/*                      - GETCHAR.C -

  The ANSI "getchar" function delivered here is supposed to be tailored
  for the actual target hardware.  This version of getchar contains a simple
  line-editor that can back-space and delete  (In_DELETE), skip line and
  start over again (In_SKIP), as well as recognize end of file (In_EOF).

  $Revision: 38615 $

   Copyright 1986 - 1999 IAR Systems. All rights reserved.
*/

#include <stdio.h>
#include "msp430x54x.h"

_STD_BEGIN

// My low level get function
char _low_level_get(void){
 
  while (!(UCA0IFG & UCRXIFG)){
    // keep waiting for the buffer to contain a char;
  }
  unsigned char c = UCA0RXBUF;
  
  return (c);
}

static void put_message(char *s)
{
  while (*s)
    putchar(*s++);
}


#define LINE_LENGTH 50         /* Change if you need */

#define In_BACKSP 0x08          /* ASCII  <--  */
#define In_DELETE 0x7F          /* ASCII <DEL> */
#define In_EOL '\r'             /* ASCII <CR> */
#define In_SKIP '\3'            /* ASCII control-C */
#define In_EOF '\x1A'           /* ASCII control-Z */

#define Out_DELETE "\x8 \x8"    /* VT100 backspace and clear */
#define Out_SKIP "^C\n"         /* ^C and new line */
#define Out_EOF "^Z"            /* ^Z and return EOF */

int (getchar)(void)
{
  static char io_buffer[LINE_LENGTH + 2];     /* Where to put chars */
  static int ptr;                             /* Pointer in buffer */
  char c;

  for (;;)
  {
    if (io_buffer[ptr])
      return (io_buffer[ptr++]);
    ptr = 0;
    for (;;)
    {
      if ((c = _low_level_get()) == In_EOF && !ptr)
      {
        put_message(Out_EOF);
        return EOF;
      }
      if (c == In_DELETE)
      {
        if (ptr)
        {
          ptr--;
          put_message(Out_DELETE);
        }
      }
      else if (c == In_SKIP)
      {
        put_message(Out_SKIP);
        ptr = LINE_LENGTH + 1;  /* Where there always is a zero... */
        break;
      }
      else if (c == In_EOL)
      {
        putchar(io_buffer[ptr++] = '\n');
        io_buffer[ptr] = 0;
        ptr = 0;
        break;
      }
      else if (ptr < LINE_LENGTH)
      {
        if (c >= ' ')
        {
          putchar(io_buffer[ptr++] = c);
        }
      }
      else
      {
        putchar('\7');
      }
    }
  }
}

_STD_END