From 08369358888182d75b1bd591cc19e9fe028ee849 Mon Sep 17 00:00:00 2001
From: ImBenji <bw23584@essex.ac.uk>
Date: Thu, 11 Dec 2025 17:40:35 +0000
Subject: [PATCH] Fixed windows deadlocks, performance is shit tho

---
 cpp/src/Private/sweepstore/concurrency.cpp  | 28 +++++++++++++++++----
 cpp/src/Public/sweepstore/utils/file_lock.h |  3 +++
 2 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/cpp/src/Private/sweepstore/concurrency.cpp b/cpp/src/Private/sweepstore/concurrency.cpp
index 64807d4..05bef90 100644
--- a/cpp/src/Private/sweepstore/concurrency.cpp
+++ b/cpp/src/Private/sweepstore/concurrency.cpp
@@ -107,13 +107,13 @@ void SweepstoreConcurrency::spawnTicket(SweepstoreFileHandle* _file,
 
                 SweepstoreWorkerTicketSnapshot snapshot = ticket.snapshot();
 
-                int identifier = snapshot.identifier;
+                uint32_t identifier = snapshot.identifier;
 
                 bool identifier_unassigned = identifier == 0;
                 bool stale_heartbeat = millisecondsSinceEpoch32() - snapshot.workerHeartbeat > STALE_HEARTBEAT_THRESHOLD_MS;
                 bool is_free = snapshot.state == SweepstoreTicketState::FREE;
 
-                if (identifier_unassigned && stale_heartbeat && is_free) {
+                if ((identifier_unassigned && is_free) || stale_heartbeat) {
                     SWEEPSTORE_TIME_SCOPE("Claim Ticket");
                     snapshot.identifier = newIdentifier;
                     snapshot.workerHeartbeat = millisecondsSinceEpoch32();
@@ -218,7 +218,7 @@ void SweepstoreConcurrency::initialiseMaster(std::string filePath) {
     SWEEPSTORE_TIME_FUNCTION();
 
     auto log = [&](const std::string &message) {
-        debugPrint("\033[38;5;33m[Concurrency Master]:\033[0m " + message);
+        debugPrint(("\033[38;5;33m[Concurrency Master]:\033[0m " + message).c_str());
     };
 
     SweepstoreFileHandle file(filePath, std::ios::binary | std::ios::in | std::ios::out);
@@ -252,9 +252,27 @@ void SweepstoreConcurrency::initialiseMaster(std::string filePath) {
                 ticket.write(cleanSnapshot);
                 log("Reset ticket " + std::to_string(i) + ".");
             }
+        }
 
-            // Handle stale tickets
-            uint32_t currentTime = millisecondsSinceEpoch32();
+        continue;
+
+        // Cleanup any stale tickets
+        uint32_t currentTime = millisecondsSinceEpoch32();
+        for (uint32_t i = 0; i < concurrentWorkers; i++) {
+            SweepstoreWorkerTicket ticket(i, file);
+            SweepstoreWorkerTicketSnapshot snapshot = ticket.snapshot();
+
+            if (snapshot.state != SweepstoreTicketState::FREE) {
+                continue;
+            }
+
+            bool stale_heartbeat = currentTime - snapshot.workerHeartbeat > STALE_HEARTBEAT_THRESHOLD_MS;
+
+            if (stale_heartbeat) {
+                SweepstoreWorkerTicketSnapshot cleanSnapshot = SweepstoreWorkerTicketSnapshot();
+                ticket.write(cleanSnapshot);
+                log("Stale heartbeat " + std::to_string(i) + ".");
+            }
         }
 
         preciseSleep(std::chrono::milliseconds(1));
diff --git a/cpp/src/Public/sweepstore/utils/file_lock.h b/cpp/src/Public/sweepstore/utils/file_lock.h
index 12b7f31..4a60980 100644
--- a/cpp/src/Public/sweepstore/utils/file_lock.h
+++ b/cpp/src/Public/sweepstore/utils/file_lock.h
@@ -84,6 +84,9 @@ private:
             if (it->second == Mode::Shared && mode == Mode::Exclusive) {
                 releaseInternal();  // Release the old shared lock
                 activeLocks.erase(it);
+                // Small delay to allow OS to process the unlock before re-locking
+                // This prevents deadlock when multiple threads upgrade simultaneously
+                Sleep(1);
             } else {
                 // Already hold compatible or same lock
                 locked = true;