Implement ReadDir() in Xbox FAT plugin.

DiscImageChef.Filesystems/FATX/Dir.cs

@@ -32,7 +32,9 @@
 
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using DiscImageChef.CommonTypes.Structs;
+using DiscImageChef.Helpers;
 
 namespace DiscImageChef.Filesystems.FATX
 {
@@ -43,7 +45,102 @@ namespace DiscImageChef.Filesystems.FATX
             contents = null;
             if(!mounted) return Errno.AccessDenied;
 
-            throw new NotImplementedException();
+            if(string.IsNullOrWhiteSpace(path) || path == "/")
+            {
+                contents = rootDirectory.Keys.ToList();
+                return Errno.NoError;
+            }
+
+            string cutPath = path.StartsWith("/") ? path.Substring(0).ToLower(cultureInfo) : path.ToLower(cultureInfo);
+
+            if(directoryCache.TryGetValue(cutPath, out Dictionary<string, DirectoryEntry> currentDirectory))
+            {
+                contents = currentDirectory.Keys.ToList();
+                return Errno.NoError;
+            }
+
+            string[] pieces = cutPath.Split('/');
+
+            KeyValuePair<string, DirectoryEntry> entry =
+                rootDirectory.FirstOrDefault(t => t.Key.ToLower(cultureInfo) == pieces[0]);
+
+            if(string.IsNullOrEmpty(entry.Key)) return Errno.NoSuchFile;
+
+            if(!entry.Value.attributes.HasFlag(Attributes.Directory)) return Errno.NotDirectory;
+
+            string currentPath = pieces[0];
+
+            currentDirectory = rootDirectory;
+
+            for(int p = 0; p < pieces.Length; p++)
+            {
+                entry = currentDirectory.FirstOrDefault(t => t.Key.ToLower(cultureInfo) == pieces[p]);
+
+                if(string.IsNullOrEmpty(entry.Key)) return Errno.NoSuchFile;
+
+                if(!entry.Value.attributes.HasFlag(Attributes.Directory)) return Errno.NotDirectory;
+
+                currentPath = p == 0 ? pieces[0] : $"{currentPath}/{pieces[p]}";
+                uint currentCluster = entry.Value.firstCluster;
+
+                if(directoryCache.TryGetValue(currentPath, out currentDirectory))
+                {
+                    if(p == pieces.Length - 1) break;
+
+                    entry = currentDirectory.FirstOrDefault(t => t.Key.ToLower(cultureInfo) == pieces[p]);
+
+                    if(string.IsNullOrEmpty(entry.Key)) return Errno.NoSuchFile;
+
+                    if(!entry.Value.attributes.HasFlag(Attributes.Directory)) return Errno.NotDirectory;
+
+                    continue;
+                }
+
+                uint[] clusters = GetClusters(currentCluster);
+
+                if(clusters is null) return Errno.InvalidArgument;
+
+                byte[] directoryBuffer = new byte[bytesPerCluster * clusters.Length];
+
+                for(int i = 0; i < clusters.Length; i++)
+                {
+                    byte[] buffer = imagePlugin.ReadSectors(firstClusterSector + (clusters[i] - 1) * sectorsPerCluster,
+                                                            sectorsPerCluster);
+                    Array.Copy(buffer, 0, directoryBuffer, i * bytesPerCluster, bytesPerCluster);
+                }
+
+                currentDirectory = new Dictionary<string, DirectoryEntry>();
+
+                int pos = 0;
+                while(pos < directoryBuffer.Length)
+                {
+                    DirectoryEntry dirent = littleEndian
+                                                ? Marshal
+                                                   .ByteArrayToStructureLittleEndian<DirectoryEntry
+                                                    >(directoryBuffer, pos, Marshal.SizeOf<DirectoryEntry>())
+                                                : Marshal.ByteArrayToStructureBigEndian<DirectoryEntry>(directoryBuffer,
+                                                                                                        pos,
+                                                                                                        Marshal
+                                                                                                           .SizeOf<
+                                                                                                                DirectoryEntry
+                                                                                                            >());
+
+                    pos += Marshal.SizeOf<DirectoryEntry>();
+
+                    if(dirent.filenameSize == UNUSED_DIRENTRY || dirent.filenameSize == FINISHED_DIRENTRY) break;
+
+                    if(dirent.filenameSize == DELETED_DIRENTRY || dirent.filenameSize > MAX_FILENAME) continue;
+
+                    string filename = Encoding.GetString(dirent.filename, 0, dirent.filenameSize);
+
+                    currentDirectory.Add(filename, dirent);
+                }
+
+                directoryCache.Add(currentPath, currentDirectory);
+            }
+
+            contents = currentDirectory?.Keys.ToList();
+            return Errno.NoError;
         }
     }
 }

DiscImageChef.Filesystems/FATX/FATX.cs

@@ -32,6 +32,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.Text;
 using DiscImageChef.CommonTypes;
 using DiscImageChef.CommonTypes.Interfaces;
@@ -42,18 +43,20 @@ namespace DiscImageChef.Filesystems.FATX
 {
     public partial class XboxFatPlugin : IReadOnlyFilesystem
     {
-        uint                               bytesPerCluster;
+        uint                                                   bytesPerCluster;
-        ushort[]                           fat16;
+        CultureInfo                                            cultureInfo;
-        uint[]                             fat32;
+        Dictionary<string, Dictionary<string, DirectoryEntry>> directoryCache;
-        ulong                              fatStartSector;
+        ushort[]                                               fat16;
-        ulong                              firstClusterSector;
+        uint[]                                                 fat32;
-        IMediaImage                        imagePlugin;
+        ulong                                                  fatStartSector;
-        bool                               littleEndian;
+        ulong                                                  firstClusterSector;
-        bool                               mounted;
+        IMediaImage                                            imagePlugin;
-        Partition                          partition;
+        bool                                                   littleEndian;
-        Dictionary<string, DirectoryEntry> rootDirectory;
+        bool                                                   mounted;
-        uint                               sectorsPerCluster;
+        Partition                                              partition;
-        FileSystemInfo                     stat;
+        Dictionary<string, DirectoryEntry>                     rootDirectory;
+        uint                                                   sectorsPerCluster;
+        FileSystemInfo                                         stat;
 
         Superblock            superblock;
         public FileSystemType XmlFsType { get; private set; }

DiscImageChef.Filesystems/FATX/Super.cs

@@ -32,6 +32,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.Runtime.InteropServices;
 using System.Text;
 using DiscImageChef.CommonTypes;
@@ -207,6 +208,9 @@ namespace DiscImageChef.Filesystems.FATX
                 rootDirectory.Add(filename, entry);
             }
 
+            cultureInfo    = new CultureInfo("en-US", false);
+            directoryCache = new Dictionary<string, Dictionary<string, DirectoryEntry>>();
+
             return Errno.NoError;
         }