org.apache.commons.compress.archivers.sevenz.SevenZFile Maven / Gradle / Ivy
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Apache Commons Compress software 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");
}
}