Files
Aaru/Aaru.Images/Apple2MG/Identify.cs

83 lines
2.7 KiB
C#

// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename : Identify.cs
// Author(s) : Natalia Portillo <claunia@claunia.com>
//
// Component : Disk image plugins.
//
// --[ Description ] ----------------------------------------------------------
//
// Identifies XGS emulator 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 © 2011-2023 Natalia Portillo
// ****************************************************************************/
using System.IO;
using Aaru.CommonTypes.Interfaces;
using Aaru.Helpers;
namespace Aaru.Images;
public sealed partial class Apple2Mg
{
#region IWritableImage Members
/// <inheritdoc />
public bool Identify(IFilter imageFilter)
{
Stream stream = imageFilter.GetDataForkStream();
stream.Seek(0, SeekOrigin.Begin);
if(stream.Length < 65)
return false;
var header = new byte[64];
stream.EnsureRead(header, 0, 64);
Header hdr = Marshal.SpanToStructureLittleEndian<Header>(header);
if(hdr.Magic != MAGIC)
return false;
if(hdr.DataOffset > stream.Length)
return false;
// There seems to be incorrect endian in some images on the wild
if(hdr.DataSize == 0x00800C00)
hdr.DataSize = 0x000C8000;
if(hdr.DataOffset + hdr.DataSize > stream.Length)
return false;
if(hdr.CommentOffset > stream.Length)
return false;
if(hdr.CommentOffset + hdr.CommentSize > stream.Length)
return false;
if(hdr.CreatorSpecificOffset > stream.Length)
return false;
return hdr.CreatorSpecificOffset + hdr.CreatorSpecificSize <= stream.Length;
}
#endregion
}