added Tar task + implementation classes

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@267597 13f79535-47bb-0310-9956-ffa450edef68
26 years ago · bf94e2fb09
--- a/bootstrap.bat
+++ b/bootstrap.bat
@@ -2,7 +2,7 @@
 echo BOOTSTRAPPING ANT DISTRIBUTION
 set C=%CLASSPATH%;lib/xml.jar
 set SRCDIR=src\main\org\apache\tools\ant
 set SRCDIR=src\main\org\apache\tools
 set TMPDIR=tmp
 if "%OS%" == "Windows_NT" goto nt
@@ -18,14 +18,18 @@ mkdir %TMPDIR%
 echo ** COMPILING ANT CLASSES
 rem Compile the classes into the temp directory
 javac -classpath "%C%" -d %TMPDIR% %SRCDIR%\*.java
 rem Reset classpath to include base ant class files
 set C=%TMPDIR%;%C%
 rem Compile sub classes into the temp directory
 javac -classpath "%C%" -d %TMPDIR% %SRCDIR%\taskdefs\*.java
 javac -classpath "%C%" -d %TMPDIR% %SRCDIR%\tar\*.java
 rem Compile the classes into the temp directory
 javac -classpath "%C%" -d %TMPDIR% %SRCDIR%\ant\*.java
 rem Compile sub classes into the temp directory
 javac -classpath "%C%" -d %TMPDIR% %SRCDIR%\ant\taskdefs\*.java
 echo ** COPYING REQUIRED FILES
--- a/bootstrap.sh
+++ b/bootstrap.sh
@@ -2,7 +2,7 @@ if [ -f $HOME/.antrc ] ; then
  . $HOME/.antrc
 fi
 SRCDIR=src/main/org/apache/tools/ant
 SRCDIR=src/main/org/apache/tools
 CLASSDIR=classes
 CLASSPATH=${CLASSPATH}:${JAVA_HOME}/lib/classes.zip:${JAVA_HOME}/lib/tools.jar
 CLASSPATH=${CLASSPATH}:lib/xml.jar:src/main:${CLASSDIR}
@@ -12,8 +12,9 @@ mkdir -p ${CLASSDIR}
 export CLASSPATH
 echo $CLASSPATH
 javac  -d ${CLASSDIR} ${SRCDIR}/*.java
 javac  -d ${CLASSDIR} ${SRCDIR}/taskdefs/*.java
 javac  -d ${CLASSDIR} ${SRCDIR}/tar/*.java
 javac  -d ${CLASSDIR} ${SRCDIR}/ant/*.java
 javac  -d ${CLASSDIR} ${SRCDIR}/ant/taskdefs/*.java
 cp src/main/org/apache/tools/ant/taskdefs/defaults.properties ${CLASSDIR}/org/apache/tools/ant/taskdefs
 cp src/main/org/apache/tools/ant/parser.properties ${CLASSDIR}/org/apache/tools/ant
--- a/build.xml
+++ b/build.xml
@@ -7,6 +7,7 @@
 <project name="Ant" default="main" basedir=".">
  <target name="init">
    <property name="Name" value="Ant"/>
    <property name="name" value="ant"/>
    <property name="version" value="1.0-rc1"/>
@@ -22,7 +23,7 @@
    <property name="dist.dir" value="../dist/ant"/>
    <property name="classpath" value="lib/xml.jar"/>
    <property name="packages" value="org.apache.tools.ant.*"/>
    <property name="packages" value="org.apache.tools.*"/>
    <property name="manifest" value="src/etc/manifest"/>
    <property name="build.compiler" value="classic"/>
@@ -79,9 +80,8 @@
             destdir="${build.javadocs}"
             author="true"
             version="true"
             use="true"
             windowtitle="${name} API"
             doctitle="${name}"
             windowtitle="${Name} API"
             doctitle="${Name}"
             bottom="Copyright &#169; 2000 Apache Software Foundation. All Rights Reserved."
    />
  </target>
@@ -111,10 +111,23 @@
     <copyfile src="README" dest="${dist.dir}/README"/>
     <copyfile src="TODO" dest="${dist.dir}/TODO"/>
     <copyfile src="LICENSE" dest="${dist.dir}/LICENSE"/>
  </target>
     <jar jarfile="${name}.jar" basedir="${dist.dir}" includes="**"/>     
  <!-- =================================================================== -->
  <!-- Packages the distribution with ZIP                                  -->
  <!-- =================================================================== -->
  <target name="dist-zip" depends="dist">
    <zip zipfile="${Name}-${version}.zip" basedir="${dist.dir}" includes="**"/>
  </target>
  <!-- =================================================================== -->
  <!-- Packages the distribution with TAR-GZIP                             -->
  <!-- =================================================================== -->
  <target name="dist-tgz" depends="dist">
    <tar tarfile="${Name}-${version}.tar" basedir="${dist.dir}" includes="**"/>
    <gzip zipfile="${Name}-${version}.tar.gz" src="${Name}-${version}.tar"/>
  </target>
  <!-- =================================================================== -->
  <!-- Cleans up generated stuff                                           -->
  <!-- =================================================================== -->
--- a/src/main/org/apache/tools/ant/taskdefs/Tar.java
+++ b/src/main/org/apache/tools/ant/taskdefs/Tar.java
@@ -0,0 +1,139 @@
 /*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights 
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:  
 *       "This product includes software developed by the 
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written 
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */
 package org.apache.tools.ant.taskdefs;
 import java.io.*;
 import org.apache.tools.ant.*;
 import org.apache.tools.tar.*;
 /**
 * Creates a TAR archive.
 *
 * @author Stefano Mazzocchi <a href="mailto:stefano@apache.org">stefano@apache.org</a>
 */
 public class Tar extends MatchingTask {
    File tarFile;
    File baseDir;
    /**
     * This is the name/location of where to create the tar file.
     */
    public void setTarfile(String tarFilename) {
        tarFile = project.resolveFile(tarFilename);
    }
    /**
     * This is the base directory to look in for things to tar.
     */
    public void setBasedir(String baseDirname) {
        baseDir = project.resolveFile(baseDirname);
    }
    public void execute() throws BuildException {
        project.log("Building tar: "+ tarFile.getAbsolutePath());
        if (baseDir == null) {
            throw new BuildException("basedir attribute must be set!");
        }
        if (!baseDir.exists()) {
            throw new BuildException("basedir does not exist!");
        }
        DirectoryScanner ds = super.getDirectoryScanner(baseDir);
        String[] files = ds.getIncludedFiles();
        try {
            TarOutputStream tOut = new TarOutputStream(new FileOutputStream(tarFile));
            tOut.setDebug(true);
            for (int i = 0; i < files.length; i++) {
                File f = new File(baseDir,files[i]);
                String name = files[i].replace(File.separatorChar,'/');
                tarFile(f, tOut, name);
            }
            // close up
            tOut.close();
        } catch (IOException ioe) {
            String msg = "Problem creating TAR: " + ioe.getMessage();
            throw new BuildException(msg);
        }
    }
    protected void tarFile(File file, TarOutputStream tOut, String vPath)
        throws IOException
    {
        FileInputStream fIn = new FileInputStream(file);
        TarEntry te = new TarEntry(vPath);
        te.setSize(file.length());
        te.setModTime(file.lastModified() / 1000);
        tOut.putNextEntry(te);
        byte[] buffer = new byte[8 * 1024];
        int count = 0;
        do {
            tOut.write(buffer, 0, count);
            count = fIn.read(buffer, 0, buffer.length);
        } while (count != -1);
        tOut.closeEntry();        
        fIn.close();
    }
 }
--- a/src/main/org/apache/tools/ant/taskdefs/Zip.java
+++ b/src/main/org/apache/tools/ant/taskdefs/Zip.java
@@ -76,16 +76,17 @@ public class Zip extends MatchingTask {
    protected String archiveType = "zip";
    /**
        This is the name/location of where to 
        create the .zip file.
    */
     * This is the name/location of where to 
     * create the .zip file.
     */
    public void setZipfile(String zipFilename) {
        zipFile = project.resolveFile(zipFilename);
    }
    /**
        This is the base directory to look in for 
        things to zip.
    */
     * This is the base directory to look in for 
     * things to zip.
     */
    public void setBasedir(String baseDirname) {
        baseDir = project.resolveFile(baseDirname);
    }
--- a/src/main/org/apache/tools/ant/taskdefs/defaults.properties
+++ b/src/main/org/apache/tools/ant/taskdefs/defaults.properties
@@ -22,5 +22,6 @@ property=org.apache.tools.ant.taskdefs.Property
 taskdef=org.apache.tools.ant.taskdefs.Taskdef
 ant=org.apache.tools.ant.taskdefs.Ant
 exec=org.apache.tools.ant.taskdefs.Exec
 tar=org.apache.tools.ant.taskdefs.Tar
 # remove the task below once everyone has migrated
 javadoc2=org.apache.tools.ant.taskdefs.Javadoc
--- a/src/main/org/apache/tools/tar/TarBuffer.java
+++ b/src/main/org/apache/tools/tar/TarBuffer.java
@@ -0,0 +1,440 @@
 /*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */
 /*
 * This package is based on the work done by Timothy Gerard Endres 
 * (time@ice.com) to whom the Ant project is very grateful for his great code.
 */
 package org.apache.tools.tar;
 import java.io.*;
 /**
 * The TarBuffer class implements the tar archive concept
 * of a buffered input stream. This concept goes back to the
 * days of blocked tape drives and special io devices. In the
 * Java universe, the only real function that this class
 * performs is to ensure that files have the correct "block"
 * size, or other tars will complain.
 * <p>
 * You should never have a need to access this class directly.
 * TarBuffers are created by Tar IO Streams.
 * 
 * @author Timothy Gerard Endres <a href="mailto:time@ice.com">time@ice.com</a>
 */
 public class TarBuffer {
    public static final int DEFAULT_RCDSIZE = (512);
    public static final int DEFAULT_BLKSIZE = (DEFAULT_RCDSIZE * 20);
    private InputStream     inStream;
    private OutputStream    outStream;
    private byte[]          blockBuffer;
    private int             currBlkIdx;
    private int             currRecIdx;
    private int             blockSize;
    private int             recordSize;
    private int             recsPerBlock;
    private boolean         debug;
    public TarBuffer(InputStream inStream) {
        this(inStream, TarBuffer.DEFAULT_BLKSIZE);
    }
    public TarBuffer(InputStream inStream, int blockSize) {
        this(inStream, blockSize, TarBuffer.DEFAULT_RCDSIZE);
    }
    public TarBuffer(InputStream inStream, int blockSize, int recordSize) {
        this.inStream = inStream;
        this.outStream = null;
        this.initialize(blockSize, recordSize);
    }
    public TarBuffer(OutputStream outStream) {
        this(outStream, TarBuffer.DEFAULT_BLKSIZE);
    }
    public TarBuffer(OutputStream outStream, int blockSize) {
        this(outStream, blockSize, TarBuffer.DEFAULT_RCDSIZE);
    }
    public TarBuffer(OutputStream outStream, int blockSize, int recordSize) {
        this.inStream = null;
        this.outStream = outStream;
        this.initialize(blockSize, recordSize);
    }
    /**
     * Initialization common to all constructors.
     */
    private void initialize(int blockSize, int recordSize) {
        this.debug = false;
        this.blockSize = blockSize;
        this.recordSize = recordSize;
        this.recsPerBlock = (this.blockSize / this.recordSize);
        this.blockBuffer = new byte[this.blockSize];
        if (this.inStream != null) {
            this.currBlkIdx = -1;
            this.currRecIdx = this.recsPerBlock;
        } else {
            this.currBlkIdx = 0;
            this.currRecIdx = 0;
        } 
    } 
    /**
     * Get the TAR Buffer's block size. Blocks consist of multiple records.
     */
    public int getBlockSize() {
        return this.blockSize;
    } 
    /**
     * Get the TAR Buffer's record size.
     */
    public int getRecordSize() {
        return this.recordSize;
    } 
    /**
     * Set the debugging flag for the buffer.
     * 
     * @param debug If true, print debugging output.
     */
    public void setDebug(boolean debug) {
        this.debug = debug;
    } 
    /**
     * Determine if an archive record indicate End of Archive. End of
     * archive is indicated by a record that consists entirely of null bytes.
     * 
     * @param record The record data to check.
     */
    public boolean isEOFRecord(byte[] record) {
        for (int i = 0, sz = this.getRecordSize(); i < sz; ++i) {
            if (record[i] != 0) {
                return false;
            } 
        }
        return true;
    } 
    /**
     * Skip over a record on the input stream.
     */
    public void skipRecord() throws IOException {
        if (this.debug) {
            System.err.println("SkipRecord: recIdx = " + this.currRecIdx 
                               + " blkIdx = " + this.currBlkIdx);
        } 
        if (this.inStream == null) {
            throw new IOException("reading (via skip) from an output buffer");
        } 
        if (this.currRecIdx >= this.recsPerBlock) {
            if (!this.readBlock()) {
                return;    // UNDONE
            } 
        } 
        this.currRecIdx++;
    } 
    /**
     * Read a record from the input stream and return the data.
     * 
     * @return The record data.
     */
    public byte[] readRecord() throws IOException {
        if (this.debug) {
            System.err.println("ReadRecord: recIdx = " + this.currRecIdx 
                               + " blkIdx = " + this.currBlkIdx);
        } 
        if (this.inStream == null) {
            throw new IOException("reading from an output buffer");
        } 
        if (this.currRecIdx >= this.recsPerBlock) {
            if (!this.readBlock()) {
                return null;
            } 
        } 
        byte[] result = new byte[this.recordSize];
        System.arraycopy(this.blockBuffer, 
                         (this.currRecIdx * this.recordSize), result, 0, 
                         this.recordSize);
        this.currRecIdx++;
        return result;
    } 
    /**
     * @return false if End-Of-File, else true
     */
    private boolean readBlock() throws IOException {
        if (this.debug) {
            System.err.println("ReadBlock: blkIdx = " + this.currBlkIdx);
        } 
        if (this.inStream == null) {
            throw new IOException("reading from an output buffer");
        } 
        this.currRecIdx = 0;
        int offset = 0;
        int bytesNeeded = this.blockSize;
        while (bytesNeeded > 0) {
            long numBytes = this.inStream.read(this.blockBuffer, offset, 
                                               bytesNeeded);
            // 
            // NOTE
            // We have fit EOF, and the block is not full!
            // 
            // This is a broken archive. It does not follow the standard
            // blocking algorithm. However, because we are generous, and
            // it requires little effort, we will simply ignore the error
            // and continue as if the entire block were read. This does
            // not appear to break anything upstream. We used to return
            // false in this case.
            // 
            // Thanks to 'Yohann.Roussel@alcatel.fr' for this fix.
            // 
            if (numBytes == -1) {
                break;
            } 
            offset += numBytes;
            bytesNeeded -= numBytes;
            if (numBytes != this.blockSize) {
                if (this.debug) {
                    System.err.println("ReadBlock: INCOMPLETE READ " 
                                       + numBytes + " of " + this.blockSize 
                                       + " bytes read.");
                } 
            } 
        } 
        this.currBlkIdx++;
        return true;
    } 
    /**
     * Get the current block number, zero based.
     * 
     * @return The current zero based block number.
     */
    public int getCurrentBlockNum() {
        return this.currBlkIdx;
    } 
    /**
     * Get the current record number, within the current block, zero based.
     * Thus, current offset = (currentBlockNum * recsPerBlk) + currentRecNum.
     * 
     * @return The current zero based record number.
     */
    public int getCurrentRecordNum() {
        return this.currRecIdx - 1;
    } 
    /**
     * Write an archive record to the archive.
     * 
     * @param record The record data to write to the archive.
     */
    public void writeRecord(byte[] record) throws IOException {
        if (this.debug) {
            System.err.println("WriteRecord: recIdx = " + this.currRecIdx 
                               + " blkIdx = " + this.currBlkIdx);
        } 
        if (this.outStream == null) {
            throw new IOException("writing to an input buffer");
        } 
        if (record.length != this.recordSize) {
            throw new IOException("record to write has length '" 
                                  + record.length 
                                  + "' which is not the record size of '" 
                                  + this.recordSize + "'");
        } 
        if (this.currRecIdx >= this.recsPerBlock) {
            this.writeBlock();
        } 
        System.arraycopy(record, 0, this.blockBuffer, 
                         (this.currRecIdx * this.recordSize), 
                         this.recordSize);
        this.currRecIdx++;
    } 
    /**
     * Write an archive record to the archive, where the record may be
     * inside of a larger array buffer. The buffer must be "offset plus
     * record size" long.
     * 
     * @param buf The buffer containing the record data to write.
     * @param offset The offset of the record data within buf.
     */
    public void writeRecord(byte[] buf, int offset) throws IOException {
        if (this.debug) {
            System.err.println("WriteRecord: recIdx = " + this.currRecIdx 
                               + " blkIdx = " + this.currBlkIdx);
        } 
        if (this.outStream == null) {
            throw new IOException("writing to an input buffer");
        } 
        if ((offset + this.recordSize) > buf.length) {
            throw new IOException("record has length '" + buf.length 
                                  + "' with offset '" + offset 
                                  + "' which is less than the record size of '" 
                                  + this.recordSize + "'");
        } 
        if (this.currRecIdx >= this.recsPerBlock) {
            this.writeBlock();
        } 
        System.arraycopy(buf, offset, this.blockBuffer, 
                         (this.currRecIdx * this.recordSize), 
                         this.recordSize);
        this.currRecIdx++;
    } 
    /**
     * Write a TarBuffer block to the archive.
     */
    private void writeBlock() throws IOException {
        if (this.debug) {
            System.err.println("WriteBlock: blkIdx = " + this.currBlkIdx);
        } 
        if (this.outStream == null) {
            throw new IOException("writing to an input buffer");
        } 
        this.outStream.write(this.blockBuffer, 0, this.blockSize);
        this.outStream.flush();
        this.currRecIdx = 0;
        this.currBlkIdx++;
    } 
    /**
     * Flush the current data block if it has any data in it.
     */
    private void flushBlock() throws IOException {
        if (this.debug) {
            System.err.println("TarBuffer.flushBlock() called.");
        } 
        if (this.outStream == null) {
            throw new IOException("writing to an input buffer");
        } 
        if (this.currRecIdx > 0) {
            this.writeBlock();
        } 
    } 
    /**
     * Close the TarBuffer. If this is an output buffer, also flush the
     * current block before closing.
     */
    public void close() throws IOException {
        if (this.debug) {
            System.err.println("TarBuffer.closeBuffer().");
        } 
        if (this.outStream != null) {
            this.flushBlock();
            if (this.outStream != System.out 
                    && this.outStream != System.err) {
                this.outStream.close();
                this.outStream = null;
            } 
        } else if (this.inStream != null) {
            if (this.inStream != System.in) {
                this.inStream.close();
                this.inStream = null;
            } 
        } 
    } 
 }
--- a/src/main/org/apache/tools/tar/TarConstants.java
+++ b/src/main/org/apache/tools/tar/TarConstants.java
@@ -0,0 +1,182 @@
 /*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights 
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:  
 *       "This product includes software developed by the 
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written 
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */
 /*
 * This package is based on the work done by Timothy Gerard Endres 
 * (time@ice.com) to whom the Ant project is very grateful for his great code.
 */
 package org.apache.tools.tar;
 /**
 * This interface contains all the definitions used in the package.
 *
 * @author Timothy Gerard Endres <a href="mailto:time@ice.com">time@ice.com</a>
 * @author Stefano Mazzocchi <a href="mailto:stefano@apache.org">stefano@apache.org</a>
 */
 public interface TarConstants {
    /**
     * The length of the name field in a header buffer.
     */
    public static final int    NAMELEN = 100;
    /**
     * The length of the mode field in a header buffer.
     */
    public static final int    MODELEN = 8;
    /**
     * The length of the user id field in a header buffer.
     */
    public static final int    UIDLEN = 8;
    /**
     * The length of the group id field in a header buffer.
     */
    public static final int    GIDLEN = 8;
    /**
     * The length of the checksum field in a header buffer.
     */
    public static final int    CHKSUMLEN = 8;
    /**
     * The length of the size field in a header buffer.
     */
    public static final int    SIZELEN = 12;
    /**
     * The length of the magic field in a header buffer.
     */
    public static final int    MAGICLEN = 8;
    /**
     * The length of the modification time field in a header buffer.
     */
    public static final int    MODTIMELEN = 12;
    /**
     * The length of the user name field in a header buffer.
     */
    public static final int    UNAMELEN = 32;
    /**
     * The length of the group name field in a header buffer.
     */
    public static final int    GNAMELEN = 32;
    /**
     * The length of the devices field in a header buffer.
     */
    public static final int    DEVLEN = 8;
    /**
     * LF_ constants represent the "link flag" of an entry, or more commonly,
     * the "entry type". This is the "old way" of indicating a normal file.
     */
    public static final byte   LF_OLDNORM = 0;
    /**
     * Normal file type.
     */
    public static final byte   LF_NORMAL = (byte) '0';
    /**
     * Link file type.
     */
    public static final byte   LF_LINK = (byte) '1';
    /**
     * Symbolic link file type.
     */
    public static final byte   LF_SYMLINK = (byte) '2';
    /**
     * Character device file type.
     */
    public static final byte   LF_CHR = (byte) '3';
    /**
     * Block device file type.
     */
    public static final byte   LF_BLK = (byte) '4';
    /**
     * Directory file type.
     */
    public static final byte   LF_DIR = (byte) '5';
    /**
     * FIFO (pipe) file type.
     */
    public static final byte   LF_FIFO = (byte) '6';
    /**
     * Contiguous file type.
     */
    public static final byte   LF_CONTIG = (byte) '7';
    /**
     * The magic tag representing a POSIX tar archive.
     */
    public static final String TMAGIC = "ustar";
    /**
     * The magic tag representing a GNU tar archive.
     */
    public static final String GNU_TMAGIC = "ustar  ";
 }
--- a/src/main/org/apache/tools/tar/TarEntry.java
+++ b/src/main/org/apache/tools/tar/TarEntry.java
@@ -0,0 +1,572 @@
 /*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */
 /*
 * This package is based on the work done by Timothy Gerard Endres 
 * (time@ice.com) to whom the Ant project is very grateful for his great code.
 */
 package org.apache.tools.tar;
 import java.io.*;
 import java.util.*;
 /**
 * This class represents an entry in a Tar archive. It consists
 * of the entry's header, as well as the entry's File. Entries
 * can be instantiated in one of three ways, depending on how
 * they are to be used.
 * <p>
 * TarEntries that are created from the header bytes read from
 * an archive are instantiated with the TarEntry( byte[] )
 * constructor. These entries will be used when extracting from
 * or listing the contents of an archive. These entries have their
 * header filled in using the header bytes. They also set the File
 * to null, since they reference an archive entry not a file.
 * <p>
 * TarEntries that are created from Files that are to be written
 * into an archive are instantiated with the TarEntry( File )
 * constructor. These entries have their header filled in using
 * the File's information. They also keep a reference to the File
 * for convenience when writing entries.
 * <p>
 * Finally, TarEntries can be constructed from nothing but a name.
 * This allows the programmer to construct the entry by hand, for
 * instance when only an InputStream is available for writing to
 * the archive, and the header information is constructed from
 * other information. In this case the header fields are set to
 * defaults and the File is set to null.
 * 
 * <p>
 * The C structure for a Tar Entry's header is:
 * <pre>
 * struct header {
 * char name[NAMSIZ];
 * char mode[8];
 * char uid[8];
 * char gid[8];
 * char size[12];
 * char mtime[12];
 * char chksum[8];
 * char linkflag;
 * char linkname[NAMSIZ];
 * char magic[8];
 * char uname[TUNMLEN];
 * char gname[TGNMLEN];
 * char devmajor[8];
 * char devminor[8];
 * } header;
 * </pre>
 * 
 * @author Timothy Gerard Endres <a href="mailto:time@ice.com">time@ice.com</a>
 * @author Stefano Mazzocchi <a href="mailto:stefano@apache.org">stefano@apache.org</a>
 */
 public class TarEntry implements TarConstants {
    private StringBuffer name;      /** The entry's name. */
    private int          mode;      /** The entry's permission mode. */
    private int          userId;    /** The entry's user id. */
    private int          groupId;   /** The entry's group id. */
    private long         size;      /** The entry's size. */
    private long         modTime;   /** The entry's modification time. */
    private int          checkSum;  /** The entry's checksum. */
    private byte         linkFlag;  /** The entry's link flag. */
    private StringBuffer linkName;  /** The entry's link name. */
    private StringBuffer magic;     /** The entry's magic tag. */
    private StringBuffer userName;  /** The entry's user name. */
    private StringBuffer groupName; /** The entry's group name. */
    private int          devMajor;  /** The entry's major device number. */
    private int          devMinor;  /** The entry's minor device number. */
    private File         file;      /** The entry's file reference */ 
    /** 
     * Construct an empty entry and prepares the header values.
     */ 
    private TarEntry () {
        this.magic = new StringBuffer(TMAGIC);
        this.name = new StringBuffer();
        this.linkName = new StringBuffer();
        String user = System.getProperty("user.name", "");
        if (user.length() > 31) {
            user = user.substring(0, 31);
        } 
        this.userId = 0;
        this.groupId = 0;
        this.userName = new StringBuffer(user);
        this.groupName = new StringBuffer("");
        this.file = null;
    }
    /** 
     * Construct an entry with only a name. This allows the programmer
     * to construct the entry's header "by hand". File is set to null.
     */ 
    public TarEntry(String name) {
        this();
        boolean isDir = name.endsWith("/");
        this.checkSum = 0;
        this.devMajor = 0;
        this.devMinor = 0;
        this.name = new StringBuffer(name);
        this.mode = isDir ? 040755 : 0100644;
        this.linkFlag = isDir ? LF_DIR : LF_NORMAL;
        this.userId = 0;
        this.groupId = 0;
        this.size = 0;
        this.checkSum = 0;
        this.modTime = (new Date()).getTime() / 1000;
        this.linkName = new StringBuffer("");
        this.userName = new StringBuffer("");
        this.groupName = new StringBuffer("");
        this.devMajor = 0;
        this.devMinor = 0;
    }   
    /** 
     * Construct an entry for a file. File is set to file, and the
     * header is constructed from information from the file.
     *  
     * @param file The file that the entry represents.
     */ 
    public TarEntry(File file) {
        this();
        this.file = file;
        String name = file.getPath();
        String osname = System.getProperty("os.name");
        if (osname != null) {
            // Strip off drive letters!
            // REVIEW Would a better check be "(File.separator == '\')"?
            String Win32Prefix = "Windows";
            String prefix = osname.substring(0, Win32Prefix.length());
            if (prefix.equalsIgnoreCase(Win32Prefix)) {
                if (name.length() > 2) {
                    char ch1 = name.charAt(0);
                    char ch2 = name.charAt(1);
                    if (ch2 == ':' 
                            && ((ch1 >= 'a' && ch1 <= 'z') 
                                || (ch1 >= 'A' && ch1 <= 'Z'))) {
                        name = name.substring(2);
                    } 
                } 
            } 
        } 
        name = name.replace(File.separatorChar, '/');
        // No absolute pathnames
        // Windows (and Posix?) paths can start with "\\NetworkDrive\",
        // so we loop on starting /'s.
        while (name.startsWith("/")) {
            name = name.substring(1);
        }
        this.linkName = new StringBuffer("");
        this.name = new StringBuffer(name);
        if (file.isDirectory()) {
            this.mode = 040755;
            this.linkFlag = LF_DIR;
            if (this.name.charAt(this.name.length() - 1) != '/') {
                this.name.append("/");
            } 
        } else {
            this.mode = 0100644;
            this.linkFlag = LF_NORMAL;
        } 
        if (this.name.length() > NAMELEN) {
            throw new RuntimeException("file name '" + this.name 
                                             + "' is too long ( > " 
                                             + NAMELEN + " bytes)");
            // UNDONE When File lets us get the userName, use it!
        } 
        this.size = file.length();
        this.modTime = file.lastModified() / 1000;
        this.checkSum = 0;
        this.devMajor = 0;
        this.devMinor = 0;
    }   
    /** 
     * Construct an entry from an archive's header bytes. File is set
     * to null.
     *  
     * @param headerBuf The header bytes from a tar archive entry.
     */ 
    public TarEntry(byte[] headerBuf) {
        this();
        this.parseTarHeader(headerBuf);
    }   
    /** 
     * Determine if the two entries are equal. Equality is determined
     * by the header names being equal.
     *  
     * @return it Entry to be checked for equality.
     * @return True if the entries are equal.
     */ 
    public boolean equals(TarEntry it) {
        return this.getName().equals(it.getName());
    }   
    /** 
     * Determine if the given entry is a descendant of this entry.
     * Descendancy is determined by the name of the descendant
     * starting with this entry's name.
     *  
     * @param desc Entry to be checked as a descendent of this.
     * @return True if entry is a descendant of this.
     */ 
    public boolean isDescendent(TarEntry desc) {
        return desc.getName().startsWith(this.getName());
    }   
    /** 
     * Get this entry's name.
     *  
     * @return This entry's name.
     */ 
    public String getName() {
        return this.name.toString();
    }   
    /** 
     * Set this entry's name.
     *  
     * @param name This entry's new name.
     */ 
    public void setName(String name) {
        this.name = new StringBuffer(name);
    }   
    /** 
     * Get this entry's user id.
     *  
     * @return This entry's user id.
     */ 
    public int getUserId() {
        return this.userId;
    }   
    /** 
     * Set this entry's user id.
     *  
     * @param userId This entry's new user id.
     */ 
    public void setUserId(int userId) {
        this.userId = userId;
    }   
    /** 
     * Get this entry's group id.
     *  
     * @return This entry's group id.
     */ 
    public int getGroupId() {
        return this.groupId;
    }   
    /** 
     * Set this entry's group id.
     *  
     * @param groupId This entry's new group id.
     */ 
    public void setGroupId(int groupId) {
        this.groupId = groupId;
    }   
    /** 
     * Get this entry's user name.
     *  
     * @return This entry's user name.
     */ 
    public String getUserName() {
        return this.userName.toString();
    }   
    /** 
     * Set this entry's user name.
     *  
     * @param userName This entry's new user name.
     */ 
    public void setUserName(String userName) {
        this.userName = new StringBuffer(userName);
    }   
    /** 
     * Get this entry's group name.
     *  
     * @return This entry's group name.
     */ 
    public String getGroupName() {
        return this.groupName.toString();
    }   
    /** 
     * Set this entry's group name.
     *  
     * @param groupName This entry's new group name.
     */ 
    public void setGroupName(String groupName) {
        this.groupName = new StringBuffer(groupName);
    }   
    /** 
     * Convenience method to set this entry's group and user ids.
     *  
     * @param userId This entry's new user id.
     * @param groupId This entry's new group id.
     */ 
    public void setIds(int userId, int groupId) {
        this.setUserId(userId);
        this.setGroupId(groupId);
    }   
    /** 
     * Convenience method to set this entry's group and user names.
     *  
     * @param userName This entry's new user name.
     * @param groupName This entry's new group name.
     */ 
    public void setNames(String userName, String groupName) {
        this.setUserName(userName);
        this.setGroupName(groupName);
    }   
    /** 
     * Set this entry's modification time. The parameter passed
     * to this method is in "Java time".
     *  
     * @param time This entry's new modification time.
     */ 
    public void setModTime(long time) {
        this.modTime = time / 1000;
    }   
    /** 
     * Set this entry's modification time.
     *  
     * @param time This entry's new modification time.
     */ 
    public void setModTime(Date time) {
        this.modTime = time.getTime() / 1000;
    }   
    /** 
     * Set this entry's modification time.
     *  
     * @param time This entry's new modification time.
     */ 
    public Date getModTime() {
        return new Date(this.modTime * 1000);
    }   
    /** 
     * Get this entry's file.
     *  
     * @return This entry's file.
     */ 
    public File getFile() {
        return this.file;
    }   
    /** 
     * Get this entry's file size.
     *  
     * @return This entry's file size.
     */ 
    public long getSize() {
        return this.size;
    }   
    /** 
     * Set this entry's file size.
     *  
     * @param size This entry's new file size.
     */ 
    public void setSize(long size) {
        this.size = size;
    }   
    /** 
     * Return whether or not this entry represents a directory.
     *  
     * @return True if this entry is a directory.
     */ 
    public boolean isDirectory() {
        if (this.file != null) {
            return this.file.isDirectory();
        } 
        if (this.linkFlag == LF_DIR) {
            return true;
        } 
        if (this.getName().endsWith("/")) {
            return true;
        } 
        return false;
    }   
    /** 
     * If this entry represents a file, and the file is a directory, return
     * an array of TarEntries for this entry's children.
     *  
     * @return An array of TarEntry's for this entry's children.
     */ 
    public TarEntry[] getDirectoryEntries() {
        if (this.file == null ||!this.file.isDirectory()) {
            return new TarEntry[0];
        } 
        String[]   list = this.file.list();
        TarEntry[] result = new TarEntry[list.length];
        for (int i = 0; i < list.length; ++i) {
            result[i] = new TarEntry(new File(this.file, list[i]));
        } 
        return result;
    }   
    /** 
     * Write an entry's header information to a header buffer.
     *  
     * @param outbuf The tar entry header buffer to fill in.
     */ 
    public void writeEntryHeader(byte[] outbuf) {
        int offset = 0;
        offset = TarUtils.getNameBytes(this.name, outbuf, offset, NAMELEN);
        offset = TarUtils.getOctalBytes(this.mode, outbuf, offset, MODELEN);
        offset = TarUtils.getOctalBytes(this.userId, outbuf, offset, UIDLEN);
        offset = TarUtils.getOctalBytes(this.groupId, outbuf, offset, GIDLEN);
        offset = TarUtils.getLongOctalBytes(this.size, outbuf, offset, SIZELEN);
        offset = TarUtils.getLongOctalBytes(this.modTime, outbuf, offset, MODTIMELEN);
        int csOffset = offset;
        for (int c = 0; c < CHKSUMLEN; ++c) {
            outbuf[offset++] = (byte) ' ';
        }
        outbuf[offset++] = this.linkFlag;
        offset = TarUtils.getNameBytes(this.linkName, outbuf, offset, NAMELEN);
        offset = TarUtils.getNameBytes(this.magic, outbuf, offset, MAGICLEN);
        offset = TarUtils.getNameBytes(this.userName, outbuf, offset, UNAMELEN);
        offset = TarUtils.getNameBytes(this.groupName, outbuf, offset, GNAMELEN);
        offset = TarUtils.getOctalBytes(this.devMajor, outbuf, offset, DEVLEN);
        offset = TarUtils.getOctalBytes(this.devMinor, outbuf, offset, DEVLEN);
        while (offset < outbuf.length) {
            outbuf[offset++] = 0;
        }
        long checkSum = TarUtils.computeCheckSum(outbuf);
        TarUtils.getCheckSumOctalBytes(checkSum, outbuf, csOffset, CHKSUMLEN);
    }   
    /** 
     * Parse an entry's header information from a header buffer.
     *  
     * @param header The tar entry header buffer to get information from.
     */ 
    public void parseTarHeader(byte[] header) {
        int offset = 0;
        this.name = TarUtils.parseName(header, offset, NAMELEN);  
        offset += NAMELEN;
        this.mode = (int) TarUtils.parseOctal(header, offset, MODELEN); 
        offset += MODELEN;
        this.userId = (int) TarUtils.parseOctal(header, offset, UIDLEN);
        offset += UIDLEN;
        this.groupId = (int) TarUtils.parseOctal(header, offset, GIDLEN);
        offset += GIDLEN;
        this.size = TarUtils.parseOctal(header, offset, SIZELEN);
        offset += SIZELEN;
        this.modTime = TarUtils.parseOctal(header, offset, MODTIMELEN);
        offset += MODTIMELEN;
        this.checkSum = (int) TarUtils.parseOctal(header, offset, CHKSUMLEN);
        offset += CHKSUMLEN;
        this.linkFlag = header[offset++];
        this.linkName = TarUtils.parseName(header, offset, NAMELEN);
        offset += NAMELEN;
        this.magic = TarUtils.parseName(header, offset, MAGICLEN);
        offset += MAGICLEN;
        this.userName = TarUtils.parseName(header, offset, UNAMELEN);
        offset += UNAMELEN;
        this.groupName = TarUtils.parseName(header, offset, GNAMELEN);
        offset += GNAMELEN;
        this.devMajor = (int) TarUtils.parseOctal(header, offset, DEVLEN);
        offset += DEVLEN;
        this.devMinor = (int) TarUtils.parseOctal(header, offset, DEVLEN);
    }        
 }       
--- a/src/main/org/apache/tools/tar/TarInputStream.java
+++ b/src/main/org/apache/tools/tar/TarInputStream.java
@@ -0,0 +1,419 @@
 /*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */
 /*
 * This package is based on the work done by Timothy Gerard Endres 
 * (time@ice.com) to whom the Ant project is very grateful for his great code.
 */
 package org.apache.tools.tar;
 import java.io.*;
 /**
 * The TarInputStream reads a UNIX tar archive as an InputStream.
 * methods are provided to position at each successive entry in
 * the archive, and the read each entry as a normal input stream
 * using read().
 * 
 * @author Timothy Gerard Endres <a href="mailto:time@ice.com">time@ice.com</a>
 * @author Stefano Mazzocchi <a href="mailto:stefano@apache.org">stefano@apache.org</a>
 */
 public class TarInputStream extends FilterInputStream {
    protected boolean      debug;
    protected boolean      hasHitEOF;
    protected int          entrySize;
    protected int          entryOffset;
    protected byte[]       oneBuf;
    protected byte[]       readBuf;
    protected TarBuffer    buffer;
    protected TarEntry     currEntry;
    public TarInputStream(InputStream is) {
        this(is, TarBuffer.DEFAULT_BLKSIZE, TarBuffer.DEFAULT_RCDSIZE);
    }
    public TarInputStream(InputStream is, int blockSize) {
        this(is, blockSize, TarBuffer.DEFAULT_RCDSIZE);
    }
    public TarInputStream(InputStream is, int blockSize, int recordSize) {
        super(is);
        this.buffer = new TarBuffer(is, blockSize, recordSize);
        this.readBuf = null;
        this.oneBuf = new byte[1];
        this.debug = false;
        this.hasHitEOF = false;
    }
    /**
     * Sets the debugging flag.
     * 
     * @param debugF True to turn on debugging.
     */
    public void setDebug(boolean debug) {
        this.debug = debug;
        this.buffer.setDebug(debug);
    } 
    /**
     * Closes this stream. Calls the TarBuffer's close() method.
     */
    public void close() throws IOException {
        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();
    } 
    /**
     * Get the available data that can be read from the current
     * entry in the archive. This does not indicate how much data
     * is left in the entire archive, only in the current entry.
     * This value is determined from the entry's size header field
     * and the amount of data already read from the current entry.
     * 
     * 
     * @return The number of available bytes for the current entry.
     */
    public int available() throws IOException {
        return this.entrySize - this.entryOffset;
    } 
    /**
     * Skip bytes in the input buffer. This skips bytes in the
     * current entry's data, not the entire archive, and will
     * stop at the end of the current entry's data if the number
     * to skip extends beyond that point.
     * 
     * @param numToSkip The number of bytes to skip.
     */
    public void skip(int numToSkip) throws IOException {
        // REVIEW
        // This is horribly inefficient, but it ensures that we
        // properly skip over bytes via the TarBuffer...
        // 
        byte[] skipBuf = new byte[8 * 1024];
        for (int num = numToSkip; num > 0; ) {
            int numRead = this.read(skipBuf, 0, 
                                    (num > skipBuf.length ? skipBuf.length 
                                     : num));
            if (numRead == -1) {
                break;
            } 
            num -= numRead;
        } 
    } 
    /**
     * Since we do not support marking just yet, we return false.
     * 
     * @return False.
     */
    public boolean markSupported() {
        return false;
    } 
    /**
     * Since we do not support marking just yet, we do nothing.
     * 
     * @param markLimit The limit to mark.
     */
    public void mark(int markLimit) {}
    /**
     * Since we do not support marking just yet, we do nothing.
     */
    public void reset() {}
    /**
     * Get the next entry in this tar archive. This will skip
     * over any remaining data in the current entry, if there
     * is one, and place the input stream at the header of the
     * next entry, and read the header and instantiate a new
     * TarEntry from the header bytes and return that entry.
     * If there are no more entries in the archive, null will
     * be returned to indicate that the end of the archive has
     * been reached.
     * 
     * @return The next TarEntry in the archive, or null.
     */
    public TarEntry getNextEntry() throws IOException {
        if (this.hasHitEOF) {
            return null;
        } 
        if (this.currEntry != null) {
            int numToSkip = this.entrySize - this.entryOffset;
            if (this.debug) {
                System.err.println("TarInputStream: SKIP currENTRY '" 
                                   + this.currEntry.getName() + "' SZ " 
                                   + this.entrySize + " OFF " 
                                   + this.entryOffset + "  skipping " 
                                   + numToSkip + " bytes");
            } 
            if (numToSkip > 0) {
                this.skip(numToSkip);
            } 
            this.readBuf = null;
        } 
        byte[] headerBuf = this.buffer.readRecord();
        if (headerBuf == null) {
            if (this.debug) {
                System.err.println("READ NULL RECORD");
            } 
            this.hasHitEOF = true;
        } else if (this.buffer.isEOFRecord(headerBuf)) {
            if (this.debug) {
                System.err.println("READ EOF RECORD");
            } 
            this.hasHitEOF = true;
        } 
        if (this.hasHitEOF) {
            this.currEntry = null;
        } else {
            this.currEntry = new TarEntry(headerBuf);
            if (!(headerBuf[257] == 'u' && headerBuf[258] == 's' 
                    && headerBuf[259] == 't' && headerBuf[260] == 'a' 
                    && headerBuf[261] == 'r')) {
                this.entrySize = 0;
                this.entryOffset = 0;
                this.currEntry = null;
                throw new IOException("bad header in block " 
                                                 + this.buffer.getCurrentBlockNum() 
                                                 + " record " 
                                                 + this.buffer.getCurrentRecordNum() 
                                                 + ", " + 
                                       "header magic is not 'ustar', but '" 
                                                 + headerBuf[257] 
                                                 + headerBuf[258] 
                                                 + headerBuf[259] 
                                                 + headerBuf[260] 
                                                 + headerBuf[261] 
                                                 + "', or (dec) " 
                                                 + ((int) headerBuf[257]) 
                                                 + ", " 
                                                 + ((int) headerBuf[258]) 
                                                 + ", " 
                                                 + ((int) headerBuf[259]) 
                                                 + ", " 
                                                 + ((int) headerBuf[260]) 
                                                 + ", " 
                                                 + ((int) headerBuf[261]));
            } 
            if (this.debug) {
                System.err.println("TarInputStream: SET CURRENTRY '" 
                                   + this.currEntry.getName() 
                                   + "' size = " 
                                   + this.currEntry.getSize());
            } 
            this.entryOffset = 0;
            // REVIEW How do we resolve this discrepancy?!
            this.entrySize = (int) this.currEntry.getSize();
        } 
        return this.currEntry;
    } 
    /**
     * Reads a byte from the current tar archive entry.
     * 
     * This method simply calls read( byte[], int, int ).
     * 
     * @return The byte read, or -1 at EOF.
     */
    public int read() throws IOException {
        int num = this.read(this.oneBuf, 0, 1);
        if (num == -1) {
            return num;
        } else {
            return (int) this.oneBuf[0];
        }
    } 
    /**
     * Reads bytes from the current tar archive entry.
     * 
     * This method simply calls read( byte[], int, int ).
     * 
     * @param buf The buffer into which to place bytes read.
     * @return The number of bytes read, or -1 at EOF.
     */
    public int read(byte[] buf) throws IOException {
        return this.read(buf, 0, buf.length);
    } 
    /**
     * Reads bytes from the current tar archive entry.
     * 
     * This method is aware of the boundaries of the current
     * entry in the archive and will deal with them as if they
     * were this stream's start and EOF.
     * 
     * @param buf The buffer into which to place bytes read.
     * @param offset The offset at which to place bytes read.
     * @param numToRead The number of bytes to read.
     * @return The number of bytes read, or -1 at EOF.
     */
    public int read(byte[] buf, int offset, int numToRead) throws IOException {
        int totalRead = 0;
        if (this.entryOffset >= this.entrySize) {
            return -1;
        } 
        if ((numToRead + this.entryOffset) > this.entrySize) {
            numToRead = (this.entrySize - this.entryOffset);
        } 
        if (this.readBuf != null) {
            int sz = (numToRead > this.readBuf.length) ? this.readBuf.length 
                     : numToRead;
            System.arraycopy(this.readBuf, 0, buf, offset, sz);
            if (sz >= this.readBuf.length) {
                this.readBuf = null;
            } else {
                int    newLen = this.readBuf.length - sz;
                byte[] newBuf = new byte[newLen];
                System.arraycopy(this.readBuf, sz, newBuf, 0, newLen);
                this.readBuf = newBuf;
            } 
            totalRead += sz;
            numToRead -= sz;
            offset += sz;
        } 
        while (numToRead > 0) {
            byte[] rec = this.buffer.readRecord();
            if (rec == null) {
                // Unexpected EOF!
                throw new IOException("unexpected EOF with " + numToRead 
                                      + " bytes unread");
            } 
            int sz = numToRead;
            int recLen = rec.length;
            if (recLen > sz) {
                System.arraycopy(rec, 0, buf, offset, sz);
                this.readBuf = new byte[recLen - sz];
                System.arraycopy(rec, sz, this.readBuf, 0, recLen - sz);
            } else {
                sz = recLen;
                System.arraycopy(rec, 0, buf, offset, recLen);
            } 
            totalRead += sz;
            numToRead -= sz;
            offset += sz;
        } 
        this.entryOffset += totalRead;
        return totalRead;
    } 
    /**
     * Copies the contents of the current tar archive entry directly into
     * an output stream.
     * 
     * @param out The OutputStream into which to write the entry's data.
     */
    public void copyEntryContents(OutputStream out) throws IOException {
        byte[] buf = new byte[32 * 1024];
        while (true) {
            int numRead = this.read(buf, 0, buf.length);
            if (numRead == -1) {
                break;
            } 
            out.write(buf, 0, numRead);
        } 
    } 
 }
--- a/src/main/org/apache/tools/tar/TarOutputStream.java
+++ b/src/main/org/apache/tools/tar/TarOutputStream.java
@@ -0,0 +1,314 @@
 /*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */
 /*
 * This package is based on the work done by Timothy Gerard Endres 
 * (time@ice.com) to whom the Ant project is very grateful for his great code.
 */
 package org.apache.tools.tar;
 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().
 * 
 * @author Timothy Gerard Endres <a href="mailto:time@ice.com">time@ice.com</a>
 */
 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 {
        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 {
                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)
        // 
        while (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);
    } 
 }
--- a/src/main/org/apache/tools/tar/TarUtils.java
+++ b/src/main/org/apache/tools/tar/TarUtils.java
@@ -0,0 +1,234 @@
 /*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */
 /*
 * This package is based on the work done by Timothy Gerard Endres 
 * (time@ice.com) to whom the Ant project is very grateful for his great code.
 */
 package org.apache.tools.tar;
 /**
 * This class provides static utility methods to work with byte streams.
 * 
 * @author Timothy Gerard Endres <a href="mailto:time@ice.com">time@ice.com</a>
 * @author Stefano Mazzocchi <a href="mailto:stefano@apache.org">stefano@apache.org</a>
 */
 public class TarUtils {
    /**
     * Parse an octal string from a header buffer. This is used for the
     * file permission mode value.
     * 
     * @param header The header buffer from which to parse.
     * @param offset The offset into the buffer from which to parse.
     * @param length The number of header bytes to parse.
     * @return The long value of the octal string.
     */
    public static long parseOctal(byte[] header, int offset, int length) {
        long    result = 0;
        boolean stillPadding = true;
        int     end = offset + length;
        for (int i = offset; i < end; ++i) {
            if (header[i] == 0) {
                break;
            } 
            if (header[i] == (byte) ' ' || header[i] == '0') {
                if (stillPadding) {
                    continue;
                } 
                if (header[i] == (byte) ' ') {
                    break;
                } 
            } 
            stillPadding = false;
            result = (result << 3) + (header[i] - '0');
        } 
        return result;
    } 
    /**
     * Parse an entry name from a header buffer.
     * 
     * @param header The header buffer from which to parse.
     * @param offset The offset into the buffer from which to parse.
     * @param length The number of header bytes to parse.
     * @return The header's entry name.
     */
    public static StringBuffer parseName(byte[] header, int offset, int length) {
        StringBuffer result = new StringBuffer(length);
        int          end = offset + length;
        for (int i = offset; i < end; ++i) {
            if (header[i] == 0) {
                break;
            } 
            result.append((char) header[i]);
        } 
        return result;
    } 
    /**
     * Determine the number of bytes in an entry name.
     * 
     * @param header The header buffer from which to parse.
     * @param offset The offset into the buffer from which to parse.
     * @param length The number of header bytes to parse.
     * @return The number of bytes in a header's entry name.
     */
    public static int getNameBytes(StringBuffer name, byte[] buf, int offset, int length) {
        int i;
        for (i = 0; i < length && i < name.length(); ++i) {
            buf[offset + i] = (byte) name.charAt(i);
        } 
        for (; i < length; ++i) {
            buf[offset + i] = 0;
        } 
        return offset + length;
    } 
    /**
     * Parse an octal integer from a header buffer.
     * 
     * @param header The header buffer from which to parse.
     * @param offset The offset into the buffer from which to parse.
     * @param length The number of header bytes to parse.
     * @return The integer value of the octal bytes.
     */
    public static int getOctalBytes(long value, byte[] buf, int offset, int length) {
        byte[] result = new byte[length];
        int    idx = length - 1;
        buf[offset + idx] = 0;
        --idx;
        buf[offset + idx] = (byte) ' ';
        --idx;
        if (value == 0) {
            buf[offset + idx] = (byte) '0';
            --idx;
        } else {
            for (long val = value; idx >= 0 && val > 0; --idx) {
                buf[offset + idx] = (byte) ((byte) '0' + (byte) (val & 7));
                val = val >> 3;
            } 
        } 
        for (; idx >= 0; --idx) {
            buf[offset + idx] = (byte) ' ';
        } 
        return offset + length;
    } 
    /**
     * Parse an octal long integer from a header buffer.
     * 
     * @param header The header buffer from which to parse.
     * @param offset The offset into the buffer from which to parse.
     * @param length The number of header bytes to parse.
     * @return The long value of the octal bytes.
     */
    public static int getLongOctalBytes(long value, byte[] buf, int offset, int length) {
        byte[] temp = new byte[length + 1];
        getOctalBytes(value, temp, 0, length + 1);
        System.arraycopy(temp, 0, buf, offset, length);
        return offset + length;
    } 
    /**
     * Parse the checksum octal integer from a header buffer.
     * 
     * @param header The header buffer from which to parse.
     * @param offset The offset into the buffer from which to parse.
     * @param length The number of header bytes to parse.
     * @return The integer value of the entry's checksum.
     */
    public static int getCheckSumOctalBytes(long value, byte[] buf, int offset, int length) {
        getOctalBytes(value, buf, offset, length);
        buf[offset + length - 1] = (byte) ' ';
        buf[offset + length - 2] = 0;
        return offset + length;
    }
    /** 
     * Compute the checksum of a tar entry header.
     *  
     * @param buf The tar entry's header buffer.
     * @return The computed checksum.
     */ 
    public static long computeCheckSum(byte[] buf) {
        long sum = 0;
        for (int i = 0; i < buf.length; ++i) {
            sum += 255 & buf[i];
        } 
        return sum;
    }    
 }