ExOleObjStg.java
/* ====================================================================
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contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
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http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
==================================================================== */
package org.apache.poi.hslf.record;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.UncheckedIOException;
import java.util.Arrays;
import java.util.Map;
import java.util.function.Supplier;
import java.util.zip.DeflaterOutputStream;
import java.util.zip.InflaterInputStream;
import org.apache.commons.io.input.BoundedInputStream;
import org.apache.commons.io.input.UnsynchronizedByteArrayInputStream;
import org.apache.commons.io.output.UnsynchronizedByteArrayOutputStream;
import org.apache.poi.util.GenericRecordUtil;
import org.apache.poi.util.IOUtils;
import org.apache.poi.util.LittleEndian;
import org.apache.poi.util.RecordFormatException;
/**
* Storage for embedded OLE objects.
*/
public class ExOleObjStg extends PositionDependentRecordAtom implements PersistRecord {
//arbitrarily selected; may need to increase
private static final int DEFAULT_MAX_RECORD_LENGTH = 100_000_000;
private static int MAX_RECORD_LENGTH = DEFAULT_MAX_RECORD_LENGTH;
/**
* @param length the max record length allowed for ExOleObjStg
*/
public static void setMaxRecordLength(int length) {
MAX_RECORD_LENGTH = length;
}
/**
* @return the max record length allowed for ExOleObjStg
*/
public static int getMaxRecordLength() {
return MAX_RECORD_LENGTH;
}
private int _persistId; // Found from PersistPtrHolder
/**
* Record header.
*/
private final byte[] _header;
/**
* Record data.
*/
private byte[] _data;
/**
* Constructs a new empty storage container.
*/
public ExOleObjStg() {
_header = new byte[8];
_data = new byte[0];
LittleEndian.putShort(_header, 0, (short)0x10);
LittleEndian.putShort(_header, 2, (short)getRecordType());
LittleEndian.putInt(_header, 4, _data.length);
}
/**
* Constructs the link related atom record from its
* source data.
*
* @param source the source data as a byte array.
* @param start the start offset into the byte array.
* @param len the length of the slice in the byte array.
*/
protected ExOleObjStg(byte[] source, int start, int len) {
// Get the header.
_header = Arrays.copyOfRange(source, start, start+8);
// Get the record data.
_data = IOUtils.safelyClone(source, start+8, len-8, MAX_RECORD_LENGTH,
"ExOleObjStg.setMaxRecordLength()");
}
public boolean isCompressed() {
return LittleEndian.getShort(_header, 0)!=0;
}
/**
* Gets the uncompressed length of the data.
*
* @return the uncompressed length of the data.
*/
public int getDataLength() {
if (isCompressed()) {
return LittleEndian.getInt(_data, 0);
} else {
return _data.length;
}
}
/**
* Opens an input stream which will decompress the data on the fly.
*
* @return the data input stream.
* @throws RecordFormatException if the claimed uncompressed size exceeds the maximum allowed.
* @throws UncheckedIOException if the data size exceeds the expected size.
*/
public InputStream getData() {
if (isCompressed()) {
int size = LittleEndian.getInt(_data);
if (size < 0 || size > MAX_RECORD_LENGTH) {
throw new RecordFormatException(
"Claimed uncompressed data size (" + size + ") exceeds maximum allowed (" + MAX_RECORD_LENGTH + ")");
}
try {
InputStream compressedStream = UnsynchronizedByteArrayInputStream
.builder()
.setByteArray(_data)
.setOffset(4)
.get();
return BoundedInputStream.builder()
.setInputStream(new InflaterInputStream(compressedStream))
.setMaxCount(size)
.get();
} catch (IOException e) {
throw new UncheckedIOException(e);
}
} else {
try {
return UnsynchronizedByteArrayInputStream
.builder()
.setByteArray(_data)
.get();
} catch (IOException e) {
throw new UncheckedIOException(e);
}
}
}
public byte[] getRawData() {
return _data;
}
/**
* Sets the embedded data.
*
* @param data the embedded data.
*/
public void setData(byte[] data) throws IOException {
try (UnsynchronizedByteArrayOutputStream out = UnsynchronizedByteArrayOutputStream.builder().get();
DeflaterOutputStream def = new DeflaterOutputStream(out)) {
//first four bytes is the length of the raw data
byte[] b = new byte[4];
LittleEndian.putInt(b, 0, data.length);
out.write(b);
def.write(data, 0, data.length);
def.finish();
// TODO: CHECK if it's correct that DeflaterOutputStream is only finished and not closed?
_data = out.toByteArray();
LittleEndian.putInt(_header, 4, _data.length);
}
}
/**
* Gets the record type.
*
* @return the record type.
*/
@Override
public long getRecordType() {
return RecordTypes.ExOleObjStg.typeID;
}
/**
* Gets the record instance from the header
*
* @return record instance
*/
public int getRecordInstance() {
return (LittleEndian.getUShort(_header, 0) >>> 4);
}
/**
* Write the contents of the record back, so it can be written
* to disk.
*
* @param out the output stream to write to.
* @throws IOException if an error occurs.
*/
@Override
public void writeOut(OutputStream out) throws IOException {
out.write(_header);
out.write(_data);
}
/**
* Fetch our sheet ID, as found from a PersistPtrHolder.
* Should match the RefId of our matching SlidePersistAtom
*/
@Override
public int getPersistId() {
return _persistId;
}
/**
* Set our sheet ID, as found from a PersistPtrHolder
*/
@Override
public void setPersistId(int id) {
_persistId = id;
}
@Override
public void updateOtherRecordReferences(Map<Integer,Integer> oldToNewReferencesLookup) {
// nothing to update
}
@Override
public Map<String, Supplier<?>> getGenericProperties() {
return GenericRecordUtil.getGenericProperties(
"compressed", this::isCompressed,
"persistId", this::getPersistId,
"dataLength", this::getDataLength,
"data", this::getData
);
}
}