ZipInputStream.java
package sk.iway.iwcm.system.zip;
import java.io.EOFException;
import java.io.IOException;
/**
* ZipInputStream.java - modifikovany pre podporu diakritiky v nazvoch suborov
*
*@Title webjet4
*@Company Interway s.r.o. (www.interway.sk)
*@Copyright Interway s.r.o. (c) 2001-2005
*@author $Author: jeeff $
*@version $Revision: 1.3 $
*@created Date: 14.3.2005 13:25:34
*@modified $Date: 2007/09/07 13:39:29 $
*/
/*
* @(#)ZipInputStream.java 1.33 03/02/07
*
* Copyright 2003 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
import java.io.InputStream;
import java.io.PushbackInputStream;
import java.util.zip.CRC32;
import java.util.zip.Inflater;
import java.util.zip.ZipException;
/**
* This class implements an input stream filter for reading files in the ZIP
* file format. Includes support for both compressed and uncompressed entries.
*
* @author David Connelly
* @version 1.33, 02/07/03
*/
public class ZipInputStream extends sk.iway.iwcm.system.zip.InflaterInputStream implements sk.iway.iwcm.system.zip.ZipConstants
{
private ZipEntry entry;
private CRC32 crc = new CRC32();
private long remaining;
private byte[] tmpbuf = new byte[512];
private static final int STORED = ZipEntry.STORED;
private static final int DEFLATED = ZipEntry.DEFLATED;
private boolean closed = false;
// this flag is set to true after EOF has reached for
// one entry
private boolean entryEOF = false;
/**
* Check to make sure that this stream has not been closed
*/
private void ensureOpen() throws IOException
{
if (closed)
{
throw new IOException("Stream closed");
}
}
/**
* Creates a new ZIP input stream.
*
* @param in
* the actual input stream
*/
public ZipInputStream(InputStream in)
{
super(new PushbackInputStream(in, 512), new Inflater(true), 512);
usesDefaultInflater = true;
if (in == null)
{
throw new NullPointerException("in is null");
}
}
/**
* Reads the next ZIP file entry and positions stream at the beginning of the
* entry data.
*
* @return the ZipEntry just read
* @exception ZipException
* if a ZIP file error has occurred
* @exception IOException
* if an I/O error has occurred
*/
public ZipEntry getNextEntry() throws IOException
{
ensureOpen();
if (entry != null)
{
closeEntry();
}
crc.reset();
inf.reset();
if ((entry = readLOC()) == null)
{
return null;
}
if (entry.getMethod() == STORED)
{
remaining = entry.getSize();
}
entryEOF = false;
return entry;
}
/**
* Closes the current ZIP entry and positions the stream for reading the next
* entry.
*
* @exception ZipException
* if a ZIP file error has occurred
* @exception IOException
* if an I/O error has occurred
*/
public void closeEntry() throws IOException
{
ensureOpen();
while (read(tmpbuf, 0, tmpbuf.length) != -1);
entryEOF = true;
}
/**
* Returns 0 after EOF has reached for the current entry data, otherwise
* always return 1.
* <p>
* Programs should not count on this method to return the actual number of
* bytes that could be read without blocking.
*
* @return 1 before EOF and 0 after EOF has reached for current entry.
* @exception IOException
* if an I/O error occurs.
*
*/
@Override
public int available() throws IOException
{
ensureOpen();
if (entryEOF)
{
return 0;
}
else
{
return 1;
}
}
/**
* Reads from the current ZIP entry into an array of bytes. Blocks until some
* input is available.
*
* @param b
* the buffer into which the data is read
* @param off
* the start offset of the data
* @param len
* the maximum number of bytes read
* @return the actual number of bytes read, or -1 if the end of the entry is
* reached
* @exception ZipException
* if a ZIP file error has occurred
* @exception IOException
* if an I/O error has occurred
*/
@Override
public int read(byte[] b, int off, int len) throws IOException
{
ensureOpen();
if (off < 0 || len < 0 || off > b.length - len)
{
throw new IndexOutOfBoundsException();
}
else if (len == 0)
{
return 0;
}
if (entry == null)
{
return -1;
}
switch (entry.getMethod())
{
case DEFLATED :
len = super.read(b, off, len);
if (len == -1)
{
readEnd(entry);
entryEOF = true;
entry = null;
}
else
{
crc.update(b, off, len);
}
return len;
case STORED :
if (remaining <= 0)
{
entryEOF = true;
entry = null;
return -1;
}
if (len > remaining)
{
len = (int) remaining;
}
len = in.read(b, off, len);
if (len == -1)
{
throw new ZipException("unexpected EOF");
}
crc.update(b, off, len);
remaining -= len;
return len;
default :
throw new InternalError("invalid compression method");
}
}
/**
* Skips specified number of bytes in the current ZIP entry.
*
* @param n
* the number of bytes to skip
* @return the actual number of bytes skipped
* @exception ZipException
* if a ZIP file error has occurred
* @exception IOException
* if an I/O error has occurred
* @exception IllegalArgumentException
* if n < 0
*/
@Override
public long skip(long n) throws IOException
{
if (n < 0)
{
throw new IllegalArgumentException("negative skip length");
}
ensureOpen();
int max = (int) Math.min(n, Integer.MAX_VALUE);
int total = 0;
while (total < max)
{
int len = max - total;
if (len > tmpbuf.length)
{
len = tmpbuf.length;
}
len = read(tmpbuf, 0, len);
if (len == -1)
{
entryEOF = true;
break;
}
total += len;
}
return total;
}
/**
* Closes the ZIP input stream.
*
* @exception IOException
* if an I/O error has occurred
*/
@Override
public void close() throws IOException
{
if (!closed)
{
super.close();
closed = true;
}
}
private byte[] b = new byte[256];
/*
* Reads local file (LOC) header for next entry.
*/
private ZipEntry readLOC() throws IOException
{
try
{
readFully(tmpbuf, 0, LOCHDR);
}
catch (EOFException e)
{
return null;
}
if (get32(tmpbuf, 0) != LOCSIG)
{
return null;
}
// get the entry name and create the ZipEntry first
int len = get16(tmpbuf, LOCNAM);
if (len == 0)
{
throw new ZipException("missing entry name");
}
int blen = b.length;
if (len > blen)
{
do
blen = blen * 2;
while (len > blen);
b = new byte[blen];
}
readFully(b, 0, len);
//ZipEntry e = createZipEntry(getUTF8String(b, 0, len));
//WebJET - modified
String fileName = null;
try
{
fileName = getUTF8String(b, 0, len);
}
catch (Exception ex)
{
fileName = new String(b, 0, len, "Cp852");
}
fileName = fileName.trim();
ZipEntry e = createZipEntry(fileName);
// now get the remaining fields for the entry
e.version = get16(tmpbuf, LOCVER);
e.flag = get16(tmpbuf, LOCFLG);
if ((e.flag & 1) == 1)
{
throw new ZipException("encrypted ZIP entry not supported");
}
e.method = get16(tmpbuf, LOCHOW);
e.time = get32(tmpbuf, LOCTIM);
if ((e.flag & 8) == 8)
{
/* EXT descriptor present */
if (e.method != DEFLATED)
{
throw new ZipException("only DEFLATED entries can have EXT descriptor");
}
}
else
{
e.crc = get32(tmpbuf, LOCCRC);
e.csize = get32(tmpbuf, LOCSIZ);
e.size = get32(tmpbuf, LOCLEN);
}
len = get16(tmpbuf, LOCEXT);
if (len > 0)
{
byte[] bb = new byte[len];
readFully(bb, 0, len);
e.extra = bb;
}
return e;
}
/*
* Fetches a UTF8-encoded String from the specified byte array.
*/
private static String getUTF8String(byte[] b, int off, int len)
{
// First, count the number of characters in the sequence
int count = 0;
int max = off + len;
int i = off;
while (i < max)
{
int c = b[i++] & 0xff;
switch (c >> 4)
{
case 0 :
case 1 :
case 2 :
case 3 :
case 4 :
case 5 :
case 6 :
case 7 :
// 0xxxxxxx
count++;
break;
case 12 :
case 13 :
// 110xxxxx 10xxxxxx
if ((b[i++] & 0xc0) != 0x80)
{
throw new IllegalArgumentException();
}
count++;
break;
case 14 :
// 1110xxxx 10xxxxxx 10xxxxxx
if (((b[i++] & 0xc0) != 0x80) || ((b[i++] & 0xc0) != 0x80))
{
throw new IllegalArgumentException();
}
count++;
break;
default :
// 10xxxxxx, 1111xxxx
throw new IllegalArgumentException();
}
}
if (i != max)
{
throw new IllegalArgumentException();
}
// Now decode the characters...
char[] cs = new char[count];
i = 0;
while (off < max)
{
int c = b[off++] & 0xff;
switch (c >> 4)
{
case 0 :
case 1 :
case 2 :
case 3 :
case 4 :
case 5 :
case 6 :
case 7 :
// 0xxxxxxx
cs[i++] = (char) c;
break;
case 12 :
case 13 :
// 110xxxxx 10xxxxxx
cs[i++] = (char) (((c & 0x1f) << 6) | (b[off++] & 0x3f));
break;
case 14 :
// 1110xxxx 10xxxxxx 10xxxxxx
int t = (b[off++] & 0x3f) << 6;
cs[i++] = (char) (((c & 0x0f) << 12) | t | (b[off++] & 0x3f));
break;
default :
// 10xxxxxx, 1111xxxx
throw new IllegalArgumentException();
}
}
return new String(cs, 0, count);
}
/**
* Creates a new <code>ZipEntry</code> object for the specified entry name.
*
* @param name
* the ZIP file entry name
* @return the ZipEntry just created
*/
protected ZipEntry createZipEntry(String name)
{
return new ZipEntry(name);
}
/*
* Reads end of deflated entry as well as EXT descriptor if present.
*/
private void readEnd(ZipEntry e) throws IOException
{
int n = inf.getRemaining();
if (n > 0)
{
((PushbackInputStream) in).unread(buf, len - n, n);
}
if ((e.flag & 8) == 8)
{
/* EXT descriptor present */
readFully(tmpbuf, 0, EXTHDR);
long sig = get32(tmpbuf, 0);
if (sig != EXTSIG)
{ // no EXTSIG present
e.crc = sig;
e.csize = get32(tmpbuf, EXTSIZ - EXTCRC);
e.size = get32(tmpbuf, EXTLEN - EXTCRC);
((PushbackInputStream) in).unread(tmpbuf, EXTHDR - EXTCRC - 1, EXTCRC);
}
else
{
e.crc = get32(tmpbuf, EXTCRC);
e.csize = get32(tmpbuf, EXTSIZ);
e.size = get32(tmpbuf, EXTLEN);
}
}
if (e.size != inf.getTotalOut())
{
throw new ZipException("invalid entry size (expected " + e.size + " but got " + inf.getTotalOut() + " bytes)");
}
if (e.csize != inf.getTotalIn())
{
throw new ZipException("invalid entry compressed size (expected " + e.csize + " but got " + inf.getTotalIn() + " bytes)");
}
if (e.crc != crc.getValue())
{
throw new ZipException("invalid entry CRC (expected 0x" + Long.toHexString(e.crc) + " but got 0x"
+ Long.toHexString(crc.getValue()) + ")");
}
}
/*
* Reads bytes, blocking until all bytes are read.
*/
private void readFully(byte[] b, int off, int len) throws IOException
{
while (len > 0)
{
int n = in.read(b, off, len);
if (n == -1)
{
throw new EOFException();
}
off += n;
len -= n;
}
}
/*
* Fetches unsigned 16-bit value from byte array at specified offset. The
* bytes are assumed to be in Intel (little-endian) byte order.
*/
private static final int get16(byte b[], int off)
{
return (b[off] & 0xff) | ((b[off + 1] & 0xff) << 8);
}
/*
* Fetches unsigned 32-bit value from byte array at specified offset. The
* bytes are assumed to be in Intel (little-endian) byte order.
*/
private static final long get32(byte b[], int off)
{
return get16(b, off) | ((long) get16(b, off + 2) << 16);
}
}