/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* 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
* the License. You may obtain a copy of the License at
*
* 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 java.util.zip;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;
import java.util.HashSet;
import libcore.util.EmptyArray;
/**
* Used to write (compress) data into zip files.
*
* <p>{@code ZipOutputStream} is used to write {@link ZipEntry}s to the underlying
* stream. Output from {@code ZipOutputStream} can be read using {@link ZipFile}
* or {@link ZipInputStream}.
*
* <p>While {@code DeflaterOutputStream} can write compressed zip file
* entries, this extension can write uncompressed entries as well.
* Use {@link ZipEntry#setMethod} or {@link #setMethod} with the {@link ZipEntry#STORED} flag.
*
* <h3>Example</h3>
* <p>Using {@code ZipOutputStream} is a little more complicated than {@link GZIPOutputStream}
* because zip files are containers that can contain multiple files. This code creates a zip
* file containing several files, similar to the {@code zip(1)} utility.
* <pre>
* OutputStream os = ...
* ZipOutputStream zos = new ZipOutputStream(new BufferedOutputStream(os));
* try {
* for (int i = 0; i < fileCount; ++i) {
* String filename = ...
* byte[] bytes = ...
* ZipEntry entry = new ZipEntry(filename);
* zos.putNextEntry(entry);
* zos.write(bytes);
* zos.closeEntry();
* }
* } finally {
* zos.close();
* }
* </pre>
*/
public class ZipOutputStream extends DeflaterOutputStream implements ZipConstants {
/**
* Indicates deflated entries.
*/
public static final int DEFLATED = 8;
/**
* Indicates uncompressed entries.
*/
public static final int STORED = 0;
private static final int ZIP_VERSION_2_0 = 20; // Zip specification version 2.0.
private byte[] commentBytes = EmptyArray.BYTE;
private final HashSet<String> entries = new HashSet<String>();
private int defaultCompressionMethod = DEFLATED;
private int compressionLevel = Deflater.DEFAULT_COMPRESSION;
private ByteArrayOutputStream cDir = new ByteArrayOutputStream();
private ZipEntry currentEntry;
private final CRC32 crc = new CRC32();
private int offset = 0, curOffset = 0;
/** The charset-encoded name for the current entry. */
private byte[] nameBytes;
/** The charset-encoded comment for the current entry. */
private byte[] entryCommentBytes;
/**
* Constructs a new {@code ZipOutputStream} that writes a zip file to the given
* {@code OutputStream}.
*
* <p>UTF-8 will be used to encode the file comment, entry names and comments.
*/
public ZipOutputStream(OutputStream os) {
super(os, new Deflater(Deflater.DEFAULT_COMPRESSION, true));
}
/**
* Closes the current {@code ZipEntry}, if any, and the underlying output
* stream. If the stream is already closed this method does nothing.
*
* @throws IOException
* If an error occurs closing the stream.
*/
@Override
public void close() throws IOException {
// don't call super.close() because that calls finish() conditionally
if (out != null) {
finish();
def.end();
out.close();
out = null;
}
}
/**
* Closes the current {@code ZipEntry}. Any entry terminal data is written
* to the underlying stream.
*
* @throws IOException
* If an error occurs closing the entry.
*/
public void closeEntry() throws IOException {
checkOpen();
if (currentEntry == null) {
return;
}
if (currentEntry.getMethod() == DEFLATED) {
super.finish();
}
// Verify values for STORED types
if (currentEntry.getMethod() == STORED) {
if (crc.getValue() != currentEntry.crc) {
throw new ZipException("CRC mismatch");
}
if (currentEntry.size != crc.tbytes) {
throw new ZipException("Size mismatch");
}
}
curOffset = LOCHDR;
// Write the DataDescriptor
if (currentEntry.getMethod() != STORED) {
curOffset += EXTHDR;
writeLong(out, EXTSIG);
writeLong(out, currentEntry.crc = crc.getValue());
writeLong(out, currentEntry.compressedSize = def.getTotalOut());
writeLong(out, currentEntry.size = def.getTotalIn());
}
// Update the CentralDirectory
// http://www.pkware.com/documents/casestudies/APPNOTE.TXT
int flags = currentEntry.getMethod() == STORED ? 0 : ZipFile.GPBF_DATA_DESCRIPTOR_FLAG;
// Since gingerbread, we always set the UTF-8 flag on individual files if appropriate.
// Some tools insist that the central directory have the UTF-8 flag.
// http://code.google.com/p/android/issues/detail?id=20214
flags |= ZipFile.GPBF_UTF8_FLAG;
writeLong(cDir, CENSIG);
writeShort(cDir, ZIP_VERSION_2_0); // Version this file was made by.
writeShort(cDir, ZIP_VERSION_2_0); // Minimum version needed to extract.
writeShort(cDir, flags);
writeShort(cDir, currentEntry.getMethod());
writeShort(cDir, currentEntry.time);
writeShort(cDir, currentEntry.modDate);
writeLong(cDir, crc.getValue());
if (currentEntry.getMethod() == DEFLATED) {
curOffset += writeLong(cDir, def.getTotalOut());
writeLong(cDir, def.getTotalIn());
} else {
curOffset += writeLong(cDir, crc.tbytes);
writeLong(cDir, crc.tbytes);
}
curOffset += writeShort(cDir, nameBytes.length);
if (currentEntry.extra != null) {
curOffset += writeShort(cDir, currentEntry.extra.length);
} else {
writeShort(cDir, 0);
}
writeShort(cDir, entryCommentBytes.length); // Comment length.
writeShort(cDir, 0); // Disk Start
writeShort(cDir, 0); // Internal File Attributes
writeLong(cDir, 0); // External File Attributes
writeLong(cDir, offset);
cDir.write(nameBytes);
nameBytes = null;
if (currentEntry.extra != null) {
cDir.write(currentEntry.extra);
}
offset += curOffset;
if (entryCommentBytes.length > 0) {
cDir.write(entryCommentBytes);
entryCommentBytes = EmptyArray.BYTE;
}
currentEntry = null;
crc.reset();
def.reset();
done = false;
}
/**
* Indicates that all entries have been written to the stream. Any terminal
* information is written to the underlying stream.
*
* @throws IOException
* if an error occurs while terminating the stream.
*/
@Override
public void finish() throws IOException {
// TODO: is there a bug here? why not checkOpen?
if (out == null) {
throw new IOException("Stream is closed");
}
if (cDir == null) {
return;
}
if (entries.isEmpty()) {
throw new ZipException("No entries");
}
if (currentEntry != null) {
closeEntry();
}
int cdirSize = cDir.size();
// Write Central Dir End
writeLong(cDir, ENDSIG);
writeShort(cDir, 0); // Disk Number
writeShort(cDir, 0); // Start Disk
writeShort(cDir, entries.size()); // Number of entries
writeShort(cDir, entries.size()); // Number of entries
writeLong(cDir, cdirSize); // Size of central dir
writeLong(cDir, offset); // Offset of central dir
writeShort(cDir, commentBytes.length);
if (commentBytes.length > 0) {
cDir.write(commentBytes);
}
// Write the central directory.
cDir.writeTo(out);
cDir = null;
}
/**
* Writes entry information to the underlying stream. Data associated with
* the entry can then be written using {@code write()}. After data is
* written {@code closeEntry()} must be called to complete the writing of
* the entry to the underlying stream.
*
* @param ze
* the {@code ZipEntry} to store.
* @throws IOException
* If an error occurs storing the entry.
* @see #write
*/
public void putNextEntry(ZipEntry ze) throws IOException {
if (currentEntry != null) {
closeEntry();
}
// Did this ZipEntry specify a method, or should we use the default?
int method = ze.getMethod();
if (method == -1) {
method = defaultCompressionMethod;
}
// If the method is STORED, check that the ZipEntry was configured appropriately.
if (method == STORED) {
if (ze.getCompressedSize() == -1) {
ze.setCompressedSize(ze.getSize());
} else if (ze.getSize() == -1) {
ze.setSize(ze.getCompressedSize());
}
if (ze.getCrc() == -1) {
throw new ZipException("STORED entry missing CRC");
}
if (ze.getSize() == -1) {
throw new ZipException("STORED entry missing size");
}
if (ze.size != ze.compressedSize) {
throw new ZipException("STORED entry size/compressed size mismatch");
}
}
checkOpen();
if (entries.contains(ze.name)) {
throw new ZipException("Entry already exists: " + ze.name);
}
if (entries.size() == 64*1024-1) {
// TODO: support Zip64.
throw new ZipException("Too many entries for the zip file format's 16-bit entry count");
}
nameBytes = ze.name.getBytes(StandardCharsets.UTF_8);
checkSizeIsWithinShort("Name", nameBytes);
entryCommentBytes = EmptyArray.BYTE;
if (ze.comment != null) {
entryCommentBytes = ze.comment.getBytes(StandardCharsets.UTF_8);
// The comment is not written out until the entry is finished, but it is validated here
// to fail-fast.
checkSizeIsWithinShort("Comment", entryCommentBytes);
}
def.setLevel(compressionLevel);
ze.setMethod(method);
currentEntry = ze;
entries.add(currentEntry.name);
// Local file header.
// http://www.pkware.com/documents/casestudies/APPNOTE.TXT
int flags = (method == STORED) ? 0 : ZipFile.GPBF_DATA_DESCRIPTOR_FLAG;
// Java always outputs UTF-8 filenames. (Before Java 7, the RI didn't set this flag and used
// modified UTF-8. From Java 7, when using UTF_8 it sets this flag and uses normal UTF-8.)
flags |= ZipFile.GPBF_UTF8_FLAG;
writeLong(out, LOCSIG); // Entry header
writeShort(out, ZIP_VERSION_2_0); // Minimum version needed to extract.
writeShort(out, flags);
writeShort(out, method);
if (currentEntry.getTime() == -1) {
currentEntry.setTime(System.currentTimeMillis());
}
writeShort(out, currentEntry.time);
writeShort(out, currentEntry.modDate);
if (method == STORED) {
writeLong(out, currentEntry.crc);
writeLong(out, currentEntry.size);
writeLong(out, currentEntry.size);
} else {
writeLong(out, 0);
writeLong(out, 0);
writeLong(out, 0);
}
writeShort(out, nameBytes.length);
if (currentEntry.extra != null) {
writeShort(out, currentEntry.extra.length);
} else {
writeShort(out, 0);
}
out.write(nameBytes);
if (currentEntry.extra != null) {
out.write(currentEntry.extra);
}
}
/**
* Sets the comment associated with the file being written. See {@link ZipFile#getComment}.
* @throws IllegalArgumentException if the comment is >= 64 Ki encoded bytes.
*/
public void setComment(String comment) {
if (comment == null) {
this.commentBytes = EmptyArray.BYTE;
return;
}
byte[] newCommentBytes = comment.getBytes(StandardCharsets.UTF_8);
checkSizeIsWithinShort("Comment", newCommentBytes);
this.commentBytes = newCommentBytes;
}
/**
* Sets the <a href="Deflater.html#compression_level">compression level</a> to be used
* for writing entry data.
*/
public void setLevel(int level) {
if (level < Deflater.DEFAULT_COMPRESSION || level > Deflater.BEST_COMPRESSION) {
throw new IllegalArgumentException("Bad level: " + level);
}
compressionLevel = level;
}
/**
* Sets the default compression method to be used when a {@code ZipEntry} doesn't
* explicitly specify a method. See {@link ZipEntry#setMethod} for more details.
*/
public void setMethod(int method) {
if (method != STORED && method != DEFLATED) {
throw new IllegalArgumentException("Bad method: " + method);
}
defaultCompressionMethod = method;
}
private long writeLong(OutputStream os, long i) throws IOException {
// Write out the long value as an unsigned int
os.write((int) (i & 0xFF));
os.write((int) (i >> 8) & 0xFF);
os.write((int) (i >> 16) & 0xFF);
os.write((int) (i >> 24) & 0xFF);
return i;
}
private int writeShort(OutputStream os, int i) throws IOException {
os.write(i & 0xFF);
os.write((i >> 8) & 0xFF);
return i;
}
/**
* Writes data for the current entry to the underlying stream.
*
* @throws IOException
* If an error occurs writing to the stream
*/
@Override
public void write(byte[] buffer, int offset, int byteCount) throws IOException {
Arrays.checkOffsetAndCount(buffer.length, offset, byteCount);
if (currentEntry == null) {
throw new ZipException("No active entry");
}
if (currentEntry.getMethod() == STORED) {
out.write(buffer, offset, byteCount);
} else {
super.write(buffer, offset, byteCount);
}
crc.update(buffer, offset, byteCount);
}
private void checkOpen() throws IOException {
if (cDir == null) {
throw new IOException("Stream is closed");
}
}
private void checkSizeIsWithinShort(String property, byte[] bytes) {
if (bytes.length > 0xffff) {
throw new IllegalArgumentException(property + " too long in UTF-8:" + bytes.length +
" bytes");
}
}
}