DB Layer:

- Make SQL Transactions actual objects used in code. (Thanks to Derex for the idea)
* Uncommitted transactions will be automatically rolled back and cleaned up using ACE_Refcounted_Auto_Ptr, so no need to call Rollback() in the code.
* Prevents recursive transactions and makes developers aware of transactions going on.
* Gets rid of unneccesary overhead iterating over a concurrent map.
- Some cleanups in affected code, including better usage of transaction control in AH / mail related code to prevent data loss.

*** Experimental, use at own risk, recommended to backup your DBs. ***

--HG--
branch : trunk

1 files changed, 72 insertions, 0 deletions

diff --git a/src/server/shared/Database/Transaction.cpp b/src/server/shared/Database/Transaction.cpp
new file mode 100644
index 00000000000..a364728b2d0
--- /dev/null
+++ b/src/server/shared/Database/Transaction.cpp
@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2008-2010 Trinity <http://www.trinitycore.org/>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "Transaction.h"
+
+void Transaction::Append(const char* sql)
+{
+    m_queries.push(strdup(sql));
+}
+
+void Transaction::PAppend(const char* sql, ...)
+{
+    va_list ap;
+    char szQuery [MAX_QUERY_LEN];
+    va_start(ap, sql);
+    int res = vsnprintf(szQuery, MAX_QUERY_LEN, sql, ap);
+    va_end(ap);
+
+    Append(szQuery);
+}
+
+void Transaction::Cleanup()
+{
+    while (!m_queries.empty())
+    {
+        free((void*)const_cast<char*>(m_queries.front()));
+        m_queries.pop();
+    }
+}
+
+bool TransactionTask::Execute()
+{
+    std::queue<char*>& queries = m_trans->m_queries;
+    if (queries.empty())
+        return false;
+
+    const char* sql;
+
+    m_conn->BeginTransaction();
+    while (!queries.empty())
+    {
+        sql = queries.front();
+        if (!m_conn->Execute(sql))
+        {
+            free((void*)const_cast<char*>(sql));
+            queries.pop();
+            m_conn->RollbackTransaction();
+            return false;
+        }
+
+        free((void*)const_cast<char*>(sql));
+        queries.pop();
+    }
+
+    m_conn->CommitTransaction();
+    return true;
+}