Aaru/SCSI/Modes/10.cs

// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : 10.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Device structures decoders.
//
// --[ Description ] ----------------------------------------------------------
//
//     Decodes SCSI MODE PAGE 10h: XOR control mode page.
//
// --[ 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.Text;

namespace DiscImageChef.Decoders.SCSI
{
    public static partial class Modes
    {
        #region Mode Page 0x10: XOR control mode page
        /// <summary>
        /// XOR control mode page
        /// Page code 0x10
        /// 24 bytes in SBC-1, SBC-2
        /// </summary>
        public struct ModePage_10
        {
            /// <summary>
            /// Parameters can be saved
            /// </summary>
            public bool PS;
            /// <summary>
            /// Disables XOR operations
            /// </summary>
            public bool XORDIS;
            /// <summary>
            /// Maximum transfer length in blocks for a XOR command
            /// </summary>
            public uint MaxXorWrite;
            /// <summary>
            /// Maximum regenerate length in blocks
            /// </summary>
            public uint MaxRegenSize;
            /// <summary>
            /// Maximum transfer length in blocks for READ during a rebuild
            /// </summary>
            public uint MaxRebuildRead;
            /// <summary>
            /// Minimum time in ms between READs during a rebuild
            /// </summary>
            public ushort RebuildDelay;
        }

        public static ModePage_10? DecodeModePage_10(byte[] pageResponse)
        {
            if((pageResponse?[0] & 0x40) == 0x40) return null;

            if((pageResponse?[0] & 0x3F) != 0x10) return null;

            if(pageResponse[1] + 2 != pageResponse.Length) return null;

            if(pageResponse.Length < 24) return null;

            ModePage_10 decoded = new ModePage_10();

            decoded.PS |= (pageResponse[0] & 0x80) == 0x80;

            decoded.XORDIS |= (pageResponse[2] & 0x02) == 0x02;
            decoded.MaxXorWrite = (uint)((pageResponse[4] << 24) + (pageResponse[5] << 16) + (pageResponse[6] << 8) +
                                         pageResponse[7]);
            decoded.MaxRegenSize = (uint)((pageResponse[12] << 24) + (pageResponse[13] << 16) +
                                          (pageResponse[14] << 8) + pageResponse[15]);
            decoded.MaxRebuildRead = (uint)((pageResponse[16] << 24) + (pageResponse[17] << 16) +
                                            (pageResponse[18] << 8) + pageResponse[19]);
            decoded.RebuildDelay = (ushort)((pageResponse[22] << 8) + pageResponse[23]);

            return decoded;
        }

        public static string PrettifyModePage_10(byte[] pageResponse)
        {
            return PrettifyModePage_10(DecodeModePage_10(pageResponse));
        }

        public static string PrettifyModePage_10(ModePage_10? modePage)
        {
            if(!modePage.HasValue) return null;

            ModePage_10 page = modePage.Value;
            StringBuilder sb = new StringBuilder();

            sb.AppendLine("SCSI XOR control mode page:");

            if(page.PS) sb.AppendLine("\tParameters can be saved");

            if(page.XORDIS) sb.AppendLine("\tXOR operations are disabled");
            else
            {
                if(page.MaxXorWrite > 0)
                    sb.AppendFormat("\tDrive accepts a maximum of {0} blocks in a single XOR WRITE command",
                                    page.MaxXorWrite).AppendLine();
                if(page.MaxRegenSize > 0)
                    sb.AppendFormat("\tDrive accepts a maximum of {0} blocks in a REGENERATE command",
                                    page.MaxRegenSize).AppendLine();
                if(page.MaxRebuildRead > 0)
                    sb.AppendFormat("\tDrive accepts a maximum of {0} blocks in a READ command during rebuild",
                                    page.MaxRebuildRead).AppendLine();
                if(page.RebuildDelay > 0)
                    sb.AppendFormat("\tDrive needs a minimum of {0} ms between READ commands during rebuild",
                                    page.RebuildDelay).AppendLine();
            }

            return sb.ToString();
        }
        #endregion Mode Page 0x10: XOR control mode page
    }
}