Aaru/Aaru.Filesystems/AppleDOS/Super.cs

// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename       : Super.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Apple DOS filesystem plugin.
//
// --[ Description ] ----------------------------------------------------------
//
//     Handles mounting and umounting the Apple DOS filesystem.
//
// --[ 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 © 2011-2021 Natalia Portillo
// ****************************************************************************/

using System.Collections.Generic;
using Aaru.CommonTypes;
using Aaru.CommonTypes.Enums;
using Aaru.CommonTypes.Interfaces;
using Aaru.CommonTypes.Structs;
using Aaru.Console;
using Aaru.Helpers;
using Claunia.Encoding;
using Schemas;
using Encoding = System.Text.Encoding;

namespace Aaru.Filesystems
{
    public sealed partial class AppleDOS
    {
        /// <inheritdoc />
        public ErrorNumber Mount(IMediaImage imagePlugin, Partition partition, Encoding encoding,
                                 Dictionary<string, string> options, string @namespace)
        {
            _device  = imagePlugin;
            _start   = partition.Start;
            Encoding = encoding ?? new Apple2();

            if(_device.Info.Sectors != 455 &&
               _device.Info.Sectors != 560)
            {
                AaruConsole.DebugWriteLine("Apple DOS plugin", "Incorrect device size.");

                return ErrorNumber.InOutError;
            }

            if(_start > 0)
            {
                AaruConsole.DebugWriteLine("Apple DOS plugin", "Partitions are not supported.");

                return ErrorNumber.InOutError;
            }

            if(_device.Info.SectorSize != 256)
            {
                AaruConsole.DebugWriteLine("Apple DOS plugin", "Incorrect sector size.");

                return ErrorNumber.InOutError;
            }

            _sectorsPerTrack = _device.Info.Sectors == 455 ? 13 : 16;

            // Read the VTOC
            ErrorNumber error = _device.ReadSector((ulong)(17 * _sectorsPerTrack), out _vtocBlocks);

            if(error != ErrorNumber.NoError)
                return error;

            _vtoc = Marshal.ByteArrayToStructureLittleEndian<Vtoc>(_vtocBlocks);

            _track1UsedByFiles = false;
            _track2UsedByFiles = false;
            _usedSectors       = 1;

            error = ReadCatalog();

            if(error != ErrorNumber.NoError)
            {
                AaruConsole.DebugWriteLine("Apple DOS plugin", "Unable to read catalog.");

                return error;
            }

            error = CacheAllFiles();

            if(error != ErrorNumber.NoError)
            {
                AaruConsole.DebugWriteLine("Apple DOS plugin", "Unable cache all files.");

                return error;
            }

            // Create XML metadata for mounted filesystem
            XmlFsType = new FileSystemType
            {
                Bootable              = true,
                Clusters              = _device.Info.Sectors,
                ClusterSize           = _vtoc.bytesPerSector,
                Files                 = (ulong)_catalogCache.Count,
                FilesSpecified        = true,
                FreeClustersSpecified = true,
                Type                  = "Apple DOS"
            };

            XmlFsType.FreeClusters = XmlFsType.Clusters - _usedSectors;

            options ??= GetDefaultOptions();

            if(options.TryGetValue("debug", out string debugString))
                bool.TryParse(debugString, out _debug);

            _mounted = true;

            return ErrorNumber.NoError;
        }

        /// <inheritdoc />
        public ErrorNumber Unmount()
        {
            _mounted       = false;
            _extentCache   = null;
            _fileCache     = null;
            _catalogCache  = null;
            _fileSizeCache = null;

            return ErrorNumber.NoError;
        }

        /// <inheritdoc />
        public ErrorNumber StatFs(out FileSystemInfo stat)
        {
            stat = new FileSystemInfo
            {
                Blocks         = _device.Info.Sectors,
                FilenameLength = 30,
                Files          = (ulong)_catalogCache.Count,
                PluginId       = Id,
                Type           = "Apple DOS"
            };

            stat.FreeFiles  = _totalFileEntries - stat.Files;
            stat.FreeBlocks = stat.Blocks       - _usedSectors;

            return ErrorNumber.NoError;
        }
    }
}