Files
Aaru/Aaru.Filesystems/AppleDOS/File.cs

303 lines
10 KiB
C#

// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename : File.cs
// Author(s) : Natalia Portillo <claunia@claunia.com>
//
// Component : Apple DOS filesystem plugin.
//
// --[ 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.Enums;
using Aaru.CommonTypes.Interfaces;
using Aaru.CommonTypes.Structs;
using Aaru.Helpers;
using FileAttributes = Aaru.CommonTypes.Structs.FileAttributes;
namespace Aaru.Filesystems;
public sealed partial class AppleDOS
{
ErrorNumber CacheFile(string path)
{
string[] pathElements = path.Split(['/'], StringSplitOptions.RemoveEmptyEntries);
if(pathElements.Length != 1) return ErrorNumber.NotSupported;
string filename = pathElements[0].ToUpperInvariant();
if(filename.Length > 30) return ErrorNumber.NameTooLong;
if(!_catalogCache.TryGetValue(filename, out ushort ts)) return ErrorNumber.NoSuchFile;
var lba = (ulong)(((ts & 0xFF00) >> 8) * _sectorsPerTrack + (ts & 0xFF));
var fileMs = new MemoryStream();
var tsListMs = new MemoryStream();
ushort expectedBlock = 0;
while(lba != 0)
{
_usedSectors++;
ErrorNumber errno = _device.ReadSector(lba, false, out byte[] tsSectorB, out _);
if(errno != ErrorNumber.NoError) return errno;
if(_debug) tsListMs.Write(tsSectorB, 0, tsSectorB.Length);
// Read the track/sector list sector
TrackSectorList tsSector = Marshal.ByteArrayToStructureLittleEndian<TrackSectorList>(tsSectorB);
if(tsSector.sectorOffset > expectedBlock)
{
var hole = new byte[(tsSector.sectorOffset - expectedBlock) * _vtoc.bytesPerSector];
fileMs.Write(hole, 0, hole.Length);
expectedBlock = tsSector.sectorOffset;
}
foreach(TrackSectorListEntry entry in tsSector.entries)
{
_track1UsedByFiles |= entry.track == 1;
_track2UsedByFiles |= entry.track == 2;
_usedSectors++;
var blockLba = (ulong)(entry.track * _sectorsPerTrack + entry.sector);
if(blockLba == 0) break;
errno = _device.ReadSector(blockLba, false, out byte[] fileBlock, out _);
if(errno != ErrorNumber.NoError) return errno;
fileMs.Write(fileBlock, 0, fileBlock.Length);
expectedBlock++;
}
lba = (ulong)(tsSector.nextListTrack * _sectorsPerTrack + tsSector.nextListSector);
}
if(_fileCache.ContainsKey(filename)) _fileCache.Remove(filename);
if(_extentCache.ContainsKey(filename)) _extentCache.Remove(filename);
if(_fileSizeCache.ContainsKey(filename)) _fileSizeCache.Remove(filename);
_fileCache.Add(filename, fileMs.ToArray());
_extentCache.Add(filename, tsListMs.ToArray());
_fileSizeCache.Add(filename, (int)fileMs.Length);
return ErrorNumber.NoError;
}
ErrorNumber CacheAllFiles()
{
_fileCache = new Dictionary<string, byte[]>();
_extentCache = new Dictionary<string, byte[]>();
foreach(ErrorNumber error in _catalogCache.Keys.Select(CacheFile)
.Where(static error => error != ErrorNumber.NoError))
return error;
uint tracksOnBoot = 1;
if(!_track1UsedByFiles) tracksOnBoot++;
if(!_track2UsedByFiles) tracksOnBoot++;
ErrorNumber errno =
_device.ReadSectors(0, false, (uint)(tracksOnBoot * _sectorsPerTrack), out _bootBlocks, out _);
if(errno != ErrorNumber.NoError) return errno;
_usedSectors += (uint)(_bootBlocks.Length / _vtoc.bytesPerSector);
return ErrorNumber.NoError;
}
#region IReadOnlyFilesystem Members
/// <inheritdoc />
public ErrorNumber GetAttributes(string path, out FileAttributes attributes)
{
attributes = new FileAttributes();
if(!_mounted) return ErrorNumber.AccessDenied;
string[] pathElements = path.Split(['/'], StringSplitOptions.RemoveEmptyEntries);
if(pathElements.Length != 1) return ErrorNumber.NotSupported;
string filename = pathElements[0].ToUpperInvariant();
if(!_fileCache.ContainsKey(filename)) return ErrorNumber.NoSuchFile;
attributes = FileAttributes.Extents;
attributes |= FileAttributes.File;
if(_lockedFiles.Contains(filename)) attributes |= FileAttributes.ReadOnly;
if(_debug &&
(string.Compare(path, "$", StringComparison.InvariantCulture) == 0 ||
string.Compare(path, "$Boot", StringComparison.InvariantCulture) == 0 ||
string.Compare(path, "$Vtoc", StringComparison.InvariantCulture) == 0))
attributes |= FileAttributes.System;
return ErrorNumber.NoError;
}
public ErrorNumber OpenFile(string path, out IFileNode node)
{
node = null;
if(!_mounted) return ErrorNumber.AccessDenied;
string[] pathElements = path.Split(['/'], StringSplitOptions.RemoveEmptyEntries);
if(pathElements.Length != 1) return ErrorNumber.NotSupported;
byte[] file;
string filename = pathElements[0].ToUpperInvariant();
if(filename.Length > 30) return ErrorNumber.NameTooLong;
if(_debug &&
(string.Compare(path, "$", StringComparison.InvariantCulture) == 0 ||
string.Compare(path, "$Boot", StringComparison.InvariantCulture) == 0 ||
string.Compare(path, "$Vtoc", StringComparison.InvariantCulture) == 0))
{
if(string.Compare(path, "$", StringComparison.InvariantCulture) == 0)
file = _catalogBlocks;
else if(string.Compare(path, "$Vtoc", StringComparison.InvariantCulture) == 0)
file = _vtocBlocks;
else
file = _bootBlocks;
}
else
{
if(!_fileCache.TryGetValue(filename, out file))
{
ErrorNumber error = CacheFile(filename);
if(error != ErrorNumber.NoError) return error;
if(!_fileCache.TryGetValue(filename, out file)) return ErrorNumber.InvalidArgument;
}
}
node = new AppleDosFileNode
{
Path = path,
Length = file.Length,
Offset = 0,
Cache = file
};
return ErrorNumber.NoError;
}
/// <inheritdoc />
public ErrorNumber CloseFile(IFileNode node)
{
if(!_mounted) return ErrorNumber.AccessDenied;
if(node is not AppleDosFileNode mynode) return ErrorNumber.InvalidArgument;
mynode.Cache = null;
return ErrorNumber.NoError;
}
/// <inheritdoc />
public ErrorNumber ReadFile(IFileNode node, long length, byte[] buffer, out long read)
{
read = 0;
if(!_mounted) return ErrorNumber.AccessDenied;
if(buffer is null || buffer.Length < length) return ErrorNumber.InvalidArgument;
if(node is not AppleDosFileNode mynode) return ErrorNumber.InvalidArgument;
read = length;
if(length + mynode.Offset >= mynode.Length) read = mynode.Length - mynode.Offset;
Array.Copy(mynode.Cache, mynode.Offset, buffer, 0, read);
mynode.Offset += read;
return ErrorNumber.NoError;
}
/// <inheritdoc />
public ErrorNumber Stat(string path, out FileEntryInfo stat)
{
stat = null;
if(!_mounted) return ErrorNumber.AccessDenied;
string[] pathElements = path.Split(['/'], StringSplitOptions.RemoveEmptyEntries);
if(pathElements.Length != 1) return ErrorNumber.NotSupported;
string filename = pathElements[0].ToUpperInvariant();
if(filename.Length > 30) return ErrorNumber.NameTooLong;
if(!_fileCache.ContainsKey(filename)) return ErrorNumber.NoSuchFile;
stat = new FileEntryInfo();
_fileSizeCache.TryGetValue(filename, out int fileSize);
GetAttributes(path, out FileAttributes attrs);
if(_debug &&
(string.Compare(path, "$", StringComparison.InvariantCulture) == 0 ||
string.Compare(path, "$Boot", StringComparison.InvariantCulture) == 0 ||
string.Compare(path, "$Vtoc", StringComparison.InvariantCulture) == 0))
{
if(string.Compare(path, "$", StringComparison.InvariantCulture) == 0)
stat.Length = _catalogBlocks.Length;
else if(string.Compare(path, "$Boot", StringComparison.InvariantCulture) == 0)
stat.Length = _bootBlocks.Length;
else if(string.Compare(path, "$Vtoc", StringComparison.InvariantCulture) == 0)
stat.Length = _vtocBlocks.Length;
stat.Blocks = stat.Length / _vtoc.bytesPerSector;
}
else
{
stat.Length = fileSize;
stat.Blocks = stat.Length / _vtoc.bytesPerSector;
}
stat.Attributes = attrs;
stat.BlockSize = _vtoc.bytesPerSector;
stat.Links = 1;
return ErrorNumber.NoError;
}
#endregion
}