From 0ce89b6d544dd1a5d192014f14a82aec9f05543f Mon Sep 17 00:00:00 2001
From: ThomasV <thomasv@electrum.org>
Date: Mon, 2 Jun 2025 13:22:32 +0200
Subject: [PATCH] PaddedRSTransport: fix busy loop in poll_sbuffer (follow-up
 43ca469774bcbe88df7092ca78f9c6309c8bc42a)

According to the asyncio documentation:

> When a task is cancelled, asyncio.CancelledError will be raised in the task at the next opportunity.

I guess the 'next opportunity' means the next await statement.
Here the issue is that the task was not awaiting ever.

Note: ElectrumX needs a similar patch
---
 electrum/interface.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/electrum/interface.py b/electrum/interface.py
index cf6d52821..4809013f6 100644
--- a/electrum/interface.py
+++ b/electrum/interface.py
@@ -359,7 +359,7 @@ class PaddedRSTransport(RSTransport):
             self._sbuffer_has_data_evt.clear()
 
     async def _poll_sbuffer(self):
-        while True:
+        while not self.is_closing():
             await self._sbuffer_has_data_evt.wait()  # to avoid busy-waiting
             self._maybe_consume_sbuffer()
             # If there is still data in the buffer, sleep until it would time out.