Exemplo n.º 1
0
        /// <summary>
        /// Opens the physical connection to the server.
        /// </summary>
        /// <remarks>Usually called by the RequestConnector
        /// Method of the connection pool manager.</remarks>
        internal void Open()
        {
            ServerVersion = null;
            // If Connection.ConnectionString specifies a protocol version, we will
            // not try to fall back to version 2 on failure.

            // Reset state to initialize new connector in pool.
            CurrentState = NpgsqlClosedState.Instance;

            // Get a raw connection, possibly SSL...
            CurrentState.Open(this);
            try
            {
                // Establish protocol communication and handle authentication...
                CurrentState.Startup(this);
            }
            catch (NpgsqlException)
            {
                throw;
            }

            // Change the state of connection to open and ready.
            State        = ConnectionState.Open;
            CurrentState = NpgsqlReadyState.Instance;

            // Fall back to the old way, SELECT VERSION().
            // This should not happen for protocol version 3+.
            if (ServerVersion == null)
            {
                using (NpgsqlCommand command = new NpgsqlCommand("set DATESTYLE TO ISO;select version();", this))
                {
                    ServerVersion = new Version(PGUtil.ExtractServerVersion((string)command.ExecuteScalar()));
                }
            }

            StringBuilder sbInit = new StringBuilder();

            // Adjust client encoding.
            NpgsqlParameterStatus clientEncodingParam = null;

            if (!ServerParameters.TryGetValue("client_encoding", out clientEncodingParam) ||
                !string.Equals(clientEncodingParam.ParameterValue, "UTF8", StringComparison.OrdinalIgnoreCase) && !string.Equals(clientEncodingParam.ParameterValue, "UNICODE", StringComparison.OrdinalIgnoreCase))
            {
                sbInit.AppendLine("SET CLIENT_ENCODING TO UTF8;");
            }

            if (!string.IsNullOrEmpty(settings.SearchPath))
            {
                // TODO: Add proper message when finding a semicolon in search_path.
                // This semicolon could lead to a sql injection security hole as someone could write in connection string:
                // searchpath=public;delete from table; and it would be executed.

                if (settings.SearchPath.Contains(";"))
                {
                    throw new InvalidOperationException();
                }

                sbInit.AppendLine("SET SEARCH_PATH=" + settings.SearchPath + ";");
            }

            if (!string.IsNullOrEmpty(settings.ApplicationName))
            {
                if (!SupportsApplicationName)
                {
                    //TODO
                    //throw new InvalidOperationException(resman.GetString("Exception_ApplicationNameNotSupported"));
                    throw new InvalidOperationException("ApplicationName not supported.");
                }

                if (settings.ApplicationName.Contains(";"))
                {
                    throw new InvalidOperationException();
                }

                sbInit.AppendLine("SET APPLICATION_NAME='" + settings.ApplicationName.Replace('\'', '-') + "';");
            }

            /*
             * Try to set SSL negotiation to 0. As of 2010-03-29, recent problems in SSL library implementations made
             * postgresql to add a parameter to set a value when to do this renegotiation or 0 to disable it.
             * Currently, Npgsql has a problem with renegotiation so, we are trying to disable it here.
             * This only works on postgresql servers where the ssl renegotiation settings is supported of course.
             * See http://lists.pgfoundry.org/pipermail/npgsql-devel/2010-February/001065.html for more information.
             */
            sbInit.AppendLine("SET ssl_renegotiation_limit=0;");

            /*
             * Set precision digits to maximum value possible. For postgresql before 9 it was 2, after that, it is 3.
             * This way, we set first to 2 and then to 3. If there is an error because of 3, it will have been set to 2 at least.
             * Check bug report #1010992 for more information.
             */
            sbInit.AppendLine("SET extra_float_digits=3;");
            try
            {
                new NpgsqlCommand(sbInit.ToString(), this).ExecuteBlind();
            }
            catch
            {
                foreach (var line in sbInit.ToString().Split(Environment.NewLine.ToCharArray()))
                {
                    try
                    {
                        if (line.Length > 0)
                        {
                            new NpgsqlCommand(line, this).ExecuteBlind();
                        }
                    }
                    catch { }
                }
            }

            // Make a shallow copy of the type mapping that the connector will own.
            // It is possible that the connector may add types to its private
            // mapping that will not be valid to another connector, even
            // if connected to the same backend version.
            _oidToNameMapping = NpgsqlTypesHelper.CreateAndLoadInitialTypesMapping(this).Clone();

            ProcessServerVersion();

            // The connector is now fully initialized. Beyond this point, it is
            // safe to release it back to the pool rather than closing it.
            IsInitialized = true;
        }