// ZipFile.cs
//
// Copyright (C) 2001 Mike Krueger
// Copyright (C) 2004 John Reilly
//
// This file was translated from java, it was part of the GNU Classpath
// Copyright (C) 2001 Free Software Foundation, Inc.
//
// 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 2
// 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, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//
// Linking this library statically or dynamically with other modules is
// making a combined work based on this library. Thus, the terms and
// conditions of the GNU General Public License cover the whole
// combination.
//
// As a special exception, the copyright holders of this library give you
// permission to link this library with independent modules to produce an
// executable, regardless of the license terms of these independent
// modules, and to copy and distribute the resulting executable under
// terms of your choice, provided that you also meet, for each linked
// independent module, the terms and conditions of the license of that
// module. An independent module is a module which is not derived from
// or based on this library. If you modify this library, you may extend
// this exception to your version of the library, but you are not
// obligated to do so. If you do not wish to do so, delete this
// exception statement from your version.
using System;
using System.Collections;
using System.IO;
using System.Text;
using ICSharpCode.SharpZipLib.Zip.Compression.Streams;
using ICSharpCode.SharpZipLib.Zip.Compression;
namespace ICSharpCode.SharpZipLib.Zip
{
///
/// This class represents a Zip archive. You can ask for the contained
/// entries, or get an input stream for a file entry. The entry is
/// automatically decompressed.
///
/// This class is thread safe: You can open input streams for arbitrary
/// entries in different threads.
///
///
Author of the original java version : Jochen Hoenicke
/// ///
///
/// using System;
/// using System.Text;
/// using System.Collections;
/// using System.IO;
///
/// using ICSharpCode.SharpZipLib.Zip;
///
/// class MainClass
/// {
/// static public void Main(string[] args)
/// {
/// ZipFile zFile = new ZipFile(args[0]);
/// Console.WriteLine("Listing of : " + zFile.Name);
/// Console.WriteLine("");
/// Console.WriteLine("Raw Size Size Date Time Name");
/// Console.WriteLine("-------- -------- -------- ------ ---------");
/// foreach (ZipEntry e in zFile) {
/// DateTime d = e.DateTime;
/// Console.WriteLine("{0, -10}{1, -10}{2} {3} {4}", e.Size, e.CompressedSize,
/// d.ToString("dd-MM-yy"), d.ToString("t"),
/// e.Name);
/// }
/// }
/// }
///
/// public class ZipFile : IEnumerable
{
string name;
string comment;
Stream baseStream;
ZipEntry[] entries;
///
/// Opens a Zip file with the given name for reading.
/// ///
/// An i/o error occurs
/// ///
/// The file doesn't contain a valid zip archive.
/// public ZipFile(string name) : this(File.OpenRead(name))
{
}
///
/// Opens a Zip file reading the given FileStream
/// ///
/// An i/o error occurs.
/// ///
/// The file doesn't contain a valid zip archive.
/// public ZipFile(FileStream file)
{
this.baseStream = file;
this.name = file.Name;
ReadEntries();
}
///
/// Opens a Zip file reading the given Stream
/// ///
/// An i/o error occurs
/// ///
/// The file doesn't contain a valid zip archive.
/// The stream provided cannot seek
/// public ZipFile(Stream baseStream)
{
this.baseStream = baseStream;
this.name = null;
ReadEntries();
}
///
/// Read an unsigned short in little endian byte order.
/// ///
/// An i/o error occurs.
/// ///
/// The file ends prematurely
/// int ReadLeShort()
{
return baseStream.ReadByte() | baseStream.ReadByte() << 8;
}
///
/// Read an int in little endian byte order.
/// ///
/// An i/o error occurs.
/// ///
/// The file ends prematurely
/// int ReadLeInt()
{
return ReadLeShort() | ReadLeShort() << 16;
}
///
/// Search for and read the central directory of a zip file filling the entries
/// array. This is called exactly once by the constructors.
/// ///
/// An i/o error occurs.
/// ///
/// The central directory is malformed or cannot be found
/// void ReadEntries()
{
// Search for the End Of Central Directory. When a zip comment is
// present the directory may start earlier.
//
// TODO: The search is limited to 64K which is the maximum size of a trailing comment field to aid speed.
// This should be compatible with both SFX and ZIP files but has only been tested for Zip files
// Need to confirm this is valid in all cases.
// Could also speed this up by reading memory in larger blocks?
if (baseStream.CanSeek == false) {
throw new ZipException("ZipFile stream must be seekable");
}
long pos = baseStream.Length - ZipConstants.ENDHDR;
if (pos <= 0) {
throw new ZipException("File is too small to be a Zip file");
}
long giveUpMarker = Math.Max(pos - 0x10000, 0);
do {
if (pos < giveUpMarker) {
throw new ZipException("central directory not found, probably not a zip file");
}
baseStream.Seek(pos--, SeekOrigin.Begin);
} while (ReadLeInt() != ZipConstants.ENDSIG);
int thisDiskNumber = ReadLeShort();
int startCentralDirDisk = ReadLeShort();
int entriesForThisDisk = ReadLeShort();
int entriesForWholeCentralDir = ReadLeShort();
int centralDirSize = ReadLeInt();
int offsetOfCentralDir = ReadLeInt();
int commentSize = ReadLeShort();
byte[] zipComment = new byte[commentSize];
baseStream.Read(zipComment, 0, zipComment.Length);
comment = ZipConstants.ConvertToString(zipComment);
/* Its seems possible that this is too strict, more digging required.
if (thisDiskNumber != 0 || startCentralDirDisk != 0 || entriesForThisDisk != entriesForWholeCentralDir) {
throw new ZipException("Spanned archives are not currently handled");
}
*/
entries = new ZipEntry[entriesForWholeCentralDir];
baseStream.Seek(offsetOfCentralDir, SeekOrigin.Begin);
for (int i = 0; i < entriesForWholeCentralDir; i++) {
if (ReadLeInt() != ZipConstants.CENSIG) {
throw new ZipException("Wrong Central Directory signature");
}
int versionMadeBy = ReadLeShort();
int versionToExtract = ReadLeShort();
int bitFlags = ReadLeShort();
int method = ReadLeShort();
int dostime = ReadLeInt();
int crc = ReadLeInt();
int csize = ReadLeInt();
int size = ReadLeInt();
int nameLen = ReadLeShort();
int extraLen = ReadLeShort();
int commentLen = ReadLeShort();
int diskStartNo = ReadLeShort(); // Not currently used
int internalAttributes = ReadLeShort(); // Not currently used
int externalAttributes = ReadLeInt();
int offset = ReadLeInt();
byte[] buffer = new byte[Math.Max(nameLen, commentLen)];
baseStream.Read(buffer, 0, nameLen);
string name = ZipConstants.ConvertToString(buffer, nameLen);
ZipEntry entry = new ZipEntry(name, versionToExtract, versionMadeBy);
entry.CompressionMethod = (CompressionMethod)method;
entry.Crc = crc & 0xffffffffL;
entry.Size = size & 0xffffffffL;
entry.CompressedSize = csize & 0xffffffffL;
entry.DosTime = (uint)dostime;
if (extraLen > 0) {
byte[] extra = new byte[extraLen];
baseStream.Read(extra, 0, extraLen);
entry.ExtraData = extra;
}
if (commentLen > 0) {
baseStream.Read(buffer, 0, commentLen);
entry.Comment = ZipConstants.ConvertToString(buffer, commentLen);
}
entry.ZipFileIndex = i;
entry.Offset = offset;
entry.ExternalFileAttributes = externalAttributes;
entries[i] = entry;
}
}
///
/// Closes the ZipFile. This also closes all input streams managed by
/// this class. Once closed, no further instance methods should be
/// called.
/// ///
/// An i/o error occurs.
/// public void Close()
{
entries = null;
lock(baseStream) {
baseStream.Close();
}
}
///
/// Returns an enumerator for the Zip entries in this Zip file.
/// ///
/// The Zip file has been closed.
/// public IEnumerator GetEnumerator()
{
if (entries == null) {
throw new InvalidOperationException("ZipFile has closed");
}
return new ZipEntryEnumeration(entries);
}
///
/// Return the index of the entry with a matching name
/// ///
Entry name to find
///
If true the comparison is case insensitive
///
The index position of the matching entry or -1 if not found ///
/// The Zip file has been closed.
/// public int FindEntry(string name, bool ignoreCase)
{
if (entries == null) {
throw new InvalidOperationException("ZipFile has been closed");
}
for (int i = 0; i < entries.Length; i++) {
if (string.Compare(name, entries[i].Name, ignoreCase) == 0) {
return i;
}
}
return -1;
}
///
/// Indexer property for ZipEntries
/// [System.Runtime.CompilerServices.IndexerNameAttribute("EntryByIndex")]
public ZipEntry this[int index] {
get {
return (ZipEntry) entries[index].Clone();
}
}
///
/// Searches for a zip entry in this archive with the given name.
/// String comparisons are case insensitive
/// ///
/// The name to find. May contain directory components separated by slashes ('/').
///
///
/// The zip entry, or null if no entry with that name exists.
/// ///
/// The Zip file has been closed.
/// public ZipEntry GetEntry(string name)
{
if (entries == null) {
throw new InvalidOperationException("ZipFile has been closed");
}
int index = FindEntry(name, true);
return index >= 0 ? (ZipEntry) entries[index].Clone() : null;
}
///
/// Checks, if the local header of the entry at index i matches the
/// central directory, and returns the offset to the data.
/// ///
/// The start offset of the (compressed) data.
/// ///
/// The stream ends prematurely
/// ///
/// The local header signature is invalid, the entry and central header file name lengths are different
/// or the local and entry compression methods dont match
/// long CheckLocalHeader(ZipEntry entry)
{
lock(baseStream) {
baseStream.Seek(entry.Offset, SeekOrigin.Begin);
if (ReadLeInt() != ZipConstants.LOCSIG) {
throw new ZipException("Wrong Local header signature");
}
short shortValue = (short)ReadLeShort(); // version required to extract
if (shortValue > ZipConstants.VERSION_MADE_BY) {
throw new ZipException(string.Format("Version required to extract this entry not supported ({0})", shortValue));
}
shortValue = (short)ReadLeShort(); // general purpose bit flags.
if ((shortValue & 0x30) != 0) {
throw new ZipException("The library doesnt support the zip version required to extract this entry");
}
if (entry.CompressionMethod != (CompressionMethod)ReadLeShort()) {
throw new ZipException("Compression method mismatch");
}
// Skip time, crc, size and csize
long oldPos = baseStream.Position;
baseStream.Position += ZipConstants.LOCNAM - ZipConstants.LOCTIM;
if (baseStream.Position - oldPos != ZipConstants.LOCNAM - ZipConstants.LOCTIM) {
throw new EndOfStreamException();
}
// TODO make test more correct... cant compare lengths as was done originally as this can fail for MBCS strings
int storedNameLength = ReadLeShort();
if (entry.Name.Length > storedNameLength) {
throw new ZipException("file name length mismatch");
}
int extraLen = storedNameLength + ReadLeShort();
return entry.Offset + ZipConstants.LOCHDR + extraLen;
}
}
///
/// Creates an input stream reading the given zip entry as
/// uncompressed data. Normally zip entry should be an entry
/// returned by GetEntry().
/// ///
/// the input stream.
/// ///
/// The ZipFile has already been closed
/// ///
/// The compression method for the entry is unknown
/// ///
/// The entry is not found in the ZipFile
/// public Stream GetInputStream(ZipEntry entry)
{
if (entries == null) {
throw new InvalidOperationException("ZipFile has closed");
}
int index = entry.ZipFileIndex;
if (index <>= entries.Length || entries[index].Name != entry.Name) {
index = FindEntry(entry.Name, true);
if (index < 0) {
throw new IndexOutOfRangeException();
}
}
return GetInputStream(index);
}
///
/// Creates an input stream reading the zip entry based on the index passed
/// ///
/// An input stream.
/// ///
/// The ZipFile has already been closed
/// ///
/// The compression method for the entry is unknown
/// ///
/// The entry is not found in the ZipFile
/// public Stream GetInputStream(int entryIndex)
{
if (entries == null) {
throw new InvalidOperationException("ZipFile has closed");
}
long start = CheckLocalHeader(entries[entryIndex]);
CompressionMethod method = entries[entryIndex].CompressionMethod;
Stream istr = new PartialInputStream(baseStream, start, entries[entryIndex].CompressedSize);
switch (method) {
case CompressionMethod.Stored:
return istr;
case CompressionMethod.Deflated:
return new InflaterInputStream(istr, new Inflater(true));
default:
throw new ZipException("Unknown compression method " + method);
}
}
///
/// Gets the comment for the zip file.
/// public string ZipFileComment {
get {
return comment;
}
}
///
/// Gets the name of this zip file.
/// public string Name {
get {
return name;
}
}
///
/// Gets the number of entries in this zip file.
/// ///
/// The Zip file has been closed.
/// public int Size {
get {
if (entries != null) {
return entries.Length;
} else {
throw new InvalidOperationException("ZipFile is closed");
}
}
}
class ZipEntryEnumeration : IEnumerator
{
ZipEntry[] array;
int ptr = -1;
public ZipEntryEnumeration(ZipEntry[] arr)
{
array = arr;
}
public object Current {
get {
return array[ptr];
}
}
public void Reset()
{
ptr = -1;
}
public bool MoveNext()
{
return (++ptr < array.Length);
}
}
class PartialInputStream : InflaterInputStream
{
Stream baseStream;
long filepos, end;
public PartialInputStream(Stream baseStream, long start, long len) : base(baseStream)
{
this.baseStream = baseStream;
filepos = start;
end = start + len;
}
public override int Available
{
get {
long amount = end - filepos;
if (amount > Int32.MaxValue) {
return Int32.MaxValue;
}
return (int) amount;
}
}
public override int ReadByte()
{
if (filepos == end) {
return -1; //ok
}
lock(baseStream) {
baseStream.Seek(filepos++, SeekOrigin.Begin);
return baseStream.ReadByte();
}
}
public override int Read(byte[] b, int off, int len)
{
if (len > end - filepos) {
len = (int) (end - filepos);
if (len == 0) {
return 0;
}
}
lock(baseStream) {
baseStream.Seek(filepos, SeekOrigin.Begin);
int count = baseStream.Read(b, off, len);
if (count > 0) {
filepos += len;
}
return count;
}
}
public long SkipBytes(long amount)
{
if (amount < 0) {
throw new ArgumentOutOfRangeException();
}
if (amount > end - filepos) {
amount = end - filepos;
}
filepos += amount;
return amount;
}
}
}
}
