Aaru/DiscImageChef.Filesystems/SFS.cs

// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : SFS.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : SmartFileSystem plugin.
//
// --[ Description ] ----------------------------------------------------------
//
//     Identifies the SmartFileSystem and shows information.
//
// --[ 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 © 2011-2018 Natalia Portillo
// ****************************************************************************/

using System;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using System.Text;
using DiscImageChef.CommonTypes;
using DiscImageChef.DiscImages;
using Schemas;

namespace DiscImageChef.Filesystems
{
    public class SFS : IFilesystem
    {
        /// <summary>Identifier for SFS v1</summary>
        const uint SFS_MAGIC = 0x53465300;
        /// <summary>Identifier for SFS v2</summary>
        const uint SFS2_MAGIC = 0x53465302;
        FileSystemType xmlFsType;
        public virtual FileSystemType XmlFsType => xmlFsType;

        Encoding currentEncoding;
        public virtual Encoding Encoding => currentEncoding;
        public virtual string Name => "SmartFileSystem";
        public virtual Guid Id => new Guid("26550C19-3671-4A2D-BC2F-F20CEB7F48DC");

        public virtual bool Identify(IMediaImage imagePlugin, Partition partition)
        {
            if(partition.Start >= partition.End) return false;

            BigEndianBitConverter.IsLittleEndian = BitConverter.IsLittleEndian;

            byte[] sector = imagePlugin.ReadSector(partition.Start);

            uint magic = BigEndianBitConverter.ToUInt32(sector, 0x00);

            return magic == SFS_MAGIC || magic == SFS2_MAGIC;
        }

        public virtual void GetInformation(IMediaImage imagePlugin, Partition partition, out string information, Encoding encoding)
        {
            currentEncoding = encoding ?? Encoding.GetEncoding("iso-8859-1");
            byte[] rootBlockSector = imagePlugin.ReadSector(partition.Start);
            RootBlock rootBlock = BigEndianMarshal.ByteArrayToStructureBigEndian<RootBlock>(rootBlockSector);

            StringBuilder sbInformation = new StringBuilder();

            sbInformation.AppendLine("SmartFileSystem");

            sbInformation.AppendFormat("Volume version {0}", rootBlock.version).AppendLine();
            sbInformation.AppendFormat("Volume starts on device byte {0} and ends on byte {1}", rootBlock.firstbyte,
                                       rootBlock.lastbyte).AppendLine();
            sbInformation
                .AppendFormat("Volume has {0} blocks of {1} bytes each", rootBlock.totalblocks, rootBlock.blocksize)
                .AppendLine();
            sbInformation.AppendFormat("Volume created on {0}",
                                       DateHandlers.UnixUnsignedToDateTime(rootBlock.datecreated).AddYears(8))
                         .AppendLine();
            sbInformation.AppendFormat("Bitmap starts in block {0}", rootBlock.bitmapbase).AppendLine();
            sbInformation.AppendFormat("Admin space container starts in block {0}", rootBlock.adminspacecontainer)
                         .AppendLine();
            sbInformation.AppendFormat("Root object container starts in block {0}", rootBlock.rootobjectcontainer)
                         .AppendLine();
            sbInformation.AppendFormat("Root node of the extent B-tree resides in block {0}", rootBlock.extentbnoderoot)
                         .AppendLine();
            sbInformation.AppendFormat("Root node of the object B-tree resides in block {0}", rootBlock.objectnoderoot)
                         .AppendLine();
            if(rootBlock.bits.HasFlag(SFSFlags.CaseSensitive)) sbInformation.AppendLine("Volume is case sensitive");
            if(rootBlock.bits.HasFlag(SFSFlags.RecyledFolder))
                sbInformation.AppendLine("Volume moves deleted files to a recycled folder");
            information = sbInformation.ToString();

            xmlFsType = new FileSystemType
            {
                CreationDate = DateHandlers.UnixUnsignedToDateTime(rootBlock.datecreated).AddYears(8),
                CreationDateSpecified = true,
                Clusters = rootBlock.totalblocks,
                ClusterSize = (int)rootBlock.blocksize,
                Type = "SmartFileSystem"
            };
        }

        public virtual Errno Mount(IMediaImage imagePlugin, Partition partition, Encoding encoding, bool debug)
        {
            return Errno.NotImplemented;
        }

        public virtual Errno Unmount()
        {
            return Errno.NotImplemented;
        }

        public virtual Errno MapBlock(string path, long fileBlock, ref long deviceBlock)
        {
            return Errno.NotImplemented;
        }

        public virtual Errno GetAttributes(string path, ref FileAttributes attributes)
        {
            return Errno.NotImplemented;
        }

        public virtual Errno ListXAttr(string path, ref List<string> xattrs)
        {
            return Errno.NotImplemented;
        }

        public virtual Errno GetXattr(string path, string xattr, ref byte[] buf)
        {
            return Errno.NotImplemented;
        }

        public virtual Errno Read(string path, long offset, long size, ref byte[] buf)
        {
            return Errno.NotImplemented;
        }

        public virtual Errno ReadDir(string path, ref List<string> contents)
        {
            return Errno.NotImplemented;
        }

        public virtual Errno StatFs(ref FileSystemInfo stat)
        {
            return Errno.NotImplemented;
        }

        public virtual Errno Stat(string path, ref FileEntryInfo stat)
        {
            return Errno.NotImplemented;
        }

        public virtual Errno ReadLink(string path, ref string dest)
        {
            return Errno.NotImplemented;
        }

        [Flags]
        enum SFSFlags : byte
        {
            RecyledFolder = 64,
            CaseSensitive = 128
        }

        [StructLayout(LayoutKind.Sequential, Pack = 1)]
        struct RootBlock
        {
            public uint blockId;
            public uint blockChecksum;
            public uint blockSelfPointer;
            public ushort version;
            public ushort sequence;
            public uint datecreated;
            public SFSFlags bits;
            public byte padding1;
            public ushort padding2;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 2)] public uint[] reserved1;
            public ulong firstbyte;
            public ulong lastbyte;
            public uint totalblocks;
            public uint blocksize;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 2)] public uint[] reserved2;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 8)] public uint[] reserved3;
            public uint bitmapbase;
            public uint adminspacecontainer;
            public uint rootobjectcontainer;
            public uint extentbnoderoot;
            public uint objectnoderoot;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 3)] public uint[] reserved4;
        }
    }
}