[AODOS] Add support for analyze command

Aaru.Filesystems/AODOS/Analyze.cs

@@ -0,0 +1,200 @@
+// /***************************************************************************
+// Aaru Data Preservation Suite
+// ----------------------------------------------------------------------------
+//
+// Filename       : Analyze.cs
+// Author(s)      : Natalia Portillo <claunia@claunia.com>
+//
+// Component      : AO-DOS file system 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 © 2011-2026 Natalia Portillo
+// ****************************************************************************/
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Aaru.CommonTypes;
+using Aaru.CommonTypes.Enums;
+using Aaru.CommonTypes.Structs;
+using Aaru.Helpers;
+
+namespace Aaru.Filesystems;
+
+// Information has been extracted looking at available disk images
+/// <inheritdoc />
+public sealed partial class AODOS
+{
+#region IReadOnlyFilesystem Members
+
+    /// <inheritdoc />
+    public ErrorNumber GetFilesWithAffectedSectors(IEnumerable<(ulong Start, ulong End)> sectorExtents,
+                                                   out List<FileSectorInfo>              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 || _directoryCache.Count == 0) return ErrorNumber.NoError;
+
+        try
+        {
+            initProgress?.Invoke();
+            pulseProgress?.Invoke("/");
+
+            Dictionary<byte, string> directoryNames = [];
+
+            foreach(DirectoryEntry entry in _directoryCache)
+            {
+                if(entry.directoryNumber == 0 || entry.directory != 0) continue;
+
+                string directoryName = StringHandlers.CToString(entry.filename, _encoding).Trim();
+
+                if(string.IsNullOrWhiteSpace(directoryName) || directoryNames.ContainsKey(entry.directoryNumber))
+                    continue;
+
+                directoryNames.Add(entry.directoryNumber, directoryName);
+            }
+
+            List<(string Path, DirectoryEntry Entry)> orderedEntries = [];
+
+            foreach(DirectoryEntry entry in _directoryCache)
+            {
+                if(entry.directoryNumber > 0) continue;
+
+                string fileName = StringHandlers.CToString(entry.filename, _encoding).Trim();
+
+                if(string.IsNullOrWhiteSpace(fileName)) continue;
+
+                if(entry.directory == 0)
+                    orderedEntries.Add(("/" + fileName, entry));
+                else if(directoryNames.TryGetValue(entry.directory, out string directoryName))
+                    orderedEntries.Add(("/" + directoryName + "/" + fileName, entry));
+            }
+
+            orderedEntries = orderedEntries.OrderBy(static entry => entry.Path, StringComparer.CurrentCultureIgnoreCase)
+                                           .ToList();
+
+            long maximum = orderedEntries.Count > 0 ? orderedEntries.Count : 1;
+
+            for(var i = 0; i < orderedEntries.Count; i++)
+            {
+                updateProgress?.Invoke(orderedEntries[i].Path, i + 1, maximum);
+                AddOverlappingFile(orderedEntries[i].Path, orderedEntries[i].Entry, normalizedExtents, files);
+            }
+
+            return ErrorNumber.NoError;
+        }
+        finally
+        {
+            endProgress?.Invoke();
+        }
+    }
+
+#endregion
+
+    void AddOverlappingFile(string path, in DirectoryEntry entry, IReadOnlyList<(ulong Start, ulong End)> sectorExtents,
+                            List<FileSectorInfo> files)
+    {
+        if(entry.directoryNumber > 0 || entry.length == 0 || entry.blocks == 0) return;
+
+        List<(ulong Start, ulong End)> overlaps = FindOverlappingExtents(entry, sectorExtents);
+
+        if(overlaps.Count == 0) return;
+
+        files.Add(new FileSectorInfo
+        {
+            Path            = path,
+            Inode           = entry.blockNumber,
+            AffectedSectors = overlaps
+        });
+    }
+
+    List<(ulong Start, ulong End)> FindOverlappingExtents(in DirectoryEntry                       entry,
+                                                          IReadOnlyList<(ulong Start, ulong End)> sectorExtents)
+    {
+        List<(ulong Start, ulong End)> overlaps = [];
+
+        ulong sectorCount = entry.blocks;
+
+        if(entry.length > 0)
+        {
+            ulong logicalSectors = ((ulong)entry.length + SECTOR_SIZE - 1) / SECTOR_SIZE;
+
+            if(logicalSectors > 0 && logicalSectors < sectorCount) sectorCount = logicalSectors;
+        }
+
+        if(sectorCount == 0) return overlaps;
+
+        ulong startSector = _partition.Start + entry.blockNumber;
+
+        AddExtentOverlaps(startSector, startSector + sectorCount - 1, sectorExtents, overlaps);
+
+        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;
+    }
+}