From b043336c867a3731f0bf7285ea5a76b051823e7f Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Fri, 27 Nov 2020 00:11:41 +0100
Subject: [PATCH] Fix monitor-sends with templates

This fixes an issues with missing monitor-sends when creating
a session from a template with monitor-section, or when creating
tracks from a route-template.
---
 libs/ardour/session.cc | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index 759f801362..09bb953959 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -398,6 +398,7 @@ Session::Session (AudioEngine &eng,
 		}
 	}
 
+	/* apply the loaded state_tree */
 	int err = post_engine_init ();
 
 	if (err) {
@@ -422,6 +423,22 @@ Session::Session (AudioEngine &eng,
 		}
 	}
 
+	if (!mix_template.empty()) {
+		/* fixup monitor-sends */
+		if (Config->get_use_monitor_bus ()) {
+			/* Session::config_changed will have set use-monitor-bus to match the template.
+			 * search for want_ms, have_ms
+			 */
+			assert (_monitor_out);
+			/* ..but sends do not exist, since templated track bitslots are unset */
+			setup_route_monitor_sends (true, true);
+		} else {
+			/* remove any monitor-sends that may be in the template */
+			assert (!_monitor_out);
+			setup_route_monitor_sends (false, true);
+		}
+	}
+
 	if (!unnamed) {
 		store_recent_sessions (_name, _path);
 	}
@@ -3057,6 +3074,21 @@ Session::new_route_from_template (uint32_t how_many, PresentationInfo::order_t i
 
 	IO::enable_connecting ();
 
+	if (!ret.empty()) {
+		/* set/unset monitor-send */
+		Glib::Threads::Mutex::Lock lm (_engine.process_lock());
+		for (RouteList::iterator x = ret.begin(); x != ret.end(); ++x) {
+			if ((*x)->can_solo ()) {
+				if (_monitor_out) {
+					(*x)->enable_monitor_send ();
+				} else {
+					/* this may happen with old templates */
+					(*x)->remove_monitor_send ();
+				}
+			}
+		}
+	}
+
 	return ret;
 }