// 466stream.c
// Adam MacBeth

#include <string.h>
#include <stdio.h>
#include <stdlib.h>

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

#define BAUDRATE B9600
#define DEFAULT_PORT 3
#define DEVICE_PREFIX "/dev/com"

int main(int argc, char* argv[])
{
        int fd,err,portnum;
	int note;
	char portname[30];
	char hex_note[2];
	struct termios oldtio,newtio;
	FILE *input_file;

	if(argc < 3) {
		printf("Usage: 466stream [-portnum] filename\n");
		exit(1);
	}
	if(argv[1][0] == '-')
		portnum = atoi(&argv[1][1]);	
	else portnum = DEFAULT_PORT;	

	input_file = fopen(argv[argc-1],"r");
	if(input_file == NULL) {
	  printf("File '%s' does not exist.\n", argv[argc-1]);
	  exit(1);
	}
	
	sprintf(portname, "%s%d", DEVICE_PREFIX, portnum);
	printf("Using COM%d (%s)\n", portnum, portname);

	fd = open(portname, O_RDWR | O_NOCTTY);
	if(fd < 0){
	  printf("Error opening COM%d. Exiting...\n", portnum);
	  exit(1);
	}

	tcgetattr(fd,&oldtio); /* save current serial port settings */
	bzero(&newtio, sizeof(newtio)); /* clear struct for new port settings */

/* 
  BAUDRATE: Set bps rate. You could also use cfsetispeed and cfsetospeed.
  CRTSCTS : output hardware flow control (only used if the cable has
            all necessary lines. See sect. 7 of Serial-HOWTO)
  CS8     : 8n1 (8bit,no parity,1 stopbit)
  CLOCAL  : local connection, no modem contol
  CREAD   : enable receiving characters
*/
	newtio.c_cflag = BAUDRATE | CS8 | CLOCAL | CREAD;
 
/*
  IGNPAR  : ignore bytes with parity errors
  ICRNL   : map CR to NL (otherwise a CR input on the other computer
            will not terminate input)
  otherwise make device raw (no other input processing)
*/
	newtio.c_iflag = IGNPAR | ICRNL;
 
/*
 Raw output.
*/
	newtio.c_oflag = 0;

	newtio.c_lflag = 0;
 
	newtio.c_cc[VTIME]    = 0;     /* inter-character timer unused */
	newtio.c_cc[VMIN]     = 1;     /* blocking read until 1 character arrives */
	tcflush(fd, TCIFLUSH);
	tcsetattr(fd,TCSANOW,&newtio);
	
	err = write(fd,"s",1); /* signal streaming with 's' */
	if(err < 1) {
            printf("Error writing to port\n");
            goto End;
	}
	err = read(fd,&note,1);
	if(err < 1) {
	  printf("Error reading from port\n");
	  goto End;
	}
	while(1) {
	  hex_note[0] = fgetc(input_file);
	  if(hex_note[0] == EOF) break;
	  hex_note[1] = fgetc(input_file);
	  note = strtol(hex_note,(char **)NULL,16);
	  //printf("Writing to port...%d\n",note);
	  err = write(fd,&note,1);
	  if(err < 1) {
	    printf("Error writing to port\n");
	    goto End;
	  }
	  //printf("Reading from port...%d\n",note);
	  err = read(fd,&note,1);
	  if(err < 1) {
	    printf("Error reading from port\n");
	    goto End;
	  }
	}

	End: ;

	tcsetattr(fd,TCSANOW,&oldtio); /* restore old serial settings */
	exit(1);
	}