Added Lisa filesystem code.

DiscImageChef.Filesystems/LisaFS/Dir.cs

@@ -37,6 +37,7 @@
 // //$Id$
 using System;
 using System.Collections.Generic;
+using DiscImageChef.ImagePlugins;
 
 namespace DiscImageChef.Filesystems.LisaFS
 {
@@ -50,7 +51,127 @@ namespace DiscImageChef.Filesystems.LisaFS
 
         public override Errno ReadDir(string path, ref List<string> contents)
         {
-            return Errno.NotImplemented;
+            Int16 fileId;
+            bool isDir;
+            Errno error = LookupFileId(path, out fileId, out isDir);
+            if(error != Errno.NoError)
+                return error;
+
+            if(!isDir)
+                return Errno.NotDirectory;
+
+            List<CatalogEntry> catalog;
+            ReadCatalog(fileId, out catalog);
+
+            foreach(CatalogEntry entry in catalog)
+                contents.Add(StringHandlers.CToString(entry.filename).Replace('/',':'));
+
+            if(debug && fileId == FILEID_DIRECTORY)
+            {
+                contents.Add("$MDDF");
+                contents.Add("$Boot");
+                contents.Add("$Loader");
+                contents.Add("$Bitmap");
+                contents.Add("$S-Record");
+                contents.Add("$");
+            }
+
+            contents.Sort();
+            return Errno.NoError;
+        }
+
+        Errno ReadCatalog(Int16 fileId, out List<CatalogEntry> catalog)
+        {
+            catalog = null;
+
+            if(!mounted)
+                return Errno.AccessDenied;
+
+            if(fileId < 4)
+                return Errno.InvalidArgument;
+
+            if(catalogCache.TryGetValue(fileId, out catalog))
+                return Errno.NoError;
+
+            int count = 0;
+
+            // Catalogs don't have extents files so we need to traverse all disk searching pieces (tend to be non fragmented and non expandable)
+            for(ulong i = 0; i < device.GetSectors(); i++)
+            {
+                byte[] tag = device.ReadSectorTag((ulong)i, SectorTagType.AppleSectorTag);
+                UInt16 id = BigEndianBitConverter.ToUInt16(tag, 0x04);
+
+                if(id == fileId)
+                    count++;
+
+                // Extents file found, it's not a catalog
+                if(id == -fileId)
+                    return Errno.NotDirectory;
+            }
+
+            if(count == 0)
+                return Errno.NoSuchFile;
+
+            byte[] buf = new byte[count * device.GetSectorSize()];
+
+            // This can be enhanced to follow linked tags. However on some disks a linked tag cuts a file, better not let it do with a catalog
+            for(ulong i = 0; i < device.GetSectors(); i++)
+            {
+                byte[] tag = device.ReadSectorTag((ulong)i, SectorTagType.AppleSectorTag);
+                UInt16 id = BigEndianBitConverter.ToUInt16(tag, 0x04);
+
+                if(id == fileId)
+                {
+                    UInt16 pos = BigEndianBitConverter.ToUInt16(tag, 0x06);
+                    byte[] sector = device.ReadSector(i);
+                    Array.Copy(sector, 0, buf, sector.Length * pos, sector.Length);
+                }
+            }
+
+            int offset = 0;
+
+            catalog = new List<CatalogEntry>();
+
+            while((offset + 64) <= buf.Length)
+            {
+                if(buf[offset + 0x24] == 0x08)
+                    offset += 78;
+                else if(buf[offset + 0x24] == 0x7C)
+                    offset += 50;
+                else if(buf[offset + 0x24] == 0xFF)
+                    break;
+                else if(buf[offset + 0x24] == 0x03 && buf[offset] == 0x24)
+                {
+                    CatalogEntry entry = new CatalogEntry();
+                    entry.marker = buf[offset];
+                    entry.zero = BigEndianBitConverter.ToUInt16(buf, offset + 0x01);
+                    entry.filename = new byte[E_NAME];
+                    Array.Copy(buf, offset + 0x03, entry.filename, 0, E_NAME);
+                    entry.padding = buf[offset + 0x23];
+                    entry.fileType = buf[offset + 0x24];
+                    entry.unknown = buf[offset + 0x25];
+                    entry.fileID = BigEndianBitConverter.ToInt16(buf, offset + 0x26);
+                    entry.dtc = BigEndianBitConverter.ToUInt32(buf, offset + 0x28);
+                    entry.dtm = BigEndianBitConverter.ToUInt32(buf, offset + 0x2C);
+                    entry.wasted = BigEndianBitConverter.ToInt32(buf, offset + 0x30);
+                    entry.length = BigEndianBitConverter.ToInt32(buf, offset + 0x34);
+                    entry.tail = new byte[8];
+                    Array.Copy(buf, offset + 0x38, entry.tail, 0, 8);
+                    catalog.Add(entry);
+
+                    if(fileSizeCache.ContainsKey(entry.fileID))
+                        fileSizeCache.Remove(entry.fileID);
+
+                    fileSizeCache.Add(entry.fileID, entry.length);
+
+                    offset += 64;
+                }
+                else
+                    break;
+            }
+
+            catalogCache.Add(fileId, catalog);
+            return Errno.NoError;
         }
     }
 }