tests/bandwidth-server-one.c

   1 /*
   2  * Copyright © Stéphane Raimbault <stephane.raimbault@gmail.com>
   3  *
   4  * SPDX-License-Identifier: BSD-3-Clause
   5  */
   6
   7 #include <stdio.h>
   8 #ifndef _MSC_VER
   9 #include <unistd.h>
  10 #endif
  11 #include <errno.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14
  15 #include <modbus.h>
  16
  17 #if defined(_WIN32)
  18 #define close closesocket
  19 #endif
  20
  21 enum {
  22     TCP,
  23     RTU
  24 };
  25
  26 int main(int argc, char *argv[])
  27 {
  28     int s = -1;
  29     modbus_t *ctx = NULL;
  30     modbus_mapping_t *mb_mapping = NULL;
  31     int rc;
  32     int use_backend;
  33
  34     /* TCP */
  35     if (argc > 1) {
  36         if (strcmp(argv[1], "tcp") == 0) {
  37             use_backend = TCP;
  38         } else if (strcmp(argv[1], "rtu") == 0) {
  39             use_backend = RTU;
  40         } else {
  41             printf("Usage:\n  %s [tcp|rtu] - Modbus client to measure data bandwidth\n\n",
  42                    argv[0]);
  43             exit(1);
  44         }
  45     } else {
  46         /* By default */
  47         use_backend = TCP;
  48     }
  49
  50     if (use_backend == TCP) {
  51         ctx = modbus_new_tcp("127.0.0.1", 1502);
  52         s = modbus_tcp_listen(ctx, 1);
  53         modbus_tcp_accept(ctx, &s);
  54
  55     } else {
  56         ctx = modbus_new_rtu("/dev/ttyUSB0", 115200, 'N', 8, 1);
  57         modbus_set_slave(ctx, 1);
  58         modbus_connect(ctx);
  59     }
  60
  61     mb_mapping =
  62         modbus_mapping_new(MODBUS_MAX_READ_BITS, 0, MODBUS_MAX_READ_REGISTERS, 0);
  63     if (mb_mapping == NULL) {
  64         fprintf(stderr, "Failed to allocate the mapping: %s\n", modbus_strerror(errno));
  65         modbus_free(ctx);
  66         return -1;
  67     }
  68
  69     for (;;) {
  70         uint8_t query[MODBUS_TCP_MAX_ADU_LENGTH];
  71
  72         rc = modbus_receive(ctx, query);
  73         if (rc > 0) {
  74             modbus_reply(ctx, query, rc, mb_mapping);
  75         } else if (rc == -1) {
  76             /* Connection closed by the client or error */
  77             break;
  78         }
  79     }
  80
  81     printf("Quit the loop: %s\n", modbus_strerror(errno));
  82
  83     modbus_mapping_free(mb_mapping);
  84     if (s != -1) {
  85         close(s);
  86     }
  87     /* For RTU, skipped by TCP (no TCP connect) */
  88     modbus_close(ctx);
  89     modbus_free(ctx);
  90
  91     return 0;
  92 }