From b4cfd679ee595cef48dd7d0bb4c0c3eb0eee0e1c Mon Sep 17 00:00:00 2001
From: LDA <lda@ari.lt>
Date: Sun, 11 Aug 2024 10:38:36 +0200
Subject: [PATCH] [FIX/WIP] Fix concurrency problem with LMDB

---
 src/MatrixEventHandler.c | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/src/MatrixEventHandler.c b/src/MatrixEventHandler.c
index 51c0dc1..5f7cb1d 100644
--- a/src/MatrixEventHandler.c
+++ b/src/MatrixEventHandler.c
@@ -245,28 +245,31 @@ ParseeMessageHandler(ParseeData *data, HashMap *event)
 
     bool direct = false;
 
-    chat_id = ParseeGetFromRoomID(data, id);
-
-    ref = DbLock(data->db, 3, "rooms", id, "data");
-    json = DbJson(ref);
-    direct = JsonValueAsBoolean(HashMapGet(json, "is_direct"));
-
     if (ParseeIsPuppet(data->config, m_sender) || 
         ParseeManageBan(data, m_sender, id))
     {
-        DbUnlock(data->db, ref);
-        Free(chat_id);
         Free(reply_id);
         Free(xepd);
         Free(unedited_id);
         return;
     }
 
+    chat_id = ParseeGetFromRoomID(data, id);
+
+    /* TODO: This ref should be marked as read-only, 
+     * as LMDB doesn't seem to like having two concurrent RW 
+     * transactions running. */
+    ref = DbLock(data->db, 3, "rooms", id, "data");
+    json = JsonDuplicate(DbJson(ref));
+    direct = JsonValueAsBoolean(HashMapGet(json, "is_direct"));
+    DbUnlock(data->db, ref);
+    ref = NULL;
+
     if (!direct && !chat_id)
     {
         ParseeBotHandler(data, event);
 
-        DbUnlock(data->db, ref);
+        JsonFree(json);
         Free(chat_id);
         Free(reply_id);
         Free(xepd);
@@ -362,7 +365,7 @@ end:
     Free(unauth);
     Free(unedited_id);
 
-    DbUnlock(data->db, ref);
+    JsonFree(json);
 }
 
 void