Receiving Bluetooth sensor data frames in Meshlium

This code example has been tested and improved to be executed in Meshlium with the data coming from a Wireless Sensor Network created with Waspmote.

This program reads through a serial port the information incoming from a Bluetooth Serial Port device.

File:
"sniffer.c"

Compilation on Meshlium:
gcc sniffer.c -o sniffer

Usage:
sniffer rfcomm0 38400

Note:
Serial port speed should be set on sniffer execution.

Code

/*
 *  Copyright (C) 2008 Libelium Comunicaciones Distribuidas S.L.
 *  http://www.libelium.com
 *
 *  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 2 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 <http://www.gnu.org/licenses/>.
 *
 *  Version 0.1
 *  Author: Octavio Benedi Sanchez
 */


#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <stdlib.h>
#include <termios.h> /* Terminal control library (POSIX) */

#define MAX 100

int main(int argc, char *argv[]) {
    int sd = 3;
    char *serialPort = "";
    char *BTserialPort0 = "/dev/rfcomm0";
    char *BTserialPort1 = "/dev/rfcomm1";
    char *BTserialPort2 = "/dev/rfcomm2";
    char valor[MAX] = "";
    char c;
    struct termios opciones;
    char *bt0 = "rfcomm0";
    char *bt1 = "rfcomm1";
    char *bt2 = "rfcomm2";

    int speed = B19200;

    typedef struct {
        char *name;
        int flag;
    } speed_spec;

    speed_spec speeds[] ={
        {"1200", B1200},
        {"2400", B2400},
        {"4800", B4800},
        {"9600", B9600},
        {"19200", B19200},
        {"38400", B38400},
        {"57600", B57600},
        {"115200", B115200},
        {NULL, 0}
    };

    if ((argc != 2) && (argc != 3)) {
        fprintf(stderr, "Usage: %s port\nOr: %s port speed\nDefault speed value is 19200\nAllowed ports: rfcomm0 rfcomm1 rfcomm2\nAllowed speed values: 1200 2400 4800 9600 19200 38400 57600 115200\n", argv[0], argv[0]);
        fprintf(stderr, "Author: Octavio Benedi Sanchez\n");
        exit(0);
    }
    if (argc == 3) {
        speed_spec *s;
        for (s = speeds; s->name; s++) {
            if (strcmp(s->name, argv[2]) == 0) {
                speed = s->flag;
                fprintf(stderr, "setting speed %s\n", s->name);
                break;
            }
        }
    }

    if (!strcmp(argv[1], bt0)) {
        //fprintf(stderr,"rfcomm0 chosen\n...");
        serialPort = BTserialPort0;
    }
    if (!strcmp(argv[1], bt1)) {
        //fprintf(stderr,"rfcomm1 chosen\n...");
        serialPort = BTserialPort1;
    }
    if (!strcmp(argv[1], bt2)) {
        //fprintf(stderr,"rfcomm2 chosen\n...");
        serialPort = BTserialPort2;
    }
    if (!strcmp(serialPort, "")) {
        fprintf(stderr, "Choose a valid port (rfcomm0, rfcomm1, rfcomm2)\n");
        exit(0);
    }

    if ((sd = open(serialPort, O_RDWR | O_NOCTTY | O_NONBLOCK)) == -1) {
        fprintf(stderr, "Unable to open the serial port %s - \n", serialPort);
        exit(-1);
    } else {
        if (!sd) {
            /*Sometimes the first time you call open it does not return the
             * right value (3) of the free file descriptor to use, for this
             * reason you can set manually the sd value to 3 or call again
             * the open function (normally returning 4 to sd), advised!*/
            sd = open(serialPort, O_RDWR | O_NOCTTY | O_NONBLOCK);
        }
        //fprintf(stderr,"Serial Port open at: %i\n", sd);
        fcntl(sd, F_SETFL, 0);
    }
    tcgetattr(sd, &opciones);
    cfsetispeed(&opciones, speed);
    cfsetospeed(&opciones, speed);
    opciones.c_cflag |= (CLOCAL | CREAD);
    /*No parity*/
    opciones.c_cflag &= ~PARENB;
    opciones.c_cflag &= ~CSTOPB;
    opciones.c_cflag &= ~CSIZE;
    opciones.c_cflag |= CS8;
    /*raw input:
     * making the applycation ready to receive*/
    opciones.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG);
    /*Ignore parity errors*/
    opciones.c_iflag |= ~(INPCK | ISTRIP | PARMRK);
    opciones.c_iflag |= IGNPAR;
    opciones.c_iflag &= ~(IXON | IXOFF | IXANY | IGNCR | IGNBRK);
    opciones.c_iflag |= BRKINT;
    /*raw output
     * making the applycation ready to transmit*/
    opciones.c_oflag &= ~OPOST;
    /*aply*/
    tcsetattr(sd, TCSANOW, &opciones);
    int j = 0;
    while (1) {
        read(sd,&c,1);
        valor[j]=c;
        j++;

        //We start filling the string untill the end of line char arrives
        //or we reach the end of the string. Then we write it on the screen.

        if((c=='\n') || (j==(MAX-1)))
        {
            int x;
            for(x=0;x<j;x++)
            {
                write(2,&valor[x],1);
                valor[x]='\0';
            }
            j=0;
        }
    }
    close(sd);
}

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