adtools/clib2

/*
 * $Id: debug_kgetnum1.c,v 1.3 2006-01-08 12:04:22 obarthel Exp $
 *
 * :ts=4
 *
 * Portable ISO 'C' (1994) runtime library for the Amiga computer
 * Copyright (c) 2002-2015 by Olaf Barthel <obarthel (at) gmx.net>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Neither the name of Olaf Barthel nor the names of contributors
 *     may be used to endorse or promote products derived from this
 *     software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "debug_headers.h"

/****************************************************************************/

LONG
kgetnum(VOID)
{
    LONG sum = 0;
    LONG result;
    BOOL is_negative = FALSE;
    LONG position = 0;
    LONG c;

    while(TRUE)
    {
        c = kgetc();

        if(c == '-')
        {
            if(position == 0)
            {
                is_negative = TRUE;

                kputc(c);

                position++;
            }
        }
        else if (c == '\b')
        {
            if(position > 0)
            {
                position--;
                if(position == 0)
                {
                    is_negative = FALSE;

                    sum = 0;
                }
                else
                {
                    sum = sum / 10;
                }

                kputc(c);
                kputc(' ');
                kputc(c);
            }
        }
        else if (c == '\r')
        {
            kputc('\n');
            break;
        }
        else if ('0' <= c && c <= '9')
        {
            LONG new_sum;

            new_sum = sum * 10 + (c - '0');
            if(new_sum >= sum)
            {
                sum = new_sum;

                kputc(c);

                position++;
            }
        }
    }

    if(is_negative)
        result = (-sum);
    else
        result = sum;

    return(result);
}