net.c

/* Rhizo-connector: A connector to different HF modems
 * Copyright (C) 2018 Rhizomatica
 * Author: Rafael Diniz <rafael@riseup.net>
 *
 * This 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, or (at your option)
 * any later version.
 *
 * This software 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 software; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 *
 * Network related functions
 */

/**
 * @file net.c
 * @author Rafael Diniz
 * @date 12 Apr 2018
 * @brief File containing network related functions
 *
 * For the sake of reusable and clean code, some network related functions.
 *
 */

#include <stdint.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include "net.h"

bool tcp_connect(char *ip, int port, int *sockt){
    struct sockaddr_in ardop_addr;

    *sockt = socket(PF_INET, SOCK_STREAM, 0);

    ardop_addr.sin_family = AF_INET;
    ardop_addr.sin_port = htons(port);
    ardop_addr.sin_addr.s_addr = inet_addr(ip);
    if (ardop_addr.sin_addr.s_addr == INADDR_NONE){
        fprintf(stderr, "Invalid IP address.\n");
        return false;
    }

    memset(ardop_addr.sin_zero, 0, sizeof(ardop_addr.sin_zero));

    if (connect(*sockt, (struct sockaddr *) &ardop_addr, sizeof(ardop_addr)) != 0)
        return false;

    return true;
}

bool tcp_read(int sockt, uint8_t *buffer, size_t rx_size){
    ssize_t len;
    size_t rcv_counter = 0;

    while (rcv_counter < rx_size){
        int trx_size = (rx_size - rcv_counter > TCP_BLOCK)? TCP_BLOCK : rx_size - rcv_counter;

        len = recv(sockt, buffer + rcv_counter, trx_size, 0);
        if (len == 0){
            fprintf(stderr, "tcp_read: socket read error.\n");
            return false;
        }
        rcv_counter += len;
    }

    return true;
}

bool tcp_write(int sockt, uint8_t *buffer, size_t tx_size){
    size_t len = send(sockt, buffer, tx_size, 0);
    if (len != tx_size) {
        fprintf(stderr, "tcp_write: socket write error.\n");
        return false;
    }

    return true;
}