writenoncanonical.c v2

/*Non-Canonical Input Processing*/

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <termios.h>
#include <stdio.h>
#include <string.h>

#define BAUDRATE B38400
#define MODEMDEVICE "/dev/ttyS0"
#define _POSIX_SOURCE 1 /* POSIX compliant source */
#define FALSE 0
#define TRUE 1
#define F 0x7e
#define A 0x03
#define S 0x03
#define U 0x07

volatile int STOP=FALSE;

int main(int argc, char** argv)
{
    system("clear");
 // CREATING TRAMA
    unsigned char setup[5];
    setup[0]=F;
    setup[1]=A;
    setup[2]=S;
    setup[3]=setup[1]^setup[2];
    setup[4]=F;


    int fd,c, res;

    struct termios oldtio,newtio;
    int i=0, sum = 0, speed = 0;

    /*if ( (argc < 2) ||
         ((strcmp("/dev/ttyS0", argv[1])!=0) &&
          (strcmp("/dev/ttyS1", argv[1])!=0) )) {
      printf("Usage:\tnserial SerialPort\n\tex: nserial /dev/ttyS1\n");
      exit(1);
    }/*


  /*
    Open serial port device for reading and writing and not as controlling tty
    because we don't want to get killed if linenoise sends CTRL-C.
  */


    fd = open(MODEMDEVICE, O_RDWR | O_NOCTTY | O_NONBLOCK);
    if (fd <0) {perror(argv[1]); exit(-1); }

    if ( tcgetattr(fd,&oldtio) == -1) { /* save current port settings */
      perror("tcgetattr");
      exit(-1);
    }

    bzero(&newtio, sizeof(newtio));
    newtio.c_cflag = BAUDRATE | CS8 | CLOCAL | CREAD;
    newtio.c_iflag = IGNPAR;
    newtio.c_oflag = 0;

    /* set input mode (non-canonical, no echo,...) */
    newtio.c_lflag = 0;

    newtio.c_cc[VTIME]    = 3;   /* inter-character timer unused */
    newtio.c_cc[VMIN]     = 1;   /* blocking read until 5 chars received */




  /*
    VTIME e VMIN devem ser alterados de forma a proteger com um temporizador a
    leitura do(s) próximo(s) caracter(es)

  */



    tcflush(fd, TCIOFLUSH);

    if ( tcsetattr(fd,TCSANOW,&newtio) == -1) {
      perror("tcsetattr");
      exit(-1);
    }





  /*
    O ciclo FOR e as instruções seguintes devem ser alterados de modo a respeitar
    o indicado no guião
  */




    printf("New termios structure set(Receiving Message)\n");

    unsigned char msg;
    char UA[5];
    int aux=0;
    int counter=0;
    int sendAgain=1;
    int state;
    int done=0;
    int msgsent=0;
    int res2;


    for(counter ; counter < 3; counter++){
        printf("%s%d\n" ,"Sending data. Try# " , counter+1);
            res = write(fd,setup,5);
        state=0;
        while (state < 5 )
            {
                  res2 = read(fd,&msg,1);
              if(res2 == -1){
                sleep(3);
                break;
                  }
              else msgsent=1;

                    switch (state)
                    {
                            case 0:
                        if (msg == F){
                        UA[state]=msg;
                        state++;
                        }

                                    break;
                            case 1:
                                    if (msg == A){
                        UA[state]=msg;
                        state++;
                        }

                                            else if(msg != A && msg !=F) state--;

                        break;

                            case 2:
                                    if (msg == U){
                        UA[state]=msg;
                        state++;
                        }

                                            else if(msg == F) state--;

                                            else state=0;

                        break;
                            case 3:
                                    if (msg == (A^U)){
                        UA[state]=msg;
                        state++;
                        }

                        else state=0;

                                    break;
                            case 4:
                                    if (msg == F){
                        UA[state]=msg;
                        state++;
                        done=1;
                        }

                                            else state=0;

                                    break;
                    }

            }
        if(done) break;
          }

    if(msgsent == 0 ) printf("Could not send any message. UA not received");
    else {
        for(;aux < 5; aux++){
                printf("%x \n", UA[aux]);
        }
          }





    if ( tcsetattr(fd,TCSANOW,&oldtio) == -1) {
      perror("tcsetattr");
      exit(-1);
    }
    close(fd);
    return 0;
}