Reimplement ACE_Based::LockedQueue as SQL holder for the SqlTransaction class, since std::queue is not safe when multiple threads are reading/writing to it at the same time (SqlDelayThread and a MapUpdate Thread).

Original patch by thenecromancer, was removed for ungrounded reasons.
Thanks to Zor for the insight.
Please give feedback on how this affects mtmaps usage.

--HG--
branch : trunk

2 files changed, 7 insertions, 11 deletions

diff --git a/src/shared/Database/SqlOperations.cpp b/src/shared/Database/SqlOperations.cpp
index 09f3e30466e..c766d6ca21d 100644
--- a/src/shared/Database/SqlOperations.cpp
+++ b/src/shared/Database/SqlOperations.cpp
@@ -33,23 +33,18 @@ void SqlStatement::Execute(Database *db)
 
 void SqlTransaction::Execute(Database *db)
 {
-    if (m_queue.empty())
-        return;
+    const char* sql;
 
     db->DirectExecute("START TRANSACTION");
-    while (!m_queue.empty())
+    while (m_queue.next(sql))
     {
-        char const *sql = m_queue.front();
-        m_queue.pop();
-
         if (!db->DirectExecute(sql))
         {
             free((void*)const_cast<char*>(sql));
             db->DirectExecute("ROLLBACK");
-            while (!m_queue.empty())
+            while (m_queue.next(sql))
             {
-                free((void*)const_cast<char*>(m_queue.front()));
-                m_queue.pop();
+                free((void*)const_cast<char*>(sql));
             }
             return;
         }
diff --git a/src/shared/Database/SqlOperations.h b/src/shared/Database/SqlOperations.h
index 0a54af70ffb..dcdada9cb59 100644
--- a/src/shared/Database/SqlOperations.h
+++ b/src/shared/Database/SqlOperations.h
@@ -57,11 +57,12 @@ class SqlStatement : public SqlOperation
 
 class SqlTransaction : public SqlOperation
 {
+        typedef ACE_Based::LockedQueue<const char *, ACE_Thread_Mutex> LockedQueue;
     private:
-        std::queue<const char *> m_queue;
+        LockedQueue m_queue;
     public:
         SqlTransaction() {}
-        void DelayExecute(const char *sql) { m_queue.push(strdup(sql)); }
+        void DelayExecute(const char *sql) { m_queue.add(strdup(sql)); }
         void Execute(Database *db);
 };