Files
Aaru/Aaru.Filesystems/FATX/Super.cs
2025-08-14 15:51:32 +01:00

286 lines
11 KiB
C#

// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename : Super.cs
// Author(s) : Natalia Portillo <claunia@claunia.com>
//
// Component : FATX 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.Globalization;
using System.Runtime.InteropServices;
using System.Text;
using Aaru.CommonTypes.AaruMetadata;
using Aaru.CommonTypes.Enums;
using Aaru.CommonTypes.Interfaces;
using Aaru.Console;
using Aaru.Helpers;
using FileSystemInfo = Aaru.CommonTypes.Structs.FileSystemInfo;
using Marshal = Aaru.Helpers.Marshal;
using Partition = Aaru.CommonTypes.Partition;
namespace Aaru.Filesystems;
public sealed partial class XboxFatPlugin
{
#region IReadOnlyFilesystem Members
/// <inheritdoc />
public ErrorNumber Mount(IMediaImage imagePlugin, Partition partition, Encoding encoding,
Dictionary<string, string> options, string @namespace)
{
_encoding = Encoding.GetEncoding("iso-8859-15");
_littleEndian = true;
options ??= GetDefaultOptions();
if(options.TryGetValue("debug", out string debugString)) bool.TryParse(debugString, out _debug);
if(imagePlugin.Info.SectorSize < 512) return ErrorNumber.InvalidArgument;
AaruConsole.DebugWriteLine(MODULE_NAME, Localization.Reading_superblock);
ErrorNumber errno = imagePlugin.ReadSector(partition.Start, out byte[] sector);
if(errno != ErrorNumber.NoError) return errno;
_superblock = Marshal.ByteArrayToStructureLittleEndian<Superblock>(sector);
if(_superblock.magic == FATX_CIGAM)
{
_superblock = Marshal.ByteArrayToStructureBigEndian<Superblock>(sector);
_littleEndian = false;
}
if(_superblock.magic != FATX_MAGIC) return ErrorNumber.InvalidArgument;
AaruConsole.DebugWriteLine(MODULE_NAME,
_littleEndian
? Localization.Filesystem_is_little_endian
: Localization.Filesystem_is_big_endian);
int logicalSectorsPerPhysicalSectors = partition.Offset == 0 && _littleEndian ? 8 : 1;
AaruConsole.DebugWriteLine(MODULE_NAME,
"logicalSectorsPerPhysicalSectors = {0}",
logicalSectorsPerPhysicalSectors);
string volumeLabel = StringHandlers.CToString(_superblock.volumeLabel,
!_littleEndian ? Encoding.BigEndianUnicode : Encoding.Unicode,
true);
Metadata = new FileSystem
{
Type = Localization.FATX_filesystem,
ClusterSize = (uint)(_superblock.sectorsPerCluster *
logicalSectorsPerPhysicalSectors *
imagePlugin.Info.SectorSize),
VolumeName = volumeLabel,
VolumeSerial = $"{_superblock.id:X8}"
};
Metadata.Clusters = (partition.End - partition.Start + 1) * imagePlugin.Info.SectorSize / Metadata.ClusterSize;
_statfs = new FileSystemInfo
{
Blocks = Metadata.Clusters,
FilenameLength = MAX_FILENAME,
Files = 0, // Requires traversing all directories
FreeFiles = 0,
Id =
{
IsInt = true,
Serial32 = _superblock.magic
},
PluginId = Id,
Type = _littleEndian ? "Xbox FAT" : "Xbox 360 FAT",
FreeBlocks = 0 // Requires traversing the FAT
};
AaruConsole.DebugWriteLine(MODULE_NAME, "XmlFsType.ClusterSize: {0}", Metadata.ClusterSize);
AaruConsole.DebugWriteLine(MODULE_NAME, "XmlFsType.VolumeName: {0}", Metadata.VolumeName);
AaruConsole.DebugWriteLine(MODULE_NAME, "XmlFsType.VolumeSerial: {0}", Metadata.VolumeSerial);
AaruConsole.DebugWriteLine(MODULE_NAME, "stat.Blocks: {0}", _statfs.Blocks);
AaruConsole.DebugWriteLine(MODULE_NAME, "stat.FilenameLength: {0}", _statfs.FilenameLength);
AaruConsole.DebugWriteLine(MODULE_NAME, "stat.Id: {0}", _statfs.Id.Serial32);
AaruConsole.DebugWriteLine(MODULE_NAME, "stat.Type: {0}", _statfs.Type);
byte[] buffer;
_fatStartSector = FAT_START / imagePlugin.Info.SectorSize + partition.Start;
uint fatSize;
AaruConsole.DebugWriteLine(MODULE_NAME, "fatStartSector: {0}", _fatStartSector);
if(_statfs.Blocks > MAX_XFAT16_CLUSTERS)
{
AaruConsole.DebugWriteLine(MODULE_NAME, Localization.Reading_FAT32);
fatSize = (uint)((_statfs.Blocks + 1) * sizeof(uint) / imagePlugin.Info.SectorSize);
if((uint)((_statfs.Blocks + 1) * sizeof(uint) % imagePlugin.Info.SectorSize) > 0) fatSize++;
long fatClusters = fatSize * imagePlugin.Info.SectorSize / 4096;
if(fatSize * imagePlugin.Info.SectorSize % 4096 > 0) fatClusters++;
fatSize = (uint)(fatClusters * 4096 / imagePlugin.Info.SectorSize);
AaruConsole.DebugWriteLine(MODULE_NAME, Localization.FAT_is_0_sectors, fatSize);
errno = imagePlugin.ReadSectors(_fatStartSector, fatSize, out buffer);
if(errno != ErrorNumber.NoError) return errno;
AaruConsole.DebugWriteLine(MODULE_NAME, Localization.Casting_FAT);
_fat32 = MemoryMarshal.Cast<byte, uint>(buffer).ToArray();
if(!_littleEndian)
{
for(int i = 0; i < _fat32.Length; i++) _fat32[i] = Swapping.Swap(_fat32[i]);
}
AaruConsole.DebugWriteLine(MODULE_NAME, "fat32[0] == FATX32_ID = {0}", _fat32[0] == FATX32_ID);
if(_fat32[0] != FATX32_ID) return ErrorNumber.InvalidArgument;
}
else
{
AaruConsole.DebugWriteLine(MODULE_NAME, Localization.Reading_FAT16);
fatSize = (uint)((_statfs.Blocks + 1) * sizeof(ushort) / imagePlugin.Info.SectorSize);
if((uint)((_statfs.Blocks + 1) * sizeof(ushort) % imagePlugin.Info.SectorSize) > 0) fatSize++;
long fatClusters = fatSize * imagePlugin.Info.SectorSize / 4096;
if(fatSize * imagePlugin.Info.SectorSize % 4096 > 0) fatClusters++;
fatSize = (uint)(fatClusters * 4096 / imagePlugin.Info.SectorSize);
AaruConsole.DebugWriteLine(MODULE_NAME, Localization.FAT_is_0_sectors, fatSize);
errno = imagePlugin.ReadSectors(_fatStartSector, fatSize, out buffer);
if(errno != ErrorNumber.NoError) return errno;
AaruConsole.DebugWriteLine(MODULE_NAME, Localization.Casting_FAT);
_fat16 = MemoryMarshal.Cast<byte, ushort>(buffer).ToArray();
if(!_littleEndian)
{
for(int i = 0; i < _fat16.Length; i++) _fat16[i] = Swapping.Swap(_fat16[i]);
}
AaruConsole.DebugWriteLine(MODULE_NAME, "fat16[0] == FATX16_ID = {0}", _fat16[0] == FATX16_ID);
if(_fat16[0] != FATX16_ID) return ErrorNumber.InvalidArgument;
}
_sectorsPerCluster = (uint)(_superblock.sectorsPerCluster * logicalSectorsPerPhysicalSectors);
_imagePlugin = imagePlugin;
_firstClusterSector = _fatStartSector + fatSize;
_bytesPerCluster = _sectorsPerCluster * imagePlugin.Info.SectorSize;
AaruConsole.DebugWriteLine(MODULE_NAME, "sectorsPerCluster = {0}", _sectorsPerCluster);
AaruConsole.DebugWriteLine(MODULE_NAME, "bytesPerCluster = {0}", _bytesPerCluster);
AaruConsole.DebugWriteLine(MODULE_NAME, "firstClusterSector = {0}", _firstClusterSector);
uint[] rootDirectoryClusters = GetClusters(_superblock.rootDirectoryCluster);
if(rootDirectoryClusters is null) return ErrorNumber.InvalidArgument;
byte[] rootDirectoryBuffer = new byte[_bytesPerCluster * rootDirectoryClusters.Length];
AaruConsole.DebugWriteLine(MODULE_NAME, Localization.Reading_root_directory);
for(int i = 0; i < rootDirectoryClusters.Length; i++)
{
errno = imagePlugin.ReadSectors(_firstClusterSector + (rootDirectoryClusters[i] - 1) * _sectorsPerCluster,
_sectorsPerCluster,
out buffer);
if(errno != ErrorNumber.NoError) return errno;
Array.Copy(buffer, 0, rootDirectoryBuffer, i * _bytesPerCluster, _bytesPerCluster);
}
_rootDirectory = new Dictionary<string, DirectoryEntry>();
int pos = 0;
while(pos < rootDirectoryBuffer.Length)
{
DirectoryEntry entry = _littleEndian
? Marshal.ByteArrayToStructureLittleEndian<DirectoryEntry>(rootDirectoryBuffer,
pos,
Marshal.SizeOf<DirectoryEntry>())
: Marshal.ByteArrayToStructureBigEndian<DirectoryEntry>(rootDirectoryBuffer,
pos,
Marshal.SizeOf<DirectoryEntry>());
pos += Marshal.SizeOf<DirectoryEntry>();
if(entry.filenameSize is UNUSED_DIRENTRY or FINISHED_DIRENTRY) break;
if(entry.filenameSize is DELETED_DIRENTRY or > MAX_FILENAME) continue;
string filename = _encoding.GetString(entry.filename, 0, entry.filenameSize);
_rootDirectory.Add(filename, entry);
}
_cultureInfo = new CultureInfo("en-US", false);
_directoryCache = new Dictionary<string, Dictionary<string, DirectoryEntry>>();
_mounted = true;
return ErrorNumber.NoError;
}
/// <inheritdoc />
public ErrorNumber Unmount()
{
if(!_mounted) return ErrorNumber.AccessDenied;
_fat16 = null;
_fat32 = null;
_imagePlugin = null;
_mounted = false;
return ErrorNumber.NoError;
}
/// <inheritdoc />
public ErrorNumber StatFs(out FileSystemInfo stat)
{
stat = null;
if(!_mounted) return ErrorNumber.AccessDenied;
stat = _statfs.ShallowCopy();
return ErrorNumber.NoError;
}
#endregion
}