org.apache.commons.compress.archivers.sevenz.SevenZFile Maven / Gradle / Ivy
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Apache Commons Compress defines an API for working with
compression and archive formats. These include bzip2, gzip, pack200,
LZMA, XZ, Snappy, traditional Unix Compress, DEFLATE, DEFLATE64, LZ4,
Brotli, Zstandard and ar, cpio, jar, tar, zip, dump, 7z, arj.
/*
* 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 org.apache.commons.compress.archivers.sevenz;
import static java.nio.charset.StandardCharsets.UTF_16LE;
import java.io.BufferedInputStream;
import java.io.ByteArrayInputStream;
import java.io.Closeable;
import java.io.DataInputStream;
import java.io.EOFException;
import java.io.File;
import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.channels.Channels;
import java.nio.channels.SeekableByteChannel;
import java.nio.file.Files;
import java.nio.file.OpenOption;
import java.nio.file.Path;
import java.nio.file.StandardOpenOption;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.BitSet;
import java.util.EnumSet;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.zip.CRC32;
import java.util.zip.CheckedInputStream;
import org.apache.commons.compress.MemoryLimitException;
import org.apache.commons.compress.utils.BoundedInputStream;
import org.apache.commons.compress.utils.ByteUtils;
import org.apache.commons.compress.utils.CRC32VerifyingInputStream;
import org.apache.commons.compress.utils.IOUtils;
import org.apache.commons.compress.utils.InputStreamStatistics;
import org.apache.commons.compress.utils.SeekableInMemoryByteChannel;
import org.apache.commons.io.build.AbstractOrigin.ByteArrayOrigin;
import org.apache.commons.io.build.AbstractStreamBuilder;
/**
* Reads a 7z file, using SeekableByteChannel under the covers.
*
* The 7z file format is a flexible container that can contain many compression and encryption types, but at the moment only only Copy, LZMA, LZMA2, BZIP2,
* Deflate and AES-256 + SHA-256 are supported.
*
*
* The format is very Windows/Intel specific, so it uses little-endian byte order, doesn't store user/group or permission bits, and represents times using NTFS
* timestamps (100 nanosecond units since 1 January 1601). Hence the official tools recommend against using it for backup purposes on *nix, and recommend
* .tar.7z or .tar.lzma or .tar.xz instead.
*
*
* Both the header and file contents may be compressed and/or encrypted. With both encrypted, neither file names nor file contents can be read, but the use of
* encryption isn't plausibly deniable.
*
*
* Multi volume archives can be read by concatenating the parts in correct order - either manually or by using {link
* org.apache.commons.compress.utils.MultiReadOnlySeekableByteChannel} for example.
*
*
* @NotThreadSafe
* @since 1.6
*/
public class SevenZFile implements Closeable {
private static final class ArchiveStatistics {
private int numberOfPackedStreams;
private long numberOfCoders;
private long numberOfOutStreams;
private long numberOfInStreams;
private long numberOfUnpackSubStreams;
private int numberOfFolders;
private BitSet folderHasCrc;
private int numberOfEntries;
private int numberOfEntriesWithStream;
void assertValidity(final int maxMemoryLimitInKb) throws IOException {
if (numberOfEntriesWithStream > 0 && numberOfFolders == 0) {
throw new IOException("archive with entries but no folders");
}
if (numberOfEntriesWithStream > numberOfUnpackSubStreams) {
throw new IOException("archive doesn't contain enough substreams for entries");
}
final long memoryNeededInKb = estimateSize() / 1024;
if (maxMemoryLimitInKb < memoryNeededInKb) {
throw new MemoryLimitException(memoryNeededInKb, maxMemoryLimitInKb);
}
}
private long bindPairSize() {
return 16;
}
private long coderSize() {
return 2 /* methodId is between 1 and four bytes currently, COPY and LZMA2 are the most common with 1 */
+ 16 + 4 /* properties, guess */
;
}
private long entrySize() {
return 100; /* real size depends on name length, everything without name is about 70 bytes */
}
long estimateSize() {
final long lowerBound = 16L * numberOfPackedStreams /* packSizes, packCrcs in Archive */
+ numberOfPackedStreams / 8 /* packCrcsDefined in Archive */
+ numberOfFolders * folderSize() /* folders in Archive */
+ numberOfCoders * coderSize() /* coders in Folder */
+ (numberOfOutStreams - numberOfFolders) * bindPairSize() /* bindPairs in Folder */
+ 8L * (numberOfInStreams - numberOfOutStreams + numberOfFolders) /* packedStreams in Folder */
+ 8L * numberOfOutStreams /* unpackSizes in Folder */
+ numberOfEntries * entrySize() /* files in Archive */
+ streamMapSize();
return 2 * lowerBound /* conservative guess */;
}
private long folderSize() {
return 30; /* nested arrays are accounted for separately */
}
private long streamMapSize() {
return 8 * numberOfFolders /* folderFirstPackStreamIndex, folderFirstFileIndex */
+ 8 * numberOfPackedStreams /* packStreamOffsets */
+ 4 * numberOfEntries /* fileFolderIndex */
;
}
@Override
public String toString() {
return "Archive with " + numberOfEntries + " entries in " + numberOfFolders + " folders. Estimated size " + estimateSize() / 1024L + " kB.";
}
}
/**
* Builds new instances of {@link SevenZFile}.
*
* @since 1.26.0
*/
public static class Builder extends AbstractStreamBuilder {
static final int MEMORY_LIMIT_IN_KB = Integer.MAX_VALUE;
static final boolean USE_DEFAULTNAME_FOR_UNNAMED_ENTRIES = false;
static final boolean TRY_TO_RECOVER_BROKEN_ARCHIVES = false;
private SeekableByteChannel seekableByteChannel;
private String defaultName = DEFAULT_FILE_NAME;
private byte[] password;
private int maxMemoryLimitKb = MEMORY_LIMIT_IN_KB;
private boolean useDefaultNameForUnnamedEntries = USE_DEFAULTNAME_FOR_UNNAMED_ENTRIES;
private boolean tryToRecoverBrokenArchives = TRY_TO_RECOVER_BROKEN_ARCHIVES;
@SuppressWarnings("resource") // Caller closes
@Override
public SevenZFile get() throws IOException {
final SeekableByteChannel actualChannel;
final String actualDescription;
if (seekableByteChannel != null) {
actualChannel = seekableByteChannel;
actualDescription = defaultName;
} else if (checkOrigin() instanceof ByteArrayOrigin) {
actualChannel = new SeekableInMemoryByteChannel(checkOrigin().getByteArray());
actualDescription = defaultName;
} else {
OpenOption[] openOptions = getOpenOptions();
if (openOptions.length == 0) {
openOptions = new OpenOption[] { StandardOpenOption.READ };
}
final Path path = getPath();
actualChannel = Files.newByteChannel(path, openOptions);
actualDescription = path.toAbsolutePath().toString();
}
final boolean closeOnError = seekableByteChannel != null;
return new SevenZFile(actualChannel, actualDescription, password, closeOnError, maxMemoryLimitKb, useDefaultNameForUnnamedEntries,
tryToRecoverBrokenArchives);
}
/**
* Sets the default name.
*
* @param defaultName the default name.
* @return this.
*/
public Builder setDefaultName(final String defaultName) {
this.defaultName = defaultName;
return this;
}
/**
* Sets the maximum amount of memory in kilobytes to use for parsing the archive and during extraction.
*
* Not all codecs honor this setting. Currently only LZMA and LZMA2 are supported.
*
*
* @param maxMemoryLimitKb the max memory limit in kilobytes.
* @return this.
*/
public Builder setMaxMemoryLimitKb(final int maxMemoryLimitKb) {
this.maxMemoryLimitKb = maxMemoryLimitKb;
return this;
}
/**
* Sets the password.
*
* @param password the password.
* @return this.
*/
public Builder setPassword(final byte[] password) {
this.password = password != null ? password.clone() : null;
return this;
}
/**
* Sets the password.
*
* @param password the password.
* @return this.
*/
public Builder setPassword(final char[] password) {
this.password = password != null ? AES256SHA256Decoder.utf16Decode(password.clone()) : null;
return this;
}
/**
* Sets the password.
*
* @param password the password.
* @return this.
*/
public Builder setPassword(final String password) {
this.password = password != null ? AES256SHA256Decoder.utf16Decode(password.toCharArray()) : null;
return this;
}
/**
* Sets the input channel.
*
* @param seekableByteChannel the input channel.
* @return this.
*/
public Builder setSeekableByteChannel(final SeekableByteChannel seekableByteChannel) {
this.seekableByteChannel = seekableByteChannel;
return this;
}
/**
* Sets whether {@link SevenZFile} will try to recover broken archives where the CRC of the file's metadata is 0.
*
* This special kind of broken archive is encountered when mutli volume archives are closed prematurely. If you enable this option SevenZFile will trust
* data that looks as if it could contain metadata of an archive and allocate big amounts of memory. It is strongly recommended to not enable this
* option without setting {@link #setMaxMemoryLimitKb(int)} at the same time.
*
*
* @param tryToRecoverBrokenArchives whether {@link SevenZFile} will try to recover broken archives where the CRC of the file's metadata is 0.
* @return this.
*/
public Builder setTryToRecoverBrokenArchives(final boolean tryToRecoverBrokenArchives) {
this.tryToRecoverBrokenArchives = tryToRecoverBrokenArchives;
return this;
}
/**
* Sets whether entries without a name should get their names set to the archive's default file name.
*
* @param useDefaultNameForUnnamedEntries whether entries without a name should get their names set to the archive's default file name.
* @return this.
*/
public Builder setUseDefaultNameForUnnamedEntries(final boolean useDefaultNameForUnnamedEntries) {
this.useDefaultNameForUnnamedEntries = useDefaultNameForUnnamedEntries;
return this;
}
}
static final int SIGNATURE_HEADER_SIZE = 32;
private static final String DEFAULT_FILE_NAME = "unknown archive";
/** Shared with SevenZOutputFile and tests, neither mutates it. */
static final byte[] sevenZSignature = { // NOSONAR
(byte) '7', (byte) 'z', (byte) 0xBC, (byte) 0xAF, (byte) 0x27, (byte) 0x1C };
private static int assertFitsIntoNonNegativeInt(final String what, final long value) throws IOException {
if (value > Integer.MAX_VALUE || value < 0) {
throw new IOException(String.format("Cannot handle % %,d", what, value));
}
return (int) value;
}
/**
* Creates a new Builder.
*
* @return a new Builder.
* @since 1.26.0
*/
public static Builder builder() {
return new Builder();
}
private static ByteBuffer checkEndOfFile(final ByteBuffer buf, final int expectRemaining) throws EOFException {
final int remaining = buf.remaining();
if (remaining < expectRemaining) {
throw new EOFException(String.format("remaining %,d < expectRemaining %,d", remaining, expectRemaining));
}
return buf;
}
private static void get(final ByteBuffer buf, final byte[] to) throws EOFException {
checkEndOfFile(buf, to.length).get(to);
}
private static char getChar(final ByteBuffer buf) throws EOFException {
return checkEndOfFile(buf, Character.BYTES).getChar();
}
private static int getInt(final ByteBuffer buf) throws EOFException {
return checkEndOfFile(buf, Integer.BYTES).getInt();
}
private static long getLong(final ByteBuffer buf) throws EOFException {
return checkEndOfFile(buf, Long.BYTES).getLong();
}
private static int getUnsignedByte(final ByteBuffer buf) throws EOFException {
if (!buf.hasRemaining()) {
throw new EOFException();
}
return buf.get() & 0xff;
}
/**
* Checks if the signature matches what is expected for a 7z file.
*
* @param signature the bytes to check
* @param length the number of bytes to check
* @return true, if this is the signature of a 7z archive.
* @since 1.8
*/
public static boolean matches(final byte[] signature, final int length) {
if (length < sevenZSignature.length) {
return false;
}
for (int i = 0; i < sevenZSignature.length; i++) {
if (signature[i] != sevenZSignature[i]) {
return false;
}
}
return true;
}
private static SeekableByteChannel newByteChannel(final File file) throws IOException {
return Files.newByteChannel(file.toPath(), EnumSet.of(StandardOpenOption.READ));
}
private static long readUint64(final ByteBuffer in) throws IOException {
// long rather than int as it might get shifted beyond the range of an int
final long firstByte = getUnsignedByte(in);
int mask = 0x80;
long value = 0;
for (int i = 0; i < 8; i++) {
if ((firstByte & mask) == 0) {
return value | (firstByte & mask - 1) << 8 * i;
}
final long nextByte = getUnsignedByte(in);
value |= nextByte << 8 * i;
mask >>>= 1;
}
return value;
}
private static long skipBytesFully(final ByteBuffer input, long bytesToSkip) {
if (bytesToSkip < 1) {
return 0;
}
final int current = input.position();
final int maxSkip = input.remaining();
if (maxSkip < bytesToSkip) {
bytesToSkip = maxSkip;
}
input.position(current + (int) bytesToSkip);
return bytesToSkip;
}
private final String fileName;
private SeekableByteChannel channel;
private final Archive archive;
private int currentEntryIndex = -1;
private int currentFolderIndex = -1;
private InputStream currentFolderInputStream;
private byte[] password;
private long compressedBytesReadFromCurrentEntry;
private long uncompressedBytesReadFromCurrentEntry;
private final ArrayList deferredBlockStreams = new ArrayList<>();
private final int maxMemoryLimitKb;
private final boolean useDefaultNameForUnnamedEntries;
private final boolean tryToRecoverBrokenArchives;
/**
* Reads a file as unencrypted 7z archive.
*
* @param fileName the file to read.
* @throws IOException if reading the archive fails.
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
public SevenZFile(final File fileName) throws IOException {
this(fileName, SevenZFileOptions.DEFAULT);
}
/**
* Reads a file as 7z archive
*
* @param file the file to read
* @param password optional password if the archive is encrypted - the byte array is supposed to be the UTF16-LE encoded representation of the password.
* @throws IOException if reading the archive fails
* @deprecated Use {@link Builder#get()}.
*/
@SuppressWarnings("resource") // caller closes
@Deprecated
public SevenZFile(final File file, final byte[] password) throws IOException {
this(newByteChannel(file), file.getAbsolutePath(), password, true, SevenZFileOptions.DEFAULT);
}
/**
* Reads a file as 7z archive
*
* @param file the file to read
* @param password optional password if the archive is encrypted
* @throws IOException if reading the archive fails
* @since 1.17
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
public SevenZFile(final File file, final char[] password) throws IOException {
this(file, password, SevenZFileOptions.DEFAULT);
}
/**
* Reads a file as 7z archive with additional options.
*
* @param file the file to read
* @param password optional password if the archive is encrypted
* @param options the options to apply
* @throws IOException if reading the archive fails or the memory limit (if set) is too small
* @since 1.19
* @deprecated Use {@link Builder#get()}.
*/
@SuppressWarnings("resource") // caller closes
@Deprecated
public SevenZFile(final File file, final char[] password, final SevenZFileOptions options) throws IOException {
this(newByteChannel(file), // NOSONAR
file.getAbsolutePath(), AES256SHA256Decoder.utf16Decode(password), true, options);
}
/**
* Reads a file as unencrypted 7z archive
*
* @param file the file to read
* @param options the options to apply
* @throws IOException if reading the archive fails or the memory limit (if set) is too small
* @since 1.19
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
public SevenZFile(final File file, final SevenZFileOptions options) throws IOException {
this(file, null, options);
}
/**
* Reads a SeekableByteChannel as 7z archive
*
* {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
*
*
* @param channel the channel to read
* @throws IOException if reading the archive fails
* @since 1.13
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
public SevenZFile(final SeekableByteChannel channel) throws IOException {
this(channel, SevenZFileOptions.DEFAULT);
}
/**
* Reads a SeekableByteChannel as 7z archive
*
* {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
*
*
* @param channel the channel to read
* @param password optional password if the archive is encrypted - the byte array is supposed to be the UTF16-LE encoded representation of the password.
* @throws IOException if reading the archive fails
* @since 1.13
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
public SevenZFile(final SeekableByteChannel channel, final byte[] password) throws IOException {
this(channel, DEFAULT_FILE_NAME, password);
}
/**
* Reads a SeekableByteChannel as 7z archive
*
* {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
*
*
* @param channel the channel to read
* @param password optional password if the archive is encrypted
* @throws IOException if reading the archive fails
* @since 1.17
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
public SevenZFile(final SeekableByteChannel channel, final char[] password) throws IOException {
this(channel, password, SevenZFileOptions.DEFAULT);
}
/**
* Reads a SeekableByteChannel as 7z archive with additional options.
*
* {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
*
*
* @param channel the channel to read
* @param password optional password if the archive is encrypted
* @param options the options to apply
* @throws IOException if reading the archive fails or the memory limit (if set) is too small
* @since 1.19
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
public SevenZFile(final SeekableByteChannel channel, final char[] password, final SevenZFileOptions options) throws IOException {
this(channel, DEFAULT_FILE_NAME, password, options);
}
/**
* Reads a SeekableByteChannel as 7z archive with additional options.
*
* {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
*
*
* @param channel the channel to read
* @param options the options to apply
* @throws IOException if reading the archive fails or the memory limit (if set) is too small
* @since 1.19
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
public SevenZFile(final SeekableByteChannel channel, final SevenZFileOptions options) throws IOException {
this(channel, DEFAULT_FILE_NAME, null, options);
}
/**
* Reads a SeekableByteChannel as 7z archive
*
* {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
*
*
* @param channel the channel to read
* @param fileName name of the archive - only used for error reporting
* @throws IOException if reading the archive fails
* @since 1.17
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
public SevenZFile(final SeekableByteChannel channel, final String fileName) throws IOException {
this(channel, fileName, SevenZFileOptions.DEFAULT);
}
/**
* Reads a SeekableByteChannel as 7z archive
*
* {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
*
*
* @param channel the channel to read
* @param fileName name of the archive - only used for error reporting
* @param password optional password if the archive is encrypted - the byte array is supposed to be the UTF16-LE encoded representation of the password.
* @throws IOException if reading the archive fails
* @since 1.13
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
public SevenZFile(final SeekableByteChannel channel, final String fileName, final byte[] password) throws IOException {
this(channel, fileName, password, false, SevenZFileOptions.DEFAULT);
}
private SevenZFile(final SeekableByteChannel channel, final String fileName, final byte[] password, final boolean closeOnError, final int maxMemoryLimitKb,
final boolean useDefaultNameForUnnamedEntries, final boolean tryToRecoverBrokenArchives) throws IOException {
boolean succeeded = false;
this.channel = channel;
this.fileName = fileName;
this.maxMemoryLimitKb = maxMemoryLimitKb;
this.useDefaultNameForUnnamedEntries = useDefaultNameForUnnamedEntries;
this.tryToRecoverBrokenArchives = tryToRecoverBrokenArchives;
try {
archive = readHeaders(password);
if (password != null) {
this.password = Arrays.copyOf(password, password.length);
} else {
this.password = null;
}
succeeded = true;
} finally {
if (!succeeded && closeOnError) {
this.channel.close();
}
}
}
/**
* Constructs a new instance.
*
* @param channel the channel to read.
* @param fileName name of the archive - only used for error reporting.
* @param password optional password if the archive is encrypted.
* @param closeOnError closes the channel on error.
* @param options options.
* @throws IOException if reading the archive fails
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
private SevenZFile(final SeekableByteChannel channel, final String fileName, final byte[] password, final boolean closeOnError,
final SevenZFileOptions options) throws IOException {
this(channel, fileName, password, closeOnError, options.getMaxMemoryLimitInKb(), options.getUseDefaultNameForUnnamedEntries(),
options.getTryToRecoverBrokenArchives());
}
/**
* Reads a SeekableByteChannel as 7z archive
*
* {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
*
*
* @param channel the channel to read
* @param fileName name of the archive - only used for error reporting
* @param password optional password if the archive is encrypted
* @throws IOException if reading the archive fails
* @since 1.17
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
public SevenZFile(final SeekableByteChannel channel, final String fileName, final char[] password) throws IOException {
this(channel, fileName, password, SevenZFileOptions.DEFAULT);
}
/**
* Reads a SeekableByteChannel as 7z archive with additional options.
*
* {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
*
*
* @param channel the channel to read
* @param fileName name of the archive - only used for error reporting
* @param password optional password if the archive is encrypted
* @param options the options to apply
* @throws IOException if reading the archive fails or the memory limit (if set) is too small
* @since 1.19
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
public SevenZFile(final SeekableByteChannel channel, final String fileName, final char[] password, final SevenZFileOptions options) throws IOException {
this(channel, fileName, AES256SHA256Decoder.utf16Decode(password), false, options);
}
/**
* Reads a SeekableByteChannel as 7z archive with additional options.
*
* {@link org.apache.commons.compress.utils.SeekableInMemoryByteChannel} allows you to read from an in-memory archive.
*
*
* @param channel the channel to read
* @param fileName name of the archive - only used for error reporting
* @param options the options to apply
* @throws IOException if reading the archive fails or the memory limit (if set) is too small
* @since 1.19
* @deprecated Use {@link Builder#get()}.
*/
@Deprecated
public SevenZFile(final SeekableByteChannel channel, final String fileName, final SevenZFileOptions options) throws IOException {
this(channel, fileName, null, false, options);
}
private InputStream buildDecoderStack(final Folder folder, final long folderOffset, final int firstPackStreamIndex, final SevenZArchiveEntry entry)
throws IOException {
channel.position(folderOffset);
InputStream inputStreamStack = new FilterInputStream(
new BufferedInputStream(new BoundedSeekableByteChannelInputStream(channel, archive.packSizes[firstPackStreamIndex]))) {
private void count(final int c) {
compressedBytesReadFromCurrentEntry += c;
}
@Override
public int read() throws IOException {
final int r = in.read();
if (r >= 0) {
count(1);
}
return r;
}
@Override
public int read(final byte[] b) throws IOException {
return read(b, 0, b.length);
}
@Override
public int read(final byte[] b, final int off, final int len) throws IOException {
if (len == 0) {
return 0;
}
final int r = in.read(b, off, len);
if (r >= 0) {
count(r);
}
return r;
}
};
final LinkedList methods = new LinkedList<>();
for (final Coder coder : folder.getOrderedCoders()) {
if (coder.numInStreams != 1 || coder.numOutStreams != 1) {
throw new IOException("Multi input/output stream coders are not yet supported");
}
final SevenZMethod method = SevenZMethod.byId(coder.decompressionMethodId);
inputStreamStack = Coders.addDecoder(fileName, inputStreamStack, folder.getUnpackSizeForCoder(coder), coder, password, maxMemoryLimitKb);
methods.addFirst(new SevenZMethodConfiguration(method, Coders.findByMethod(method).getOptionsFromCoder(coder, inputStreamStack)));
}
entry.setContentMethods(methods);
if (folder.hasCrc) {
return new CRC32VerifyingInputStream(inputStreamStack, folder.getUnpackSize(), folder.crc);
}
return inputStreamStack;
}
/**
* Builds the decoding stream for the entry to be read. This method may be called from a random access(getInputStream) or sequential access(getNextEntry).
* If this method is called from a random access, some entries may need to be skipped(we put them to the deferredBlockStreams and skip them when actually
* needed to improve the performance)
*
* @param entryIndex the index of the entry to be read
* @param isRandomAccess is this called in a random access
* @throws IOException if there are exceptions when reading the file
*/
private void buildDecodingStream(final int entryIndex, final boolean isRandomAccess) throws IOException {
if (archive.streamMap == null) {
throw new IOException("Archive doesn't contain stream information to read entries");
}
final int folderIndex = archive.streamMap.fileFolderIndex[entryIndex];
if (folderIndex < 0) {
deferredBlockStreams.clear();
// TODO: previously it'd return an empty stream?
// new BoundedInputStream(new ByteArrayInputStream(ByteUtils.EMPTY_BYTE_ARRAY), 0);
return;
}
final SevenZArchiveEntry file = archive.files[entryIndex];
boolean isInSameFolder = false;
if (currentFolderIndex == folderIndex) {
// (COMPRESS-320).
// The current entry is within the same (potentially opened) folder. The
// previous stream has to be fully decoded before we can start reading
// but don't do it eagerly -- if the user skips over the entire folder nothing
// is effectively decompressed.
if (entryIndex > 0) {
file.setContentMethods(archive.files[entryIndex - 1].getContentMethods());
}
// if this is called in a random access, then the content methods of previous entry may be null
// the content methods should be set to methods of the first entry as it must not be null,
// and the content methods would only be set if the content methods was not set
if (isRandomAccess && file.getContentMethods() == null) {
final int folderFirstFileIndex = archive.streamMap.folderFirstFileIndex[folderIndex];
final SevenZArchiveEntry folderFirstFile = archive.files[folderFirstFileIndex];
file.setContentMethods(folderFirstFile.getContentMethods());
}
isInSameFolder = true;
} else {
currentFolderIndex = folderIndex;
// We're opening a new folder. Discard any queued streams/ folder stream.
reopenFolderInputStream(folderIndex, file);
}
boolean haveSkippedEntries = false;
if (isRandomAccess) {
// entries will only need to be skipped if it's a random access
haveSkippedEntries = skipEntriesWhenNeeded(entryIndex, isInSameFolder, folderIndex);
}
if (isRandomAccess && currentEntryIndex == entryIndex && !haveSkippedEntries) {
// we don't need to add another entry to the deferredBlockStreams when :
// 1. If this method is called in a random access and the entry index
// to be read equals to the current entry index, the input stream
// has already been put in the deferredBlockStreams
// 2. If this entry has not been read(which means no entries are skipped)
return;
}
InputStream fileStream = new BoundedInputStream(currentFolderInputStream, file.getSize());
if (file.getHasCrc()) {
fileStream = new CRC32VerifyingInputStream(fileStream, file.getSize(), file.getCrcValue());
}
deferredBlockStreams.add(fileStream);
}
private void calculateStreamMap(final Archive archive) throws IOException {
int nextFolderPackStreamIndex = 0;
final int numFolders = archive.folders != null ? archive.folders.length : 0;
final int[] folderFirstPackStreamIndex = new int[numFolders];
for (int i = 0; i < numFolders; i++) {
folderFirstPackStreamIndex[i] = nextFolderPackStreamIndex;
nextFolderPackStreamIndex += archive.folders[i].packedStreams.length;
}
long nextPackStreamOffset = 0;
final int numPackSizes = archive.packSizes.length;
final long[] packStreamOffsets = new long[numPackSizes];
for (int i = 0; i < numPackSizes; i++) {
packStreamOffsets[i] = nextPackStreamOffset;
nextPackStreamOffset += archive.packSizes[i];
}
final int[] folderFirstFileIndex = new int[numFolders];
final int[] fileFolderIndex = new int[archive.files.length];
int nextFolderIndex = 0;
int nextFolderUnpackStreamIndex = 0;
for (int i = 0; i < archive.files.length; i++) {
if (!archive.files[i].hasStream() && nextFolderUnpackStreamIndex == 0) {
fileFolderIndex[i] = -1;
continue;
}
if (nextFolderUnpackStreamIndex == 0) {
for (; nextFolderIndex < archive.folders.length; ++nextFolderIndex) {
folderFirstFileIndex[nextFolderIndex] = i;
if (archive.folders[nextFolderIndex].numUnpackSubStreams > 0) {
break;
}
}
if (nextFolderIndex >= archive.folders.length) {
throw new IOException("Too few folders in archive");
}
}
fileFolderIndex[i] = nextFolderIndex;
if (!archive.files[i].hasStream()) {
continue;
}
++nextFolderUnpackStreamIndex;
if (nextFolderUnpackStreamIndex >= archive.folders[nextFolderIndex].numUnpackSubStreams) {
++nextFolderIndex;
nextFolderUnpackStreamIndex = 0;
}
}
archive.streamMap = new StreamMap(folderFirstPackStreamIndex, packStreamOffsets, folderFirstFileIndex, fileFolderIndex);
}
private void checkEntryIsInitialized(final Map archiveEntries, final int index) {
archiveEntries.computeIfAbsent(index, i -> new SevenZArchiveEntry());
}
/**
* Closes the archive.
*
* @throws IOException if closing the file fails
*/
@Override
public void close() throws IOException {
if (channel != null) {
try {
channel.close();
} finally {
channel = null;
if (password != null) {
Arrays.fill(password, (byte) 0);
}
password = null;
}
}
}
private InputStream getCurrentStream() throws IOException {
if (archive.files[currentEntryIndex].getSize() == 0) {
return new ByteArrayInputStream(ByteUtils.EMPTY_BYTE_ARRAY);
}
if (deferredBlockStreams.isEmpty()) {
throw new IllegalStateException("No current 7z entry (call getNextEntry() first).");
}
while (deferredBlockStreams.size() > 1) {
// In solid compression mode we need to decompress all leading folder'
// streams to get access to an entry. We defer this until really needed
// so that entire blocks can be skipped without wasting time for decompression.
try (InputStream stream = deferredBlockStreams.remove(0)) {
org.apache.commons.io.IOUtils.skip(stream, Long.MAX_VALUE);
}
compressedBytesReadFromCurrentEntry = 0;
}
return deferredBlockStreams.get(0);
}
/**
* Gets a default file name from the archive name - if known.
*
* This implements the same heuristics the 7z tools use. In 7z's case if an archive contains entries without a name - i.e.
* {@link SevenZArchiveEntry#getName} returns {@code null} - then its command line and GUI tools will use this default name when extracting the entries.
*
*
* @return null if the name of the archive is unknown. Otherwise, if the name of the archive has got any extension, it is stripped and the remainder
* returned. Finally, if the name of the archive hasn't got any extension, then a {@code ~} character is appended to the archive name.
* @since 1.19
*/
public String getDefaultName() {
if (DEFAULT_FILE_NAME.equals(fileName) || fileName == null) {
return null;
}
final String lastSegment = new File(fileName).getName();
final int dotPos = lastSegment.lastIndexOf(".");
if (dotPos > 0) { // if the file starts with a dot then this is not an extension
return lastSegment.substring(0, dotPos);
}
return lastSegment + "~";
}
/**
* Gets a copy of meta-data of all archive entries.
*
* This method only provides meta-data, the entries can not be used to read the contents, you still need to process all entries in order using
* {@link #getNextEntry} for that.
*
*
* The content methods are only available for entries that have already been reached via {@link #getNextEntry}.
*
*
* @return a copy of meta-data of all archive entries.
* @since 1.11
*/
public Iterable getEntries() {
return new ArrayList<>(Arrays.asList(archive.files));
}
/**
* Gets an InputStream for reading the contents of the given entry.
*
* For archives using solid compression randomly accessing entries will be significantly slower than reading the archive sequentially.
*
*
* @param entry the entry to get the stream for.
* @return a stream to read the entry from.
* @throws IOException if unable to create an input stream from the entry
* @since 1.20
*/
public InputStream getInputStream(final SevenZArchiveEntry entry) throws IOException {
int entryIndex = -1;
for (int i = 0; i < this.archive.files.length; i++) {
if (entry == this.archive.files[i]) {
entryIndex = i;
break;
}
}
if (entryIndex < 0) {
throw new IllegalArgumentException("Can not find " + entry.getName() + " in " + this.fileName);
}
buildDecodingStream(entryIndex, true);
currentEntryIndex = entryIndex;
currentFolderIndex = archive.streamMap.fileFolderIndex[entryIndex];
return getCurrentStream();
}
/**
* Gets the next Archive Entry in this archive.
*
* @return the next entry, or {@code null} if there are no more entries
* @throws IOException if the next entry could not be read
*/
public SevenZArchiveEntry getNextEntry() throws IOException {
if (currentEntryIndex >= archive.files.length - 1) {
return null;
}
++currentEntryIndex;
final SevenZArchiveEntry entry = archive.files[currentEntryIndex];
if (entry.getName() == null && useDefaultNameForUnnamedEntries) {
entry.setName(getDefaultName());
}
buildDecodingStream(currentEntryIndex, false);
uncompressedBytesReadFromCurrentEntry = compressedBytesReadFromCurrentEntry = 0;
return entry;
}
/**
* Gets statistics for bytes read from the current entry.
*
* @return statistics for bytes read from the current entry
* @since 1.17
*/
public InputStreamStatistics getStatisticsForCurrentEntry() {
return new InputStreamStatistics() {
@Override
public long getCompressedCount() {
return compressedBytesReadFromCurrentEntry;
}
@Override
public long getUncompressedCount() {
return uncompressedBytesReadFromCurrentEntry;
}
};
}
/**
* Tests if any data of current entry has been read or not. This is achieved by comparing the bytes remaining to read and the size of the file.
*
* @return true if any data of current entry has been read
* @since 1.21
*/
private boolean hasCurrentEntryBeenRead() {
boolean hasCurrentEntryBeenRead = false;
if (!deferredBlockStreams.isEmpty()) {
final InputStream currentEntryInputStream = deferredBlockStreams.get(deferredBlockStreams.size() - 1);
// get the bytes remaining to read, and compare it with the size of
// the file to figure out if the file has been read
if (currentEntryInputStream instanceof CRC32VerifyingInputStream) {
hasCurrentEntryBeenRead = ((CRC32VerifyingInputStream) currentEntryInputStream).getBytesRemaining() != archive.files[currentEntryIndex]
.getSize();
}
if (currentEntryInputStream instanceof BoundedInputStream) {
hasCurrentEntryBeenRead = ((BoundedInputStream) currentEntryInputStream).getBytesRemaining() != archive.files[currentEntryIndex].getSize();
}
}
return hasCurrentEntryBeenRead;
}
private Archive initializeArchive(final StartHeader startHeader, final byte[] password, final boolean verifyCrc) throws IOException {
assertFitsIntoNonNegativeInt("nextHeaderSize", startHeader.nextHeaderSize);
final int nextHeaderSizeInt = (int) startHeader.nextHeaderSize;
channel.position(SIGNATURE_HEADER_SIZE + startHeader.nextHeaderOffset);
if (verifyCrc) {
final long position = channel.position();
final CheckedInputStream cis = new CheckedInputStream(Channels.newInputStream(channel), new CRC32());
if (cis.skip(nextHeaderSizeInt) != nextHeaderSizeInt) {
throw new IOException("Problem computing NextHeader CRC-32");
}
if (startHeader.nextHeaderCrc != cis.getChecksum().getValue()) {
throw new IOException("NextHeader CRC-32 mismatch");
}
channel.position(position);
}
Archive archive = new Archive();
ByteBuffer buf = ByteBuffer.allocate(nextHeaderSizeInt).order(ByteOrder.LITTLE_ENDIAN);
readFully(buf);
int nid = getUnsignedByte(buf);
if (nid == NID.kEncodedHeader) {
buf = readEncodedHeader(buf, archive, password);
// Archive gets rebuilt with the new header
archive = new Archive();
nid = getUnsignedByte(buf);
}
if (nid != NID.kHeader) {
throw new IOException("Broken or unsupported archive: no Header");
}
readHeader(buf, archive);
archive.subStreamsInfo = null;
return archive;
}
/**
* Reads a byte of data.
*
* @return the byte read, or -1 if end of input is reached
* @throws IOException if an I/O error has occurred
*/
public int read() throws IOException {
final int b = getCurrentStream().read();
if (b >= 0) {
uncompressedBytesReadFromCurrentEntry++;
}
return b;
}
/**
* Reads data into an array of bytes.
*
* @param b the array to write data to
* @return the number of bytes read, or -1 if end of input is reached
* @throws IOException if an I/O error has occurred
*/
public int read(final byte[] b) throws IOException {
return read(b, 0, b.length);
}
/**
* Reads data into an array of bytes.
*
* @param b the array to write data to
* @param off offset into the buffer to start filling at
* @param len of bytes to read
* @return the number of bytes read, or -1 if end of input is reached
* @throws IOException if an I/O error has occurred
*/
public int read(final byte[] b, final int off, final int len) throws IOException {
if (len == 0) {
return 0;
}
final int cnt = getCurrentStream().read(b, off, len);
if (cnt > 0) {
uncompressedBytesReadFromCurrentEntry += cnt;
}
return cnt;
}
private BitSet readAllOrBits(final ByteBuffer header, final int size) throws IOException {
final int areAllDefined = getUnsignedByte(header);
final BitSet bits;
if (areAllDefined != 0) {
bits = new BitSet(size);
for (int i = 0; i < size; i++) {
bits.set(i, true);
}
} else {
bits = readBits(header, size);
}
return bits;
}
private void readArchiveProperties(final ByteBuffer input) throws IOException {
// FIXME: the reference implementation just throws them away?
int nid = getUnsignedByte(input);
while (nid != NID.kEnd) {
final long propertySize = readUint64(input);
final byte[] property = new byte[(int) propertySize];
get(input, property);
nid = getUnsignedByte(input);
}
}
private BitSet readBits(final ByteBuffer header, final int size) throws IOException {
final BitSet bits = new BitSet(size);
int mask = 0;
int cache = 0;
for (int i = 0; i < size; i++) {
if (mask == 0) {
mask = 0x80;
cache = getUnsignedByte(header);
}
bits.set(i, (cache & mask) != 0);
mask >>>= 1;
}
return bits;
}
private ByteBuffer readEncodedHeader(final ByteBuffer header, final Archive archive, final byte[] password) throws IOException {
final int pos = header.position();
final ArchiveStatistics stats = new ArchiveStatistics();
sanityCheckStreamsInfo(header, stats);
stats.assertValidity(maxMemoryLimitKb);
header.position(pos);
readStreamsInfo(header, archive);
if (archive.folders == null || archive.folders.length == 0) {
throw new IOException("no folders, can't read encoded header");
}
if (archive.packSizes == null || archive.packSizes.length == 0) {
throw new IOException("no packed streams, can't read encoded header");
}
// FIXME: merge with buildDecodingStream()/buildDecoderStack() at some stage?
final Folder folder = archive.folders[0];
final int firstPackStreamIndex = 0;
final long folderOffset = SIGNATURE_HEADER_SIZE + archive.packPos + 0;
channel.position(folderOffset);
InputStream inputStreamStack = new BoundedSeekableByteChannelInputStream(channel, archive.packSizes[firstPackStreamIndex]);
for (final Coder coder : folder.getOrderedCoders()) {
if (coder.numInStreams != 1 || coder.numOutStreams != 1) {
throw new IOException("Multi input/output stream coders are not yet supported");
}
inputStreamStack = Coders.addDecoder(fileName, inputStreamStack, // NOSONAR
folder.getUnpackSizeForCoder(coder), coder, password, maxMemoryLimitKb);
}
if (folder.hasCrc) {
inputStreamStack = new CRC32VerifyingInputStream(inputStreamStack, folder.getUnpackSize(), folder.crc);
}
final int unpackSize = assertFitsIntoNonNegativeInt("unpackSize", folder.getUnpackSize());
final byte[] nextHeader = IOUtils.readRange(inputStreamStack, unpackSize);
if (nextHeader.length < unpackSize) {
throw new IOException("premature end of stream");
}
inputStreamStack.close();
return ByteBuffer.wrap(nextHeader).order(ByteOrder.LITTLE_ENDIAN);
}
private void readFilesInfo(final ByteBuffer header, final Archive archive) throws IOException {
final int numFilesInt = (int) readUint64(header);
final Map fileMap = new LinkedHashMap<>();
BitSet isEmptyStream = null;
BitSet isEmptyFile = null;
BitSet isAnti = null;
while (true) {
final int propertyType = getUnsignedByte(header);
if (propertyType == 0) {
break;
}
final long size = readUint64(header);
switch (propertyType) {
case NID.kEmptyStream: {
isEmptyStream = readBits(header, numFilesInt);
break;
}
case NID.kEmptyFile: {
isEmptyFile = readBits(header, isEmptyStream.cardinality());
break;
}
case NID.kAnti: {
isAnti = readBits(header, isEmptyStream.cardinality());
break;
}
case NID.kName: {
/* final int external = */ getUnsignedByte(header);
final byte[] names = new byte[(int) (size - 1)];
final int namesLength = names.length;
get(header, names);
int nextFile = 0;
int nextName = 0;
for (int i = 0; i < namesLength; i += 2) {
if (names[i] == 0 && names[i + 1] == 0) {
checkEntryIsInitialized(fileMap, nextFile);
fileMap.get(nextFile).setName(new String(names, nextName, i - nextName, UTF_16LE));
nextName = i + 2;
nextFile++;
}
}
if (nextName != namesLength || nextFile != numFilesInt) {
throw new IOException("Error parsing file names");
}
break;
}
case NID.kCTime: {
final BitSet timesDefined = readAllOrBits(header, numFilesInt);
/* final int external = */ getUnsignedByte(header);
for (int i = 0; i < numFilesInt; i++) {
checkEntryIsInitialized(fileMap, i);
final SevenZArchiveEntry entryAtIndex = fileMap.get(i);
entryAtIndex.setHasCreationDate(timesDefined.get(i));
if (entryAtIndex.getHasCreationDate()) {
entryAtIndex.setCreationDate(getLong(header));
}
}
break;
}
case NID.kATime: {
final BitSet timesDefined = readAllOrBits(header, numFilesInt);
/* final int external = */ getUnsignedByte(header);
for (int i = 0; i < numFilesInt; i++) {
checkEntryIsInitialized(fileMap, i);
final SevenZArchiveEntry entryAtIndex = fileMap.get(i);
entryAtIndex.setHasAccessDate(timesDefined.get(i));
if (entryAtIndex.getHasAccessDate()) {
entryAtIndex.setAccessDate(getLong(header));
}
}
break;
}
case NID.kMTime: {
final BitSet timesDefined = readAllOrBits(header, numFilesInt);
/* final int external = */ getUnsignedByte(header);
for (int i = 0; i < numFilesInt; i++) {
checkEntryIsInitialized(fileMap, i);
final SevenZArchiveEntry entryAtIndex = fileMap.get(i);
entryAtIndex.setHasLastModifiedDate(timesDefined.get(i));
if (entryAtIndex.getHasLastModifiedDate()) {
entryAtIndex.setLastModifiedDate(getLong(header));
}
}
break;
}
case NID.kWinAttributes: {
final BitSet attributesDefined = readAllOrBits(header, numFilesInt);
/* final int external = */ getUnsignedByte(header);
for (int i = 0; i < numFilesInt; i++) {
checkEntryIsInitialized(fileMap, i);
final SevenZArchiveEntry entryAtIndex = fileMap.get(i);
entryAtIndex.setHasWindowsAttributes(attributesDefined.get(i));
if (entryAtIndex.getHasWindowsAttributes()) {
entryAtIndex.setWindowsAttributes(getInt(header));
}
}
break;
}
case NID.kDummy: {
// 7z 9.20 asserts the content is all zeros and ignores the property
// Compress up to 1.8.1 would throw an exception, now we ignore it (see COMPRESS-287
skipBytesFully(header, size);
break;
}
default: {
// Compress up to 1.8.1 would throw an exception, now we ignore it (see COMPRESS-287
skipBytesFully(header, size);
break;
}
}
}
int nonEmptyFileCounter = 0;
int emptyFileCounter = 0;
for (int i = 0; i < numFilesInt; i++) {
final SevenZArchiveEntry entryAtIndex = fileMap.get(i);
if (entryAtIndex == null) {
continue;
}
entryAtIndex.setHasStream(isEmptyStream == null || !isEmptyStream.get(i));
if (entryAtIndex.hasStream()) {
if (archive.subStreamsInfo == null) {
throw new IOException("Archive contains file with streams but no subStreamsInfo");
}
entryAtIndex.setDirectory(false);
entryAtIndex.setAntiItem(false);
entryAtIndex.setHasCrc(archive.subStreamsInfo.hasCrc.get(nonEmptyFileCounter));
entryAtIndex.setCrcValue(archive.subStreamsInfo.crcs[nonEmptyFileCounter]);
entryAtIndex.setSize(archive.subStreamsInfo.unpackSizes[nonEmptyFileCounter]);
if (entryAtIndex.getSize() < 0) {
throw new IOException("broken archive, entry with negative size");
}
++nonEmptyFileCounter;
} else {
entryAtIndex.setDirectory(isEmptyFile == null || !isEmptyFile.get(emptyFileCounter));
entryAtIndex.setAntiItem(isAnti != null && isAnti.get(emptyFileCounter));
entryAtIndex.setHasCrc(false);
entryAtIndex.setSize(0);
++emptyFileCounter;
}
}
archive.files = fileMap.values().stream().filter(Objects::nonNull).toArray(SevenZArchiveEntry[]::new);
calculateStreamMap(archive);
}
private Folder readFolder(final ByteBuffer header) throws IOException {
final Folder folder = new Folder();
final long numCoders = readUint64(header);
final Coder[] coders = new Coder[(int) numCoders];
long totalInStreams = 0;
long totalOutStreams = 0;
for (int i = 0; i < coders.length; i++) {
final int bits = getUnsignedByte(header);
final int idSize = bits & 0xf;
final boolean isSimple = (bits & 0x10) == 0;
final boolean hasAttributes = (bits & 0x20) != 0;
final boolean moreAlternativeMethods = (bits & 0x80) != 0;
final byte[] decompressionMethodId = new byte[idSize];
get(header, decompressionMethodId);
final long numInStreams;
final long numOutStreams;
if (isSimple) {
numInStreams = 1;
numOutStreams = 1;
} else {
numInStreams = readUint64(header);
numOutStreams = readUint64(header);
}
totalInStreams += numInStreams;
totalOutStreams += numOutStreams;
byte[] properties = null;
if (hasAttributes) {
final long propertiesSize = readUint64(header);
properties = new byte[(int) propertiesSize];
get(header, properties);
}
// would need to keep looping as above:
if (moreAlternativeMethods) {
throw new IOException("Alternative methods are unsupported, please report. " + // NOSONAR
"The reference implementation doesn't support them either.");
}
coders[i] = new Coder(decompressionMethodId, numInStreams, numOutStreams, properties);
}
folder.coders = coders;
folder.totalInputStreams = totalInStreams;
folder.totalOutputStreams = totalOutStreams;
final long numBindPairs = totalOutStreams - 1;
final BindPair[] bindPairs = new BindPair[(int) numBindPairs];
for (int i = 0; i < bindPairs.length; i++) {
bindPairs[i] = new BindPair(readUint64(header), readUint64(header));
}
folder.bindPairs = bindPairs;
final long numPackedStreams = totalInStreams - numBindPairs;
final long[] packedStreams = new long[(int) numPackedStreams];
if (numPackedStreams == 1) {
int i;
for (i = 0; i < (int) totalInStreams; i++) {
if (folder.findBindPairForInStream(i) < 0) {
break;
}
}
packedStreams[0] = i;
} else {
for (int i = 0; i < (int) numPackedStreams; i++) {
packedStreams[i] = readUint64(header);
}
}
folder.packedStreams = packedStreams;
return folder;
}
private void readFully(final ByteBuffer buf) throws IOException {
buf.rewind();
IOUtils.readFully(channel, buf);
buf.flip();
}
private void readHeader(final ByteBuffer header, final Archive archive) throws IOException {
final int pos = header.position();
final ArchiveStatistics stats = sanityCheckAndCollectStatistics(header);
stats.assertValidity(maxMemoryLimitKb);
header.position(pos);
int nid = getUnsignedByte(header);
if (nid == NID.kArchiveProperties) {
readArchiveProperties(header);
nid = getUnsignedByte(header);
}
if (nid == NID.kAdditionalStreamsInfo) {
throw new IOException("Additional streams unsupported");
// nid = getUnsignedByte(header);
}
if (nid == NID.kMainStreamsInfo) {
readStreamsInfo(header, archive);
nid = getUnsignedByte(header);
}
if (nid == NID.kFilesInfo) {
readFilesInfo(header, archive);
nid = getUnsignedByte(header);
}
}
private Archive readHeaders(final byte[] password) throws IOException {
final ByteBuffer buf = ByteBuffer.allocate(12 /* signature + 2 bytes version + 4 bytes CRC */).order(ByteOrder.LITTLE_ENDIAN);
readFully(buf);
final byte[] signature = new byte[6];
buf.get(signature);
if (!Arrays.equals(signature, sevenZSignature)) {
throw new IOException("Bad 7z signature");
}
// 7zFormat.txt has it wrong - it's first major then minor
final byte archiveVersionMajor = buf.get();
final byte archiveVersionMinor = buf.get();
if (archiveVersionMajor != 0) {
throw new IOException(String.format("Unsupported 7z version (%d,%d)", archiveVersionMajor, archiveVersionMinor));
}
boolean headerLooksValid = false; // See https://www.7-zip.org/recover.html - "There is no correct End Header at the end of archive"
final long startHeaderCrc = 0xffffFFFFL & buf.getInt();
if (startHeaderCrc == 0) {
// This is an indication of a corrupt header - peek the next 20 bytes
final long currentPosition = channel.position();
final ByteBuffer peekBuf = ByteBuffer.allocate(20);
readFully(peekBuf);
channel.position(currentPosition);
// Header invalid if all data is 0
while (peekBuf.hasRemaining()) {
if (peekBuf.get() != 0) {
headerLooksValid = true;
break;
}
}
} else {
headerLooksValid = true;
}
if (headerLooksValid) {
return initializeArchive(readStartHeader(startHeaderCrc), password, true);
}
// No valid header found - probably first file of multipart archive was removed too early. Scan for end header.
if (tryToRecoverBrokenArchives) {
return tryToLocateEndHeader(password);
}
throw new IOException("archive seems to be invalid.\nYou may want to retry and enable the"
+ " tryToRecoverBrokenArchives if the archive could be a multi volume archive that has been closed" + " prematurely.");
}
private void readPackInfo(final ByteBuffer header, final Archive archive) throws IOException {
archive.packPos = readUint64(header);
final int numPackStreamsInt = (int) readUint64(header);
int nid = getUnsignedByte(header);
if (nid == NID.kSize) {
archive.packSizes = new long[numPackStreamsInt];
for (int i = 0; i < archive.packSizes.length; i++) {
archive.packSizes[i] = readUint64(header);
}
nid = getUnsignedByte(header);
}
if (nid == NID.kCRC) {
archive.packCrcsDefined = readAllOrBits(header, numPackStreamsInt);
archive.packCrcs = new long[numPackStreamsInt];
for (int i = 0; i < numPackStreamsInt; i++) {
if (archive.packCrcsDefined.get(i)) {
archive.packCrcs[i] = 0xffffFFFFL & getInt(header);
}
}
nid = getUnsignedByte(header);
}
}
private StartHeader readStartHeader(final long startHeaderCrc) throws IOException {
// using Stream rather than ByteBuffer for the benefit of the
// built-in CRC check
try (DataInputStream dataInputStream = new DataInputStream(
new CRC32VerifyingInputStream(new BoundedSeekableByteChannelInputStream(channel, 20), 20, startHeaderCrc))) {
final long nextHeaderOffset = Long.reverseBytes(dataInputStream.readLong());
if (nextHeaderOffset < 0 || nextHeaderOffset + SIGNATURE_HEADER_SIZE > channel.size()) {
throw new IOException("nextHeaderOffset is out of bounds");
}
final long nextHeaderSize = Long.reverseBytes(dataInputStream.readLong());
final long nextHeaderEnd = nextHeaderOffset + nextHeaderSize;
if (nextHeaderEnd < nextHeaderOffset || nextHeaderEnd + SIGNATURE_HEADER_SIZE > channel.size()) {
throw new IOException("nextHeaderSize is out of bounds");
}
final long nextHeaderCrc = 0xffffFFFFL & Integer.reverseBytes(dataInputStream.readInt());
return new StartHeader(nextHeaderOffset, nextHeaderSize, nextHeaderCrc);
}
}
private void readStreamsInfo(final ByteBuffer header, final Archive archive) throws IOException {
int nid = getUnsignedByte(header);
if (nid == NID.kPackInfo) {
readPackInfo(header, archive);
nid = getUnsignedByte(header);
}
if (nid == NID.kUnpackInfo) {
readUnpackInfo(header, archive);
nid = getUnsignedByte(header);
} else {
// archive without unpack/coders info
archive.folders = Folder.EMPTY_FOLDER_ARRAY;
}
if (nid == NID.kSubStreamsInfo) {
readSubStreamsInfo(header, archive);
nid = getUnsignedByte(header);
}
}
private void readSubStreamsInfo(final ByteBuffer header, final Archive archive) throws IOException {
for (final Folder folder : archive.folders) {
folder.numUnpackSubStreams = 1;
}
long unpackStreamsCount = archive.folders.length;
int nid = getUnsignedByte(header);
if (nid == NID.kNumUnpackStream) {
unpackStreamsCount = 0;
for (final Folder folder : archive.folders) {
final long numStreams = readUint64(header);
folder.numUnpackSubStreams = (int) numStreams;
unpackStreamsCount += numStreams;
}
nid = getUnsignedByte(header);
}
final int totalUnpackStreams = (int) unpackStreamsCount;
final SubStreamsInfo subStreamsInfo = new SubStreamsInfo(totalUnpackStreams);
int nextUnpackStream = 0;
for (final Folder folder : archive.folders) {
if (folder.numUnpackSubStreams == 0) {
continue;
}
long sum = 0;
if (nid == NID.kSize) {
for (int i = 0; i < folder.numUnpackSubStreams - 1; i++) {
final long size = readUint64(header);
subStreamsInfo.unpackSizes[nextUnpackStream++] = size;
sum += size;
}
}
if (sum > folder.getUnpackSize()) {
throw new IOException("sum of unpack sizes of folder exceeds total unpack size");
}
subStreamsInfo.unpackSizes[nextUnpackStream++] = folder.getUnpackSize() - sum;
}
if (nid == NID.kSize) {
nid = getUnsignedByte(header);
}
int numDigests = 0;
for (final Folder folder : archive.folders) {
if (folder.numUnpackSubStreams != 1 || !folder.hasCrc) {
numDigests += folder.numUnpackSubStreams;
}
}
if (nid == NID.kCRC) {
final BitSet hasMissingCrc = readAllOrBits(header, numDigests);
final long[] missingCrcs = new long[numDigests];
for (int i = 0; i < numDigests; i++) {
if (hasMissingCrc.get(i)) {
missingCrcs[i] = 0xffffFFFFL & getInt(header);
}
}
int nextCrc = 0;
int nextMissingCrc = 0;
for (final Folder folder : archive.folders) {
if (folder.numUnpackSubStreams == 1 && folder.hasCrc) {
subStreamsInfo.hasCrc.set(nextCrc, true);
subStreamsInfo.crcs[nextCrc] = folder.crc;
++nextCrc;
} else {
for (int i = 0; i < folder.numUnpackSubStreams; i++) {
subStreamsInfo.hasCrc.set(nextCrc, hasMissingCrc.get(nextMissingCrc));
subStreamsInfo.crcs[nextCrc] = missingCrcs[nextMissingCrc];
++nextCrc;
++nextMissingCrc;
}
}
}
nid = getUnsignedByte(header);
}
archive.subStreamsInfo = subStreamsInfo;
}
private void readUnpackInfo(final ByteBuffer header, final Archive archive) throws IOException {
int nid = getUnsignedByte(header);
final int numFoldersInt = (int) readUint64(header);
final Folder[] folders = new Folder[numFoldersInt];
archive.folders = folders;
/* final int external = */ getUnsignedByte(header);
for (int i = 0; i < numFoldersInt; i++) {
folders[i] = readFolder(header);
}
nid = getUnsignedByte(header);
for (final Folder folder : folders) {
assertFitsIntoNonNegativeInt("totalOutputStreams", folder.totalOutputStreams);
folder.unpackSizes = new long[(int) folder.totalOutputStreams];
for (int i = 0; i < folder.totalOutputStreams; i++) {
folder.unpackSizes[i] = readUint64(header);
}
}
nid = getUnsignedByte(header);
if (nid == NID.kCRC) {
final BitSet crcsDefined = readAllOrBits(header, numFoldersInt);
for (int i = 0; i < numFoldersInt; i++) {
if (crcsDefined.get(i)) {
folders[i].hasCrc = true;
folders[i].crc = 0xffffFFFFL & getInt(header);
} else {
folders[i].hasCrc = false;
}
}
nid = getUnsignedByte(header);
}
}
/**
* Discard any queued streams/ folder stream, and reopen the current folder input stream.
*
* @param folderIndex the index of the folder to reopen
* @param file the 7z entry to read
* @throws IOException if exceptions occur when reading the 7z file
*/
private void reopenFolderInputStream(final int folderIndex, final SevenZArchiveEntry file) throws IOException {
deferredBlockStreams.clear();
if (currentFolderInputStream != null) {
currentFolderInputStream.close();
currentFolderInputStream = null;
}
final Folder folder = archive.folders[folderIndex];
final int firstPackStreamIndex = archive.streamMap.folderFirstPackStreamIndex[folderIndex];
final long folderOffset = SIGNATURE_HEADER_SIZE + archive.packPos + archive.streamMap.packStreamOffsets[firstPackStreamIndex];
currentFolderInputStream = buildDecoderStack(folder, folderOffset, firstPackStreamIndex, file);
}
private ArchiveStatistics sanityCheckAndCollectStatistics(final ByteBuffer header) throws IOException {
final ArchiveStatistics stats = new ArchiveStatistics();
int nid = getUnsignedByte(header);
if (nid == NID.kArchiveProperties) {
sanityCheckArchiveProperties(header);
nid = getUnsignedByte(header);
}
if (nid == NID.kAdditionalStreamsInfo) {
throw new IOException("Additional streams unsupported");
// nid = getUnsignedByte(header);
}
if (nid == NID.kMainStreamsInfo) {
sanityCheckStreamsInfo(header, stats);
nid = getUnsignedByte(header);
}
if (nid == NID.kFilesInfo) {
sanityCheckFilesInfo(header, stats);
nid = getUnsignedByte(header);
}
if (nid != NID.kEnd) {
throw new IOException("Badly terminated header, found " + nid);
}
return stats;
}
private void sanityCheckArchiveProperties(final ByteBuffer header) throws IOException {
int nid = getUnsignedByte(header);
while (nid != NID.kEnd) {
final int propertySize = assertFitsIntoNonNegativeInt("propertySize", readUint64(header));
if (skipBytesFully(header, propertySize) < propertySize) {
throw new IOException("invalid property size");
}
nid = getUnsignedByte(header);
}
}
private void sanityCheckFilesInfo(final ByteBuffer header, final ArchiveStatistics stats) throws IOException {
stats.numberOfEntries = assertFitsIntoNonNegativeInt("numFiles", readUint64(header));
int emptyStreams = -1;
while (true) {
final int propertyType = getUnsignedByte(header);
if (propertyType == 0) {
break;
}
final long size = readUint64(header);
switch (propertyType) {
case NID.kEmptyStream: {
emptyStreams = readBits(header, stats.numberOfEntries).cardinality();
break;
}
case NID.kEmptyFile: {
if (emptyStreams == -1) {
throw new IOException("Header format error: kEmptyStream must appear before kEmptyFile");
}
readBits(header, emptyStreams);
break;
}
case NID.kAnti: {
if (emptyStreams == -1) {
throw new IOException("Header format error: kEmptyStream must appear before kAnti");
}
readBits(header, emptyStreams);
break;
}
case NID.kName: {
final int external = getUnsignedByte(header);
if (external != 0) {
throw new IOException("Not implemented");
}
final int namesLength = assertFitsIntoNonNegativeInt("file names length", size - 1);
if ((namesLength & 1) != 0) {
throw new IOException("File names length invalid");
}
int filesSeen = 0;
for (int i = 0; i < namesLength; i += 2) {
final char c = getChar(header);
if (c == 0) {
filesSeen++;
}
}
if (filesSeen != stats.numberOfEntries) {
throw new IOException("Invalid number of file names (" + filesSeen + " instead of " + stats.numberOfEntries + ")");
}
break;
}
case NID.kCTime: {
final int timesDefined = readAllOrBits(header, stats.numberOfEntries).cardinality();
final int external = getUnsignedByte(header);
if (external != 0) {
throw new IOException("Not implemented");
}
if (skipBytesFully(header, 8 * timesDefined) < 8 * timesDefined) {
throw new IOException("invalid creation dates size");
}
break;
}
case NID.kATime: {
final int timesDefined = readAllOrBits(header, stats.numberOfEntries).cardinality();
final int external = getUnsignedByte(header);
if (external != 0) {
throw new IOException("Not implemented");
}
if (skipBytesFully(header, 8 * timesDefined) < 8 * timesDefined) {
throw new IOException("invalid access dates size");
}
break;
}
case NID.kMTime: {
final int timesDefined = readAllOrBits(header, stats.numberOfEntries).cardinality();
final int external = getUnsignedByte(header);
if (external != 0) {
throw new IOException("Not implemented");
}
if (skipBytesFully(header, 8 * timesDefined) < 8 * timesDefined) {
throw new IOException("invalid modification dates size");
}
break;
}
case NID.kWinAttributes: {
final int attributesDefined = readAllOrBits(header, stats.numberOfEntries).cardinality();
final int external = getUnsignedByte(header);
if (external != 0) {
throw new IOException("Not implemented");
}
if (skipBytesFully(header, 4 * attributesDefined) < 4 * attributesDefined) {
throw new IOException("invalid windows attributes size");
}
break;
}
case NID.kStartPos: {
throw new IOException("kStartPos is unsupported, please report");
}
case NID.kDummy: {
// 7z 9.20 asserts the content is all zeros and ignores the property
// Compress up to 1.8.1 would throw an exception, now we ignore it (see COMPRESS-287
if (skipBytesFully(header, size) < size) {
throw new IOException("Incomplete kDummy property");
}
break;
}
default: {
// Compress up to 1.8.1 would throw an exception, now we ignore it (see COMPRESS-287
if (skipBytesFully(header, size) < size) {
throw new IOException("Incomplete property of type " + propertyType);
}
break;
}
}
}
stats.numberOfEntriesWithStream = stats.numberOfEntries - Math.max(emptyStreams, 0);
}
private int sanityCheckFolder(final ByteBuffer header, final ArchiveStatistics stats) throws IOException {
final int numCoders = assertFitsIntoNonNegativeInt("numCoders", readUint64(header));
if (numCoders == 0) {
throw new IOException("Folder without coders");
}
stats.numberOfCoders += numCoders;
long totalOutStreams = 0;
long totalInStreams = 0;
for (int i = 0; i < numCoders; i++) {
final int bits = getUnsignedByte(header);
final int idSize = bits & 0xf;
get(header, new byte[idSize]);
final boolean isSimple = (bits & 0x10) == 0;
final boolean hasAttributes = (bits & 0x20) != 0;
final boolean moreAlternativeMethods = (bits & 0x80) != 0;
if (moreAlternativeMethods) {
throw new IOException("Alternative methods are unsupported, please report. " + // NOSONAR
"The reference implementation doesn't support them either.");
}
if (isSimple) {
totalInStreams++;
totalOutStreams++;
} else {
totalInStreams += assertFitsIntoNonNegativeInt("numInStreams", readUint64(header));
totalOutStreams += assertFitsIntoNonNegativeInt("numOutStreams", readUint64(header));
}
if (hasAttributes) {
final int propertiesSize = assertFitsIntoNonNegativeInt("propertiesSize", readUint64(header));
if (skipBytesFully(header, propertiesSize) < propertiesSize) {
throw new IOException("invalid propertiesSize in folder");
}
}
}
assertFitsIntoNonNegativeInt("totalInStreams", totalInStreams);
assertFitsIntoNonNegativeInt("totalOutStreams", totalOutStreams);
stats.numberOfOutStreams += totalOutStreams;
stats.numberOfInStreams += totalInStreams;
if (totalOutStreams == 0) {
throw new IOException("Total output streams can't be 0");
}
final int numBindPairs = assertFitsIntoNonNegativeInt("numBindPairs", totalOutStreams - 1);
if (totalInStreams < numBindPairs) {
throw new IOException("Total input streams can't be less than the number of bind pairs");
}
final BitSet inStreamsBound = new BitSet((int) totalInStreams);
for (int i = 0; i < numBindPairs; i++) {
final int inIndex = assertFitsIntoNonNegativeInt("inIndex", readUint64(header));
if (totalInStreams <= inIndex) {
throw new IOException("inIndex is bigger than number of inStreams");
}
inStreamsBound.set(inIndex);
final int outIndex = assertFitsIntoNonNegativeInt("outIndex", readUint64(header));
if (totalOutStreams <= outIndex) {
throw new IOException("outIndex is bigger than number of outStreams");
}
}
final int numPackedStreams = assertFitsIntoNonNegativeInt("numPackedStreams", totalInStreams - numBindPairs);
if (numPackedStreams == 1) {
if (inStreamsBound.nextClearBit(0) == -1) {
throw new IOException("Couldn't find stream's bind pair index");
}
} else {
for (int i = 0; i < numPackedStreams; i++) {
final int packedStreamIndex = assertFitsIntoNonNegativeInt("packedStreamIndex", readUint64(header));
if (packedStreamIndex >= totalInStreams) {
throw new IOException("packedStreamIndex is bigger than number of totalInStreams");
}
}
}
return (int) totalOutStreams;
}
private void sanityCheckPackInfo(final ByteBuffer header, final ArchiveStatistics stats) throws IOException {
final long packPos = readUint64(header);
if (packPos < 0 || SIGNATURE_HEADER_SIZE + packPos > channel.size() || SIGNATURE_HEADER_SIZE + packPos < 0) {
throw new IOException("packPos (" + packPos + ") is out of range");
}
final long numPackStreams = readUint64(header);
stats.numberOfPackedStreams = assertFitsIntoNonNegativeInt("numPackStreams", numPackStreams);
int nid = getUnsignedByte(header);
if (nid == NID.kSize) {
long totalPackSizes = 0;
for (int i = 0; i < stats.numberOfPackedStreams; i++) {
final long packSize = readUint64(header);
totalPackSizes += packSize;
final long endOfPackStreams = SIGNATURE_HEADER_SIZE + packPos + totalPackSizes;
if (packSize < 0 || endOfPackStreams > channel.size() || endOfPackStreams < packPos) {
throw new IOException("packSize (" + packSize + ") is out of range");
}
}
nid = getUnsignedByte(header);
}
if (nid == NID.kCRC) {
final int crcsDefined = readAllOrBits(header, stats.numberOfPackedStreams).cardinality();
if (skipBytesFully(header, 4 * crcsDefined) < 4 * crcsDefined) {
throw new IOException("invalid number of CRCs in PackInfo");
}
nid = getUnsignedByte(header);
}
if (nid != NID.kEnd) {
throw new IOException("Badly terminated PackInfo (" + nid + ")");
}
}
private void sanityCheckStreamsInfo(final ByteBuffer header, final ArchiveStatistics stats) throws IOException {
int nid = getUnsignedByte(header);
if (nid == NID.kPackInfo) {
sanityCheckPackInfo(header, stats);
nid = getUnsignedByte(header);
}
if (nid == NID.kUnpackInfo) {
sanityCheckUnpackInfo(header, stats);
nid = getUnsignedByte(header);
}
if (nid == NID.kSubStreamsInfo) {
sanityCheckSubStreamsInfo(header, stats);
nid = getUnsignedByte(header);
}
if (nid != NID.kEnd) {
throw new IOException("Badly terminated StreamsInfo");
}
}
private void sanityCheckSubStreamsInfo(final ByteBuffer header, final ArchiveStatistics stats) throws IOException {
int nid = getUnsignedByte(header);
final List numUnpackSubStreamsPerFolder = new LinkedList<>();
if (nid == NID.kNumUnpackStream) {
for (int i = 0; i < stats.numberOfFolders; i++) {
numUnpackSubStreamsPerFolder.add(assertFitsIntoNonNegativeInt("numStreams", readUint64(header)));
}
stats.numberOfUnpackSubStreams = numUnpackSubStreamsPerFolder.stream().mapToLong(Integer::longValue).sum();
nid = getUnsignedByte(header);
} else {
stats.numberOfUnpackSubStreams = stats.numberOfFolders;
}
assertFitsIntoNonNegativeInt("totalUnpackStreams", stats.numberOfUnpackSubStreams);
if (nid == NID.kSize) {
for (final int numUnpackSubStreams : numUnpackSubStreamsPerFolder) {
if (numUnpackSubStreams == 0) {
continue;
}
for (int i = 0; i < numUnpackSubStreams - 1; i++) {
final long size = readUint64(header);
if (size < 0) {
throw new IOException("negative unpackSize");
}
}
}
nid = getUnsignedByte(header);
}
int numDigests = 0;
if (numUnpackSubStreamsPerFolder.isEmpty()) {
numDigests = stats.folderHasCrc == null ? stats.numberOfFolders : stats.numberOfFolders - stats.folderHasCrc.cardinality();
} else {
int folderIdx = 0;
for (final int numUnpackSubStreams : numUnpackSubStreamsPerFolder) {
if (numUnpackSubStreams != 1 || stats.folderHasCrc == null || !stats.folderHasCrc.get(folderIdx++)) {
numDigests += numUnpackSubStreams;
}
}
}
if (nid == NID.kCRC) {
assertFitsIntoNonNegativeInt("numDigests", numDigests);
final int missingCrcs = readAllOrBits(header, numDigests).cardinality();
if (skipBytesFully(header, 4 * missingCrcs) < 4 * missingCrcs) {
throw new IOException("invalid number of missing CRCs in SubStreamInfo");
}
nid = getUnsignedByte(header);
}
if (nid != NID.kEnd) {
throw new IOException("Badly terminated SubStreamsInfo");
}
}
private void sanityCheckUnpackInfo(final ByteBuffer header, final ArchiveStatistics stats) throws IOException {
int nid = getUnsignedByte(header);
if (nid != NID.kFolder) {
throw new IOException("Expected kFolder, got " + nid);
}
final long numFolders = readUint64(header);
stats.numberOfFolders = assertFitsIntoNonNegativeInt("numFolders", numFolders);
final int external = getUnsignedByte(header);
if (external != 0) {
throw new IOException("External unsupported");
}
final List numberOfOutputStreamsPerFolder = new LinkedList<>();
for (int i = 0; i < stats.numberOfFolders; i++) {
numberOfOutputStreamsPerFolder.add(sanityCheckFolder(header, stats));
}
final long totalNumberOfBindPairs = stats.numberOfOutStreams - stats.numberOfFolders;
final long packedStreamsRequiredByFolders = stats.numberOfInStreams - totalNumberOfBindPairs;
if (packedStreamsRequiredByFolders < stats.numberOfPackedStreams) {
throw new IOException("archive doesn't contain enough packed streams");
}
nid = getUnsignedByte(header);
if (nid != NID.kCodersUnpackSize) {
throw new IOException("Expected kCodersUnpackSize, got " + nid);
}
for (final int numberOfOutputStreams : numberOfOutputStreamsPerFolder) {
for (int i = 0; i < numberOfOutputStreams; i++) {
final long unpackSize = readUint64(header);
if (unpackSize < 0) {
throw new IllegalArgumentException("negative unpackSize");
}
}
}
nid = getUnsignedByte(header);
if (nid == NID.kCRC) {
stats.folderHasCrc = readAllOrBits(header, stats.numberOfFolders);
final int crcsDefined = stats.folderHasCrc.cardinality();
if (skipBytesFully(header, 4 * crcsDefined) < 4 * crcsDefined) {
throw new IOException("invalid number of CRCs in UnpackInfo");
}
nid = getUnsignedByte(header);
}
if (nid != NID.kEnd) {
throw new IOException("Badly terminated UnpackInfo");
}
}
/**
* Skips all the entries if needed. Entries need to be skipped when:
*
* 1. it's a random access 2. one of these 2 condition is meet :
*
*
* 2.1 currentEntryIndex != entryIndex : this means there are some entries to be skipped(currentEntryIndex < entryIndex) or the entry has already been
* read(currentEntryIndex > entryIndex)
*
*
* 2.2 currentEntryIndex == entryIndex && !hasCurrentEntryBeenRead: if the entry to be read is the current entry, but some data of it has been read before,
* then we need to reopen the stream of the folder and skip all the entries before the current entries
*
*
* @param entryIndex the entry to be read
* @param isInSameFolder are the entry to be read and the current entry in the same folder
* @param folderIndex the index of the folder which contains the entry
* @return true if there are entries actually skipped
* @throws IOException there are exceptions when skipping entries
* @since 1.21
*/
private boolean skipEntriesWhenNeeded(final int entryIndex, final boolean isInSameFolder, final int folderIndex) throws IOException {
final SevenZArchiveEntry file = archive.files[entryIndex];
// if the entry to be read is the current entry, and the entry has not
// been read yet, then there's nothing we need to do
if (currentEntryIndex == entryIndex && !hasCurrentEntryBeenRead()) {
return false;
}
// 1. if currentEntryIndex < entryIndex :
// this means there are some entries to be skipped(currentEntryIndex < entryIndex)
// 2. if currentEntryIndex > entryIndex || (currentEntryIndex == entryIndex && hasCurrentEntryBeenRead) :
// this means the entry has already been read before, and we need to reopen the
// stream of the folder and skip all the entries before the current entries
int filesToSkipStartIndex = archive.streamMap.folderFirstFileIndex[currentFolderIndex];
if (isInSameFolder) {
if (currentEntryIndex < entryIndex) {
// the entries between filesToSkipStartIndex and currentEntryIndex had already been skipped
filesToSkipStartIndex = currentEntryIndex + 1;
} else {
// the entry is in the same folder of current entry, but it has already been read before, we need to reset
// the position of the currentFolderInputStream to the beginning of folder, and then skip the files
// from the start entry of the folder again
reopenFolderInputStream(folderIndex, file);
}
}
for (int i = filesToSkipStartIndex; i < entryIndex; i++) {
final SevenZArchiveEntry fileToSkip = archive.files[i];
InputStream fileStreamToSkip = new BoundedInputStream(currentFolderInputStream, fileToSkip.getSize());
if (fileToSkip.getHasCrc()) {
fileStreamToSkip = new CRC32VerifyingInputStream(fileStreamToSkip, fileToSkip.getSize(), fileToSkip.getCrcValue());
}
deferredBlockStreams.add(fileStreamToSkip);
// set the content methods as well, it equals to file.getContentMethods() because they are in same folder
fileToSkip.setContentMethods(file.getContentMethods());
}
return true;
}
@Override
public String toString() {
return archive.toString();
}
private Archive tryToLocateEndHeader(final byte[] password) throws IOException {
final ByteBuffer nidBuf = ByteBuffer.allocate(1);
final long searchLimit = 1024L * 1024 * 1;
// Main header, plus bytes that readStartHeader would read
final long previousDataSize = channel.position() + 20;
final long minPos;
// Determine minimal position - can't start before current position
if (channel.position() + searchLimit > channel.size()) {
minPos = channel.position();
} else {
minPos = channel.size() - searchLimit;
}
long pos = channel.size() - 1;
// Loop: Try from end of archive
while (pos > minPos) {
pos--;
channel.position(pos);
nidBuf.rewind();
if (channel.read(nidBuf) < 1) {
throw new EOFException();
}
final int nid = nidBuf.array()[0];
// First indicator: Byte equals one of these header identifiers
if (nid == NID.kEncodedHeader || nid == NID.kHeader) {
try {
// Try to initialize Archive structure from here
final long nextHeaderOffset = pos - previousDataSize;
final long nextHeaderSize = channel.size() - pos;
final StartHeader startHeader = new StartHeader(nextHeaderOffset, nextHeaderSize, 0);
final Archive result = initializeArchive(startHeader, password, false);
// Sanity check: There must be some data...
if (result.packSizes.length > 0 && result.files.length > 0) {
return result;
}
} catch (final Exception ignore) {
// Wrong guess...
}
}
}
throw new IOException("Start header corrupt and unable to guess end header");
}
}
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