/* * Copyright © 2008-2010 Stéphane Raimbault * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include #include #include #include #include int main(void) { int socket; modbus_t *ctx; modbus_mapping_t *mb_mapping; ctx = modbus_new_tcp("127.0.0.1", 1502); /* modbus_set_debug(ctx, TRUE); */ mb_mapping = modbus_mapping_new(500, 500, 500, 500); if (mb_mapping == NULL) { fprintf(stderr, "Failed to allocate the mapping: %s\n", modbus_strerror(errno)); modbus_free(ctx); return -1; } socket = modbus_tcp_listen(ctx, 1); modbus_tcp_accept(ctx, &socket); for (;;) { uint8_t query[MODBUS_TCP_MAX_ADU_LENGTH]; int rc; rc = modbus_receive(ctx, query); if (rc != -1) { /* rc is the query size */ modbus_reply(ctx, query, rc, mb_mapping); } else { /* Connection closed by the client or error */ break; } } printf("Quit the loop: %s\n", modbus_strerror(errno)); modbus_mapping_free(mb_mapping); modbus_close(ctx); modbus_free(ctx); return 0; }