HD Image to parallel port

//////////////////////////////////////////////////////////////////////////////////
//    This file is HDIMAGE
//    Creation date is sometime in the 90's by Miguel Angel Rodriguez Jodar
//    (c)2020 Miguel Angel Rodriguez Jodar. ZXProjects
//
//    This program is free software: you can redistribute it and/or modify
//    it under the terms of the GNU General Public License as published by
//    the Free Software Foundation, either version 3 of the License, or
//    (at your option) any later version.
//
//    This program is distributed in the hope that it will be useful,
//    but WITHOUT ANY WARRANTY; without even the implied warranty of
//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//    GNU General Public License for more details.
//
//    You should have received a copy of the GNU General Public License
//    along with this core.  If not, see <https://www.gnu.org/licenses/>.
//
//    All copies of this file must keep this notice intact.
//
//////////////////////////////////////////////////////////////////////////////////

// Compile with Turbo C 2.0 for DOS

#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
#include <string.h>
#include <dos.h>
#include <bios.h>

int base;

#define DATOS (base)
#define ESTADO (DATOS+1)
#define CONTROL (DATOS+2)

int obtener_parametros_disco (int unidad, unsigned *cilindros, unsigned *cabezas, unsigned *sectores)
{
  int nc,nh,ns,estado;

  estado=nc=ns=nh=0;

  asm push bx
  asm push cx
  asm push dx
  asm push si
  asm push di
  asm mov ah,8
  asm mov dl,byte ptr unidad
  asm int 13h
  asm mov byte ptr estado,ah
  asm mov byte ptr ns,cl
  asm and cl,0c0h
  asm shr cl,6
  asm xchg cl,ch
  asm inc cx
  asm mov nc,cx
  asm inc dh
  asm mov byte ptr nh,dh
  asm pop di
  asm pop si
  asm pop dx
  asm pop cx
  asm pop bx

  ns&=0x3f;
  *cilindros=nc;
  *cabezas=nh;
  *sectores=ns;

  return estado;
}

void escribe_paralelo (char *buffer, int tam)
{
  int i;
  char dato;

  for (i=0;i<tam;i++)
  {
    dato=buffer[i];
    while ((inp(ESTADO) & 0x80)==0)
    {
      if (kbhit())
        if (getch()==27)
          exit(1);
    }

    outp (DATOS, dato);
    outp (CONTROL, 1);

    while (inp(ESTADO) & 0x80)
    {
      if (kbhit())
        if (getch()==27)
          exit(1);
    }

    outp (CONTROL, 0);
  }
}

void main (int argc, char *argv[])
{
  unsigned unidad, cilindros, cabezas, sectores;
  unsigned cylact, cabact, secact, estado;
  unsigned long total;
  int *dpuerto;
  char *buffer;

  dpuerto=MK_FP (0x40, 0x8);
  base=*dpuerto;

  unidad=atoi(argv[1]);
  estado=obtener_parametros_disco (unidad, &cilindros, &cabezas, &sectores);

  if (argc<5 && estado!=0)
  {
    printf ("Uso: HDIMAGE unidad cilindros cabezas sectores\n");
    exit(1);
  }

  if (argc>=5)
  {
    cilindros=atoi(argv[2]);
    cabezas=atoi(argv[3]);
    sectores=atoi(argv[4]);
  }

  buffer=malloc(sectores*512);

  printf ("Se ha encontrado un puerto paralelo en %04.4X\n", base);

  printf ("Se va a proceder a leer desde la unidad %02.2X, con geometr¡a: %4u cilindros, %4u cabezas, %4u sectores por pista\n",
           unidad, cilindros, cabezas, sectores);
  total=(unsigned long)cilindros*(unsigned long)cabezas*(unsigned long)sectores;
  printf ("Se transferiran %lu Mb.\n", total/2048);
  printf ("Continuar? (S/N)");
  if (getch()!='s')
    exit(1);

  printf ("\n\n");

  for (cylact=0;cylact<cilindros;cylact++)
  {
    for (cabact=0;cabact<cabezas;cabact++)
    {
      for (secact=1;secact<=sectores;secact++)
      {
        estado=biosdisk(2,unidad,cabact,cylact,secact,1,buffer);
        if (estado)
        {
          printf ("\n\nERROR!!! No se pudo leer el disco. (C=%d,H=%d,S=%d)\n",cylact,cabact,secact);
          exit(1);
        }
        escribe_paralelo (buffer,512);
        printf ("Realizado el %d %% de la operacion...  (%u:%u:%u)         \r", cylact*100/(cilindros-1), cylact, cabact, secact);
      }
    }
  }
  free(buffer);
}