DiskRam.cpp

Go to the documentation of this file.

/* ES40 emulator.
 * Copyright (C) 2007-2008 by the ES40 Emulator Project
 *
 * WWW    : http://sourceforge.net/projects/es40
 * E-mail : camiel@camicom.com
 * 
 * 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 2
 * 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 program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 * 
 * Although this is not required, the author would appreciate being notified of, 
 * and receiving any modifications you may make to the source code that might serve
 * the general public.
 */

#include "StdAfx.h"
#include "DiskRam.h"

CDiskRam::CDiskRam(CConfigurator*  cfg, CSystem*  sys, CDiskController*  c,
                   int idebus, int idedev) : CDisk(cfg, sys, c, idebus, idedev)
{
  byte_size = myCfg->get_num_value("size", false, 512 * 1024 * 1024);

  CHECK_ALLOCATION(ramdisk = malloc((size_t) byte_size));

  state.byte_pos = 0;

  sectors = 32;
  heads = 8;

  //calc_cylinders();
  determine_layout();

  model_number = myCfg->get_text_value("model_number", "ES40RAMDISK");

  printf("%s: Mounted RAMDISK, %"LL "d %d-byte blocks, %"LL "d/%d/%d.\n",
         devid_string, byte_size / state.block_size, state.block_size,
         cylinders, heads, sectors);
}

CDiskRam::~CDiskRam(void)
{
  if(ramdisk)
  {
    printf("%s: RAMDISK freed.\n", devid_string);
    free(ramdisk);
    ramdisk = 0;
  }
}

bool CDiskRam::seek_byte(off_t_large byte)
{
  if(byte >= byte_size)
  {
    FAILURE_1(InvalidArgument, "%s: Seek beyond end of file!\n", devid_string);
  }

  state.byte_pos = byte;
  return true;
}

size_t CDiskRam::read_bytes(void* dest, size_t bytes)
{
  if(state.byte_pos >= byte_size)
    return 0;

  while(state.byte_pos + bytes >= byte_size)
    bytes--;

  memcpy(dest, &(((char*) ramdisk)[state.byte_pos]), bytes);
  state.byte_pos += (unsigned long) bytes;
  return bytes;
}

size_t CDiskRam::write_bytes(void* src, size_t bytes)
{
  if(state.byte_pos >= byte_size)
    return 0;

  while(state.byte_pos + bytes >= byte_size)
    bytes--;

  memcpy(&(((char*) ramdisk)[state.byte_pos]), src, bytes);
  state.byte_pos += (unsigned long) bytes;
  return bytes;
}

Project space on SourceForge.net