duplicati/Duplicati/Library/Main/Operation/Common/IndexVolumeCreator.cs

197 lines
8.4 KiB
C#

// Copyright (C) 2025, The Duplicati Team
// https://duplicati.com, hello@duplicati.com
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
using Duplicati.Library.Main.Volumes;
using Duplicati.Library.Utility;
namespace Duplicati.Library.Main.Operation.Common
{
// TODO: Remove this class and simply rely on the database to create the index files
/// <summary>
/// A collection class for keeping the temporary data required to build an index file
/// </summary>
internal class TemporaryIndexVolume
{
/// <summary>
/// The block hashes
/// </summary>
private readonly FileBackedStringList blockHashes = new();
/// <summary>
/// The blocklist hashes
/// </summary>
private readonly FileBackedStringList blockListHashes = new();
/// <summary>
/// The known block list hashes
/// </summary>
private readonly HashSet<string> knownBlockListHashes = new();
/// <summary>
/// Cached copy of the blocklist hash size
/// </summary>
private readonly int m_blockhashsize;
/// <summary>
/// Initializes a new instance of the
/// <see cref="T:Duplicati.Library.Main.Operation.Common.TemporaryIndexVolume"/> class.
/// </summary>
/// <param name="options">The options used in this run.</param>
public TemporaryIndexVolume(Options options)
{
m_blockhashsize = options.BlockhashSize;
}
/// <summary>
/// Creates an index volume with the temporary contents
/// </summary>
/// <param name="blockfilename">The name of the block file.</param>
/// <param name="options">The options used in this run.</param>
/// <param name="database">The database to use.</param>
/// <param name="cancellationToken">The cancellation token to use.</param>
/// <returns>The index volume.</returns>
public async Task<IndexVolumeWriter> CreateVolume(string blockfilename, Options options, DatabaseCommon database, CancellationToken cancellationToken)
{
var w = new IndexVolumeWriter(options);
w.VolumeID = await database.RegisterRemoteVolumeAsync(w.RemoteFilename, RemoteVolumeType.Index, RemoteVolumeState.Temporary, cancellationToken).ConfigureAwait(false);
var enumerator = blockListHashes.GetEnumerator();
while (enumerator.MoveNext())
{
var hash = enumerator.Current;
enumerator.MoveNext();
var data = Convert.FromBase64String(enumerator.Current);
w.WriteBlocklist(hash, data, 0, data.Length);
}
w.StartVolume(blockfilename);
foreach (var n in blockHashes)
{
var args = n.Split(new char[] { ':' }, 2);
w.AddBlock(args[1], long.Parse(args[0]));
}
return w;
}
/// <summary>
/// Copies all entries from this temporary instance to the target
/// </summary>
/// <param name="target">The target volume.</param>
/// <param name="onlyBlocklistHashes">Only copies the blocklist hashes</param>
public void CopyTo(TemporaryIndexVolume target, bool onlyBlocklistHashes)
{
if (!onlyBlocklistHashes)
foreach (var n in blockHashes)
target.blockHashes.Add(n);
var enumerator = blockListHashes.GetEnumerator();
while (enumerator.MoveNext())
{
var hash = enumerator.Current;
enumerator.MoveNext();
// Filter duplicates
if (target.knownBlockListHashes.Contains(hash))
continue;
target.knownBlockListHashes.Add(hash);
target.blockListHashes.Add(hash);
target.blockListHashes.Add(enumerator.Current);
}
}
/// <summary>
/// Adds a single block hash to the index
/// </summary>
/// <param name="hash">The hash of the block.</param>
/// <param name="size">The size of the block.</param>
public void AddBlock(string hash, long size)
{
blockHashes.Add(size.ToString() + ":" + hash);
}
/// <summary>
/// Adds a block list hash to the index
/// </summary>
/// <param name="hash">The hash of the block to add.</param>
/// <param name="size">The size of the block.</param>
/// <param name="data">The block contents.</param>
public void AddBlockListHash(string hash, long size, byte[] data)
{
// Filter out duplicates to reduce size
if (knownBlockListHashes.Contains(hash))
return;
knownBlockListHashes.Add(hash);
if (size % m_blockhashsize != 0)
throw new ArgumentException($"The {nameof(size)} value is {size}, but it must be evenly divisible by the blockhash size ({m_blockhashsize})", nameof(size));
blockListHashes.Add(hash);
blockListHashes.Add(Convert.ToBase64String(data, 0, (int)size));
}
}
/// <summary>
/// Encapsulates creating an index file from the database contents
/// </summary>
internal static class IndexVolumeCreator
{
public static async Task<IndexVolumeWriter> CreateIndexVolume(string blockname, Options options, Common.DatabaseCommon database, CancellationToken cancellationToken)
{
using (var h = HashFactory.CreateHasher(options.BlockHashAlgorithm))
{
var w = new IndexVolumeWriter(options);
w.VolumeID = await database.RegisterRemoteVolumeAsync(w.RemoteFilename, RemoteVolumeType.Index, RemoteVolumeState.Temporary, cancellationToken).ConfigureAwait(false);
var blockvolume = await database.GetVolumeInfoAsync(blockname, cancellationToken).ConfigureAwait(false);
w.StartVolume(blockname);
foreach (var b in await database.GetBlocksAsync(blockvolume.ID, cancellationToken).ConfigureAwait(false))
w.AddBlock(b.Hash, b.Size);
w.FinishVolume(blockvolume.Hash, blockvolume.Size);
if (options.IndexfilePolicy == Options.IndexFileStrategy.Full)
foreach (var b in await database.GetBlocklistsAsync(blockvolume.ID, options.Blocksize, options.BlockhashSize, cancellationToken).ConfigureAwait(false))
{
var bh = Convert.ToBase64String(h.ComputeHash(b.Item2, 0, b.Item3));
if (bh != b.Item1)
throw new Exception(string.Format("Internal consistency check failed, generated index block has wrong hash, {0} vs {1}", bh, b.Item1));
w.WriteBlocklist(b.Item1, b.Item2, 0, b.Item3);
}
w.Close();
// Register that the index file is tracking the block file
await database.AddIndexBlockLinkAsync(w.VolumeID, blockvolume.ID, cancellationToken).ConfigureAwait(false);
return w;
}
}
}
}