From 662aa83219871a4388edc918c6bd968577cec7d5 Mon Sep 17 00:00:00 2001
From: Moin Shaikh <78309271+Moin2002-tech@users.noreply.github.com>
Date: Thu, 8 Jan 2026 15:02:07 +0530
Subject: [PATCH 1/2] Fix segmentation fault with mutex locking
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So, the reason the app is crashing is actually a classic race condition. The best way to handle this is to put the lock inside the main importFromFile_Json function itself, rather than just in the async one. Even though asyncImportFromFile_Json is what kicks off the new thread, it’s really just a wrapper. If we only put the lock there, we’d still be in trouble if we ever called the regular import directly while an async task was already running in the background.

By adding std::lock_guard<std::mutex> lock(mutex_); right at the start of importFromFile_Json, we make sure that no matter how it gets called, it always waits its turn before touching shared data like the items map or the undoHistory.

Looking at the logs, it seems like the crash happened because one thread was trying to clear the items while another was right in the middle of adding "beta" or "alpha." They ended up stepping on each other's toes in memory, which is a total recipe for a segfault. If we place the lock right after the JSON file is read but before we do items.clear(), we're golden. This way, we don't block other threads while the computer is doing the slow work of reading from the disk, but we're fully protected the second we start changing the actual manager state. It’s the same logic used in addItem, so it keeps everything consistent and stops those random crashes during the threaded tests!
---
 src/t_manager/ItemManager.tpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/t_manager/ItemManager.tpp b/src/t_manager/ItemManager.tpp
index 7ba3331..70c91fa 100644
--- a/src/t_manager/ItemManager.tpp
+++ b/src/t_manager/ItemManager.tpp
@@ -475,7 +475,7 @@ void ItemManager::importFromFile_Json(const std::string& filename) {
     if (!in) {
         LOG_CONTEXT(LogLevel::ERR, "Cannot open file for reading: " + filename, ErrorCode::FILE_LOAD_FAILED);
     }
-
+    std::lock_guard<std::mutex> lock(mutex_) // Segmentation Fix
     json parsedJson;
     in >> parsedJson;
 
@@ -775,7 +775,7 @@ bool ItemManager::importFromFile_Binary(const std::string& filename) {
         LOG_CONTEXT(LogLevel::ERR, "Cannot open binary file '" + filename + "' for reading.", false);
         return false;
     }
-
+   std::lock_guard<std::mutex> lock(mutex_)
     undoHistory.push_back(cloneCurrentState());
     redoQueue = {};
     items.clear();

From 9557d360e240cb8691a6fad95281e058285c6977 Mon Sep 17 00:00:00 2001
From: Moin Shaikh <78309271+Moin2002-tech@users.noreply.github.com>
Date: Thu, 8 Jan 2026 15:11:49 +0530
Subject: [PATCH 2/2] Fix missing semicolon in lock_guard usage

Fixed missing semicolon in lock_guard initialization.
---
 src/t_manager/ItemManager.tpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/t_manager/ItemManager.tpp b/src/t_manager/ItemManager.tpp
index 70c91fa..353cc26 100644
--- a/src/t_manager/ItemManager.tpp
+++ b/src/t_manager/ItemManager.tpp
@@ -475,7 +475,7 @@ void ItemManager::importFromFile_Json(const std::string& filename) {
     if (!in) {
         LOG_CONTEXT(LogLevel::ERR, "Cannot open file for reading: " + filename, ErrorCode::FILE_LOAD_FAILED);
     }
-    std::lock_guard<std::mutex> lock(mutex_) // Segmentation Fix
+    std::lock_guard<std::mutex> lock(mutex_); // Segmentation Fix
     json parsedJson;
     in >> parsedJson;
 
@@ -775,7 +775,7 @@ bool ItemManager::importFromFile_Binary(const std::string& filename) {
         LOG_CONTEXT(LogLevel::ERR, "Cannot open binary file '" + filename + "' for reading.", false);
         return false;
     }
-   std::lock_guard<std::mutex> lock(mutex_)
+   std::lock_guard<std::mutex> lock(mutex_);
     undoHistory.push_back(cloneCurrentState());
     redoQueue = {};
     items.clear();