/*
** Authored by Timothy Gerard Endres
** <mailto:[email protected]> <http://www.trustice.com>
**
** This work has been placed into the public domain.
** You may use this work in any way and for any purpose you wish.
**
** THIS SOFTWARE IS PROVIDED AS-IS WITHOUT WARRANTY OF ANY KIND,
** NOT EVEN THE IMPLIED WARRANTY OF MERCHANTABILITY. THE AUTHOR
** OF THIS SOFTWARE, ASSUMES _NO_ RESPONSIBILITY FOR ANY
** CONSEQUENCE RESULTING FROM THE USE, MODIFICATION, OR
** REDISTRIBUTION OF THIS SOFTWARE.
**
*/
package installer;
import java.io.*;
/**
* The TarOutputStream writes a UNIX tar archive as an OutputStream.
* Methods are provided to put entries, and then write their contents
* by writing to this stream using write().
*
*
* @version $Revision: 12504 $
* @author Timothy Gerard Endres,
* <a href="mailto:[email protected]">[email protected]</a>.
* @see TarBuffer
* @see TarHeader
* @see TarEntry
*/
public
class TarOutputStream
extends FilterOutputStream
{
protected boolean debug;
protected int currSize;
protected int currBytes;
protected byte[] oneBuf;
protected byte[] recordBuf;
protected int assemLen;
protected byte[] assemBuf;
protected TarBuffer buffer;
public
TarOutputStream( OutputStream os )
{
this( os, TarBuffer.DEFAULT_BLKSIZE, TarBuffer.DEFAULT_RCDSIZE );
}
public
TarOutputStream( OutputStream os, int blockSize )
{
this( os, blockSize, TarBuffer.DEFAULT_RCDSIZE );
}
public
TarOutputStream( OutputStream os, int blockSize, int recordSize )
{
super( os );
this.buffer = new TarBuffer( os, blockSize, recordSize );
this.debug = false;
this.assemLen = 0;
this.assemBuf = new byte[ recordSize ];
this.recordBuf = new byte[ recordSize ];
this.oneBuf = new byte[1];
}
/**
* Sets the debugging flag.
*
* @param debugF True to turn on debugging.
*/
public void
setDebug( boolean debugF )
{
this.debug = debugF;
}
/**
* Sets the debugging flag in this stream's TarBuffer.
*
* @param debugF True to turn on debugging.
*/
public void
setBufferDebug( boolean debug )
{
this.buffer.setDebug( debug );
}
/**
* Ends the TAR archive without closing the underlying OutputStream.
* The result is that the EOF record of nulls is written.
*/
public void
finish()
throws IOException
{
this.writeEOFRecord();
}
/**
* Ends the TAR archive and closes the underlying OutputStream.
* This means that finish() is called followed by calling the
* TarBuffer's close().
*/
public void
close()
throws IOException
{
this.finish();
this.buffer.close();
}
/**
* Get the record size being used by this stream's TarBuffer.
*
* @return The TarBuffer record size.
*/
public int
getRecordSize()
{
return this.buffer.getRecordSize();
}
/**
* Put an entry on the output stream. This writes the entry's
* header record and positions the output stream for writing
* the contents of the entry. Once this method is called, the
* stream is ready for calls to write() to write the entry's
* contents. Once the contents are written, closeEntry()
* <B>MUST</B> be called to ensure that all buffered data
* is completely written to the output stream.
*
* @param entry The TarEntry to be written to the archive.
*/
public void
putNextEntry( TarEntry entry )
throws IOException
{
if ( entry.getHeader().name.length() > TarHeader.NAMELEN )
throw new InvalidHeaderException
( "file name '" + entry.getHeader().name
+ "' is too long ( > "
+ TarHeader.NAMELEN + " bytes )" );
entry.writeEntryHeader( this.recordBuf );
this.buffer.writeRecord( this.recordBuf );
this.currBytes = 0;
if ( entry.isDirectory() )
this.currSize = 0;
else
this.currSize = (int)entry.getSize();
}
/**
* Close an entry. This method MUST be called for all file
* entries that contain data. The reason is that we must
* buffer data written to the stream in order to satisfy
* the buffer's record based writes. Thus, there may be
* data fragments still being assembled that must be written
* to the output stream before this entry is closed and the
* next entry written.
*/
public void
closeEntry()
throws IOException
{
if ( this.assemLen > 0 )
{
for ( int i = this.assemLen ; i < this.assemBuf.length ; ++i )
this.assemBuf[i] = 0;
this.buffer.writeRecord( this.assemBuf );
this.currBytes += this.assemLen;
this.assemLen = 0;
}
if ( this.currBytes < this.currSize )
throw new IOException
( "entry closed at '" + this.currBytes
+ "' before the '" + this.currSize
+ "' bytes specified in the header were written" );
}
/**
* Writes a byte to the current tar archive entry.
*
* This method simply calls read( byte[], int, int ).
*
* @param b The byte written.
*/
public void
write( int b )
throws IOException
{
this.oneBuf[0] = (byte) b;
this.write( this.oneBuf, 0, 1 );
}
/**
* Writes bytes to the current tar archive entry.
*
* This method simply calls read( byte[], int, int ).
*
* @param wBuf The buffer to write to the archive.
* @return The number of bytes read, or -1 at EOF.
*/
public void
write( byte[] wBuf )
throws IOException
{
this.write( wBuf, 0, wBuf.length );
}
/**
* Writes bytes to the current tar archive entry. This method
* is aware of the current entry and will throw an exception if
* you attempt to write bytes past the length specified for the
* current entry. The method is also (painfully) aware of the
* record buffering required by TarBuffer, and manages buffers
* that are not a multiple of recordsize in length, including
* assembling records from small buffers.
*
* This method simply calls read( byte[], int, int ).
*
* @param wBuf The buffer to write to the archive.
* @param wOffset The offset in the buffer from which to get bytes.
* @param numToWrite The number of bytes to write.
*/
public void
write( byte[] wBuf, int wOffset, int numToWrite )
throws IOException
{
if ( (this.currBytes + numToWrite) > this.currSize )
throw new IOException
( "request to write '" + numToWrite
+ "' bytes exceeds size in header of '"
+ this.currSize + "' bytes" );
//
// We have to deal with assembly!!!
// The programmer can be writing little 32 byte chunks for all
// we know, and we must assemble complete records for writing.
// REVIEW Maybe this should be in TarBuffer? Could that help to
// eliminate some of the buffer copying.
//
if ( this.assemLen > 0 )
{
if ( (this.assemLen + numToWrite ) >= this.recordBuf.length )
{
int aLen = this.recordBuf.length - this.assemLen;
System.arraycopy
( this.assemBuf, 0, this.recordBuf, 0, this.assemLen );
System.arraycopy
( wBuf, wOffset, this.recordBuf, this.assemLen, aLen );
this.buffer.writeRecord( this.recordBuf );
this.currBytes += this.recordBuf.length;
wOffset += aLen;
numToWrite -= aLen;
this.assemLen = 0;
}
else // ( (this.assemLen + numToWrite ) < this.recordBuf.length )
{
System.arraycopy
( wBuf, wOffset, this.assemBuf,
this.assemLen, numToWrite );
wOffset += numToWrite;
this.assemLen += numToWrite;
numToWrite -= numToWrite;
}
}
//
// When we get here we have EITHER:
// o An empty "assemble" buffer.
// o No bytes to write (numToWrite == 0)
//
for ( ; numToWrite > 0 ; )
{
if ( numToWrite < this.recordBuf.length )
{
System.arraycopy
( wBuf, wOffset, this.assemBuf, this.assemLen, numToWrite );
this.assemLen += numToWrite;
break;
}
this.buffer.writeRecord( wBuf, wOffset );
int num = this.recordBuf.length;
this.currBytes += num;
numToWrite -= num;
wOffset += num;
}
}
/**
* Write an EOF (end of archive) record to the tar archive.
* An EOF record consists of a record of all zeros.
*/
private void
writeEOFRecord()
throws IOException
{
for ( int i = 0 ; i < this.recordBuf.length ; ++i )
this.recordBuf[i] = 0;
this.buffer.writeRecord( this.recordBuf );
}
}
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