mirror of
https://github.com/aaru-dps/Aaru.git
synced 2025-12-16 11:14:25 +00:00
90 lines
3.3 KiB
C#
90 lines
3.3 KiB
C#
// /***************************************************************************
|
|
// Aaru Data Preservation Suite
|
|
// ----------------------------------------------------------------------------
|
|
//
|
|
// Filename : Helpers.cs
|
|
// Author(s) : Michael Drüing <michael@drueing.de>
|
|
//
|
|
// Component : Disk image plugins.
|
|
//
|
|
// --[ Description ] ----------------------------------------------------------
|
|
//
|
|
// Contains helpers for DiskDupe DDI 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 © 2021-2025 Michael Drüing
|
|
// Copyright © 2011-2025 Natalia Portillo
|
|
// ****************************************************************************/
|
|
|
|
using System.IO;
|
|
using System.Linq;
|
|
using Aaru.Helpers;
|
|
using Aaru.Logging;
|
|
|
|
namespace Aaru.Images;
|
|
|
|
public sealed partial class DiskDupe
|
|
{
|
|
bool TryReadHeader(Stream stream, ref FileHeader fhdr, ref TrackInfo[] tmap, ref long[] toffsets)
|
|
{
|
|
var buffer = new byte[6];
|
|
FileHeader fHeader;
|
|
|
|
stream.Seek(0, SeekOrigin.Begin);
|
|
|
|
if(stream.Length < 256) return false;
|
|
|
|
// read and check signature
|
|
fHeader.signature = new byte[10];
|
|
stream.EnsureRead(fHeader.signature, 0, 10);
|
|
|
|
if(!fHeader.signature.SequenceEqual(_headerMagic)) return false;
|
|
|
|
// read and check disk type byte
|
|
fHeader.diskType = (byte)stream.ReadByte();
|
|
|
|
if(fHeader.diskType is < 1 or > 4) return false;
|
|
|
|
// seek to start of the trackmap
|
|
stream.Seek(TRACKMAP_OFFSET, SeekOrigin.Begin);
|
|
int numTracks = _diskTypes[fHeader.diskType].cyl * _diskTypes[fHeader.diskType].hd;
|
|
int trackLen = 512 * _diskTypes[fHeader.diskType].spt; // the length of a single track, in bytes
|
|
var trackMap = new TrackInfo[numTracks];
|
|
var trackOffsets = new long[numTracks];
|
|
|
|
AaruLogging.Debug(MODULE_NAME,
|
|
Localization.Identified_image_with_CHS_equals_0_1_2,
|
|
_diskTypes[fHeader.diskType].cyl,
|
|
_diskTypes[fHeader.diskType].hd,
|
|
_diskTypes[fHeader.diskType].spt);
|
|
|
|
// read the trackmap and store the track offsets
|
|
for(var i = 0; i < numTracks; i++)
|
|
{
|
|
stream.EnsureRead(buffer, 0, 6);
|
|
trackMap[i] = Marshal.ByteArrayToStructureLittleEndian<TrackInfo>(buffer);
|
|
trackOffsets[i] = trackLen * trackMap[i].trackNumber;
|
|
}
|
|
|
|
fhdr = fHeader;
|
|
tmap = trackMap;
|
|
toffsets = trackOffsets;
|
|
|
|
return true;
|
|
}
|
|
} |