Use error returning Open() in IFilter.

Aaru.Filters/AppleDouble.cs

@@ -36,6 +36,7 @@ using System.IO;
 using System.Linq;
 using System.Runtime.InteropServices;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Helpers;
 using Marshal = Aaru.Helpers.Marshal;
 
@@ -74,54 +75,50 @@ namespace Aaru.Filters
         {
             0x56, 0x41, 0x58, 0x20, 0x56, 0x4D, 0x53, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20
         };
-        string   _basePath;
-        DateTime _creationTime;
         Entry  _dataFork;
         Header _header;
         string _headerPath;
-        DateTime _lastWriteTime;
-        bool     _opened;
         Entry  _rsrcFork;
 
         /// <inheritdoc />
         public string Name => "AppleDouble";
         /// <inheritdoc />
-        public Guid Id => new Guid("1B2165EE-C9DF-4B21-BBBB-9E5892B2DF4D");
+        public Guid Id => new("1B2165EE-C9DF-4B21-BBBB-9E5892B2DF4D");
         /// <inheritdoc />
         public string Author => "Natalia Portillo";
 
         /// <inheritdoc />
-        public void Close() => _opened = false;
+        public void Close() {}
 
         /// <inheritdoc />
-        public string GetBasePath() => _basePath;
+        public string BasePath { get; private set; }
 
         /// <inheritdoc />
-        public DateTime GetCreationTime() => _creationTime;
+        public DateTime CreationTime { get; private set; }
 
         /// <inheritdoc />
-        public long GetDataForkLength() => _dataFork.length;
+        public long DataForkLength => _dataFork.length;
 
         /// <inheritdoc />
-        public Stream GetDataForkStream() => new FileStream(_basePath, FileMode.Open, FileAccess.Read);
+        public Stream GetDataForkStream() => new FileStream(BasePath, FileMode.Open, FileAccess.Read);
 
         /// <inheritdoc />
-        public string GetFilename() => Path.GetFileName(_basePath);
+        public string Filename => System.IO.Path.GetFileName(BasePath);
 
         /// <inheritdoc />
-        public DateTime GetLastWriteTime() => _lastWriteTime;
+        public DateTime LastWriteTime { get; private set; }
 
         /// <inheritdoc />
-        public long GetLength() => _dataFork.length + _rsrcFork.length;
+        public long Length => _dataFork.length + _rsrcFork.length;
 
         /// <inheritdoc />
-        public string GetParentFolder() => Path.GetDirectoryName(_basePath);
+        public string ParentFolder => System.IO.Path.GetDirectoryName(BasePath);
 
         /// <inheritdoc />
-        public string GetPath() => _basePath;
+        public string Path => BasePath;
 
         /// <inheritdoc />
-        public long GetResourceForkLength() => _rsrcFork.length;
+        public long ResourceForkLength => _rsrcFork.length;
 
         /// <inheritdoc />
         public Stream GetResourceForkStream()
@@ -134,7 +131,7 @@ namespace Aaru.Filters
         }
 
         /// <inheritdoc />
-        public bool HasResourceFork() => _rsrcFork.length > 0;
+        public bool HasResourceFork => _rsrcFork.length > 0;
 
         /// <inheritdoc />
         public bool Identify(byte[] buffer) => false;
@@ -145,9 +142,9 @@ namespace Aaru.Filters
         /// <inheritdoc />
         public bool Identify(string path)
         {
-            string filename      = Path.GetFileName(path);
+            string filename      = System.IO.Path.GetFileName(path);
-            string filenameNoExt = Path.GetFileNameWithoutExtension(path);
+            string filenameNoExt = System.IO.Path.GetFileNameWithoutExtension(path);
-            string parentFolder  = Path.GetDirectoryName(path);
+            string parentFolder  = System.IO.Path.GetDirectoryName(path);
 
             parentFolder ??= "";
 
@@ -156,28 +153,28 @@ namespace Aaru.Filters
                 return false;
 
             // Prepend data fork name with "R."
-            string proDosAppleDouble = Path.Combine(parentFolder, "R." + filename);
+            string proDosAppleDouble = System.IO.Path.Combine(parentFolder, "R." + filename);
 
             // Prepend data fork name with '%'
-            string unixAppleDouble = Path.Combine(parentFolder, "%" + filename);
+            string unixAppleDouble = System.IO.Path.Combine(parentFolder, "%" + filename);
 
             // Change file extension to ADF
-            string dosAppleDouble = Path.Combine(parentFolder, filenameNoExt + ".ADF");
+            string dosAppleDouble = System.IO.Path.Combine(parentFolder, filenameNoExt + ".ADF");
 
             // Change file extension to adf
-            string dosAppleDoubleLower = Path.Combine(parentFolder, filenameNoExt + ".adf");
+            string dosAppleDoubleLower = System.IO.Path.Combine(parentFolder, filenameNoExt + ".adf");
 
             // Store AppleDouble header file in ".AppleDouble" folder with same name
-            string netatalkAppleDouble = Path.Combine(parentFolder, ".AppleDouble", filename);
+            string netatalkAppleDouble = System.IO.Path.Combine(parentFolder, ".AppleDouble", filename);
 
             // Store AppleDouble header file in "resource.frk" folder with same name
-            string daveAppleDouble = Path.Combine(parentFolder, "resource.frk", filename);
+            string daveAppleDouble = System.IO.Path.Combine(parentFolder, "resource.frk", filename);
 
             // Prepend data fork name with "._"
-            string osxAppleDouble = Path.Combine(parentFolder, "._" + filename);
+            string osxAppleDouble = System.IO.Path.Combine(parentFolder, "._" + filename);
 
             // Adds ".rsrc" extension
-            string unArAppleDouble = Path.Combine(parentFolder, filename + ".rsrc");
+            string unArAppleDouble = System.IO.Path.Combine(parentFolder, filename + ".rsrc");
 
             // Check AppleDouble created by A/UX in ProDOS filesystem
             if(File.Exists(proDosAppleDouble))
@@ -322,53 +319,50 @@ namespace Aaru.Filters
             return _header.magic == MAGIC && (_header.version == VERSION || _header.version == VERSION2);
         }
 
-        /// <inheritdoc />
-        public bool IsOpened() => _opened;
-
         // Now way to have two files in a single byte array
         /// <inheritdoc />
-        public void Open(byte[] buffer) => throw new NotSupportedException();
+        public Errno Open(byte[] buffer) => Errno.NotSupported;
 
         // Now way to have two files in a single stream
         /// <inheritdoc />
-        public void Open(Stream stream) => throw new NotSupportedException();
+        public Errno Open(Stream stream) => Errno.NotSupported;
 
         /// <inheritdoc />
-        public void Open(string path)
+        public Errno Open(string path)
         {
-            string filename      = Path.GetFileName(path);
+            string filename      = System.IO.Path.GetFileName(path);
-            string filenameNoExt = Path.GetFileNameWithoutExtension(path);
+            string filenameNoExt = System.IO.Path.GetFileNameWithoutExtension(path);
-            string parentFolder  = Path.GetDirectoryName(path);
+            string parentFolder  = System.IO.Path.GetDirectoryName(path);
 
             parentFolder ??= "";
 
             if(filename is null ||
                filenameNoExt is null)
-                throw new ArgumentNullException(nameof(path));
+                return Errno.InvalidArgument;
 
             // Prepend data fork name with "R."
-            string proDosAppleDouble = Path.Combine(parentFolder, "R." + filename);
+            string proDosAppleDouble = System.IO.Path.Combine(parentFolder, "R." + filename);
 
             // Prepend data fork name with '%'
-            string unixAppleDouble = Path.Combine(parentFolder, "%" + filename);
+            string unixAppleDouble = System.IO.Path.Combine(parentFolder, "%" + filename);
 
             // Change file extension to ADF
-            string dosAppleDouble = Path.Combine(parentFolder, filenameNoExt + ".ADF");
+            string dosAppleDouble = System.IO.Path.Combine(parentFolder, filenameNoExt + ".ADF");
 
             // Change file extension to adf
-            string dosAppleDoubleLower = Path.Combine(parentFolder, filenameNoExt + ".adf");
+            string dosAppleDoubleLower = System.IO.Path.Combine(parentFolder, filenameNoExt + ".adf");
 
             // Store AppleDouble header file in ".AppleDouble" folder with same name
-            string netatalkAppleDouble = Path.Combine(parentFolder, ".AppleDouble", filename);
+            string netatalkAppleDouble = System.IO.Path.Combine(parentFolder, ".AppleDouble", filename);
 
             // Store AppleDouble header file in "resource.frk" folder with same name
-            string daveAppleDouble = Path.Combine(parentFolder, "resource.frk", filename);
+            string daveAppleDouble = System.IO.Path.Combine(parentFolder, "resource.frk", filename);
 
             // Prepend data fork name with "._"
-            string osxAppleDouble = Path.Combine(parentFolder, "._" + filename);
+            string osxAppleDouble = System.IO.Path.Combine(parentFolder, "._" + filename);
 
             // Adds ".rsrc" extension
-            string unArAppleDouble = Path.Combine(parentFolder, filename + ".rsrc");
+            string unArAppleDouble = System.IO.Path.Combine(parentFolder, filename + ".rsrc");
 
             // Check AppleDouble created by A/UX in ProDOS filesystem
             if(File.Exists(proDosAppleDouble))
@@ -514,6 +508,10 @@ namespace Aaru.Filters
                 }
             }
 
+            // TODO: More appropriate error
+            if(_headerPath is null)
+                return Errno.NotSupported;
+
             var fs = new FileStream(_headerPath, FileMode.Open, FileAccess.Read);
             fs.Seek(0, SeekOrigin.Begin);
 
@@ -530,8 +528,8 @@ namespace Aaru.Filters
                 entries[i] = Marshal.ByteArrayToStructureBigEndian<Entry>(entry);
             }
 
-            _creationTime  = DateTime.UtcNow;
+            CreationTime  = DateTime.UtcNow;
-            _lastWriteTime = _creationTime;
+            LastWriteTime = CreationTime;
 
             foreach(Entry entry in entries)
                 switch((EntryId)entry.id)
@@ -546,8 +544,8 @@ namespace Aaru.Filters
 
                         FileDates dates = Marshal.ByteArrayToStructureBigEndian<FileDates>(datesB);
 
-                        _creationTime  = DateHandlers.UnixUnsignedToDateTime(dates.creationDate);
+                        CreationTime  = DateHandlers.UnixUnsignedToDateTime(dates.creationDate);
-                        _lastWriteTime = DateHandlers.UnixUnsignedToDateTime(dates.modificationDate);
+                        LastWriteTime = DateHandlers.UnixUnsignedToDateTime(dates.modificationDate);
 
                         break;
                     case EntryId.FileInfo:
@@ -559,28 +557,28 @@ namespace Aaru.Filters
                         {
                             MacFileInfo macinfo = Marshal.ByteArrayToStructureBigEndian<MacFileInfo>(finfo);
 
-                            _creationTime  = DateHandlers.MacToDateTime(macinfo.creationDate);
+                            CreationTime  = DateHandlers.MacToDateTime(macinfo.creationDate);
-                            _lastWriteTime = DateHandlers.MacToDateTime(macinfo.modificationDate);
+                            LastWriteTime = DateHandlers.MacToDateTime(macinfo.modificationDate);
                         }
                         else if(_proDosHome.SequenceEqual(_header.homeFilesystem))
                         {
                             ProDOSFileInfo prodosinfo = Marshal.ByteArrayToStructureBigEndian<ProDOSFileInfo>(finfo);
 
-                            _creationTime  = DateHandlers.MacToDateTime(prodosinfo.creationDate);
+                            CreationTime  = DateHandlers.MacToDateTime(prodosinfo.creationDate);
-                            _lastWriteTime = DateHandlers.MacToDateTime(prodosinfo.modificationDate);
+                            LastWriteTime = DateHandlers.MacToDateTime(prodosinfo.modificationDate);
                         }
                         else if(_unixHome.SequenceEqual(_header.homeFilesystem))
                         {
                             UnixFileInfo unixinfo = Marshal.ByteArrayToStructureBigEndian<UnixFileInfo>(finfo);
 
-                            _creationTime  = DateHandlers.UnixUnsignedToDateTime(unixinfo.creationDate);
+                            CreationTime  = DateHandlers.UnixUnsignedToDateTime(unixinfo.creationDate);
-                            _lastWriteTime = DateHandlers.UnixUnsignedToDateTime(unixinfo.modificationDate);
+                            LastWriteTime = DateHandlers.UnixUnsignedToDateTime(unixinfo.modificationDate);
                         }
                         else if(_dosHome.SequenceEqual(_header.homeFilesystem))
                         {
                             DOSFileInfo dosinfo = Marshal.ByteArrayToStructureBigEndian<DOSFileInfo>(finfo);
 
-                            _lastWriteTime =
+                            LastWriteTime =
                                 DateHandlers.DosToDateTime(dosinfo.modificationDate, dosinfo.modificationTime);
                         }
 
@@ -604,8 +602,9 @@ namespace Aaru.Filters
             }
 
             fs.Close();
-            _opened   = true;
+            BasePath = path;
-            _basePath = path;
+
+            return Errno.NoError;
         }
 
         enum EntryId : uint

Aaru.Filters/AppleSingle.cs

@@ -36,6 +36,7 @@ using System.IO;
 using System.Linq;
 using System.Runtime.InteropServices;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Helpers;
 using Marshal = Aaru.Helpers.Marshal;
 
@@ -96,7 +97,6 @@ namespace Aaru.Filters
             _isBytes  = false;
             _isStream = false;
             _isPath   = false;
-            Opened    = false;
         }
 
         /// <inheritdoc />
@@ -217,10 +217,7 @@ namespace Aaru.Filters
         }
 
         /// <inheritdoc />
-        public bool Opened { get; private set; }
+        public Errno Open(byte[] buffer)
-
-        /// <inheritdoc />
-        public void Open(byte[] buffer)
         {
             var ms = new MemoryStream(buffer);
             ms.Seek(0, SeekOrigin.Begin);
@@ -301,13 +298,14 @@ namespace Aaru.Filters
                 }
 
             ms.Close();
-            Opened   = true;
             _isBytes = true;
             _bytes   = buffer;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(Stream stream)
+        public Errno Open(Stream stream)
         {
             stream.Seek(0, SeekOrigin.Begin);
 
@@ -387,13 +385,14 @@ namespace Aaru.Filters
                 }
 
             stream.Seek(0, SeekOrigin.Begin);
-            Opened    = true;
             _isStream = true;
             _stream   = stream;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(string path)
+        public Errno Open(string path)
         {
             var fs = new FileStream(path, FileMode.Open, FileAccess.Read);
             fs.Seek(0, SeekOrigin.Begin);
@@ -474,9 +473,10 @@ namespace Aaru.Filters
                 }
 
             fs.Close();
-            Opened   = true;
             _isPath  = true;
             BasePath = path;
+
+            return Errno.NoError;
         }
 
         enum AppleSingleEntryID : uint

Aaru.Filters/BZip2.cs

@@ -33,6 +33,7 @@
 using System;
 using System.IO;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using SharpCompress.Compressors;
 using SharpCompress.Compressors.BZip2;
 
@@ -58,7 +59,6 @@ namespace Aaru.Filters
             _dataStream?.Close();
             _dataStream = null;
             BasePath    = null;
-            Opened      = false;
         }
 
         /// <inheritdoc />
@@ -151,7 +151,7 @@ namespace Aaru.Filters
         }
 
         /// <inheritdoc />
-        public void Open(byte[] buffer)
+        public Errno Open(byte[] buffer)
         {
             _dataStream    = new MemoryStream(buffer);
             BasePath       = null;
@@ -159,11 +159,12 @@ namespace Aaru.Filters
             LastWriteTime  = CreationTime;
             _innerStream   = new ForcedSeekStream<BZip2Stream>(_dataStream, CompressionMode.Decompress, false);
             DataForkLength = _innerStream.Length;
-            Opened         = true;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(Stream stream)
+        public Errno Open(Stream stream)
         {
             _dataStream    = stream;
             BasePath       = null;
@@ -171,11 +172,12 @@ namespace Aaru.Filters
             LastWriteTime  = CreationTime;
             _innerStream   = new ForcedSeekStream<BZip2Stream>(_dataStream, CompressionMode.Decompress, false);
             DataForkLength = _innerStream.Length;
-            Opened         = true;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(string path)
+        public Errno Open(string path)
         {
             _dataStream = new FileStream(path, FileMode.Open, FileAccess.Read);
             BasePath    = System.IO.Path.GetFullPath(path);
@@ -185,7 +187,8 @@ namespace Aaru.Filters
             LastWriteTime  = fi.LastWriteTimeUtc;
             _innerStream   = new ForcedSeekStream<BZip2Stream>(_dataStream, CompressionMode.Decompress, false);
             DataForkLength = _innerStream.Length;
-            Opened         = true;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
@@ -218,8 +221,5 @@ namespace Aaru.Filters
 
         /// <inheritdoc />
         public string ParentFolder => System.IO.Path.GetDirectoryName(BasePath);
-
-        /// <inheritdoc />
-        public bool Opened { get; private set; }
     }
 }

Aaru.Filters/GZip.cs

@@ -34,6 +34,7 @@ using System;
 using System.IO;
 using System.IO.Compression;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Helpers;
 
 namespace Aaru.Filters
@@ -59,7 +60,6 @@ namespace Aaru.Filters
             _dataStream?.Close();
             _dataStream = null;
             BasePath    = null;
-            Opened      = false;
         }
 
         /// <inheritdoc />
@@ -109,7 +109,7 @@ namespace Aaru.Filters
         }
 
         /// <inheritdoc />
-        public void Open(byte[] buffer)
+        public Errno Open(byte[] buffer)
         {
             byte[] mtimeB = new byte[4];
             byte[] isizeB = new byte[4];
@@ -132,11 +132,11 @@ namespace Aaru.Filters
 
             _zStream = new ForcedSeekStream<GZipStream>(_decompressedSize, _dataStream, CompressionMode.Decompress);
 
-            Opened = true;
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(Stream stream)
+        public Errno Open(Stream stream)
         {
             byte[] mtimeB = new byte[4];
             byte[] isizeB = new byte[4];
@@ -159,11 +159,11 @@ namespace Aaru.Filters
 
             _zStream = new ForcedSeekStream<GZipStream>(_decompressedSize, _dataStream, CompressionMode.Decompress);
 
-            Opened = true;
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(string path)
+        public Errno Open(string path)
         {
             byte[] mtimeB = new byte[4];
             byte[] isizeB = new byte[4];
@@ -185,7 +185,8 @@ namespace Aaru.Filters
             CreationTime = fi.CreationTimeUtc;
             LastWriteTime = DateHandlers.UnixUnsignedToDateTime(mtime);
             _zStream = new ForcedSeekStream<GZipStream>(_decompressedSize, _dataStream, CompressionMode.Decompress);
-            Opened = true;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
@@ -218,8 +219,5 @@ namespace Aaru.Filters
 
         /// <inheritdoc />
         public string ParentFolder => System.IO.Path.GetDirectoryName(BasePath);
-
-        /// <inheritdoc />
-        public bool Opened { get; private set; }
     }
 }

Aaru.Filters/LZip.cs

@@ -33,6 +33,7 @@
 using System;
 using System.IO;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using SharpCompress.Compressors;
 using SharpCompress.Compressors.LZMA;
 
@@ -58,7 +59,6 @@ namespace Aaru.Filters
             _dataStream?.Close();
             _dataStream = null;
             BasePath    = null;
-            Opened      = false;
         }
 
         /// <inheritdoc />
@@ -111,7 +111,7 @@ namespace Aaru.Filters
         }
 
         /// <inheritdoc />
-        public void Open(byte[] buffer)
+        public Errno Open(byte[] buffer)
         {
             _dataStream    = new MemoryStream(buffer);
             BasePath       = null;
@@ -121,11 +121,11 @@ namespace Aaru.Filters
 
             _innerStream = new ForcedSeekStream<LZipStream>(DataForkLength, _dataStream, CompressionMode.Decompress);
 
-            Opened = true;
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(Stream stream)
+        public Errno Open(Stream stream)
         {
             _dataStream   = stream;
             BasePath      = null;
@@ -137,11 +137,12 @@ namespace Aaru.Filters
             DataForkLength = BitConverter.ToInt64(tmp, 0);
             _dataStream.Seek(0, SeekOrigin.Begin);
             _innerStream = new ForcedSeekStream<LZipStream>(DataForkLength, _dataStream, CompressionMode.Decompress);
-            Opened       = true;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(string path)
+        public Errno Open(string path)
         {
             _dataStream = new FileStream(path, FileMode.Open, FileAccess.Read);
             BasePath    = System.IO.Path.GetFullPath(path);
@@ -155,7 +156,8 @@ namespace Aaru.Filters
             DataForkLength = BitConverter.ToInt64(tmp, 0);
             _dataStream.Seek(0, SeekOrigin.Begin);
             _innerStream = new ForcedSeekStream<LZipStream>(DataForkLength, _dataStream, CompressionMode.Decompress);
-            Opened       = true;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
@@ -188,8 +190,5 @@ namespace Aaru.Filters
 
         /// <inheritdoc />
         public string ParentFolder => System.IO.Path.GetDirectoryName(BasePath);
-
-        /// <inheritdoc />
-        public bool Opened { get; private set; }
     }
 }

Aaru.Filters/MacBinary.cs

@@ -35,6 +35,7 @@ using System.IO;
 using System.Runtime.InteropServices;
 using System.Text;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Helpers;
 using Marshal = Aaru.Helpers.Marshal;
 
@@ -68,7 +69,6 @@ namespace Aaru.Filters
             _isBytes  = false;
             _isStream = false;
             _isPath   = false;
-            Opened    = false;
         }
 
         /// <inheritdoc />
@@ -198,10 +198,7 @@ namespace Aaru.Filters
         }
 
         /// <inheritdoc />
-        public bool Opened { get; private set; }
+        public Errno Open(byte[] buffer)
-
-        /// <inheritdoc />
-        public void Open(byte[] buffer)
         {
             var ms = new MemoryStream(buffer);
             ms.Seek(0, SeekOrigin.Begin);
@@ -229,13 +226,14 @@ namespace Aaru.Filters
             LastWriteTime = DateHandlers.MacToDateTime(_header.modificationTime);
 
             ms.Close();
-            Opened   = true;
             _isBytes = true;
             _bytes   = buffer;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(Stream stream)
+        public Errno Open(Stream stream)
         {
             stream.Seek(0, SeekOrigin.Begin);
 
@@ -262,13 +260,14 @@ namespace Aaru.Filters
             LastWriteTime = DateHandlers.MacToDateTime(_header.modificationTime);
 
             stream.Seek(0, SeekOrigin.Begin);
-            Opened    = true;
             _isStream = true;
             _stream   = stream;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(string path)
+        public Errno Open(string path)
         {
             var fs = new FileStream(path, FileMode.Open, FileAccess.Read);
             fs.Seek(0, SeekOrigin.Begin);
@@ -296,9 +295,10 @@ namespace Aaru.Filters
             LastWriteTime = DateHandlers.MacToDateTime(_header.modificationTime);
 
             fs.Close();
-            Opened   = true;
             _isPath  = true;
             BasePath = path;
+
+            return Errno.NoError;
         }
 
         [StructLayout(LayoutKind.Sequential, Pack = 1)]

Aaru.Filters/PCExchange.cs

@@ -38,6 +38,7 @@ using System.IO;
 using System.Runtime.InteropServices;
 using System.Text;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Helpers;
 using Marshal = System.Runtime.InteropServices.Marshal;
 
@@ -62,7 +63,7 @@ namespace Aaru.Filters
         public string Author => "Natalia Portillo";
 
         /// <inheritdoc />
-        public void Close() => Opened = false;
+        public void Close() {}
 
         /// <inheritdoc />
         public string BasePath { get; private set; }
@@ -170,16 +171,13 @@ namespace Aaru.Filters
         }
 
         /// <inheritdoc />
-        public bool Opened { get; private set; }
+        public Errno Open(byte[] buffer) => Errno.NotSupported;
 
         /// <inheritdoc />
-        public void Open(byte[] buffer) => throw new NotSupportedException();
+        public Errno Open(Stream stream) => Errno.NotSupported;
 
         /// <inheritdoc />
-        public void Open(Stream stream) => throw new NotSupportedException();
+        public Errno Open(string path)
-
-        /// <inheritdoc />
-        public void Open(string path)
         {
             string parentFolder = System.IO.Path.GetDirectoryName(path);
             string baseFilename = System.IO.Path.GetFileName(path);
@@ -239,9 +237,10 @@ namespace Aaru.Filters
             ResourceForkLength = new FileInfo(_rsrcPath ?? throw new InvalidOperationException()).Length;
 
             BasePath = path;
-            Opened   = true;
 
             finderDatStream.Close();
+
+            return Errno.NoError;
         }
 
         [StructLayout(LayoutKind.Sequential, Pack = 1)]

Aaru.Filters/XZ.cs

@@ -33,6 +33,7 @@
 using System;
 using System.IO;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using SharpCompress.Compressors.Xz;
 
 namespace Aaru.Filters
@@ -57,7 +58,6 @@ namespace Aaru.Filters
             _dataStream?.Close();
             _dataStream = null;
             BasePath    = null;
-            Opened      = false;
         }
 
         /// <inheritdoc />
@@ -123,7 +123,7 @@ namespace Aaru.Filters
         }
 
         /// <inheritdoc />
-        public void Open(byte[] buffer)
+        public Errno Open(byte[] buffer)
         {
             _dataStream   = new MemoryStream(buffer);
             BasePath      = null;
@@ -131,11 +131,12 @@ namespace Aaru.Filters
             LastWriteTime = CreationTime;
             GuessSize();
             _innerStream = new ForcedSeekStream<XZStream>(DataForkLength, _dataStream);
-            Opened       = true;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(Stream stream)
+        public Errno Open(Stream stream)
         {
             _dataStream   = stream;
             BasePath      = null;
@@ -143,11 +144,12 @@ namespace Aaru.Filters
             LastWriteTime = CreationTime;
             GuessSize();
             _innerStream = new ForcedSeekStream<XZStream>(DataForkLength, _dataStream);
-            Opened       = true;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(string path)
+        public Errno Open(string path)
         {
             _dataStream = new FileStream(path, FileMode.Open, FileAccess.Read);
             BasePath    = System.IO.Path.GetFullPath(path);
@@ -157,7 +159,8 @@ namespace Aaru.Filters
             LastWriteTime = fi.LastWriteTimeUtc;
             GuessSize();
             _innerStream = new ForcedSeekStream<XZStream>(DataForkLength, _dataStream);
-            Opened       = true;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
@@ -191,9 +194,6 @@ namespace Aaru.Filters
         /// <inheritdoc />
         public string ParentFolder => System.IO.Path.GetDirectoryName(BasePath);
 
-        /// <inheritdoc />
-        public bool Opened { get; private set; }
-
         void GuessSize()
         {
             DataForkLength = 0;

Aaru.Filters/ZZZNoFilter.cs

@@ -33,6 +33,7 @@
 using System;
 using System.IO;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 
 namespace Aaru.Filters
 {
@@ -55,7 +56,6 @@ namespace Aaru.Filters
             _dataStream?.Close();
             _dataStream = null;
             BasePath    = null;
-            Opened      = false;
         }
 
         /// <inheritdoc />
@@ -83,34 +83,37 @@ namespace Aaru.Filters
         public bool Identify(string path) => File.Exists(path);
 
         /// <inheritdoc />
-        public void Open(byte[] buffer)
+        public Errno Open(byte[] buffer)
         {
             _dataStream   = new MemoryStream(buffer);
             BasePath      = null;
             CreationTime  = DateTime.UtcNow;
             LastWriteTime = CreationTime;
-            Opened        = true;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(Stream stream)
+        public Errno Open(Stream stream)
         {
             _dataStream   = stream;
             BasePath      = null;
             CreationTime  = DateTime.UtcNow;
             LastWriteTime = CreationTime;
-            Opened        = true;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
-        public void Open(string path)
+        public Errno Open(string path)
         {
             _dataStream = new FileStream(path, FileMode.Open, FileAccess.Read);
             BasePath    = System.IO.Path.GetFullPath(path);
             var fi = new FileInfo(path);
             CreationTime  = fi.CreationTimeUtc;
             LastWriteTime = fi.LastWriteTimeUtc;
-            Opened        = true;
+
+            return Errno.NoError;
         }
 
         /// <inheritdoc />
@@ -133,8 +136,5 @@ namespace Aaru.Filters
 
         /// <inheritdoc />
         public string ParentFolder => System.IO.Path.GetDirectoryName(BasePath);
-
-        /// <inheritdoc />
-        public bool Opened { get; private set; }
     }
 }

Aaru.Images/KryoFlux/Read.cs

@@ -37,6 +37,7 @@ using System.IO;
 using System.Linq;
 using Aaru.CommonTypes.Enums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Console;
 using Aaru.Filters;
 using Aaru.Helpers;
@@ -126,9 +127,8 @@ namespace Aaru.DiscImages
                     }
 
                 var trackFilter = new ZZZNoFilter();
-                trackFilter.Open(trackfile);
 
-                if(!trackFilter.Opened)
+                if(trackFilter.Open(trackfile) != Errno.NoError)
                     throw new IOException("Could not open KryoFlux track file.");
 
                 _imageInfo.CreationTime         = DateTime.MaxValue;

Aaru.Images/ZZZRawImage/Read.cs

@@ -369,7 +369,7 @@ namespace Aaru.DiscImages
                     var     filters = new FiltersList();
                     IFilter filter  = filters.GetFilter(basename + sidecar.name);
 
-                    if(filter.Opened != true)
+                    if(filter is null)
                         continue;
 
                     AaruConsole.DebugWriteLine("ZZZRawImage Plugin", "Found media tag {0}", sidecar.tag);

Aaru.Tests/Filters/AppleDoubleDave.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Filters;
 using NUnit.Framework;
 
@@ -103,8 +104,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new AppleDouble();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(737280, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(286, filter.ResourceForkLength);

Aaru.Tests/Filters/AppleDoubleDos.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Filters;
 using NUnit.Framework;
 
@@ -101,8 +102,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new AppleDouble();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(737280, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(286, filter.ResourceForkLength);

Aaru.Tests/Filters/AppleDoubleNetatalk.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Filters;
 using NUnit.Framework;
 
@@ -103,8 +104,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new AppleDouble();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(737280, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(286, filter.ResourceForkLength);

Aaru.Tests/Filters/AppleDoubleOsX.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Filters;
 using NUnit.Framework;
 
@@ -101,8 +102,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new AppleDouble();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(737280, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(286, filter.ResourceForkLength);

Aaru.Tests/Filters/AppleDoubleProDos.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Filters;
 using NUnit.Framework;
 
@@ -101,8 +102,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new AppleDouble();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(737280, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(286, filter.ResourceForkLength);

Aaru.Tests/Filters/AppleDoubleUnAr.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Filters;
 using NUnit.Framework;
 
@@ -101,8 +102,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new AppleDouble();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(737280, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(286, filter.ResourceForkLength);

Aaru.Tests/Filters/AppleDoubleUnix.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Filters;
 using NUnit.Framework;
 
@@ -101,8 +102,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new AppleDouble();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(737280, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(286, filter.ResourceForkLength);

Aaru.Tests/Filters/AppleSingle.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using NUnit.Framework;
 
 namespace Aaru.Tests.Filters
@@ -92,8 +93,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new Aaru.Filters.AppleSingle();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(737280, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(286, filter.ResourceForkLength);

Aaru.Tests/Filters/BZip2.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using NUnit.Framework;
 
 namespace Aaru.Tests.Filters
@@ -81,8 +82,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new Aaru.Filters.BZip2();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(1048576, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(0, filter.ResourceForkLength);

Aaru.Tests/Filters/GZip.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using NUnit.Framework;
 
 namespace Aaru.Tests.Filters
@@ -81,8 +82,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new Aaru.Filters.GZip();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(1048576, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(0, filter.ResourceForkLength);

Aaru.Tests/Filters/LZip.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using NUnit.Framework;
 
 namespace Aaru.Tests.Filters
@@ -81,8 +82,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new Aaru.Filters.LZip();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(1048576, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(0, filter.ResourceForkLength);

Aaru.Tests/Filters/MacBinary1.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Filters;
 using NUnit.Framework;
 
@@ -93,8 +94,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new MacBinary();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(737280, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(286, filter.ResourceForkLength);

Aaru.Tests/Filters/MacBinary2.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Filters;
 using NUnit.Framework;
 
@@ -93,8 +94,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new MacBinary();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(737280, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(286, filter.ResourceForkLength);

Aaru.Tests/Filters/MacBinary3.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Filters;
 using NUnit.Framework;
 
@@ -93,8 +94,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new MacBinary();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(737280, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(286, filter.ResourceForkLength);

Aaru.Tests/Filters/PCExchange.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using NUnit.Framework;
 
 namespace Aaru.Tests.Filters
@@ -94,8 +95,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new Aaru.Filters.PcExchange();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(737280, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(546, filter.ResourceForkLength);

Aaru.Tests/Filters/XZ.cs

@@ -29,6 +29,7 @@
 using System.IO;
 using Aaru.Checksums;
 using Aaru.CommonTypes.Interfaces;
+using Aaru.CommonTypes.Structs;
 using Aaru.Filters;
 using NUnit.Framework;
 
@@ -82,8 +83,7 @@ namespace Aaru.Tests.Filters
         public void Test()
         {
             IFilter filter = new XZ();
-            filter.Open(_location);
+            Assert.AreEqual(Errno.NoError, filter.Open(_location));
-            Assert.AreEqual(true, filter.Opened);
             Assert.AreEqual(1048576, filter.DataForkLength);
             Assert.AreNotEqual(null, filter.GetDataForkStream());
             Assert.AreEqual(0, filter.ResourceForkLength);