System.Data.SQLite

  internal delegate void SQLiteLogCallback(IntPtr puser, int err_code, IntPtr message);

  /// <summary>
  /// This class implements SQLiteBase completely, and is the guts of the code that interop's SQLite with .NET
  /// </summary>
  internal class SQLite3 : SQLiteBase
  {
    private static object syncRoot = new object();

    //
    // NOTE: This is the public key for the System.Data.SQLite assembly.  If you change the
    //       SNK file, you will need to change this as well.
    //
    internal const string PublicKey =
        "002400000480000094000000060200000024000052534131000400000100010005a288de5687c4e1" +
        "b621ddff5d844727418956997f475eb829429e411aff3e93f97b70de698b972640925bdd44280df0" +

    /// </summary>
    /// <returns>
    /// A boolean indicating whether or not the SQLite core library has been
    /// initialized for the current process.
    /// </returns>
    internal static bool StaticIsInitialized()
    {
        //
        // BUGFIX: Prevent races with other threads for this entire block, due
        //         to the try/finally semantics.  See ticket [72905c9a77].
        //
        lock (syncRoot)
        {
#if !PLATFORM_COMPACTFRAMEWORK
            //
            // NOTE: Save the state of the logging class and then restore it
            //       after we are done to avoid logging too many false errors.
            //
            bool savedEnabled = SQLiteLog.Enabled;
            SQLiteLog.Enabled = false;

            try
            {
#endif
                //
                // NOTE: This method [ab]uses the fact that SQLite will always
                //       return SQLITE_ERROR for any unknown configuration option
                //       *unless* the SQLite library has already been initialized.
                //       In that case it will always return SQLITE_MISUSE.
                //
                int rc = UnsafeNativeMethods.sqlite3_config(
                    (int)SQLiteConfigOpsEnum.SQLITE_CONFIG_NONE, null, (IntPtr)0);

                return (rc == /* SQLITE_MISUSE */ 21);
#if !PLATFORM_COMPACTFRAMEWORK
            }
            finally
            {
                SQLiteLog.Enabled = savedEnabled;
            }
#endif
        }
    }

    /// <summary>
    /// Helper function to retrieve a column of data from an active statement.
    /// </summary>
    /// <param name="stmt">The statement being step()'d through</param>
    /// <param name="index">The column index to retrieve</param>