// ZipFile.Save.cs
// ------------------------------------------------------------------
//
// Copyright (c) 2009 Dino Chiesa.
// All rights reserved.
//
// This code module is part of DotNetZip, a zipfile class library.
//
// ------------------------------------------------------------------
//
// This code is licensed under the Microsoft Public License.
// See the file License.txt for the license details.
// More info on: http://dotnetzip.codeplex.com
//
// ------------------------------------------------------------------
//
// last saved (in emacs):
// Time-stamp: <2010-February-26 14:00:30>
//
// ------------------------------------------------------------------
//
// This module defines the methods for Save operations on zip files.
//
// ------------------------------------------------------------------
//
using System;
using System.IO;
using System.Collections.Generic;
namespace Ionic.Zip
{
public partial class ZipFile
{
/// <summary>
/// Saves the Zip archive to a file, specified by the Name property of the <c>ZipFile</c>.
/// </summary>
///
/// <remarks>
/// <para>
/// The <c>ZipFile</c> instance is written to storage, typically a zip file in a
/// filesystem, only when the caller calls <c>Save</c>. The Save operation writes
/// the zip content to a temporary file, and then renames the temporary file
/// to the desired name. If necessary, this method will delete a pre-existing file
/// before the rename.
/// </para>
///
/// <para> The <see cref="ZipFile.Name"/> property is specified either
/// explicitly, or implicitly using one of the parameterized ZipFile
/// constructors. For COM Automation clients, the <c>Name</c> property must be
/// set explicitly, because COM Automation clients cannot call parameterized
/// constructors. </para>
///
/// <para>
/// When using a filesystem file for the Zip output, it is possible to call
/// <c>Save</c> multiple times on the <c>ZipFile</c> instance. With each call the zip
/// content is re-written to the same output file.
/// </para>
///
/// <para>
/// Data for entries that have been added to the <c>ZipFile</c> instance is written
/// to the output when the <c>Save</c> method is called. This means that the input
/// streams for those entries must be available at the time the application calls
/// <c>Save</c>. If, for example, the application adds entries with <c>AddEntry</c>
/// using a dynamically-allocated <c>MemoryStream</c>, the memory stream must not
/// have been disposed before the call to <c>Save</c>. See the <see
/// cref="ZipEntry.InputStream"/> property for more discussion of the availability
/// requirements of the input stream for an entry, and an approach for providing
/// just-in-time stream lifecycle management.
/// </para>
///
/// </remarks>
///
/// <seealso cref="Ionic.Zip.ZipFile.AddEntry(String, System.IO.Stream)"/>
///
/// <exception cref="Ionic.Zip.BadStateException">
/// Thrown if you haven't specified a location or stream for saving the zip,
/// either in the constructor or by setting the Name property, or if you try to
/// save a regular zip archive to a filename with a .exe extension.
/// </exception>
///
public void Save()
{
try
{
bool thisSaveUsedZip64 = false;
_saveOperationCanceled = false;
_numberOfSegmentsForMostRecentSave = 0;
OnSaveStarted();
if (WriteStream == null)
throw new BadStateException("You haven't specified where to save the zip.");
if (_name != null && _name.EndsWith(".exe") && !_SavingSfx)
throw new BadStateException("You specified an EXE for a plain zip file.");
// check if modified, before saving.
if (!_contentsChanged)
{
OnSaveCompleted();
if (Verbose) StatusMessageTextWriter.WriteLine("No save is necessary....");
return;
}
Reset();
if (Verbose) StatusMessageTextWriter.WriteLine("saving....");
// validate the number of entries
if (_entries.Count >= 0xFFFF && _zip64 == Zip64Option.Never)
throw new ZipException("The number of entries is 65535 or greater. Consider setting the UseZip64WhenSaving property on the ZipFile instance.");
// write an entry in the zip for each file
int n = 0;
// workitem 9831
ICollection<ZipEntry> c = (SortEntriesBeforeSaving) ? EntriesSorted : Entries;
foreach (ZipEntry e in c) // _entries.Values
{
OnSaveEntry(n, e, true);
e.Write(WriteStream);
if (_saveOperationCanceled)
break;
n++;
OnSaveEntry(n, e, false);
if (_saveOperationCanceled)
break;
// Some entries can be skipped during the save.
if (e.IncludedInMostRecentSave)
thisSaveUsedZip64 |= e.OutputUsedZip64.Value;
}
if (_saveOperationCanceled)
return;
var zss = WriteStream as ZipSegmentedStream;
_numberOfSegmentsForMostRecentSave = (zss!=null)
? zss.CurrentSegment
: 1;
bool directoryNeededZip64 = ZipOutput.WriteCentralDirectoryStructure(WriteStream,
c,
_numberOfSegmentsForMostRecentSave,
_zip64,
Comment,
ProvisionalAlternateEncoding);
OnSaveEvent(ZipProgressEventType.Saving_AfterSaveTempArchive);
_hasBeenSaved = true;
_contentsChanged = false;
thisSaveUsedZip64 |= directoryNeededZip64;
_OutputUsesZip64 = new Nullable<bool>(thisSaveUsedZip64);
// do the rename as necessary
if (_name != null &&
(_temporaryFileName!=null || zss != null))
{
// _temporaryFileName may remain null if we are writing to a stream.
// only close the stream if there is a file behind it.
WriteStream.Close();
#if !NETCF
WriteStream.Dispose();
#endif
if (_saveOperationCanceled)
return;
if ((_fileAlreadyExists) && (this._readstream != null))
{
// This means we opened and read a zip file.
// If we are now saving to the same file, we need to close the
// orig file, first.
this._readstream.Close();
this._readstream = null;
// the archiveStream for each entry needs to be null
foreach (var e in c) e._archiveStream = null;
}
if (File.Exists(_name))
{
// We do not just call File.Replace() here because
// there is a possibility that the TEMP volume is different
// that the volume for the final file (c:\ vs d:\).
// So we need to do a Delete+Move pair.
//
// Ideally this would be transactional.
//
// It's possible that the delete succeeds and the move fails.
// in that case, we're hosed, and we'll throw.
//
// Could make this more complicated by moving (renaming) the first file, then
// moving the second, then deleting the first file. But the
// error handling and unwrap logic just gets more complicated.
//
// Better to just keep it simple.
File.Delete(_name);
}
OnSaveEvent(ZipProgressEventType.Saving_BeforeRenameTempArchive);
File.Move((zss != null) ? zss.CurrentName : _temporaryFileName, _name);
OnSaveEvent(ZipProgressEventType.Saving_AfterRenameTempArchive);
_fileAlreadyExists = true;
}
NotifyEntriesSaveComplete(c);
OnSaveCompleted();
_JustSaved = true;
}
// workitem 5043
finally
{
CleanupAfterSaveOperation();
}
return;
}
private void NotifyEntriesSaveComplete(ICollection<ZipEntry> c)
{
foreach (ZipEntry e in c)
{
e.NotifySaveComplete();
}
}
private void RemoveTempFile()
{
try
{
if (File.Exists(_temporaryFileName))
{
File.Delete(_temporaryFileName);
}
}
catch (Exception ex1)
{
if (Verbose)
StatusMessageTextWriter.WriteLine("ZipFile::Save: could not delete temp file: {0}.", ex1.Message);
}
}
private void CleanupAfterSaveOperation()
{
if (_name != null)
{
// close the stream if there is a file behind it.
if (_writestream != null)
{
try
{
// workitem 7704
#if NETCF
_writestream.Close();
#else
_writestream.Dispose();
#endif
}
catch { }
}
_writestream = null;
if (_temporaryFileName != null)
{
RemoveTempFile();
_temporaryFileName = null;
}
}
}
/// <summary>
/// Save the file to a new zipfile, with the given name.
/// </summary>
///
/// <remarks>
/// <para>
/// This method allows the application to explicitly specify the name of the zip
/// file when saving. Use this when creating a new zip file, or when
/// updating a zip archive.
/// </para>
///
/// <para>
/// An application can also save a zip archive in several places by calling this
/// method multiple times in succession, with different filenames.
/// </para>
///
/// <para>
/// The <c>ZipFile</c> instance is written to storage, typically a zip file in a
/// filesystem, only when the caller calls <c>Save</c>. The Save operation writes
/// the zip content to a temporary file, and then renames the temporary file
/// to the desired name. If necessary, this method will delete a pre-existing file
/// before the rename.
/// </para>
///
/// </remarks>
///
/// <exception cref="System.ArgumentException">
/// Thrown if you specify a directory for the filename.
/// </exception>
///
/// <param name="fileName">
/// The name of the zip archive to save to. Existing files will
/// be overwritten with great prejudice.
/// </param>
///
/// <example>
/// This example shows how to create and Save a zip file.
/// <code>
/// using (ZipFile zip = new ZipFile())
/// {
/// zip.AddDirectory(@"c:\reports\January");
/// zip.Save("January.zip");
/// }
/// </code>
///
/// <code lang="VB">
/// Using zip As New ZipFile()
/// zip.AddDirectory("c:\reports\January")
/// zip.Save("January.zip")
/// End Using
/// </code>
///
/// </example>
///
/// <example>
/// This example shows how to update a zip file.
/// <code>
/// using (ZipFile zip = ZipFile.Read("ExistingArchive.zip"))
/// {
/// zip.AddFile("NewData.csv");
/// zip.Save("UpdatedArchive.zip");
/// }
/// </code>
///
/// <code lang="VB">
/// Using zip As ZipFile = ZipFile.Read("ExistingArchive.zip")
/// zip.AddFile("NewData.csv")
/// zip.Save("UpdatedArchive.zip")
/// End Using
/// </code>
///
/// </example>
public void Save(String fileName)
{
// Check for the case where we are re-saving a zip archive
// that was originally instantiated with a stream. In that case,
// the _name will be null. If so, we set _writestream to null,
// which insures that we'll cons up a new WriteStream (with a filesystem
// file backing it) in the Save() method.
if (_name == null)
_writestream = null;
_name = fileName;
if (Directory.Exists(_name))
throw new ZipException("Bad Directory", new System.ArgumentException("That name specifies an existing directory. Please specify a filename.", "fileName"));
_contentsChanged = true;
_fileAlreadyExists = File.Exists(_name);
Save();
}
/// <summary>
/// Save the zip archive to the specified stream.
/// </summary>
///
/// <remarks>
/// <para>
/// The <c>ZipFile</c> instance is written to storage - typically a zip file
/// in a filesystem, but using this overload, the storage can be anything
/// accessible via a writable stream - only when the caller calls <c>Save</c>.
/// </para>
///
/// <para>
/// Use this method to save the zip content to a stream directly. A common
/// scenario is an ASP.NET application that dynamically generates a zip file
/// and allows the browser to download it. The application can call
/// <c>Save(Response.OutputStream)</c> to write a zipfile directly to the
/// output stream, without creating a zip file on the disk on the ASP.NET
/// server.
/// </para>
///
/// <para>
/// Be careful when saving a file to a non-seekable stream, including
/// <c>Response.OutputStream</c>. When DotNetZip writes to a non-seekable
/// stream, the zip archive is formatted in such a way that may not be
/// compatible with all zip tools on all platforms. It's a perfectly legal
/// and compliant zip file, but some people have reported problems opening
/// files produced this way using the Mac OS archive utility.
/// </para>
///
/// </remarks>
///
/// <example>
///
/// This example saves the zipfile content into a MemoryStream, and
/// then gets the array of bytes from that MemoryStream.
///
/// <code lang="C#">
/// using (var zip = new Ionic.Zip.ZipFile())
/// {
/// zip.CompressionLevel= Ionic.Zlib.CompressionLevel.BestCompression;
/// zip.Password = "VerySecret.";
/// zip.Encryption = EncryptionAlgorithm.WinZipAes128;
/// zip.AddFile(sourceFileName);
/// MemoryStream output = new MemoryStream();
/// zip.Save(output);
///
/// byte[] zipbytes = output.ToArray();
/// }
/// </code>
/// </example>
///
/// <param name="outputStream">
/// The <c>System.IO.Stream</c> to write to. It must be writable.
/// </param>
public void Save(Stream outputStream)
{
if (!outputStream.CanWrite)
throw new ArgumentException("The outputStream must be a writable stream.");
// if we had a filename to save to, we are now obliterating it.
_name = null;
_writestream = new CountingStream(outputStream);
_contentsChanged = true;
_fileAlreadyExists = false;
Save();
}
}
internal class ZipOutput
{
public static bool WriteCentralDirectoryStructure(Stream s,
ICollection<ZipEntry> entries,
uint numSegments,
Zip64Option zip64,
String comment,
System.Text.Encoding encoding)
{
var zss = s as ZipSegmentedStream;
if (zss != null)
zss.ContiguousWrite = true;
// write to a memory stream in order to keep the
// CDR contiguous
var ms = new MemoryStream();
foreach (ZipEntry e in entries)
{
if (e.IncludedInMostRecentSave)
{
// this writes a ZipDirEntry corresponding to the ZipEntry
e.WriteCentralDirectoryEntry(ms);
}
}
var a = ms.ToArray();
s.Write(a, 0, a.Length);
// We need to keep track of the start and
// Finish of the Central Directory Structure.
// Cannot always use WriteStream.Length or Position; some streams do
// not support these. (eg, ASP.NET Response.OutputStream) In those
// cases we have a CountingStream.
// Also, we cannot just set Start as s.Position bfore the write, and Finish
// as s.Position after the write. In a split zip, the write may actually
// flip to the next segment. In that case, Start will be zero. But we
// don't know that til after we know the size of the thing to write. So the
// answer is to compute the directory, then ask the ZipSegmentedStream which
// segment that directory would fall in, it it were written. Then, include
// that data into the directory, and finally, write the directory to the
// output stream.
var output = s as CountingStream;
long Finish = (output != null) ? output.ComputedPosition : s.Position; // BytesWritten
long Start = Finish - a.Length;
// need to know which segment the EOCD record starts in
UInt32 startSegment = (zss != null)
? zss.CurrentSegment
: 0;
Int64 SizeOfCentralDirectory = Finish - Start;
int countOfEntries = CountEntries(entries);
bool needZip64CentralDirectory =
zip64 == Zip64Option.Always ||
countOfEntries >= 0xFFFF ||
SizeOfCentralDirectory > 0xFFFFFFFF ||
Start > 0xFFFFFFFF;
byte[] a2 = null;
// emit ZIP64 extensions as required
if (needZip64CentralDirectory)
{
if (zip64 == Zip64Option.Never)
{
#if NETCF
throw new ZipException("The archive requires a ZIP64 Central Directory. Consider enabling ZIP64 extensions.");
#else
System.Diagnostics.StackFrame sf = new System.Diagnostics.StackFrame(1);
if (sf.GetMethod().DeclaringType == typeof(ZipFile))
throw new ZipException("The archive requires a ZIP64 Central Directory. Consider setting the ZipFile.UseZip64WhenSaving property.");
else
throw new ZipException("The archive requires a ZIP64 Central Directory. Consider setting the ZipOutputStream.EnableZip64 property.");
#endif
}
a = GenZip64EndOfCentralDirectory(Start, Finish, countOfEntries, numSegments);
a2 = GenCentralDirectoryFooter(Start, Finish, zip64, countOfEntries, comment, encoding);
if (startSegment != 0)
{
UInt32 thisSegment = zss.ComputeSegment(a.Length + a2.Length);
int i = 16;
// number of this disk
Array.Copy(BitConverter.GetBytes(thisSegment), 0, a, i, 4);
i += 4;
// number of the disk with the start of the central directory
//Array.Copy(BitConverter.GetBytes(startSegment), 0, a, i, 4);
Array.Copy(BitConverter.GetBytes(thisSegment), 0, a, i, 4);
i = 60;
// offset 60
// number of the disk with the start of the zip64 eocd
Array.Copy(BitConverter.GetBytes(thisSegment), 0, a, i, 4);
i += 4;
i += 8;
// offset 72
// total number of disks
Array.Copy(BitConverter.GetBytes(thisSegment), 0, a, i, 4);
}
s.Write(a, 0, a.Length);
}
else
a2 = GenCentralDirectoryFooter(Start, Finish, zip64, countOfEntries, comment, encoding);
// now, the regular footer
if (startSegment != 0)
{
// The assumption is the central directory is never split across
// segment boundaries.
UInt16 thisSegment = (UInt16) zss.ComputeSegment(a2.Length);
int i = 4;
// number of this disk
Array.Copy(BitConverter.GetBytes(thisSegment), 0, a2, i, 2);
i += 2;
// number of the disk with the start of the central directory
//Array.Copy(BitConverter.GetBytes((UInt16)startSegment), 0, a2, i, 2);
Array.Copy(BitConverter.GetBytes(thisSegment), 0, a2, i, 2);
i += 2;
}
s.Write(a2, 0, a2.Length);
// reset the contiguous write property if necessary
if (zss != null)
zss.ContiguousWrite = false;
return needZip64CentralDirectory;
}
private static byte[] GenCentralDirectoryFooter(long StartOfCentralDirectory,
long EndOfCentralDirectory,
Zip64Option zip64,
int entryCount,
string comment,
System.Text.Encoding encoding)
{
int j = 0;
int bufferLength = 22;
byte[] block = null;
Int16 commentLength = 0;
if ((comment != null) && (comment.Length != 0))
{
block = encoding.GetBytes(comment);
commentLength = (Int16)block.Length;
}
bufferLength += commentLength;
byte[] bytes = new byte[bufferLength];
int i = 0;
// signature
byte[] sig = BitConverter.GetBytes(ZipConstants.EndOfCentralDirectorySignature);
Array.Copy(sig, 0, bytes, i, 4);
i+=4;
// number of this disk
// (this number may change later)
bytes[i++] = 0;
bytes[i++] = 0;
// number of the disk with the start of the central directory
// (this number may change later)
bytes[i++] = 0;
bytes[i++] = 0;
// handle ZIP64 extensions for the end-of-central-directory
if (entryCount >= 0xFFFF || zip64 == Zip64Option.Always)
{
// the ZIP64 version.
for (j = 0; j < 4; j++)
bytes[i++] = 0xFF;
}
else
{
// the standard version.
// total number of entries in the central dir on this disk
bytes[i++] = (byte)(entryCount & 0x00FF);
bytes[i++] = (byte)((entryCount & 0xFF00) >> 8);
// total number of entries in the central directory
bytes[i++] = (byte)(entryCount & 0x00FF);
bytes[i++] = (byte)((entryCount & 0xFF00) >> 8);
}
// size of the central directory
Int64 SizeOfCentralDirectory = EndOfCentralDirectory - StartOfCentralDirectory;
if (SizeOfCentralDirectory >= 0xFFFFFFFF || StartOfCentralDirectory >= 0xFFFFFFFF)
{
// The actual data is in the ZIP64 central directory structure
for (j = 0; j < 8; j++)
bytes[i++] = 0xFF;
}
else
{
// size of the central directory (we just get the low 4 bytes)
bytes[i++] = (byte)(SizeOfCentralDirectory & 0x000000FF);
bytes[i++] = (byte)((SizeOfCentralDirectory & 0x0000FF00) >> 8);
bytes[i++] = (byte)((SizeOfCentralDirectory & 0x00FF0000) >> 16);
bytes[i++] = (byte)((SizeOfCentralDirectory & 0xFF000000) >> 24);
// offset of the start of the central directory (we just get the low 4 bytes)
bytes[i++] = (byte)(StartOfCentralDirectory & 0x000000FF);
bytes[i++] = (byte)((StartOfCentralDirectory & 0x0000FF00) >> 8);
bytes[i++] = (byte)((StartOfCentralDirectory & 0x00FF0000) >> 16);
bytes[i++] = (byte)((StartOfCentralDirectory & 0xFF000000) >> 24);
}
// zip archive comment
if ((comment == null) || (comment.Length == 0))
{
// no comment!
bytes[i++] = (byte)0;
bytes[i++] = (byte)0;
}
else
{
// the size of our buffer defines the max length of the comment we can write
if (commentLength + i + 2 > bytes.Length) commentLength = (Int16)(bytes.Length - i - 2);
bytes[i++] = (byte)(commentLength & 0x00FF);
bytes[i++] = (byte)((commentLength & 0xFF00) >> 8);
if (commentLength != 0)
{
// now actually write the comment itself into the byte buffer
for (j = 0; (j < commentLength) && (i + j < bytes.Length); j++)
{
bytes[i + j] = block[j];
}
i += j;
}
}
// s.Write(bytes, 0, i);
return bytes;
}
private static byte[] GenZip64EndOfCentralDirectory(long StartOfCentralDirectory,
long EndOfCentralDirectory,
int entryCount,
uint numSegments)
{
const int bufferLength = 12 + 44 + 20;
byte[] bytes = new byte[bufferLength];
int i = 0;
// signature
byte[] sig = BitConverter.GetBytes(ZipConstants.Zip64EndOfCentralDirectoryRecordSignature);
Array.Copy(sig, 0, bytes, i, 4);
i+=4;
// There is a possibility to include "Extensible" data in the zip64
// end-of-central-dir record. I cannot figure out what it might be used to
// store, so the size of this record is always fixed. Maybe it is used for
// strong encryption data? That is for another day.
long DataSize = 44;
Array.Copy(BitConverter.GetBytes(DataSize), 0, bytes, i, 8);
i += 8;
// offset 12
// VersionMadeBy = 45;
bytes[i++] = 45;
bytes[i++] = 0x00;
// VersionNeededToExtract = 45;
bytes[i++] = 45;
bytes[i++] = 0x00;
// offset 16
// number of the disk, and the disk with the start of the central dir.
// (this may change later)
for (int j = 0; j < 8; j++)
bytes[i++] = 0x00;
// offset 24
long numberOfEntries = entryCount;
Array.Copy(BitConverter.GetBytes(numberOfEntries), 0, bytes, i, 8);
i += 8;
Array.Copy(BitConverter.GetBytes(numberOfEntries), 0, bytes, i, 8);
i += 8;
// offset 40
Int64 SizeofCentraldirectory = EndOfCentralDirectory - StartOfCentralDirectory;
Array.Copy(BitConverter.GetBytes(SizeofCentraldirectory), 0, bytes, i, 8);
i += 8;
Array.Copy(BitConverter.GetBytes(StartOfCentralDirectory), 0, bytes, i, 8);
i += 8;
// offset 56
// now, the locator
// signature
sig = BitConverter.GetBytes(ZipConstants.Zip64EndOfCentralDirectoryLocatorSignature);
Array.Copy(sig, 0, bytes, i, 4);
i+=4;
// offset 60
// number of the disk with the start of the zip64 eocd
// (this will change later) (it will?)
uint x2 = (numSegments==0)?0:(uint)(numSegments-1);
Array.Copy(BitConverter.GetBytes(x2), 0, bytes, i, 4);
i+=4;
// offset 64
// relative offset of the zip64 eocd
Array.Copy(BitConverter.GetBytes(EndOfCentralDirectory), 0, bytes, i, 8);
i += 8;
// offset 72
// total number of disks
// (this will change later)
Array.Copy(BitConverter.GetBytes(numSegments-1), 0, bytes, i, 4);
i+=4;
return bytes;
}
private static int CountEntries(ICollection<ZipEntry> _entries)
{
// Cannot just emit _entries.Count, because some of the entries
// may have been skipped.
int count = 0;
foreach (var entry in _entries)
if (entry.IncludedInMostRecentSave) count++;
return count;
}
}
}
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