//---------------------------------------------------------------------
// <copyright file="BasicUnpackStreamContext.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// The use and distribution terms for this software are covered by the
// Common Public License 1.0 (http://opensource.org/licenses/cpl.php)
// which can be found in the file CPL.TXT at the root of this distribution.
// By using this software in any fashion, you are agreeing to be bound by
// the terms of this license.
//
// You must not remove this notice, or any other, from this software.
// </copyright>
// <summary>
// Part of the Deployment Tools Foundation project.
// </summary>
//---------------------------------------------------------------------
namespace Microsoft.Deployment.Compression{
using System;
using System.IO;
using System.Diagnostics.CodeAnalysis;
/// <summary>
/// Stream context used to extract a single file from an archive into a memory stream.
/// </summary>
[SuppressMessage("Microsoft.Design", "CA1001:TypesThatOwnDisposableFieldsShouldBeDisposable")]
public class BasicUnpackStreamContext : IUnpackStreamContext
{
private Stream archiveStream;
private Stream fileStream;
/// <summary>
/// Creates a new BasicExtractStreamContext that reads from the specified archive stream.
/// </summary>
/// <param name="archiveStream">Archive stream to read from.</param>
public BasicUnpackStreamContext(Stream archiveStream)
{
this.archiveStream = archiveStream;
}
/// <summary>
/// Gets the stream for the extracted file, or null if no file was extracted.
/// </summary>
public Stream FileStream
{
get
{
return this.fileStream;
}
}
/// <summary>
/// Opens the archive stream for reading. Returns a DuplicateStream instance,
/// so the stream may be virtually opened multiple times.
/// </summary>
/// <param name="archiveNumber">The archive number to open (ignored; 0 is assumed).</param>
/// <param name="archiveName">The name of the archive being opened.</param>
/// <param name="compressionEngine">Instance of the compression engine doing the operations.</param>
/// <returns>A stream from which archive bytes are read.</returns>
public Stream OpenArchiveReadStream(int archiveNumber, string archiveName, CompressionEngine compressionEngine)
{
return new DuplicateStream(this.archiveStream);
}
/// <summary>
/// Does *not* close the stream. The archive stream should be managed by
/// the code that invokes the archive extraction.
/// </summary>
/// <param name="archiveNumber">The archive number of the stream to close.</param>
/// <param name="archiveName">The name of the archive being closed.</param>
/// <param name="stream">The stream being closed.</param>
public void CloseArchiveReadStream(int archiveNumber, string archiveName, Stream stream)
{
// Do nothing.
}
/// <summary>
/// Opens a stream for writing extracted file bytes. The returned stream is a MemoryStream
/// instance, so the file is extracted straight into memory.
/// </summary>
/// <param name="path">Path of the file within the archive.</param>
/// <param name="fileSize">The uncompressed size of the file to be extracted.</param>
/// <param name="lastWriteTime">The last write time of the file.</param>
/// <returns>A stream where extracted file bytes are to be written.</returns>
public Stream OpenFileWriteStream(string path, long fileSize, DateTime lastWriteTime)
{
this.fileStream = new MemoryStream(new byte[fileSize], 0, (int) fileSize, true, true);
return this.fileStream;
}
/// <summary>
/// Does *not* close the file stream. The file stream is saved in memory so it can
/// be read later.
/// </summary>
/// <param name="path">Path of the file within the archive.</param>
/// <param name="stream">The file stream to be closed.</param>
/// <param name="attributes">The attributes of the extracted file.</param>
/// <param name="lastWriteTime">The last write time of the file.</param>
public void CloseFileWriteStream(string path, Stream stream, FileAttributes attributes, DateTime lastWriteTime)
{
// Do nothing.
}
}
}
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