Files
duplicati/Duplicati/Library/Main/Operation/RestoreHandlerMetadataStorage.cs
T

28 lines
4.8 KiB
C#

// Copyright (C) 2015, The Duplicati Team
// http://www.duplicati.com, info@duplicati.com
//
// 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, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
using System;
using System.IO;
using Duplicati.Library.Utility;
using System.Collections.Generic;
namespace Duplicati.Library.Main.Operation
{
public class RestoreHandlerMetadataStorage : IDisposable
{
private TempFile m_temp;
private FileStream m_stream;
private long m_entries;
private long m_filepos;
public RestoreHandlerMetadataStorage()
{
m_temp = new TempFile();
m_stream = File.Open(m_temp, FileMode.Truncate, FileAccess.ReadWrite, FileShare.None);
}
public void Add(string path, Stream data)
{
var datalen = data.Length;
if (datalen > Int32.MaxValue)
throw new ArgumentOutOfRangeException("Metadata is larger than int32");
var pathbytes = System.Text.Encoding.UTF8.GetBytes(path);
var pathlen = BitConverter.GetBytes(pathbytes.LongLength);
var entrylen = BitConverter.GetBytes(datalen);
var totalsize = pathbytes.Length + pathlen.Length + entrylen.Length + datalen;
m_stream.Position = m_filepos;
m_stream.Write(pathlen, 0, pathlen.Length);
m_stream.Write(pathbytes, 0, pathbytes.Length);
m_stream.Write(entrylen, 0, entrylen.Length);
data.CopyTo(m_stream);
if (m_stream.Position != m_filepos + totalsize)
throw new Exception("Bad file write!");
m_filepos += totalsize;
m_entries++;
}
private void CheckedRead(byte[] buffer, int offset, int count)
{
int r;
while (count > 0 && (r = m_stream.Read(buffer, offset, count)) > 0)
{
offset += r;
count -= r;
}
if (count != 0)
throw new Exception("Bad file read");
}
public IEnumerable<KeyValuePair<string, Stream>> Records
{
get
{
long pos = 0;
var bf = BitConverter.GetBytes(0L);
var buf = new byte[8 * 1024];
Logging.Log.WriteMessage(string.Format("The metadata storage file has {0} entries and takes up {1}", m_entries, Library.Utility.Utility.FormatSizeString(m_stream.Length)), Duplicati.Library.Logging.LogMessageType.Profiling);
using(new Logging.Timer("Read metadata from file"))
for(var e = 0L; e < m_entries; e++)
{
m_stream.Position = pos;
CheckedRead(bf, 0, bf.Length);
var stringlen = BitConverter.ToInt64(bf, 0);
var strbuf = stringlen > buf.Length ? new byte[stringlen] : buf;
CheckedRead(strbuf, 0, (int)stringlen);
var path = System.Text.Encoding.UTF8.GetString(strbuf, 0, (int)stringlen);
CheckedRead(bf, 0, bf.Length);
var datalen = BitConverter.ToInt64(bf, 0);
if (datalen > Int32.MaxValue)
throw new ArgumentOutOfRangeException("Metadata is larger than int32");
var databuf = datalen > buf.Length ? new byte[datalen] : buf;
CheckedRead(databuf, 0, (int)datalen);
pos += datalen + stringlen + bf.Length + bf.Length;
yield return new KeyValuePair<string, Stream>(path, new MemoryStream(databuf, 0, (int)datalen));
}
}
}
#region IDisposable implementation
public void Dispose()
{
if (m_stream != null)
try { m_stream.Dispose(); }
catch { }
finally { m_stream = null; }
if (m_temp != null)
try { m_temp.Dispose(); }
catch { }
finally { m_temp = null; }
}
#endregion
}
}