/***************************************************************************
 *		  Copyright (C) 1994  Charles P. Peterson                  *
 *	     4007 Enchanted Sun, San Antonio, Texas 78244-1254             *
 *              Email: Charles_P_Peterson@fcircus.sat.tx.us                *
 *                                                                         *
 *		  This is free software with NO WARRANTY.                  *
 *	      See gfft.c, or run program itself, for details.              *
 *		      Support is available for a fee.                      *
 ***************************************************************************
 *
 * Program:     gfft--General FFT analysis
 * File:        prompt.c
 * Purpose:     prompt for and receive GFFT command string
 * Author:      Charles Peterson (CPP)
 * History:     29-May-1993 CPP; Created.
 * Comments:
 *              (1) Just to be nice, I'm considering EOF as an acceptable
 *              way to terminate gfft.  If it is preceded by a command on
 *              the same line, that is allowed to complete first.
 *              However, if DEBUG is defined, a message will be displayed
 *              on the detection of EOF.  (I seem to get EOF's for some
 *              reason when debugging.  Don't understand it yet.)
 *
 *              (2) Currently commands are quite limited in length
 *              inherently, so a limited buffer is quite OK.  Sure,
 *              it takes a few static bytes, but who's perfect?  If
 *              ever commands are allowed to get much larger I'll make it
 *              dynamic, but now that seems like overdoing it in view of
 *              how difficult C makes dealing with dynamic strings.
 *
 *              (3) However, I'm not going to let an excessively long
 *              command overwrite any other program data.  That's why
 *              this function is a little more tedious than it might
 *              be if I used 'gets' or 'scanf'.
 */

#include <stdio.h>
#include <dos/dosasl.h>  /* _OSERR */
#include <error.h>       /* errno */

#include "gfft.h"

void prompt_command (void)
{
    static int iclosed = FALSE;
    int icharacter = 0;
    int i;

    if (iclosed)
    {
	gabort (EXIT_SUCCESS);
    }
    printf ("%s",PROMPT);

    for (i=0; i < COMMAND_BUFFER_SIZE-1; i++)
    {
	icharacter = getc (stdin);
	if (icharacter == EOF)
	{

#ifdef _DEBUG
	    fprintf (stderr,"\nerrno = %d; _OSERR = %d\n", errno, _OSERR);
#endif

	    if (i <= 0)     /* error or EOF; shouldn't usually happen */
	    {
		gabort (EXIT_SUCCESS);
	    }
	    else            /* Command termined by EOF; exit on next call */
	    {
		iclosed = TRUE;
		Command[i] = '\0';
		break;
	    }
	}
	else if (icharacter == '\n')
	{
	    Command[i] = '\0';
	    break;
	}
	else
	{
	    Command[i] = (char) icharacter;
	}
    }
}