public ZipEntry(ZipEntry e, String name)
{
this.name = name;
known = e.known;
size = e.size;
compressedSize = e.compressedSize;
crc = e.crc;
dostime = e.dostime;
time = e.time;
method = e.method;
extra = e.extra;
comment = e.comment;
}
/**
* Creates an input stream reading the given zip entry as
* uncompressed data. Normally zip entry should be an entry
* returned by getEntry() or entries().
*
* This implementation returns null if the requested entry does not
* exist. This decision is not obviously correct, however, it does
* appear to mirror Sun's implementation, and it is consistant with
* their javadoc. On the other hand, the old JCL book, 2nd Edition,
* claims that this should return a "non-null ZIP entry". We have
* chosen for now ignore the old book, as modern versions of Ant (an
* important application) depend on this behaviour. See discussion
* in this thread:
* http://gcc.gnu.org/ml/java-patches/2004-q2/msg00602.html
*
* @param entry the entry to create an InputStream for.
* @return the input stream, or null if the requested entry does not exist.
*
* @exception IllegalStateException when the ZipFile has already been closed
* @exception IOException if a i/o error occured.
* @exception ZipException if the Zip archive is malformed.
*/
public Stream getInputStream(ZipEntry entry)
{
checkClosed();
Dictionary<String, ZipEntry> entries = getEntries();
String name = entry.getName();
ZipEntry zipEntry = entries[name];
if (zipEntry == null)
return null;
PartialInputStream inp = new PartialInputStream(raf, 1024);
inp.seek(zipEntry.offset);
if (inp.readLeInt() != LOCSIG)
throw new System.Exception("Wrong Local header signature: " + name);
inp.skip(4);
if (zipEntry.getMethod() != inp.readLeShort())
throw new System.Exception("Compression method mismatch: " + name);
inp.skip(16);
int nameLen = inp.readLeShort();
int extraLen = inp.readLeShort();
inp.skip(nameLen + extraLen);
inp.setLength(zipEntry.getCompressedSize());
int method = zipEntry.getMethod();
switch (method)
{
case ZipOutputStream.STORED:
return inp;
case ZipOutputStream.DEFLATED:
inp.addDummyByte();
return new System.IO.Compression.DeflateStream(inp, System.IO.Compression.CompressionMode.Decompress);
// Inflater inf = new Inflater(true);
//int sz = (int)entry.getSize();
//return new InflateStream(sz,inp,inf);
//return new InflaterInputStream(inp, inf)
//{
// public int available()
// {
// if (sz == -1)
// return super.available();
// if (super.available() != 0)
// return sz - inf.getTotalOut();
// return 0;
// }
//};
default:
throw new System.Exception("Unknown compression method " + method);
}
}
/**
* Creates a copy of the given zip entry.
* @param e the entry to copy.
*/
public ZipEntry(ZipEntry e) : this(e, e.name) { }
/**
* Read the central directory of a zip file and fill the entries
* array. This is called exactly once when first needed. It is called
* while holding the lock on <code>raf</code>.
*
* @exception IOException if a i/o error occured.
* @exception ZipException if the central directory is malformed
*/
private void readEntries()
{
/* Search for the End Of Central Directory. When a zip comment is
* present the directory may start earlier.
* Note that a comment has a maximum length of 64K, so that is the
* maximum we search backwards.
*/
PartialInputStream inp = new PartialInputStream(raf, 4096);
long pos = raf.Length - ENDHDR;
long top = Math.Max(0, pos - 65536);
do
{
if (pos < top)
throw new System.Exception
("central directory not found, probably not a zip file: " + name);
inp.seek(pos--);
}
while (inp.readLeInt() != ENDSIG);
if (inp.skip(ENDTOT - ENDNRD) != ENDTOT - ENDNRD)
throw new System.Exception(name);
int count = inp.readLeShort();
if (inp.skip(ENDOFF - ENDSIZ) != ENDOFF - ENDSIZ)
throw new System.Exception(name);
int centralOffset = inp.readLeInt();
entries = new Dictionary<String, ZipEntry>(count + count / 2);
inp.seek(centralOffset);
for (int i = 0; i < count; i++)
{
if (inp.readLeInt() != CENSIG)
throw new System.Exception("Wrong Central Directory signature: " + name);
inp.skip(6);
int method = inp.readLeShort();
int dostime = inp.readLeInt();
int crc = inp.readLeInt();
int csize = inp.readLeInt();
int size = inp.readLeInt();
int nameLen = inp.readLeShort();
int extraLen = inp.readLeShort();
int commentLen = inp.readLeShort();
inp.skip(8);
int offset = inp.readLeInt();
String _name = inp.readString(nameLen);
ZipEntry entry = new ZipEntry(_name);
entry.setMethod(method);
entry.setCrc(crc & 0xffffffffL);
entry.setSize(size & 0xffffffffL);
entry.setCompressedSize(csize & 0xffffffffL);
entry.setDOSTime(dostime);
if (extraLen > 0)
{
byte[] extra = new byte[extraLen];
inp.readFully(extra);
entry.setExtra(extra);
}
if (commentLen > 0)
{
entry.setComment(inp.readString(commentLen));
}
entry.offset = offset;
entries[_name] = entry;
}
}
