//
// Copyright (C) 2001 Mike Krueger
// Copyright (C) 2004 John Reilly
//
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.
///
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))
{
}
public ZipFile(FileStream file)
{
this.baseStream = file;
this.name = file.Name;
ReadEntries();
}
public ZipFile(Stream baseStream)
{
this.baseStream = baseStream;
this.name = null;
ReadEntries();
}
int ReadLeShort()
{
return baseStream.ReadByte() | baseStream.ReadByte() <<>
/
int ReadLeInt()
{
return ReadLeShort() | ReadLeShort()
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 < thisdisknumber =" ReadLeShort();" startcentraldirdisk =" ReadLeShort();" entriesforthisdisk =" ReadLeShort();" entriesforwholecentraldir =" ReadLeShort();" centraldirsize =" ReadLeInt();" offsetofcentraldir =" ReadLeInt();" commentsize =" ReadLeShort();" zipcomment =" new" comment =" ZipConstants.ConvertToString(zipComment);" entries =" new" i =" 0;" versionmadeby =" ReadLeShort();" versiontoextract =" ReadLeShort();" bitflags =" ReadLeShort();" method =" ReadLeShort();" dostime =" ReadLeInt();" crc =" ReadLeInt();" csize =" ReadLeInt();" size =" ReadLeInt();" namelen =" ReadLeShort();" extralen =" ReadLeShort();" commentlen =" ReadLeShort();" diskstartno =" ReadLeShort();" internalattributes =" ReadLeShort();" externalattributes =" ReadLeInt();" offset =" ReadLeInt();" buffer =" new" name =" ZipConstants.ConvertToString(buffer," entry =" new" compressionmethod =" (CompressionMethod)method;" crc =" crc" size =" size" compressedsize =" csize" dostime =" (uint)dostime;"> 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 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 <>
/// 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 <>
/// 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 < basestream =" baseStream;" filepos =" start;" end =" start" amount =" end"> 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 <> end - filepos) {
amount = end - filepos;
}
filepos += amount;
return amount;
}
}
}
}
