Regression in MyODBC 3.51.12

Problem:
==========
There's a regression in MyODBC 3.51.12 vs. 3.51.10.


Details:
==========
Using MyODBC with .Net, the OdbcConnection.ConnectionState property no longer 
correctly reflects the connection's state.
(It seems to be a side effect of the removal of auto-reconnection logic in 
MyODBC.)


How to reproduce:
===================

Test app (C#):
---------------
using System;
using System.Data;
using System.Data.Odbc;

class MySqlConnectTest {
        static string user = "INSERT USER HERE";
        static string password = "INSERT PASSWORD HERE";
        static string server = "INSERT SERVER HERE";

        static OdbcCommand connect() {
                string c = "Driver={MySQL ODBC 3.51 Driver};Server=" + server + 
";Uid=" + user + ";Pwd=" + password + ";OPTION=3";
                OdbcConnection conn = new OdbcConnection(c);
                conn.Open();
                OdbcCommand cmd = conn.CreateCommand();
                cmd.CommandText = "SELECT VERSION()";
                return cmd;
        }

        static void Main(string[] args) {
                OdbcCommand cmd;

                Console.Out.WriteLine("Opening connection...");
                cmd = connect();
                cmd.ExecuteNonQuery();

                Console.Out.WriteLine("Ok.  Kill database or connection now, 
then press Enter.");
                Console.In.ReadLine();

                // Simulate a continuously running program that use only 1 
connection=.
                for (int i = 5; i > 0; i--) {
                        try {
                                if ((cmd.Connection.State | 
ConnectionState.Open) == ConnectionState.Open)
                                        Console.Out.WriteLine("Connection state 
'" + cmd.Connection.State + "' - executing query.");
                                else {
                                        Console.Out.WriteLine("Connection state 
'" + cmd.Connection.State + "', opening and executing query.");
                                        cmd = connect();
                                }
                                cmd.ExecuteNonQuery();
                        } catch (Exception e) {
                                Console.Out.WriteLine("Error: " + e.Message + 
"\n");
                        }
                }
                Console.Out.WriteLine("\nDone - press Enter.");
                Console.In.ReadLine();
        }
}
---------------

The above test application is similar to application logic that we use to 
recreate a connection when it has been closed behind our back for one reason or 
another.

You will probably find TCPView from Sysinternals (http://www.sysinternals.com) 
handy to simulate a database restart.

1. Compile above C# code with fx. csc.exe.
2. Install MyODBC 3.51.10 or 3.51.12 (run the test once with both).
3. Run test application
4. When it says "kill connection now", use TCPView to close the connection.
5. Observe the difference in behaviour.....


Test results:
===============

MyODBC 3.51.10:
----------------
X:\>MySqlConnectTest.exe
Opening connection...
Ok.  Kill database or connection now, then press Enter.
[ Note: killed connection here ]

Connection state 'Open' - executing query.
Connection state 'Open' - executing query.
Connection state 'Open' - executing query.
Connection state 'Open' - executing query.
Connection state 'Open' - executing query.

Done - press Enter.
----------------

Seems MyODBC 3.51.10 reconnects behind our back.
ConnectionState is (correctly) == ConnectionState.Open.

MyODBC 3.51.12:
----------------
X:\>MySqlConnectTest.exe
Opening connection...
Ok.  Kill database or connection now, then press Enter.
[ Note: killed connection here ]

Connection state 'Open' - executing query.
Error: ERROR [HYT00] [MySQL][ODBC 3.51 Driver][mysqld-4.1.9-standard-log]MySQL 
server has gone away

Connection state 'Open' - executing query.
Error: ERROR [HYT00] [MySQL][ODBC 3.51 Driver][mysqld-4.1.9-standard-log]MySQL 
server has gone away

Connection state 'Open' - executing query.
Error: ERROR [HYT00] [MySQL][ODBC 3.51 Driver][mysqld-4.1.9-standard-log]MySQL 
server has gone away

Connection state 'Open' - executing query.
Error: ERROR [HYT00] [MySQL][ODBC 3.51 Driver][mysqld-4.1.9-standard-log]MySQL 
server has gone away

Connection state 'Open' - executing query.
Error: ERROR [HYT00] [MySQL][ODBC 3.51 Driver][mysqld-4.1.9-standard-log]MySQL 
server has gone away

Done - press Enter.
----------------

Seems MyODBC 3.51.12 does _not_ reconnect behind our back.
ConnectionState is (incorrectly) still == ConnectionState.Open.


Workaround:
=============
We've implemented our own ConnectionState mechanism instead of using MyODBC's.


Proposed solution:
====================
I'm imagining that ConnectionState should say "Closed" when the connection has 
died behind our back.

The .Net documentation says:
"Calling the State property on an open connection increases application 
overhead because each such call results in a SQL_ATTR_CONNECTION_DEAD call to 
the underlying ODBC driver to determine if the connection is still valid."

If the assumption is not valid (which IMHO renders ConnectionState somewhat 
useless), the SQL_ATTR_CONNECTION_DEAD behaviour should at least be documented 
to be "weird".

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