From f2e9701b9cbf87989fcde600a9f506b31c3c6283 Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Wed, 4 Feb 2026 03:11:41 +0000
Subject: [PATCH] fix(socket): move PreKey sync reschedule check inside finally
 block
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Minimizes race window between isRunning=false and reschedule check by
moving the setTimeout reschedule logic inside the finally block.

Changes:
- Move reschedule check (if !closed && !cleanedUp && ws.isOpen) from
  after finally block to inside finally block
- Reduces race window where end() could be called between finally and check

Timeline before fix:
T0: syncLoop finally executes → isRunning = false
T1: end() called → closed = true
T2: syncLoop checks if (!closed) ← sees false
T3: setTimeout scheduled ← orphaned timer
T4: cleanupPreKeyAutoSync() clears it

Timeline after fix:
T0: syncLoop finally executes → isRunning = false
T1: Immediately checks flags INSIDE finally (atomic)
T2: Window too small for race condition

Risk: LOW (cleanup function already handles orphaned timers)
Impact: Cleaner code, minimizes theoretical race window

https://claude.ai/code/session_VMxqX
---
 src/Socket/socket.ts | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/Socket/socket.ts b/src/Socket/socket.ts
index 7467e8f0..64bea367 100644
--- a/src/Socket/socket.ts
+++ b/src/Socket/socket.ts
@@ -766,12 +766,12 @@ export const makeSocket = (config: SocketConfig) => {
 				logger.error({ error }, '🔑 PreKey auto-sync failed')
 			} finally {
 				isRunning = false
-			}
 
-			// PROTECTION 3: Prevent timer accumulation and post-cleanup rescheduling
-			// Check cleanedUp flag atomically to prevent race condition
-			if (!closed && !cleanedUp && ws.isOpen) {
-				syncTimer = setTimeout(syncLoop, SYNC_INTERVAL)
+				// PROTECTION 3: Prevent timer accumulation and post-cleanup rescheduling
+				// Check cleanedUp flag atomically INSIDE finally to minimize race window
+				if (!closed && !cleanedUp && ws.isOpen) {
+					syncTimer = setTimeout(syncLoop, SYNC_INTERVAL)
+				}
 			}
 		}