB/PublicationMulti.hpp
index cecb76324f..7a91bc907e 100644
--- a/platforms/common/uORB/PublicationMulti.hpp
+++ b/platforms/common/uORB/PublicationMulti.hpp
@@ -92,9 +92,10 @@ public:
 		return (orb_publish(get_topic(), _handle, &data) == PX4_OK);
 	}
 
-	int get_instance() const
+	int get_instance()
 	{
-		if (_handle) {
+		// advertise if not already advertised
+		if (advertise()) {
 			return static_cast<uORB::DeviceNode *>(_handle)->get_instance();
 		}