ODBC-395 The fix and the testcase

There was some old mess with connection object properties for isolation
level, and for setting initial level on connection was used the worng
one, that did not get the value of the attribute. The patch removed that
bogus field and left only one of them.

ma_connection.c

@@ -816,11 +816,11 @@ SQLRETURN MADB_DbcConnectDB(MADB_Dbc *Connection,
   }
 
   /* Set isolation level */
-  if (Connection->IsolationLevel)
+  if (Connection->TxnIsolation)
   {
     for (i = 0; i < 4; i++)
     {
-      if (MADB_IsolationLevel[i].SqlIsolation == Connection->IsolationLevel)
+      if (MADB_IsolationLevel[i].SqlIsolation == Connection->TxnIsolation)
       {
         _snprintf(StmtStr, sizeof(StmtStr), "SET SESSION TRANSACTION ISOLATION LEVEL %s",
           MADB_IsolationLevel[i].StrIsolation);

ma_odbc.h

@@ -380,7 +380,6 @@ struct st_ma_odbc_connection
   SQLUINTEGER WriteTimeout;
   SQLUINTEGER PacketSize;
   SQLINTEGER  AccessMode;
-  SQLINTEGER  IsolationLevel;     /* tx_isolation */
   SQLUINTEGER Trace;
   unsigned int LoginTimeout; /* The attribute is SQLUINTEGER, that is unsigned long, that technically can be 8bytes
                                 (not sure how does other DM define it) But C/C option is unsigned int */

test/basic.c

@@ -1118,11 +1118,11 @@ ODBC_TEST(t_bug31959)
 
   if (ServerNotOlderThan(Connection, 11, 1, 1))
   {
-    CHECK_STMT_RC(Stmt, SQLPrepare(Stmt, (SQLCHAR *)"select @@transaction_isolation", SQL_NTS));
+    CHECK_STMT_RC(Stmt, SQLPrepare(Stmt, (SQLCHAR *)"SELECT @@transaction_isolation", SQL_NTS));
   }
   else
   {
-    CHECK_STMT_RC(Stmt, SQLPrepare(Stmt, (SQLCHAR *)"select @@tx_isolation", SQL_NTS));
+    CHECK_STMT_RC(Stmt, SQLPrepare(Stmt, (SQLCHAR *)"SELECT @@tx_isolation", SQL_NTS));
   }
 
   /* check all 4 valid isolation levels */

test/tran.c

@@ -208,13 +208,54 @@ ODBC_TEST(t_isolation2)
   return OK;
 }
 
+/* Testing, that setting of isolation level before connection establishing works
+ * This covers also the case of ODBC-395
+ */
+ODBC_TEST(t_isolation3)
+{
+  SQLINTEGER isolation= 0;
+  SQLHANDLE dbc= NULL, Stmt1= NULL;
+  char buffer[32];
+
+  IS(AllocEnvConn(&Env, &dbc));
+
+ /* Setting different level(SQL_TXN_READ_COMMITTED) */
+  CHECK_DBC_RC(dbc, SQLSetConnectAttr(dbc, SQL_ATTR_TXN_ISOLATION,
+    (SQLPOINTER)SQL_TXN_READ_COMMITTED, 0));
+  /* We don't need statement, but it's easier to connect this way :), let's neglect, that the error may be in fact stmt allocation error */
+  Stmt1= DoConnect(dbc, FALSE, NULL, NULL, NULL, 0, NULL, 0, NULL, NULL);
+  FAIL_IF(Stmt1 == NULL, "Could not connect and/or allocate statement");
+
+  /* Checking that after connection we have that isolation level */
+  CHECK_DBC_RC(dbc, SQLGetConnectAttr(dbc, SQL_ATTR_TXN_ISOLATION, &isolation,
+    SQL_IS_POINTER, NULL));
+  is_num(isolation, SQL_TXN_READ_COMMITTED);
+
+  if (ServerNotOlderThan(Connection, 11, 1, 1))
+  {
+    OK_SIMPLE_STMT(Stmt1, "SELECT @@transaction_isolation");
+  }
+  else
+  {
+    OK_SIMPLE_STMT(Stmt1, "SELECT @@tx_isolation");
+  }
+
+  CHECK_STMT_RC(Stmt1, SQLFetch(Stmt1));
+  IS_STR("READ-COMMITTED", my_fetch_str(Stmt1, buffer, 1), sizeof("READ-COMMITTED"));
+  CHECK_STMT_RC(Stmt1, SQLFreeStmt(Stmt1, SQL_DROP));
+  CHECK_DBC_RC(dbc, SQLDisconnect(dbc));
+  CHECK_DBC_RC(dbc, SQLFreeConnect(dbc));
+
+  return OK;
+}
 
 MA_ODBC_TESTS my_tests[]=
 {
   {my_transaction,"my_transaction"},
   {t_tran, "t_tran"},
   {t_isolation, "t_isolation"},
   {t_isolation2, "t_isolation2_value_change_tracking"},
+  {t_isolation3, "t_isolation3_set_before_connect"},
   {NULL, NULL}
 };