From e6ccad87b42c80750c3251eb791796e199d49232 Mon Sep 17 00:00:00 2001
From: ImBenji <benjamin.watt@imbenji.net>
Date: Sun, 23 Nov 2025 21:02:40 +0000
Subject: [PATCH] Refactor logging and ticket ownership verification in
 concurrency handling for improved clarity and reliability

---
 dart/lib/concurrency.dart | 22 +++++++++++++++++-----
 dart/lib/header.dart      |  4 ++--
 2 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/dart/lib/concurrency.dart b/dart/lib/concurrency.dart
index c258fab..1b6939b 100644
--- a/dart/lib/concurrency.dart
+++ b/dart/lib/concurrency.dart
@@ -36,7 +36,7 @@ void spawnTicket(RandomAccessFile file, {
   void log(String message) {
 
     String prefix = debugLabel != null ? "\x1B[38;5;208m[Ticket Spawner - $debugLabel]:\x1B[0m " : "\x1B[38;5;208m[Ticket Spawner]:\x1B[0m ";
-    // print("$prefix$message");
+    print("$prefix$message");
 
   }
 
@@ -90,7 +90,7 @@ void spawnTicket(RandomAccessFile file, {
             ticketState: SweepstoreTicketState.WAITING,
           );
           ticketIndex = i;
-          log("Acquired ticket $ticketIndex with identifier $newIdentifier.");
+          // log("Acquired ticket $ticketIndex with identifier $newIdentifier.");
           break;
 
         }
@@ -104,7 +104,7 @@ void spawnTicket(RandomAccessFile file, {
         SweepstoreWorkerTicketSnapshot verifySnapshot = concurrencyHeader[ticketIndex].snapshot();
 
         if (verifySnapshot.identifier != newIdentifier) {
-          log("Lost ticket $ticketIndex, retrying...");
+          // log("Lost ticket $ticketIndex, retrying...");
           ticketIndex = null;
         } else {
           return concurrencyHeader[ticketIndex];
@@ -139,8 +139,20 @@ void spawnTicket(RandomAccessFile file, {
 
     // Check we still own the ticket
     if (snapshot.identifier != myIdentifier) {
-      String exceptionMessage = "CRITICAL: Lost ownership of ticket ${myTicket.ticketIndex}, was expecting identifier $myIdentifier but found ${snapshot.identifier}.";
-      throw Exception(exceptionMessage);
+      
+      preciseSleep(Duration(milliseconds: 10));
+
+      // Re-verify we lost the ticket
+      SweepstoreWorkerTicketSnapshot recheckSnapshot = myTicket.snapshot();
+      if (recheckSnapshot.identifier != myIdentifier) {
+        String exceptionMessage = "CRITICAL: Lost ownership of ticket ${myTicket.ticketIndex}, was expecting identifier $myIdentifier but found ${snapshot.identifier}.";
+        // throw Exception(exceptionMessage);
+        log(exceptionMessage);
+        return spawnTicket(file, operation: operation, keyHash: keyHash, writeSize: writeSize, onApproved: onApproved);
+      }
+
+      // Nvm, false alarm
+      log("False alarm, still own ticket ${myTicket.ticketIndex}.");
     }
 
     if (snapshot.ticketState == SweepstoreTicketState.APPROVED) {
diff --git a/dart/lib/header.dart b/dart/lib/header.dart
index 85b8e46..ce27781 100644
--- a/dart/lib/header.dart
+++ b/dart/lib/header.dart
@@ -362,12 +362,12 @@ class SweepstoreWorkerTicket {
 
   SweepstoreWorkerTicketSnapshot snapshot() {
 
-    // _concurrencyHeader._header._file.lockSync(FileLock.blockingShared, _baseOffset, _baseOffset + ticketSize);
+    _concurrencyHeader._header._file.lockSync(FileLock.blockingShared, _baseOffset, _baseOffset + ticketSize);
 
     _concurrencyHeader._header._file.setPositionSync(_baseOffset);
     List<int> existingBuffer = _concurrencyHeader._header._file.readSync(ticketSize);
     RandomAccessMemory buffer = RandomAccessMemory(existingBuffer);
-    // _concurrencyHeader._header._file.unlockSync(_baseOffset, _baseOffset + ticketSize);
+    _concurrencyHeader._header._file.unlockSync(_baseOffset, _baseOffset + ticketSize);
 
     buffer.setPositionSync(0);
     int identifier = buffer.readIntSync(4);