diff --git a/Aaru.Filesystems/FATX/Analyze.cs b/Aaru.Filesystems/FATX/Analyze.cs new file mode 100644 index 000000000..b77d65797 --- /dev/null +++ b/Aaru.Filesystems/FATX/Analyze.cs @@ -0,0 +1,227 @@ +// /*************************************************************************** +// Aaru Data Preservation Suite +// ---------------------------------------------------------------------------- +// +// Filename : Analyze.cs +// Author(s) : Natalia Portillo +// +// 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 . +// +// ---------------------------------------------------------------------------- +// Copyright © 2011-2026 Natalia Portillo +// ****************************************************************************/ + +using System; +using System.Collections.Generic; +using System.Linq; +using Aaru.CommonTypes; +using Aaru.CommonTypes.Enums; +using Aaru.CommonTypes.Interfaces; +using Aaru.CommonTypes.Structs; + +namespace Aaru.Filesystems; + +public sealed partial class XboxFatPlugin +{ +#region IReadOnlyFilesystem Members + + /// + public ErrorNumber GetFilesWithAffectedSectors(IEnumerable<(ulong Start, ulong End)> sectorExtents, + out List files, + InitProgressHandler initProgress = null, + UpdateProgressHandler updateProgress = null, + PulseProgressHandler pulseProgress = null, + EndProgressHandler endProgress = null) + { + files = []; + + if(!_mounted) return ErrorNumber.AccessDenied; + if(sectorExtents is null) return ErrorNumber.InvalidArgument; + + List<(ulong Start, ulong End)> normalizedExtents = NormalizeAnalyzeExtents(sectorExtents); + + if(normalizedExtents.Count == 0) return ErrorNumber.NoError; + + try + { + initProgress?.Invoke(); + + return TraverseDirectoryForAffectedSectors("/", normalizedExtents, files, updateProgress, pulseProgress); + } + finally + { + endProgress?.Invoke(); + } + } + +#endregion + + ErrorNumber TraverseDirectoryForAffectedSectors(string path, List<(ulong Start, ulong End)> sectorExtents, + List files, UpdateProgressHandler updateProgress, + PulseProgressHandler pulseProgress) + { + pulseProgress?.Invoke(path); + + ErrorNumber errno = OpenDir(path, out IDirNode node); + + if(errno != ErrorNumber.NoError) return errno; + + if(node is not FatxDirNode dirNode) + { + CloseDir(node); + + return ErrorNumber.InvalidArgument; + } + + DirectoryEntry[] entries = dirNode.Entries + ?.OrderBy(static entry => + entry.filenameSize > 0 + ? entry.filename[0].ToString() + : string.Empty, + StringComparer.CurrentCultureIgnoreCase) + .ToArray() ?? []; + + CloseDir(node); + + long maximum = entries.Length > 0 ? entries.Length : 1; + + for(var i = 0; i < entries.Length; i++) + { + string entryName = entries[i].filenameSize > 0 + ? _encoding.GetString(entries[i].filename, 0, entries[i].filenameSize) + : string.Empty; + + if(string.IsNullOrWhiteSpace(entryName)) continue; + + string entryPath = path == "/" ? "/" + entryName : path + "/" + entryName; + + updateProgress?.Invoke(entryPath, i + 1, maximum); + + if(entries[i].attributes.HasFlag(Attributes.Directory)) + { + errno = TraverseDirectoryForAffectedSectors(entryPath, + sectorExtents, + files, + updateProgress, + pulseProgress); + + if(errno != ErrorNumber.NoError) return errno; + + continue; + } + + AddOverlappingFile(entryPath, entries[i], sectorExtents, files); + } + + return ErrorNumber.NoError; + } + + void AddOverlappingFile(string path, DirectoryEntry entry, IReadOnlyList<(ulong Start, ulong End)> sectorExtents, + List files) + { + if(entry.length == 0 || entry.firstCluster == 0) return; + + uint[] clusters = GetClusters(entry.firstCluster); + + if(clusters is null || clusters.Length == 0) return; + + List<(ulong Start, ulong End)> overlaps = FindOverlappingExtents(clusters, entry.length, sectorExtents); + + if(overlaps.Count == 0) return; + + files.Add(new FileSectorInfo + { + Path = path, + Inode = entry.firstCluster, + AffectedSectors = overlaps + }); + } + + List<(ulong Start, ulong End)> FindOverlappingExtents(uint[] clusters, uint logicalSize, + IReadOnlyList<(ulong Start, ulong End)> sectorExtents) + { + List<(ulong Start, ulong End)> overlaps = []; + ulong remainingBytes = logicalSize; + ulong sectorSize = _imagePlugin.Info.SectorSize; + + foreach(uint cluster in clusters) + { + if(remainingBytes == 0) break; + + if(cluster == 0) continue; + + ulong bytesInCluster = Math.Min(_bytesPerCluster, remainingBytes); + + if(bytesInCluster == 0) break; + + ulong startSector = _firstClusterSector + (cluster - 1) * _sectorsPerCluster; + ulong sectorCount = (bytesInCluster + sectorSize - 1) / sectorSize; + + if(sectorCount == 0) sectorCount = 1; + + AddExtentOverlaps(startSector, startSector + sectorCount - 1, sectorExtents, overlaps); + + remainingBytes -= bytesInCluster; + } + + return NormalizeAnalyzeExtents(overlaps); + } + + static void AddExtentOverlaps(ulong startSector, ulong endSector, + IReadOnlyList<(ulong Start, ulong End)> sectorExtents, + List<(ulong Start, ulong End)> overlaps) + { + foreach((ulong Start, ulong End) requestedExtent in sectorExtents) + { + if(requestedExtent.End < startSector || requestedExtent.Start > endSector) continue; + + overlaps.Add((Math.Max(startSector, requestedExtent.Start), Math.Min(endSector, requestedExtent.End))); + } + } + + static List<(ulong Start, ulong End)> NormalizeAnalyzeExtents(IEnumerable<(ulong Start, ulong End)> extents) + { + var orderedExtents = extents.Where(static extent => extent.End >= extent.Start) + .OrderBy(static extent => extent.Start) + .ThenBy(static extent => extent.End) + .ToList(); + + List<(ulong Start, ulong End)> normalizedExtents = []; + + if(orderedExtents.Count == 0) return normalizedExtents; + + (ulong Start, ulong End) currentExtent = orderedExtents[0]; + + for(var i = 1; i < orderedExtents.Count; i++) + { + if(orderedExtents[i].Start <= currentExtent.End + 1) + { + currentExtent.End = Math.Max(currentExtent.End, orderedExtents[i].End); + + continue; + } + + normalizedExtents.Add(currentExtent); + currentExtent = orderedExtents[i]; + } + + normalizedExtents.Add(currentExtent); + + return normalizedExtents; + } +} \ No newline at end of file