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/*

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 * Copyright (c) 2002,2016 Mario de Sousa (msousa@fe.up.pt)

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 *

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 * This file is part of the Modbus library for Beremiz and matiec.

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 *

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 * This Modbus library is free software: you can redistribute it and/or modify

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 * it under the terms of the GNU Lesser General Public License as published by

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 * the Free Software Foundation, either version 3 of the License, or

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 * (at your option) any later version.

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 *

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 * This program is distributed in the hope that it will be useful, but

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 * WITHOUT ANY WARRANTY; without even the implied warranty of

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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser 

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 * General Public License for more details.

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 *

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 * You should have received a copy of the GNU Lesser General Public License

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 * along with this Modbus library.  If not, see <http://www.gnu.org/licenses/>.

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 *

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 * This code is made available on the understanding that it will not be

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 * used in safety-critical situations without a full and competent review.

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 */

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#ifndef MODBUS_TCP_PRIVATE_H

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#define MODBUS_TCP_PRIVATE_H

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#include "mb_util.h"

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/* tcp port default configuration... */

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#define DEF_SERVICE  "502"        /* port used by modbus */

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#define DEF_PROTOCOL "tcp"        /* protocol used by modbus tcp */

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#define DEF_TYPE     SOCK_STREAM  /* Quality of service required of the socket... */

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#define DEF_MAX_PENDING_CONNECTION_REQUESTS 5

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                                  /* maximum number of pending connection requests

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                                   * that have not yet been accept()'ed

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                                   */

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#define DEF_CLOSE_ON_SILENCE 1    /* Used only by master nodes.

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                                   * Flag indicating whether, by default, the connection

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                                   * to the slave device should be closed whenever the

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                                   * modbus_tcp_silence_init() function is called.

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                                   *

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                                   * 0  -> do not close connection

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                                   * >0 -> close connection

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                                   *

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                                   * The spec sugests that connections that will not

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                                   * be used for longer than 1 second should be closed.

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                                   * Even though we expect most connections to have

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                                   * silence intervals much shorted than 1 second, we

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                                   * decide to use the default of shuting down the

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                                   * connections because it is safer, and most other

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                                   * implementations seem to do the same.

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                                   * If we do not close we risk using up all the possible

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                                   * connections that the slave can simultaneouly handle,

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                                   * effectively locking out every other master that

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                                   * wishes to communicate with that same slave.

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                                   */

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 /* Since the receive buffer is also re-used to store the frame header,

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  * we set it to the larger of the two.

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  */

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#if     TCP_HEADER_LENGTH > MAX_L2_FRAME_LENGTH

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#define RECV_BUFFER_SIZE    TCP_HEADER_LENGTH

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#else

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#define RECV_BUFFER_SIZE    MAX_L2_FRAME_LENGTH

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#endif

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#endif  /* MODBUS_TCP_PRIVATE_H */

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