Files
Aaru/Aaru.Images/IMD/Read.cs

247 lines
8.8 KiB
C#

// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename : Read.cs
// Author(s) : Natalia Portillo <claunia@claunia.com>
//
// Component : Disk image plugins.
//
// --[ Description ] ----------------------------------------------------------
//
// Reads Dunfield's IMD disk images.
//
// --[ License ] --------------------------------------------------------------
//
// This library is free software; you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation; either version 2.1 of the
// License, or (at your option) any later version.
//
// This library 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
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, see <http://www.gnu.org/licenses/>.
//
// ----------------------------------------------------------------------------
// Copyright © 2011-2025 Natalia Portillo
// ****************************************************************************/
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using Aaru.CommonTypes;
using Aaru.CommonTypes.Enums;
using Aaru.CommonTypes.Interfaces;
using Aaru.Helpers;
using Aaru.Logging;
namespace Aaru.Images;
public sealed partial class Imd
{
#region IMediaImage Members
/// <inheritdoc />
public ErrorNumber Open(IFilter imageFilter)
{
Stream stream = imageFilter.GetDataForkStream();
stream.Seek(0, SeekOrigin.Begin);
var cmt = new MemoryStream();
stream.Seek(0x1F, SeekOrigin.Begin);
for(uint i = 0; i < stream.Length; i++)
{
var b = (byte)stream.ReadByte();
if(b == 0x1A) break;
cmt.WriteByte(b);
}
_imageInfo.Comments = StringHandlers.CToString(cmt.ToArray());
_sectorsData = [];
byte currentCylinder = 0;
_imageInfo.Cylinders = 1;
_imageInfo.Heads = 1;
ulong currentLba = 0;
TransferRate mode = TransferRate.TwoHundred;
while(stream.Position + 5 < stream.Length)
{
mode = (TransferRate)stream.ReadByte();
var cylinder = (byte)stream.ReadByte();
var head = (byte)stream.ReadByte();
var spt = (byte)stream.ReadByte();
var n = (byte)stream.ReadByte();
var idmap = new byte[spt];
var cylmap = new byte[spt];
var headmap = new byte[spt];
var bps = new ushort[spt];
if(cylinder != currentCylinder)
{
currentCylinder = cylinder;
_imageInfo.Cylinders++;
}
if((head & 1) == 1) _imageInfo.Heads = 2;
stream.EnsureRead(idmap, 0, idmap.Length);
if((head & SECTOR_CYLINDER_MAP_MASK) == SECTOR_CYLINDER_MAP_MASK)
stream.EnsureRead(cylmap, 0, cylmap.Length);
if((head & SECTOR_HEAD_MAP_MASK) == SECTOR_HEAD_MAP_MASK) stream.EnsureRead(headmap, 0, headmap.Length);
if(n == 0xFF)
{
var bpsbytes = new byte[spt * 2];
stream.EnsureRead(bpsbytes, 0, bpsbytes.Length);
for(var i = 0; i < spt; i++) bps[i] = BitConverter.ToUInt16(bpsbytes, i * 2);
}
else
for(var i = 0; i < spt; i++)
bps[i] = (ushort)(128 << n);
if(spt > _imageInfo.SectorsPerTrack) _imageInfo.SectorsPerTrack = spt;
SortedDictionary<byte, byte[]> track = new();
for(var i = 0; i < spt; i++)
{
var type = (SectorType)stream.ReadByte();
var data = new byte[bps[i]];
// TODO; Handle disks with different bps in track 0
if(bps[i] > _imageInfo.SectorSize) _imageInfo.SectorSize = bps[i];
// TODO: Preserve sector status information
switch(type)
{
case SectorType.Unavailable:
if(!track.ContainsKey(idmap[i])) track.Add(idmap[i], data);
break;
case SectorType.Normal:
case SectorType.Deleted:
case SectorType.Error:
case SectorType.DeletedError:
stream.EnsureRead(data, 0, data.Length);
if(!track.ContainsKey(idmap[i])) track.Add(idmap[i], data);
_imageInfo.ImageSize += (ulong)data.Length;
break;
case SectorType.Compressed:
case SectorType.CompressedDeleted:
case SectorType.CompressedError:
case SectorType.CompressedDeletedError:
var filling = (byte)stream.ReadByte();
ArrayHelpers.ArrayFill(data, filling);
if(!track.ContainsKey(idmap[i])) track.Add(idmap[i], data);
break;
default:
AaruLogging.Error(string.Format(Localization.Invalid_sector_type_0, (byte)type));
return ErrorNumber.InvalidArgument;
}
}
foreach(KeyValuePair<byte, byte[]> kvp in track)
{
_sectorsData.Add(kvp.Value);
currentLba++;
}
}
_imageInfo.Application = "IMD";
// TODO: The header is the date of dump or the date of the application compilation?
_imageInfo.CreationTime = imageFilter.CreationTime;
_imageInfo.LastModificationTime = imageFilter.LastWriteTime;
_imageInfo.MediaTitle = Path.GetFileNameWithoutExtension(imageFilter.Filename);
_imageInfo.Comments = StringHandlers.CToString(cmt.ToArray());
_imageInfo.Sectors = currentLba;
_imageInfo.MediaType = MediaType.Unknown;
MediaEncoding mediaEncoding = MediaEncoding.MFM;
if(mode is TransferRate.TwoHundred or TransferRate.ThreeHundred or TransferRate.FiveHundred)
mediaEncoding = MediaEncoding.FM;
_imageInfo.MediaType = Geometry.GetMediaType(((ushort)_imageInfo.Cylinders, (byte)_imageInfo.Heads,
(ushort)_imageInfo.SectorsPerTrack, _imageInfo.SectorSize,
mediaEncoding, false));
switch(_imageInfo.MediaType)
{
case MediaType.NEC_525_HD when mode == TransferRate.FiveHundredMfm:
_imageInfo.MediaType = MediaType.NEC_35_HD_8;
break;
case MediaType.DOS_525_HD when mode == TransferRate.FiveHundredMfm:
_imageInfo.MediaType = MediaType.NEC_35_HD_15;
break;
case MediaType.RX50 when mode == TransferRate.FiveHundredMfm:
_imageInfo.MediaType = MediaType.ATARI_35_SS_DD;
break;
}
_imageInfo.MetadataMediaType = MetadataMediaType.BlockMedia;
AaruLogging.Verbose(Localization.IMD_image_contains_a_disk_of_type_0, _imageInfo.MediaType);
if(!string.IsNullOrEmpty(_imageInfo.Comments))
AaruLogging.Verbose(Localization.IMD_comments_0, _imageInfo.Comments);
return ErrorNumber.NoError;
}
/// <inheritdoc />
public ErrorNumber ReadSector(ulong sectorAddress, bool negative, out byte[] buffer, out SectorStatus sectorStatus)
{
sectorStatus = SectorStatus.Dumped;
return ReadSectors(sectorAddress, negative, 1, out buffer, out _);
}
/// <inheritdoc />
public ErrorNumber ReadSectors(ulong sectorAddress, bool negative, uint length, out byte[] buffer,
out SectorStatus[] sectorStatus)
{
buffer = null;
sectorStatus = null;
if(negative) return ErrorNumber.NotSupported;
if(sectorAddress > _imageInfo.Sectors - 1) return ErrorNumber.OutOfRange;
if(sectorAddress + length > _imageInfo.Sectors) return ErrorNumber.OutOfRange;
var ms = new MemoryStream();
sectorStatus = Enumerable.Repeat(SectorStatus.Dumped, (int)length).ToArray();
for(var i = 0; i < length; i++)
ms.Write(_sectorsData[(int)sectorAddress + i], 0, _sectorsData[(int)sectorAddress + i].Length);
buffer = ms.ToArray();
return ErrorNumber.NoError;
}
#endregion
}