Add virtual filesystem for FUSE supported platforms.

RomRepoMgr.Core/ForcedSeekStream.cs

@@ -0,0 +1,205 @@
+// /***************************************************************************
+// Aaru Data Preservation Suite
+// ----------------------------------------------------------------------------
+//
+// Filename       : ForcedSeekStream.cs
+// Author(s)      : Natalia Portillo <claunia@claunia.com>
+//
+// Component      : Filters.
+//
+// --[ Description ] ----------------------------------------------------------
+//
+//     Provides a seekable stream from a forward-readable stream.
+//
+// --[ 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 © 2011-2020 Natalia Portillo
+// ****************************************************************************/
+
+using System;
+using System.IO;
+
+namespace RomRepoMgr.Core
+{
+    /// <inheritdoc />
+    /// <summary>
+    ///     ForcedSeekStream allows to seek a forward-readable stream (like System.IO.Compression streams) by doing the
+    ///     slow and known trick of rewinding and forward reading until arriving the desired position.
+    /// </summary>
+    internal sealed class ForcedSeekStream<T> : Stream where T : Stream
+    {
+        const    int        BUFFER_LEN = 1048576;
+        readonly string     _backFile;
+        readonly FileStream _backStream;
+        readonly T          _baseStream;
+        long                _streamLength;
+
+        /// <inheritdoc />
+        /// <summary>Initializes a new instance of the <see cref="T:RomRepoMgr.Core.ForcedSeekStream`1" /> class.</summary>
+        /// <param name="length">The real (uncompressed) length of the stream.</param>
+        /// <param name="args">Parameters that are used to create the base stream.</param>
+        public ForcedSeekStream(long length, params object[] args)
+        {
+            _streamLength = length;
+            _baseStream   = (T)Activator.CreateInstance(typeof(T), args);
+            _backFile     = Path.GetTempFileName();
+            _backStream   = new FileStream(_backFile, FileMode.Open, FileAccess.ReadWrite, FileShare.None);
+
+            if(length == 0)
+                CalculateLength();
+        }
+
+        public override bool CanRead => _baseStream.CanRead;
+
+        public override bool CanSeek => true;
+
+        public override bool CanWrite => false;
+
+        public override long Length => _streamLength;
+
+        public override long Position
+        {
+            get => _backStream.Position;
+
+            set => SetPosition(value);
+        }
+
+        /// <summary>
+        ///     Calculates the real (uncompressed) length of the stream. It basically reads (decompresses) the whole stream to
+        ///     memory discarding its contents, so it should be used as a last resort.
+        /// </summary>
+        /// <returns>The length.</returns>
+        void CalculateLength()
+        {
+            int read;
+
+            do
+            {
+                byte[] buffer = new byte[BUFFER_LEN];
+                read = _baseStream.Read(buffer, 0, BUFFER_LEN);
+                _backStream.Write(buffer, 0, read);
+            } while(read == BUFFER_LEN);
+
+            _streamLength        = _backStream.Length;
+            _backStream.Position = 0;
+        }
+
+        void SetPosition(long position)
+        {
+            if(position == _backStream.Position)
+                return;
+
+            if(position < _backStream.Length)
+            {
+                _backStream.Position = position;
+
+                return;
+            }
+
+            _backStream.Position = _backStream.Length;
+            long   toPosition      = position - _backStream.Position;
+            int    fullBufferReads = (int)(toPosition / BUFFER_LEN);
+            int    restToRead      = (int)(toPosition % BUFFER_LEN);
+            byte[] buffer;
+
+            for(int i = 0; i < fullBufferReads; i++)
+            {
+                buffer = new byte[BUFFER_LEN];
+                _baseStream.Read(buffer, 0, BUFFER_LEN);
+                _backStream.Write(buffer, 0, BUFFER_LEN);
+            }
+
+            buffer = new byte[restToRead];
+            _baseStream.Read(buffer, 0, restToRead);
+            _backStream.Write(buffer, 0, restToRead);
+        }
+
+        public override void Flush()
+        {
+            _baseStream.Flush();
+            _backStream.Flush();
+        }
+
+        public override int Read(byte[] buffer, int offset, int count)
+        {
+            if(_backStream.Position + count <= _backStream.Length)
+                return _backStream.Read(buffer, offset, count);
+
+            SetPosition(_backStream.Position + count);
+            SetPosition(_backStream.Position - count);
+
+            return _backStream.Read(buffer, offset, count);
+        }
+
+        public override int ReadByte()
+        {
+            if(_backStream.Position + 1 <= _backStream.Length)
+                return _backStream.ReadByte();
+
+            SetPosition(_backStream.Position + 1);
+            SetPosition(_backStream.Position - 1);
+
+            return _backStream.ReadByte();
+        }
+
+        public override long Seek(long offset, SeekOrigin origin)
+        {
+            switch(origin)
+            {
+                case SeekOrigin.Begin:
+                    if(offset < 0)
+                        throw new IOException("Cannot seek before stream start.");
+
+                    SetPosition(offset);
+
+                    break;
+                case SeekOrigin.End:
+                    if(offset > 0)
+                        throw new IOException("Cannot seek after stream end.");
+
+                    if(_streamLength == 0)
+                        CalculateLength();
+
+                    SetPosition(_streamLength + offset);
+
+                    break;
+                default:
+                    SetPosition(_backStream.Position + offset);
+
+                    break;
+            }
+
+            return _backStream.Position;
+        }
+
+        public override void SetLength(long value) => throw new NotSupportedException();
+
+        public override void Write(byte[] buffer, int offset, int count) => throw new NotSupportedException();
+
+        public override void Close()
+        {
+            _backStream?.Close();
+            File.Delete(_backFile);
+        }
+
+        ~ForcedSeekStream()
+        {
+            _backStream?.Close();
+            File.Delete(_backFile);
+        }
+    }
+}

RomRepoMgr.Core/RomRepoMgr.Core.csproj

@@ -6,6 +6,7 @@
 
     <ItemGroup>
       <PackageReference Include="DotNetZip" Version="1.13.8" />
+      <PackageReference Include="Mono.Fuse.NETStandard" Version="1.0.0" />
       <PackageReference Include="SharpCompress" Version="0.26.0" />
       <PackageReference Include="System.Security.Principal.Windows" Version="4.7.0" />
     </ItemGroup>

RomRepoMgr.sln.DotSettings

@@ -0,0 +1,4 @@
+<wpf:ResourceDictionary xml:space="preserve" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:s="clr-namespace:System;assembly=mscorlib" xmlns:ss="urn:shemas-jetbrains-com:settings-storage-xaml" xmlns:wpf="http://schemas.microsoft.com/winfx/2006/xaml/presentation">
+	<s:Boolean x:Key="/Default/UserDictionary/Words/=romrepombgrfs/@EntryIndexedValue">True</s:Boolean>
+	<s:Boolean x:Key="/Default/UserDictionary/Words/=xattr/@EntryIndexedValue">True</s:Boolean>
+	<s:Boolean x:Key="/Default/UserDictionary/Words/=xattrs/@EntryIndexedValue">True</s:Boolean></wpf:ResourceDictionary>

RomRepoMgr/ViewModels/MainWindowViewModel.cs

@@ -35,6 +35,7 @@ using MessageBox.Avalonia;
 using MessageBox.Avalonia.Enums;
 using ReactiveUI;
 using RomRepoMgr.Core.EventArgs;
+using RomRepoMgr.Core.Filesystem;
 using RomRepoMgr.Core.Models;
 using RomRepoMgr.Views;
 
@@ -59,6 +60,7 @@ namespace RomRepoMgr.ViewModels
             EditRomSetCommand      = ReactiveCommand.Create(ExecuteEditRomSetCommand);
             ExportDatCommand       = ReactiveCommand.Create(ExecuteExportDatCommand);
             ExportRomsCommand      = ReactiveCommand.Create(ExecuteExportRomsCommand);
+            MountCommand           = ReactiveCommand.Create(ExecuteMountCommand);
             RomSets                = new ObservableCollection<RomSetModel>(romSets);
         }
 
@@ -91,6 +93,7 @@ namespace RomRepoMgr.ViewModels
         public ReactiveCommand<Unit, Unit> EditRomSetCommand      { get; }
         public ReactiveCommand<Unit, Unit> ExportDatCommand       { get; }
         public ReactiveCommand<Unit, Unit> ExportRomsCommand      { get; }
+        public ReactiveCommand<Unit, Unit> MountCommand           { get; }
 
         public RomSetModel SelectedRomSet
         {
@@ -282,5 +285,28 @@ namespace RomRepoMgr.ViewModels
             dialog.DataContext = viewModel;
             await dialog.ShowDialog(_view);
         }
+
+        async void ExecuteMountCommand()
+        {
+            // TODO: Detect if Windows or *NIX
+            // TODO: Detect if libraries are available
+
+            var dlgOpen = new OpenFolderDialog
+            {
+                Title = "Select mount point..."
+            };
+
+            string result = await dlgOpen.ShowAsync(_view);
+
+            if(result == null)
+                return;
+
+            var fs = new Fuse
+            {
+                MountPoint = result
+            };
+
+            fs.Start();
+        }
     }
 }

RomRepoMgr/Views/MainWindow.xaml

@@ -16,6 +16,9 @@
                 <Separator />
                 <MenuItem Header="E_xit" IsVisible="{Binding !NativeMenuSupported}" Command="{Binding ExitCommand}" />
             </MenuItem>
+            <MenuItem Header="File_system">
+                <MenuItem Header="_Mount" Command="{Binding MountCommand}" /> <Separator />
+            </MenuItem>
             <MenuItem Header="_ROMs">
                 <MenuItem Header="_Import folder" Command="{Binding ImportRomFolderCommand}" /> <Separator />
             </MenuItem>