libmodbus/src/modbus-rtu-private.h

/*
 * Copyright © Stéphane Raimbault <stephane.raimbault@gmail.com>
 *
 * SPDX-License-Identifier: LGPL-2.1-or-later
 */

#ifndef MODBUS_RTU_PRIVATE_H
#define MODBUS_RTU_PRIVATE_H

#ifndef _MSC_VER
#include <stdint.h>
#else
#include "stdint.h"
#endif

#if defined(_WIN32)
#include <windows.h>
#else
#include <termios.h>
#endif

#define _MODBUS_RTU_HEADER_LENGTH     1
#define _MODBUS_RTU_PRESET_REQ_LENGTH 6
#define _MODBUS_RTU_PRESET_RSP_LENGTH 2

#define _MODBUS_RTU_CHECKSUM_LENGTH 2

#if defined(_WIN32)
#if !defined(ENOTSUP)
#define ENOTSUP WSAEOPNOTSUPP
#endif

/* WIN32: struct containing serial handle and a receive buffer */
#define PY_BUF_SIZE 512

struct win32_ser {
    /* File handle */
    HANDLE fd;
    /* Receive buffer */
    uint8_t buf[PY_BUF_SIZE];
    /* Received chars */
    DWORD n_bytes;
};
#endif /* _WIN32 */

typedef struct _modbus_rtu {
    /* Device: "/dev/ttyS0", "/dev/ttyUSB0" or "/dev/tty.USA19*" on Mac OS X. */
    char *device;
    /* Bauds: 9600, 19200, 57600, 115200, etc */
    int baud;
    /* Data bit */
    uint8_t data_bit;
    /* Stop bit */
    uint8_t stop_bit;
    /* Parity: 'N', 'O', 'E' */
    char parity;
#if defined(_WIN32)
    struct win32_ser w_ser;
    DCB old_dcb;
#else
    /* Save old termios settings */
    struct termios old_tios;
#endif
#if HAVE_DECL_TIOCSRS485
    int serial_mode;
#endif
#if HAVE_DECL_TIOCM_RTS
    int rts;
    int rts_delay;
    int onebyte_time;
    void (*set_rts)(modbus_t *ctx, int on);
#endif
    /* To handle many slaves on the same link */
    int confirmation_to_ignore;
} modbus_rtu_t;

#endif /* MODBUS_RTU_PRIVATE_H */