Aaru/DiscImageChef.Core/Devices/Dumping/ResumeSupport.cs

// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : ResumeSupport.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Core algorithms.
//
// --[ Description ] ----------------------------------------------------------
//
//     Contains logic to support dump resuming.
//
// --[ License ] --------------------------------------------------------------
//
//     This program is free software: you can redistribute it and/or modify
//     it under the terms of the GNU General Public License as
//     published by the Free Software Foundation, either version 3 of the
//     License, or (at your option) any later version.
//
//     This program 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 General Public License for more details.
//
//     You should have received a copy of the GNU General Public License
//     along with this program.  If not, see <http://www.gnu.org/licenses/>.
//
// ----------------------------------------------------------------------------
// Copyright © 2011-2018 Natalia Portillo
// ****************************************************************************/

using System;
using System.Collections.Generic;
using DiscImageChef.Metadata;
using Extents;
using Schemas;
using PlatformID = DiscImageChef.Interop.PlatformID;

namespace DiscImageChef.Core.Devices.Dumping
{
    /// <summary>
    /// Implements resume support
    /// </summary>
    static class ResumeSupport
    {
        /// <summary>
        /// Process resume
        /// </summary>
        /// <param name="isLba">If drive is LBA</param>
        /// <param name="removable">If media is removable from device</param>
        /// <param name="blocks">Media blocks</param>
        /// <param name="manufacturer">Device manufacturer</param>
        /// <param name="model">Device model</param>
        /// <param name="serial">Device serial</param>
        /// <param name="platform">Platform where the dump is made</param>
        /// <param name="resume">Previous resume, or null</param>
        /// <param name="currentTry">Current dumping hardware</param>
        /// <param name="extents">Dumped extents</param>
        /// <exception cref="NotImplementedException">If device uses CHS addressing</exception>
        /// <exception cref="InvalidOperationException">If the provided resume does not correspond with the current in progress dump</exception>
        internal static void Process(bool isLba, bool removable, ulong blocks, string manufacturer, string model,
                                   string serial, PlatformID platform, ref Resume resume,
                                   ref DumpHardwareType currentTry, ref ExtentsULong extents)
        {
            if(resume != null)
            {
                if(!isLba) throw new NotImplementedException("Resuming CHS devices is currently not supported.");

                if(resume.Removable != removable)
                    throw new
                        InvalidOperationException($"Resume file specifies a {(resume.Removable ? "removable" : "non removable")} device but you're requesting to dump a {(removable ? "removable" : "non removable")} device, not continuing...");

                if(resume.LastBlock != blocks - 1)
                    throw new
                        InvalidOperationException($"Resume file specifies a device with {resume.LastBlock + 1} blocks but you're requesting to dump one with {blocks} blocks, not continuing...");

                foreach(DumpHardwareType oldtry in resume.Tries)
                {
                    if(!removable)
                    {
                        if(oldtry.Manufacturer != manufacturer)
                            throw new
                                InvalidOperationException($"Resume file specifies a device manufactured by {oldtry.Manufacturer} but you're requesting to dump one by {manufacturer}, not continuing...");

                        if(oldtry.Model != model)
                            throw new
                                InvalidOperationException($"Resume file specifies a device model {oldtry.Model} but you're requesting to dump model {model}, not continuing...");

                        if(oldtry.Serial != serial)
                            throw new
                                InvalidOperationException($"Resume file specifies a device with serial {oldtry.Serial} but you're requesting to dump one with serial {serial}, not continuing...");
                    }

                    if(oldtry.Software == null) throw new InvalidOperationException("Found corrupt resume file, cannot continue...");

                    if(oldtry.Software.Name != "DiscImageChef" ||
                       oldtry.Software.OperatingSystem != platform.ToString() ||
                       oldtry.Software.Version != Version.GetVersion()) continue;

                    if(removable && (oldtry.Manufacturer != manufacturer || oldtry.Model != model ||
                                     oldtry.Serial != serial)) continue;

                    currentTry = oldtry;
                    extents = ExtentsConverter.FromMetadata(currentTry.Extents);
                    break;
                }

                if(currentTry != null) return;

                currentTry = new DumpHardwareType
                {
                    Software = Version.GetSoftwareType(platform),
                    Manufacturer = manufacturer,
                    Model = model,
                    Serial = serial
                };
                resume.Tries.Add(currentTry);
                extents = new ExtentsULong();
            }
            else
            {
                resume = new Resume
                {
                    Tries = new List<DumpHardwareType>(),
                    CreationDate = DateTime.UtcNow,
                    BadBlocks = new List<ulong>(),
                    LastBlock = blocks - 1
                };
                currentTry = new DumpHardwareType
                {
                    Software = Version.GetSoftwareType(platform),
                    Manufacturer = manufacturer,
                    Model = model,
                    Serial = serial
                };
                resume.Tries.Add(currentTry);
                extents = new ExtentsULong();
                resume.Removable = removable;
            }
        }
    }
}