com.github.stephenc.javaisotools.loopfs.iso9660.Iso9660VolumeDescriptorSet Maven / Gradle / Ivy
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/*
* Copyright (c) 2010. Stephen Connolly.
* Copyright (c) 2006-2007. loopy project (http://loopy.sourceforge.net).
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
package com.github.stephenc.javaisotools.loopfs.iso9660;
import java.io.IOException;
import com.github.stephenc.javaisotools.loopfs.api.FileEntry;
import com.github.stephenc.javaisotools.loopfs.api.LoopFileSystemException;
import com.github.stephenc.javaisotools.loopfs.spi.VolumeDescriptorSet;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
public class Iso9660VolumeDescriptorSet implements VolumeDescriptorSet {
public static final int TYPE_BOOTRECORD = 0;
public static final int TYPE_PRIMARY_DESCRIPTOR = 1;
public static final int TYPE_SUPPLEMENTARY_DESCRIPTOR = 2;
public static final int TYPE_PARTITION_DESCRIPTOR = 3;
public static final int TYPE_TERMINATOR = 255;
private static final Log log = LogFactory.getLog(Iso9660VolumeDescriptorSet.class);
private final Iso9660FileSystem isoFile;
// common
private String systemIdentifier;
private String volumeSetIdentifier;
private String volumeIdentifier;
private String publisher;
private String preparer;
private String application;
private Iso9660FileEntry rootDirectoryEntry;
// primary
private String standardIdentifier;
private long totalBlocks;
private int volumeSetSize;
private int volumeSequenceNumber;
private long creationTime;
private long mostRecentModificationTime;
private long expirationTime;
private long effectiveTime;
private long pathTableSize;
private long locationOfLittleEndianPathTable;
private long locationOfOptionalLittleEndianPathTable;
private long locationOfBigEndianPathTable;
private long locationOfOptionalBigEndianPathTable;
// supplementary
public String encoding = Constants.DEFAULT_ENCODING;
public String escapeSequences;
private boolean hasPrimary = false;
private boolean hasSupplementary = false;
/**
* Initialize this instance.
*
* @param fileSystem the parent file system
*/
public Iso9660VolumeDescriptorSet(Iso9660FileSystem fileSystem) {
this.isoFile = fileSystem;
}
public boolean deserialize(byte[] descriptor) throws IOException {
final int type = Util.getUInt8(descriptor, 1);
boolean terminator = false;
switch (type) {
case TYPE_TERMINATOR:
if (!this.hasPrimary) {
throw new LoopFileSystemException("No primary volume descriptor found");
}
terminator = true;
break;
case TYPE_BOOTRECORD:
log.debug("Found boot record");
break;
case TYPE_PRIMARY_DESCRIPTOR:
log.debug("Found primary descriptor");
deserializePrimary(descriptor);
break;
case TYPE_SUPPLEMENTARY_DESCRIPTOR:
log.debug("Found supplementatory descriptor");
deserializeSupplementary(descriptor);
break;
case TYPE_PARTITION_DESCRIPTOR:
log.debug("Found partition descriptor");
break;
default:
log.debug("Found unknown descriptor with type " + type);
}
return terminator;
}
/**
* Read the fields of a primary volume descriptor.
*
* @param descriptor the descriptor bytes
* @throws IOException
*/
private void deserializePrimary(byte[] descriptor) throws IOException {
// according to the spec, some ISO 9660 file systems can contain multiple identical primary
// volume descriptors
if (this.hasPrimary) {
return;
}
validateBlockSize(descriptor);
if (!this.hasSupplementary) {
deserializeCommon(descriptor);
}
this.standardIdentifier = Util.getDChars(descriptor, 2, 5);
this.volumeSetSize = Util.getUInt16Both(descriptor, 121);
this.volumeSequenceNumber = Util.getUInt16Both(descriptor, 125);
this.totalBlocks = Util.getUInt32Both(descriptor, 81);
this.publisher = Util.getDChars(descriptor, 319, 128);
this.preparer = Util.getDChars(descriptor, 447, 128);
this.application = Util.getDChars(descriptor, 575, 128);
//this.copyrightFile = Descriptor.get(buffer, 703, 37)
//this.abstractFile = Descriptor.get(buffer, 740, 37)
//this.bibliographicalFile = Descriptor.get(buffer, 777, 37)
this.creationTime = Util.getStringDate(descriptor, 814);
this.mostRecentModificationTime = Util.getStringDate(descriptor, 831);
this.expirationTime = Util.getStringDate(descriptor, 848);
this.effectiveTime = Util.getStringDate(descriptor, 865);
this.pathTableSize = Util.getUInt32Both(descriptor, 133);
this.locationOfLittleEndianPathTable = Util.getUInt32LE(descriptor, 141);
this.locationOfOptionalLittleEndianPathTable = Util.getUInt32LE(descriptor, 145);
this.locationOfBigEndianPathTable = Util.getUInt32BE(descriptor, 149);
this.locationOfOptionalBigEndianPathTable = Util.getUInt32BE(descriptor, 153);
this.hasPrimary = true;
}
/**
* The supplementary descriptor sets the character encoding and may override the common
* descriptor information.
*
* @param descriptor the descriptor bytes
* @throws IOException
*/
private void deserializeSupplementary(byte[] descriptor) throws IOException {
// for now, only recognize one supplementary descriptor
if (this.hasSupplementary) {
return;
}
validateBlockSize(descriptor);
String escapeSequences = Util.getDChars(descriptor, 89, 32);
String enc = getEncoding(escapeSequences);
if (null != enc) {
this.encoding = enc;
this.escapeSequences = escapeSequences;
deserializeCommon(descriptor);
this.hasSupplementary = true;
} else {
log.warn("Unsupported encoding, escapeSequences: '" + this.escapeSequences + "'");
}
}
/**
* Read the information common to primary and secondary volume descriptors.
*
* @param descriptor the volume descriptor bytes
* @throws IOException
*/
private void deserializeCommon(byte[] descriptor) throws IOException {
this.systemIdentifier = Util.getAChars(descriptor, 9, 32, this.encoding);
this.volumeIdentifier = Util.getDChars(descriptor, 41, 32, this.encoding);
this.volumeSetIdentifier = Util.getDChars(descriptor, 191, 128, this.encoding);
this.rootDirectoryEntry = new Iso9660FileEntry(this.isoFile, descriptor, 157);
}
/**
* Check that the block size is what we expect.
*
* @param descriptor the descriptor bytes
* @throws IOException
*/
private void validateBlockSize(byte[] descriptor) throws IOException {
int blockSize = Util.getUInt16Both(descriptor, 129);
if (blockSize != Constants.DEFAULT_BLOCK_SIZE) {
throw new LoopFileSystemException("Invalid block size: " + blockSize);
}
}
/**
* Derive an encoding name from the given escape sequences.
*
* @param escapeSequences
* @return
*/
private String getEncoding(String escapeSequences) {
String encoding = null;
if (escapeSequences.equals("%/@")) {
// UCS-2 level 1
encoding = "UTF-16BE";
} else if (escapeSequences.equals("%/C")) {
// UCS-2 level 2
encoding = "UTF-16BE";
} else if (escapeSequences.equals("%/E")) {
// UCS-2 level 3
encoding = "UTF-16BE";
}
return encoding;
}
/**
* Returns true if the .iso file has one or more supplementary volume descriptors.
*
* @return
*/
public boolean hasSupplementary() {
return this.hasSupplementary;
}
public String getSystemIdentifier() {
return this.systemIdentifier;
}
public String getVolumeSetIdentifier() {
return this.volumeSetIdentifier;
}
public String getVolumeIdentifier() {
return this.volumeIdentifier;
}
public String getPublisher() {
return this.publisher;
}
public String getPreparer() {
return this.preparer;
}
public String getApplication() {
return this.application;
}
public Iso9660FileEntry getRootEntry() {
return this.rootDirectoryEntry;
}
public String getStandardIdentifier() {
return this.standardIdentifier;
}
public long getTotalBlocks() {
return this.totalBlocks;
}
public int getVolumeSetSize() {
return this.volumeSetSize;
}
public int getVolumeSequenceNumber() {
return this.volumeSequenceNumber;
}
public long getCreationTime() {
return this.creationTime;
}
public long getLastModifiedTime() {
return this.mostRecentModificationTime;
}
public long getExpirationTime() {
return this.expirationTime;
}
public long getEffectiveTime() {
return this.effectiveTime;
}
public long getPathTableSize() {
return this.pathTableSize;
}
public long getLocationOfLittleEndianPathTable() {
return this.locationOfLittleEndianPathTable;
}
public long getLocationOfOptionalLittleEndianPathTable() {
return this.locationOfOptionalLittleEndianPathTable;
}
public long getLocationOfBigEndianPathTable() {
return this.locationOfBigEndianPathTable;
}
public long getLocationOfOptionalBigEndianPathTable() {
return this.locationOfOptionalBigEndianPathTable;
}
/**
* Returns the character encoding.
*
* @return
*/
public String getEncoding() {
return this.encoding;
}
public String getEscapeSequences() {
return this.escapeSequences;
}
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