From 29fad09251234d7a35799abe9257c825a2ca36cf Mon Sep 17 00:00:00 2001
From: Dan Connolly <connolly@agoric.com>
Date: Fri, 22 Nov 2024 10:57:00 -0600
Subject: [PATCH] fix!(orchestration): expose subscribeToTransfers() race to
 caller

There was a race in subscribeToTransfers. Rather than fail some cases
with "already registered", return 'RACING' to the loser of the race,
who can then try again.
---
 packages/orchestration/src/exos/packet-tools.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/orchestration/src/exos/packet-tools.js b/packages/orchestration/src/exos/packet-tools.js
index a4ba79c2455..4b051c5be3b 100644
--- a/packages/orchestration/src/exos/packet-tools.js
+++ b/packages/orchestration/src/exos/packet-tools.js
@@ -126,7 +126,7 @@ export const preparePacketTools = (zone, vowTools) => {
       const resolverToPattern = zone.detached().mapStore('resolverToPattern');
       return {
         lca,
-        reg: /** @type {Remote<TargetRegistration> | null} */ (null),
+        reg: /** @type {Remote<TargetRegistration> | 'RACING' | null} */ (null),
         resolverToPattern,
         upcallQueue: /** @type {any[] | null} */ (null),
         pending: 0,
@@ -340,6 +340,7 @@ export const preparePacketTools = (zone, vowTools) => {
           const { tap } = this.facets;
           // XXX racy; fails if subscribeToTransfers is called while this promise is in flight
           // e.g. 'Target "agoric1fakeLCAAddress" already registered'
+          this.state.reg = 'RACING';
           return when(E(lca).monitorTransfers(tap), r => {
             this.state.reg = r;
             return r;