+++ /dev/null
-/*
- * Copyright (C) 2011 The Android Open Source Project Licensed 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.lineageos.eleven.cache;
-
-import java.io.BufferedInputStream;
-import java.io.BufferedWriter;
-import java.io.Closeable;
-import java.io.EOFException;
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileNotFoundException;
-import java.io.FileOutputStream;
-import java.io.FileWriter;
-import java.io.FilterOutputStream;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.InputStreamReader;
-import java.io.OutputStream;
-import java.io.OutputStreamWriter;
-import java.io.Reader;
-import java.io.StringWriter;
-import java.io.Writer;
-import java.lang.reflect.Array;
-import java.nio.charset.Charset;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Iterator;
-import java.util.LinkedHashMap;
-import java.util.Map;
-import java.util.concurrent.Callable;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.LinkedBlockingQueue;
-import java.util.concurrent.ThreadPoolExecutor;
-import java.util.concurrent.TimeUnit;
-
-/**
- ****************************************************************************** Taken from the JB source code, can be found in:
- * libcore/luni/src/main/java/libcore/io/DiskLruCache.java or direct link:
- * https:
- * //android.googlesource.com/platform/libcore/+/android-4.1.1_r1/luni/src/
- * main/java/libcore/io/DiskLruCache.java A cache that uses a bounded amount of
- * space on a filesystem. Each cache entry has a string key and a fixed number
- * of values. Values are byte sequences, accessible as streams or files. Each
- * value must be between {@code 0} and {@code Integer.MAX_VALUE} bytes in
- * length.
- * <p>
- * The cache stores its data in a directory on the filesystem. This directory
- * must be exclusive to the cache; the cache may delete or overwrite files from
- * its directory. It is an error for multiple processes to use the same cache
- * directory at the same time.
- * <p>
- * This cache limits the number of bytes that it will store on the filesystem.
- * When the number of stored bytes exceeds the limit, the cache will remove
- * entries in the background until the limit is satisfied. The limit is not
- * strict: the cache may temporarily exceed it while waiting for files to be
- * deleted. The limit does not include filesystem overhead or the cache journal
- * so space-sensitive applications should set a conservative limit.
- * <p>
- * Clients call {@link #edit} to create or update the values of an entry. An
- * entry may have only one editor at one time; if a value is not available to be
- * edited then {@link #edit} will return null.
- * <ul>
- * <li>When an entry is being <strong>created</strong> it is necessary to supply
- * a full set of values; the empty value should be used as a placeholder if
- * necessary.
- * <li>When an entry is being <strong>edited</strong>, it is not necessary to
- * supply data for every value; values default to their previous value.
- * </ul>
- * Every {@link #edit} call must be matched by a call to {@link Editor#commit}
- * or {@link Editor#abort}. Committing is atomic: a read observes the full set
- * of values as they were before or after the commit, but never a mix of values.
- * <p>
- * Clients call {@link #get} to read a snapshot of an entry. The read will
- * observe the value at the time that {@link #get} was called. Updates and
- * removals after the call do not impact ongoing reads.
- * <p>
- * This class is tolerant of some I/O errors. If files are missing from the
- * filesystem, the corresponding entries will be dropped from the cache. If an
- * error occurs while writing a cache value, the edit will fail silently.
- * Callers should handle other problems by catching {@code IOException} and
- * responding appropriately.
- */
-public final class DiskLruCache implements Closeable {
- static final String JOURNAL_FILE = "journal";
-
- static final String JOURNAL_FILE_TMP = "journal.tmp";
-
- static final String MAGIC = "libcore.io.DiskLruCache";
-
- static final String VERSION_1 = "1";
-
- static final long ANY_SEQUENCE_NUMBER = -1;
-
- private static final String CLEAN = "CLEAN";
-
- private static final String DIRTY = "DIRTY";
-
- private static final String REMOVE = "REMOVE";
-
- private static final String READ = "READ";
-
- private static final Charset UTF_8 = Charset.forName("UTF-8");
-
- private static final int IO_BUFFER_SIZE = 8 * 1024;
-
- /*
- * This cache uses a journal file named "journal". A typical journal file
- * looks like this: libcore.io.DiskLruCache 1 100 2 CLEAN
- * 3400330d1dfc7f3f7f4b8d4d803dfcf6 832 21054 DIRTY
- * 335c4c6028171cfddfbaae1a9c313c52 CLEAN 335c4c6028171cfddfbaae1a9c313c52
- * 3934 2342 REMOVE 335c4c6028171cfddfbaae1a9c313c52 DIRTY
- * 1ab96a171faeeee38496d8b330771a7a CLEAN 1ab96a171faeeee38496d8b330771a7a
- * 1600 234 READ 335c4c6028171cfddfbaae1a9c313c52 READ
- * 3400330d1dfc7f3f7f4b8d4d803dfcf6 The first five lines of the journal form
- * its header. They are the constant string "libcore.io.DiskLruCache", the
- * disk cache's version, the application's version, the value count, and a
- * blank line. Each of the subsequent lines in the file is a record of the
- * state of a cache entry. Each line contains space-separated values: a
- * state, a key, and optional state-specific values. o DIRTY lines track
- * that an entry is actively being created or updated. Every successful
- * DIRTY action should be followed by a CLEAN or REMOVE action. DIRTY lines
- * without a matching CLEAN or REMOVE indicate that temporary files may need
- * to be deleted. o CLEAN lines track a cache entry that has been
- * successfully published and may be read. A publish line is followed by the
- * lengths of each of its values. o READ lines track accesses for LRU. o
- * REMOVE lines track entries that have been deleted. The journal file is
- * appended to as cache operations occur. The journal may occasionally be
- * compacted by dropping redundant lines. A temporary file named
- * "journal.tmp" will be used during compaction; that file should be deleted
- * if it exists when the cache is opened.
- */
-
- private final File directory;
-
- private final File journalFile;
-
- private final File journalFileTmp;
-
- private final int appVersion;
-
- private final long maxSize;
-
- private final int valueCount;
-
- private long size = 0;
-
- private Writer journalWriter;
-
- private final LinkedHashMap<String, Entry> lruEntries = new LinkedHashMap<>(0,
- 0.75f, true);
-
- private int redundantOpCount;
-
- /**
- * To differentiate between old and current snapshots, each entry is given a
- * sequence number each time an edit is committed. A snapshot is stale if
- * its sequence number is not equal to its entry's sequence number.
- */
- private long nextSequenceNumber = 0;
-
- /* From java.util.Arrays */
- @SuppressWarnings("unchecked")
- private static <T> T[] copyOfRange(final T[] original, final int start, final int end) {
- final int originalLength = original.length; // For exception priority
- // compatibility.
- if (start > end) {
- throw new IllegalArgumentException();
- }
- if (start < 0 || start > originalLength) {
- throw new ArrayIndexOutOfBoundsException();
- }
- final int resultLength = end - start;
- final int copyLength = Math.min(resultLength, originalLength - start);
- final T[] result = (T[])Array.newInstance(original.getClass().getComponentType(),
- resultLength);
- System.arraycopy(original, start, result, 0, copyLength);
- return result;
- }
-
- /**
- * Returns the remainder of 'reader' as a string, closing it when done.
- */
- public static String readFully(final Reader reader) throws IOException {
- try {
- final StringWriter writer = new StringWriter();
- final char[] buffer = new char[1024];
- int count;
- while ((count = reader.read(buffer)) != -1) {
- writer.write(buffer, 0, count);
- }
- return writer.toString();
- } finally {
- reader.close();
- }
- }
-
- /**
- * Returns the ASCII characters up to but not including the next "\r\n", or
- * "\n".
- *
- * @throws java.io.EOFException if the stream is exhausted before the next
- * newline character.
- */
- public static String readAsciiLine(final InputStream in) throws IOException {
- // TODO: support UTF-8 here instead
-
- final StringBuilder result = new StringBuilder(80);
- while (true) {
- final int c = in.read();
- if (c == -1) {
- throw new EOFException();
- } else if (c == '\n') {
- break;
- }
-
- result.append((char)c);
- }
- final int length = result.length();
- if (length > 0 && result.charAt(length - 1) == '\r') {
- result.setLength(length - 1);
- }
- return result.toString();
- }
-
- /**
- * Closes 'closeable', ignoring any checked exceptions. Does nothing if
- * 'closeable' is null.
- */
- public static void closeQuietly(final Closeable closeable) {
- if (closeable != null) {
- try {
- closeable.close();
- } catch (final RuntimeException rethrown) {
- throw rethrown;
- } catch (final Exception ignored) {
- }
- }
- }
-
- /**
- * Recursively delete everything in {@code dir}.
- */
- // TODO: this should specify paths as Strings rather than as Files
- public static void deleteContents(final File dir) throws IOException {
- final File[] files = dir.listFiles();
- if (files == null) {
- throw new IllegalArgumentException("not a directory: " + dir);
- }
- for (final File file : files) {
- if (file.isDirectory()) {
- deleteContents(file);
- }
- if (!file.delete()) {
- throw new IOException("failed to delete file: " + file);
- }
- }
- }
-
- /** This cache uses a single background thread to evict entries. */
- private final ExecutorService executorService = new ThreadPoolExecutor(0, 1, 60L,
- TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>());
-
- private final Callable<Void> cleanupCallable = new Callable<Void>() {
- @Override
- public Void call() throws Exception {
- synchronized (DiskLruCache.this) {
- if (journalWriter == null) {
- return null; // closed
- }
- trimToSize();
- if (journalRebuildRequired()) {
- rebuildJournal();
- redundantOpCount = 0;
- }
- }
- return null;
- }
- };
-
- private DiskLruCache(final File directory, final int appVersion, final int valueCount,
- final long maxSize) {
- this.directory = directory;
- this.appVersion = appVersion;
- journalFile = new File(directory, JOURNAL_FILE);
- journalFileTmp = new File(directory, JOURNAL_FILE_TMP);
- this.valueCount = valueCount;
- this.maxSize = maxSize;
- }
-
- /**
- * Opens the cache in {@code directory}, creating a cache if none exists
- * there.
- *
- * @param directory a writable directory
- * @param appVersion
- * @param valueCount the number of values per cache entry. Must be positive.
- * @param maxSize the maximum number of bytes this cache should use to store
- * @throws IOException if reading or writing the cache directory fails
- */
- public static DiskLruCache open(final File directory, final int appVersion,
- final int valueCount, final long maxSize) throws IOException {
- if (maxSize <= 0) {
- throw new IllegalArgumentException("maxSize <= 0");
- }
- if (valueCount <= 0) {
- throw new IllegalArgumentException("valueCount <= 0");
- }
-
- // prefer to pick up where we left off
- DiskLruCache cache = new DiskLruCache(directory, appVersion, valueCount, maxSize);
- if (cache.journalFile.exists()) {
- try {
- cache.readJournal();
- cache.processJournal();
- cache.journalWriter = new BufferedWriter(new FileWriter(cache.journalFile, true),
- IO_BUFFER_SIZE);
- return cache;
- } catch (final IOException journalIsCorrupt) {
- // System.logW("DiskLruCache " + directory + " is corrupt: "
- // + journalIsCorrupt.getMessage() + ", removing");
- cache.delete();
- }
- }
-
- // create a new empty cache
- directory.mkdirs();
- cache = new DiskLruCache(directory, appVersion, valueCount, maxSize);
- cache.rebuildJournal();
- return cache;
- }
-
- private void readJournal() throws IOException {
- final InputStream in = new BufferedInputStream(new FileInputStream(journalFile),
- IO_BUFFER_SIZE);
- try {
- final String magic = readAsciiLine(in);
- final String version = readAsciiLine(in);
- final String appVersionString = readAsciiLine(in);
- final String valueCountString = readAsciiLine(in);
- final String blank = readAsciiLine(in);
- if (!MAGIC.equals(magic) || !VERSION_1.equals(version)
- || !Integer.toString(appVersion).equals(appVersionString)
- || !Integer.toString(valueCount).equals(valueCountString) || !"".equals(blank)) {
- throw new IOException("unexpected journal header: [" + magic + ", " + version
- + ", " + valueCountString + ", " + blank + "]");
- }
-
- while (true) {
- try {
- readJournalLine(readAsciiLine(in));
- } catch (final EOFException endOfJournal) {
- break;
- }
- }
- } finally {
- closeQuietly(in);
- }
- }
-
- private void readJournalLine(final String line) throws IOException {
- final String[] parts = line.split(" ");
- if (parts.length < 2) {
- throw new IOException("unexpected journal line: " + line);
- }
-
- final String key = parts[1];
- if (parts[0].equals(REMOVE) && parts.length == 2) {
- lruEntries.remove(key);
- return;
- }
-
- Entry entry = lruEntries.get(key);
- if (entry == null) {
- entry = new Entry(key);
- lruEntries.put(key, entry);
- }
-
- if (parts[0].equals(CLEAN) && parts.length == 2 + valueCount) {
- entry.readable = true;
- entry.currentEditor = null;
- entry.setLengths(copyOfRange(parts, 2, parts.length));
- } else if (parts[0].equals(DIRTY) && parts.length == 2) {
- entry.currentEditor = new Editor(entry);
- } else if (parts[0].equals(READ) && parts.length == 2) {
- // this work was already done by calling lruEntries.get()
- } else {
- throw new IOException("unexpected journal line: " + line);
- }
- }
-
- /**
- * Computes the initial size and collects garbage as a part of opening the
- * cache. Dirty entries are assumed to be inconsistent and will be deleted.
- */
- private void processJournal() throws IOException {
- deleteIfExists(journalFileTmp);
- for (final Iterator<Entry> i = lruEntries.values().iterator(); i.hasNext();) {
- final Entry entry = i.next();
- if (entry.currentEditor == null) {
- for (int t = 0; t < valueCount; t++) {
- size += entry.lengths[t];
- }
- } else {
- entry.currentEditor = null;
- for (int t = 0; t < valueCount; t++) {
- deleteIfExists(entry.getCleanFile(t));
- deleteIfExists(entry.getDirtyFile(t));
- }
- i.remove();
- }
- }
- }
-
- /**
- * Creates a new journal that omits redundant information. This replaces the
- * current journal if it exists.
- */
- private synchronized void rebuildJournal() throws IOException {
- if (journalWriter != null) {
- journalWriter.close();
- }
-
- final Writer writer = new BufferedWriter(new FileWriter(journalFileTmp), IO_BUFFER_SIZE);
- writer.write(MAGIC);
- writer.write("\n");
- writer.write(VERSION_1);
- writer.write("\n");
- writer.write(Integer.toString(appVersion));
- writer.write("\n");
- writer.write(Integer.toString(valueCount));
- writer.write("\n");
- writer.write("\n");
-
- for (final Entry entry : lruEntries.values()) {
- if (entry.currentEditor != null) {
- writer.write(DIRTY + ' ' + entry.key + '\n');
- } else {
- writer.write(CLEAN + ' ' + entry.key + entry.getLengths() + '\n');
- }
- }
-
- writer.close();
- journalFileTmp.renameTo(journalFile);
- journalWriter = new BufferedWriter(new FileWriter(journalFile, true), IO_BUFFER_SIZE);
- }
-
- private static void deleteIfExists(final File file) throws IOException {
- // try {
- // Libcore.os.remove(file.getPath());
- // } catch (ErrnoException errnoException) {
- // if (errnoException.errno != OsConstants.ENOENT) {
- // throw errnoException.rethrowAsIOException();
- // }
- // }
- if (file.exists() && !file.delete()) {
- throw new IOException();
- }
- }
-
- /**
- * Returns a snapshot of the entry named {@code key}, or null if it doesn't
- * exist is not currently readable. If a value is returned, it is moved to
- * the head of the LRU queue.
- */
- public synchronized Snapshot get(final String key) throws IOException {
- checkNotClosed();
- validateKey(key);
- final Entry entry = lruEntries.get(key);
- if (entry == null) {
- return null;
- }
-
- if (!entry.readable) {
- return null;
- }
-
- /*
- * Open all streams eagerly to guarantee that we see a single published
- * snapshot. If we opened streams lazily then the streams could come
- * from different edits.
- */
- final InputStream[] ins = new InputStream[valueCount];
- try {
- for (int i = 0; i < valueCount; i++) {
- ins[i] = new FileInputStream(entry.getCleanFile(i));
- }
- } catch (final FileNotFoundException e) {
- // a file must have been deleted manually!
- return null;
- }
-
- redundantOpCount++;
- journalWriter.append(READ + ' ').append(key).append('\n');
- if (journalRebuildRequired()) {
- executorService.submit(cleanupCallable);
- }
-
- return new Snapshot(key, entry.sequenceNumber, ins);
- }
-
- /**
- * Returns an editor for the entry named {@code key}, or null if another
- * edit is in progress.
- */
- public Editor edit(final String key) throws IOException {
- return edit(key, ANY_SEQUENCE_NUMBER);
- }
-
- private synchronized Editor edit(final String key, final long expectedSequenceNumber)
- throws IOException {
- checkNotClosed();
- validateKey(key);
- Entry entry = lruEntries.get(key);
- if (expectedSequenceNumber != ANY_SEQUENCE_NUMBER
- && (entry == null || entry.sequenceNumber != expectedSequenceNumber)) {
- return null; // snapshot is stale
- }
- if (entry == null) {
- entry = new Entry(key);
- lruEntries.put(key, entry);
- } else if (entry.currentEditor != null) {
- return null; // another edit is in progress
- }
-
- final Editor editor = new Editor(entry);
- entry.currentEditor = editor;
-
- // flush the journal before creating files to prevent file leaks
- journalWriter.write(DIRTY + ' ' + key + '\n');
- journalWriter.flush();
- return editor;
- }
-
- /**
- * Returns the directory where this cache stores its data.
- */
- public File getDirectory() {
- return directory;
- }
-
- /**
- * Returns the maximum number of bytes that this cache should use to store
- * its data.
- */
- public long maxSize() {
- return maxSize;
- }
-
- /**
- * Returns the number of bytes currently being used to store the values in
- * this cache. This may be greater than the max size if a background
- * deletion is pending.
- */
- public synchronized long size() {
- return size;
- }
-
- private synchronized void completeEdit(final Editor editor, final boolean success)
- throws IOException {
- final Entry entry = editor.entry;
- if (entry.currentEditor != editor) {
- throw new IllegalStateException();
- }
-
- // if this edit is creating the entry for the first time, every index
- // must have a value
- if (success && !entry.readable) {
- for (int i = 0; i < valueCount; i++) {
- if (!entry.getDirtyFile(i).exists()) {
- editor.abort();
- throw new IllegalStateException("edit didn't create file " + i);
- }
- }
- }
-
- for (int i = 0; i < valueCount; i++) {
- final File dirty = entry.getDirtyFile(i);
- if (success) {
- if (dirty.exists()) {
- final File clean = entry.getCleanFile(i);
- dirty.renameTo(clean);
- final long oldLength = entry.lengths[i];
- final long newLength = clean.length();
- entry.lengths[i] = newLength;
- size = size - oldLength + newLength;
- }
- } else {
- deleteIfExists(dirty);
- }
- }
-
- redundantOpCount++;
- entry.currentEditor = null;
- if (entry.readable | success) {
- entry.readable = true;
- journalWriter.write(CLEAN + ' ' + entry.key + entry.getLengths() + '\n');
- if (success) {
- entry.sequenceNumber = nextSequenceNumber++;
- }
- } else {
- lruEntries.remove(entry.key);
- journalWriter.write(REMOVE + ' ' + entry.key + '\n');
- }
-
- if (size > maxSize || journalRebuildRequired()) {
- executorService.submit(cleanupCallable);
- }
- }
-
- /**
- * We only rebuild the journal when it will halve the size of the journal
- * and eliminate at least 2000 ops.
- */
- private boolean journalRebuildRequired() {
- final int REDUNDANT_OP_COMPACT_THRESHOLD = 2000;
- return redundantOpCount >= REDUNDANT_OP_COMPACT_THRESHOLD
- && redundantOpCount >= lruEntries.size();
- }
-
- /**
- * Drops the entry for {@code key} if it exists and can be removed. Entries
- * actively being edited cannot be removed.
- *
- * @return true if an entry was removed.
- */
- public synchronized boolean remove(final String key) throws IOException {
- checkNotClosed();
- validateKey(key);
- final Entry entry = lruEntries.get(key);
- if (entry == null || entry.currentEditor != null) {
- return false;
- }
-
- for (int i = 0; i < valueCount; i++) {
- final File file = entry.getCleanFile(i);
- if (!file.delete()) {
- throw new IOException("failed to delete " + file);
- }
- size -= entry.lengths[i];
- entry.lengths[i] = 0;
- }
-
- redundantOpCount++;
- journalWriter.append(REMOVE + ' ').append(key).append('\n');
- lruEntries.remove(key);
-
- if (journalRebuildRequired()) {
- executorService.submit(cleanupCallable);
- }
-
- return true;
- }
-
- /**
- * Returns true if this cache has been closed.
- */
- public boolean isClosed() {
- return journalWriter == null;
- }
-
- private void checkNotClosed() {
- if (journalWriter == null) {
- throw new IllegalStateException("cache is closed");
- }
- }
-
- /**
- * Force buffered operations to the filesystem.
- */
- public synchronized void flush() throws IOException {
- checkNotClosed();
- trimToSize();
- journalWriter.flush();
- }
-
- /**
- * Closes this cache. Stored values will remain on the filesystem.
- */
- @Override
- public synchronized void close() throws IOException {
- if (journalWriter == null) {
- return; // already closed
- }
- for (final Entry entry : new ArrayList<>(lruEntries.values())) {
- if (entry.currentEditor != null) {
- entry.currentEditor.abort();
- }
- }
- trimToSize();
- journalWriter.close();
- journalWriter = null;
- }
-
- private void trimToSize() throws IOException {
- while (size > maxSize) {
- // Map.Entry<String, Entry> toEvict = lruEntries.eldest();
- final Map.Entry<String, Entry> toEvict = lruEntries.entrySet().iterator().next();
- remove(toEvict.getKey());
- }
- }
-
- /**
- * Closes the cache and deletes all of its stored values. This will delete
- * all files in the cache directory including files that weren't created by
- * the cache.
- */
- public void delete() throws IOException {
- close();
- deleteContents(directory);
- }
-
- private void validateKey(final String key) {
- if (key.contains(" ") || key.contains("\n") || key.contains("\r")) {
- throw new IllegalArgumentException("keys must not contain spaces or newlines: \"" + key
- + "\"");
- }
- }
-
- private static String inputStreamToString(final InputStream in) throws IOException {
- return readFully(new InputStreamReader(in, UTF_8));
- }
-
- /**
- * A snapshot of the values for an entry.
- */
- public final class Snapshot implements Closeable {
- private final String key;
-
- private final long sequenceNumber;
-
- private final InputStream[] ins;
-
- private Snapshot(final String key, final long sequenceNumber, final InputStream[] ins) {
- this.key = key;
- this.sequenceNumber = sequenceNumber;
- this.ins = ins;
- }
-
- /**
- * Returns an editor for this snapshot's entry, or null if either the
- * entry has changed since this snapshot was created or if another edit
- * is in progress.
- */
- public Editor edit() throws IOException {
- return DiskLruCache.this.edit(key, sequenceNumber);
- }
-
- /**
- * Returns the unbuffered stream with the value for {@code index}.
- */
- public InputStream getInputStream(final int index) {
- return ins[index];
- }
-
- /**
- * Returns the string value for {@code index}.
- */
- public String getString(final int index) throws IOException {
- return inputStreamToString(getInputStream(index));
- }
-
- @Override
- public void close() {
- for (final InputStream in : ins) {
- closeQuietly(in);
- }
- }
- }
-
- /**
- * Edits the values for an entry.
- */
- public final class Editor {
- private final Entry entry;
-
- private boolean hasErrors;
-
- private Editor(final Entry entry) {
- this.entry = entry;
- }
-
- /**
- * Returns an unbuffered input stream to read the last committed value,
- * or null if no value has been committed.
- */
- public InputStream newInputStream(final int index) throws IOException {
- synchronized (DiskLruCache.this) {
- if (entry.currentEditor != this) {
- throw new IllegalStateException();
- }
- if (!entry.readable) {
- return null;
- }
- return new FileInputStream(entry.getCleanFile(index));
- }
- }
-
- /**
- * Returns the last committed value as a string, or null if no value has
- * been committed.
- */
- public String getString(final int index) throws IOException {
- final InputStream in = newInputStream(index);
- return in != null ? inputStreamToString(in) : null;
- }
-
- /**
- * Returns a new unbuffered output stream to write the value at
- * {@code index}. If the underlying output stream encounters errors when
- * writing to the filesystem, this edit will be aborted when
- * {@link #commit} is called. The returned output stream does not throw
- * IOExceptions.
- */
- public OutputStream newOutputStream(final int index) throws IOException {
- synchronized (DiskLruCache.this) {
- if (entry.currentEditor != this) {
- throw new IllegalStateException();
- }
- return new FaultHidingOutputStream(new FileOutputStream(entry.getDirtyFile(index)));
- }
- }
-
- /**
- * Sets the value at {@code index} to {@code value}.
- */
- public void set(final int index, final String value) throws IOException {
- Writer writer = null;
- try {
- writer = new OutputStreamWriter(newOutputStream(index), UTF_8);
- writer.write(value);
- } finally {
- closeQuietly(writer);
- }
- }
-
- /**
- * Commits this edit so it is visible to readers. This releases the edit
- * lock so another edit may be started on the same key.
- */
- public void commit() throws IOException {
- if (hasErrors) {
- completeEdit(this, false);
- remove(entry.key); // the previous entry is stale
- } else {
- completeEdit(this, true);
- }
- }
-
- /**
- * Aborts this edit. This releases the edit lock so another edit may be
- * started on the same key.
- */
- public void abort() throws IOException {
- completeEdit(this, false);
- }
-
- private class FaultHidingOutputStream extends FilterOutputStream {
- private FaultHidingOutputStream(final OutputStream out) {
- super(out);
- }
-
- @Override
- public void write(final int oneByte) {
- try {
- out.write(oneByte);
- } catch (final IOException e) {
- hasErrors = true;
- }
- }
-
- @Override
- public void write(final byte[] buffer, final int offset, final int length) {
- try {
- out.write(buffer, offset, length);
- } catch (final IOException e) {
- hasErrors = true;
- }
- }
-
- @Override
- public void close() {
- try {
- out.close();
- } catch (final IOException e) {
- hasErrors = true;
- }
- }
-
- @Override
- public void flush() {
- try {
- out.flush();
- } catch (final IOException e) {
- hasErrors = true;
- }
- }
- }
- }
-
- private final class Entry {
- private final String key;
-
- /** Lengths of this entry's files. */
- private final long[] lengths;
-
- /** True if this entry has ever been published */
- private boolean readable;
-
- /** The ongoing edit or null if this entry is not being edited. */
- private Editor currentEditor;
-
- /**
- * The sequence number of the most recently committed edit to this
- * entry.
- */
- private long sequenceNumber;
-
- private Entry(final String key) {
- this.key = key;
- lengths = new long[valueCount];
- }
-
- public String getLengths() throws IOException {
- final StringBuilder result = new StringBuilder();
- for (final long size : lengths) {
- result.append(' ').append(size);
- }
- return result.toString();
- }
-
- /**
- * Set lengths using decimal numbers like "10123".
- */
- private void setLengths(final String[] strings) throws IOException {
- if (strings.length != valueCount) {
- throw invalidLengths(strings);
- }
-
- try {
- for (int i = 0; i < strings.length; i++) {
- lengths[i] = Long.parseLong(strings[i]);
- }
- } catch (final NumberFormatException e) {
- throw invalidLengths(strings);
- }
- }
-
- private IOException invalidLengths(final String[] strings) throws IOException {
- throw new IOException("unexpected journal line: " + Arrays.toString(strings));
- }
-
- public File getCleanFile(final int i) {
- return new File(directory, key + "." + i);
- }
-
- public File getDirtyFile(final int i) {
- return new File(directory, key + "." + i + ".tmp");
- }
- }
-}
import android.os.ParcelFileDescriptor;
import android.util.Log;
+import org.lineageos.eleven.cache.disklrucache.DiskLruCache;
import org.lineageos.eleven.utils.ElevenUtils;
import java.io.File;
--- /dev/null
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed 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.lineageos.eleven.cache.disklrucache;
+
+import java.io.BufferedWriter;
+import java.io.Closeable;
+import java.io.EOFException;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.FilterOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.io.Writer;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.concurrent.Callable;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+/**
+ * A cache that uses a bounded amount of space on a filesystem. Each cache
+ * entry has a string key and a fixed number of values. Each key must match
+ * the regex <strong>[a-z0-9_-]{1,120}</strong>. Values are byte sequences,
+ * accessible as streams or files. Each value must be between {@code 0} and
+ * {@code Integer.MAX_VALUE} bytes in length.
+ *
+ * <p>The cache stores its data in a directory on the filesystem. This
+ * directory must be exclusive to the cache; the cache may delete or overwrite
+ * files from its directory. It is an error for multiple processes to use the
+ * same cache directory at the same time.
+ *
+ * <p>This cache limits the number of bytes that it will store on the
+ * filesystem. When the number of stored bytes exceeds the limit, the cache will
+ * remove entries in the background until the limit is satisfied. The limit is
+ * not strict: the cache may temporarily exceed it while waiting for files to be
+ * deleted. The limit does not include filesystem overhead or the cache
+ * journal so space-sensitive applications should set a conservative limit.
+ *
+ * <p>Clients call {@link #edit} to create or update the values of an entry. An
+ * entry may have only one editor at one time; if a value is not available to be
+ * edited then {@link #edit} will return null.
+ * <ul>
+ * <li>When an entry is being <strong>created</strong> it is necessary to
+ * supply a full set of values; the empty value should be used as a
+ * placeholder if necessary.
+ * <li>When an entry is being <strong>edited</strong>, it is not necessary
+ * to supply data for every value; values default to their previous
+ * value.
+ * </ul>
+ * Every {@link #edit} call must be matched by a call to {@link Editor#commit}
+ * or {@link Editor#abort}. Committing is atomic: a read observes the full set
+ * of values as they were before or after the commit, but never a mix of values.
+ *
+ * <p>Clients call {@link #get} to read a snapshot of an entry. The read will
+ * observe the value at the time that {@link #get} was called. Updates and
+ * removals after the call do not impact ongoing reads.
+ *
+ * <p>This class is tolerant of some I/O errors. If files are missing from the
+ * filesystem, the corresponding entries will be dropped from the cache. If
+ * an error occurs while writing a cache value, the edit will fail silently.
+ * Callers should handle other problems by catching {@code IOException} and
+ * responding appropriately.
+ */
+public final class DiskLruCache implements Closeable {
+ static final String JOURNAL_FILE = "journal";
+ static final String JOURNAL_FILE_TEMP = "journal.tmp";
+ static final String JOURNAL_FILE_BACKUP = "journal.bkp";
+ static final String MAGIC = "libcore.io.DiskLruCache";
+ static final String VERSION_1 = "1";
+ static final long ANY_SEQUENCE_NUMBER = -1;
+ static final String STRING_KEY_PATTERN = "[a-z0-9_-]{1,120}";
+ static final Pattern LEGAL_KEY_PATTERN = Pattern.compile(STRING_KEY_PATTERN);
+ private static final String CLEAN = "CLEAN";
+ private static final String DIRTY = "DIRTY";
+ private static final String REMOVE = "REMOVE";
+ private static final String READ = "READ";
+
+ /*
+ * This cache uses a journal file named "journal". A typical journal file
+ * looks like this:
+ * libcore.io.DiskLruCache
+ * 1
+ * 100
+ * 2
+ *
+ * CLEAN 3400330d1dfc7f3f7f4b8d4d803dfcf6 832 21054
+ * DIRTY 335c4c6028171cfddfbaae1a9c313c52
+ * CLEAN 335c4c6028171cfddfbaae1a9c313c52 3934 2342
+ * REMOVE 335c4c6028171cfddfbaae1a9c313c52
+ * DIRTY 1ab96a171faeeee38496d8b330771a7a
+ * CLEAN 1ab96a171faeeee38496d8b330771a7a 1600 234
+ * READ 335c4c6028171cfddfbaae1a9c313c52
+ * READ 3400330d1dfc7f3f7f4b8d4d803dfcf6
+ *
+ * The first five lines of the journal form its header. They are the
+ * constant string "libcore.io.DiskLruCache", the disk cache's version,
+ * the application's version, the value count, and a blank line.
+ *
+ * Each of the subsequent lines in the file is a record of the state of a
+ * cache entry. Each line contains space-separated values: a state, a key,
+ * and optional state-specific values.
+ * o DIRTY lines track that an entry is actively being created or updated.
+ * Every successful DIRTY action should be followed by a CLEAN or REMOVE
+ * action. DIRTY lines without a matching CLEAN or REMOVE indicate that
+ * temporary files may need to be deleted.
+ * o CLEAN lines track a cache entry that has been successfully published
+ * and may be read. A publish line is followed by the lengths of each of
+ * its values.
+ * o READ lines track accesses for LRU.
+ * o REMOVE lines track entries that have been deleted.
+ *
+ * The journal file is appended to as cache operations occur. The journal may
+ * occasionally be compacted by dropping redundant lines. A temporary file named
+ * "journal.tmp" will be used during compaction; that file should be deleted if
+ * it exists when the cache is opened.
+ */
+
+ private final File directory;
+ private final File journalFile;
+ private final File journalFileTmp;
+ private final File journalFileBackup;
+ private final int appVersion;
+ private long maxSize;
+ private final int valueCount;
+ private long size = 0;
+ private Writer journalWriter;
+ private final LinkedHashMap<String, Entry> lruEntries =
+ new LinkedHashMap<String, Entry>(0, 0.75f, true);
+ private int redundantOpCount;
+
+ /**
+ * To differentiate between old and current snapshots, each entry is given
+ * a sequence number each time an edit is committed. A snapshot is stale if
+ * its sequence number is not equal to its entry's sequence number.
+ */
+ private long nextSequenceNumber = 0;
+
+ /** This cache uses a single background thread to evict entries. */
+ final ThreadPoolExecutor executorService =
+ new ThreadPoolExecutor(0, 1, 60L, TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>());
+ private final Callable<Void> cleanupCallable = new Callable<Void>() {
+ public Void call() throws Exception {
+ synchronized (DiskLruCache.this) {
+ if (journalWriter == null) {
+ return null; // Closed.
+ }
+ trimToSize();
+ if (journalRebuildRequired()) {
+ rebuildJournal();
+ redundantOpCount = 0;
+ }
+ }
+ return null;
+ }
+ };
+
+ private DiskLruCache(File directory, int appVersion, int valueCount, long maxSize) {
+ this.directory = directory;
+ this.appVersion = appVersion;
+ this.journalFile = new File(directory, JOURNAL_FILE);
+ this.journalFileTmp = new File(directory, JOURNAL_FILE_TEMP);
+ this.journalFileBackup = new File(directory, JOURNAL_FILE_BACKUP);
+ this.valueCount = valueCount;
+ this.maxSize = maxSize;
+ }
+
+ /**
+ * Opens the cache in {@code directory}, creating a cache if none exists
+ * there.
+ *
+ * @param directory a writable directory
+ * @param valueCount the number of values per cache entry. Must be positive.
+ * @param maxSize the maximum number of bytes this cache should use to store
+ * @throws IOException if reading or writing the cache directory fails
+ */
+ public static DiskLruCache open(File directory, int appVersion, int valueCount, long maxSize)
+ throws IOException {
+ if (maxSize <= 0) {
+ throw new IllegalArgumentException("maxSize <= 0");
+ }
+ if (valueCount <= 0) {
+ throw new IllegalArgumentException("valueCount <= 0");
+ }
+
+ // If a bkp file exists, use it instead.
+ File backupFile = new File(directory, JOURNAL_FILE_BACKUP);
+ if (backupFile.exists()) {
+ File journalFile = new File(directory, JOURNAL_FILE);
+ // If journal file also exists just delete backup file.
+ if (journalFile.exists()) {
+ backupFile.delete();
+ } else {
+ renameTo(backupFile, journalFile, false);
+ }
+ }
+
+ // Prefer to pick up where we left off.
+ DiskLruCache cache = new DiskLruCache(directory, appVersion, valueCount, maxSize);
+ if (cache.journalFile.exists()) {
+ try {
+ cache.readJournal();
+ cache.processJournal();
+ return cache;
+ } catch (IOException journalIsCorrupt) {
+ System.out
+ .println("DiskLruCache "
+ + directory
+ + " is corrupt: "
+ + journalIsCorrupt.getMessage()
+ + ", removing");
+ cache.delete();
+ }
+ }
+
+ // Create a new empty cache.
+ directory.mkdirs();
+ cache = new DiskLruCache(directory, appVersion, valueCount, maxSize);
+ cache.rebuildJournal();
+ return cache;
+ }
+
+ private void readJournal() throws IOException {
+ StrictLineReader reader = new StrictLineReader(new FileInputStream(journalFile), Util.US_ASCII);
+ try {
+ String magic = reader.readLine();
+ String version = reader.readLine();
+ String appVersionString = reader.readLine();
+ String valueCountString = reader.readLine();
+ String blank = reader.readLine();
+ if (!MAGIC.equals(magic)
+ || !VERSION_1.equals(version)
+ || !Integer.toString(appVersion).equals(appVersionString)
+ || !Integer.toString(valueCount).equals(valueCountString)
+ || !"".equals(blank)) {
+ throw new IOException("unexpected journal header: [" + magic + ", " + version + ", "
+ + valueCountString + ", " + blank + "]");
+ }
+
+ int lineCount = 0;
+ while (true) {
+ try {
+ readJournalLine(reader.readLine());
+ lineCount++;
+ } catch (EOFException endOfJournal) {
+ break;
+ }
+ }
+ redundantOpCount = lineCount - lruEntries.size();
+
+ // If we ended on a truncated line, rebuild the journal before appending to it.
+ if (reader.hasUnterminatedLine()) {
+ rebuildJournal();
+ } else {
+ journalWriter = new BufferedWriter(new OutputStreamWriter(
+ new FileOutputStream(journalFile, true), Util.US_ASCII));
+ }
+ } finally {
+ Util.closeQuietly(reader);
+ }
+ }
+
+ private void readJournalLine(String line) throws IOException {
+ int firstSpace = line.indexOf(' ');
+ if (firstSpace == -1) {
+ throw new IOException("unexpected journal line: " + line);
+ }
+
+ int keyBegin = firstSpace + 1;
+ int secondSpace = line.indexOf(' ', keyBegin);
+ final String key;
+ if (secondSpace == -1) {
+ key = line.substring(keyBegin);
+ if (firstSpace == REMOVE.length() && line.startsWith(REMOVE)) {
+ lruEntries.remove(key);
+ return;
+ }
+ } else {
+ key = line.substring(keyBegin, secondSpace);
+ }
+
+ Entry entry = lruEntries.get(key);
+ if (entry == null) {
+ entry = new Entry(key);
+ lruEntries.put(key, entry);
+ }
+
+ if (secondSpace != -1 && firstSpace == CLEAN.length() && line.startsWith(CLEAN)) {
+ String[] parts = line.substring(secondSpace + 1).split(" ");
+ entry.readable = true;
+ entry.currentEditor = null;
+ entry.setLengths(parts);
+ } else if (secondSpace == -1 && firstSpace == DIRTY.length() && line.startsWith(DIRTY)) {
+ entry.currentEditor = new Editor(entry);
+ } else if (secondSpace == -1 && firstSpace == READ.length() && line.startsWith(READ)) {
+ // This work was already done by calling lruEntries.get().
+ } else {
+ throw new IOException("unexpected journal line: " + line);
+ }
+ }
+
+ /**
+ * Computes the initial size and collects garbage as a part of opening the
+ * cache. Dirty entries are assumed to be inconsistent and will be deleted.
+ */
+ private void processJournal() throws IOException {
+ deleteIfExists(journalFileTmp);
+ for (Iterator<Entry> i = lruEntries.values().iterator(); i.hasNext(); ) {
+ Entry entry = i.next();
+ if (entry.currentEditor == null) {
+ for (int t = 0; t < valueCount; t++) {
+ size += entry.lengths[t];
+ }
+ } else {
+ entry.currentEditor = null;
+ for (int t = 0; t < valueCount; t++) {
+ deleteIfExists(entry.getCleanFile(t));
+ deleteIfExists(entry.getDirtyFile(t));
+ }
+ i.remove();
+ }
+ }
+ }
+
+ /**
+ * Creates a new journal that omits redundant information. This replaces the
+ * current journal if it exists.
+ */
+ private synchronized void rebuildJournal() throws IOException {
+ if (journalWriter != null) {
+ journalWriter.close();
+ }
+
+ Writer writer = new BufferedWriter(
+ new OutputStreamWriter(new FileOutputStream(journalFileTmp), Util.US_ASCII));
+ try {
+ writer.write(MAGIC);
+ writer.write("\n");
+ writer.write(VERSION_1);
+ writer.write("\n");
+ writer.write(Integer.toString(appVersion));
+ writer.write("\n");
+ writer.write(Integer.toString(valueCount));
+ writer.write("\n");
+ writer.write("\n");
+
+ for (Entry entry : lruEntries.values()) {
+ if (entry.currentEditor != null) {
+ writer.write(DIRTY + ' ' + entry.key + '\n');
+ } else {
+ writer.write(CLEAN + ' ' + entry.key + entry.getLengths() + '\n');
+ }
+ }
+ } finally {
+ writer.close();
+ }
+
+ if (journalFile.exists()) {
+ renameTo(journalFile, journalFileBackup, true);
+ }
+ renameTo(journalFileTmp, journalFile, false);
+ journalFileBackup.delete();
+
+ journalWriter = new BufferedWriter(
+ new OutputStreamWriter(new FileOutputStream(journalFile, true), Util.US_ASCII));
+ }
+
+ private static void deleteIfExists(File file) throws IOException {
+ if (file.exists() && !file.delete()) {
+ throw new IOException();
+ }
+ }
+
+ private static void renameTo(File from, File to, boolean deleteDestination) throws IOException {
+ if (deleteDestination) {
+ deleteIfExists(to);
+ }
+ if (!from.renameTo(to)) {
+ throw new IOException();
+ }
+ }
+
+ /**
+ * Returns a snapshot of the entry named {@code key}, or null if it doesn't
+ * exist is not currently readable. If a value is returned, it is moved to
+ * the head of the LRU queue.
+ */
+ public synchronized Snapshot get(String key) throws IOException {
+ checkNotClosed();
+ validateKey(key);
+ Entry entry = lruEntries.get(key);
+ if (entry == null) {
+ return null;
+ }
+
+ if (!entry.readable) {
+ return null;
+ }
+
+ // Open all streams eagerly to guarantee that we see a single published
+ // snapshot. If we opened streams lazily then the streams could come
+ // from different edits.
+ InputStream[] ins = new InputStream[valueCount];
+ try {
+ for (int i = 0; i < valueCount; i++) {
+ ins[i] = new FileInputStream(entry.getCleanFile(i));
+ }
+ } catch (FileNotFoundException e) {
+ // A file must have been deleted manually!
+ for (int i = 0; i < valueCount; i++) {
+ if (ins[i] != null) {
+ Util.closeQuietly(ins[i]);
+ } else {
+ break;
+ }
+ }
+ return null;
+ }
+
+ redundantOpCount++;
+ journalWriter.append(READ + ' ' + key + '\n');
+ if (journalRebuildRequired()) {
+ executorService.submit(cleanupCallable);
+ }
+
+ return new Snapshot(key, entry.sequenceNumber, ins, entry.lengths);
+ }
+
+ /**
+ * Returns an editor for the entry named {@code key}, or null if another
+ * edit is in progress.
+ */
+ public Editor edit(String key) throws IOException {
+ return edit(key, ANY_SEQUENCE_NUMBER);
+ }
+
+ private synchronized Editor edit(String key, long expectedSequenceNumber) throws IOException {
+ checkNotClosed();
+ validateKey(key);
+ Entry entry = lruEntries.get(key);
+ if (expectedSequenceNumber != ANY_SEQUENCE_NUMBER && (entry == null
+ || entry.sequenceNumber != expectedSequenceNumber)) {
+ return null; // Snapshot is stale.
+ }
+ if (entry == null) {
+ entry = new Entry(key);
+ lruEntries.put(key, entry);
+ } else if (entry.currentEditor != null) {
+ return null; // Another edit is in progress.
+ }
+
+ Editor editor = new Editor(entry);
+ entry.currentEditor = editor;
+
+ // Flush the journal before creating files to prevent file leaks.
+ journalWriter.write(DIRTY + ' ' + key + '\n');
+ journalWriter.flush();
+ return editor;
+ }
+
+ /** Returns the directory where this cache stores its data. */
+ public File getDirectory() {
+ return directory;
+ }
+
+ /**
+ * Returns the maximum number of bytes that this cache should use to store
+ * its data.
+ */
+ public synchronized long getMaxSize() {
+ return maxSize;
+ }
+
+ /**
+ * Changes the maximum number of bytes the cache can store and queues a job
+ * to trim the existing store, if necessary.
+ */
+ public synchronized void setMaxSize(long maxSize) {
+ this.maxSize = maxSize;
+ executorService.submit(cleanupCallable);
+ }
+
+ /**
+ * Returns the number of bytes currently being used to store the values in
+ * this cache. This may be greater than the max size if a background
+ * deletion is pending.
+ */
+ public synchronized long size() {
+ return size;
+ }
+
+ private synchronized void completeEdit(Editor editor, boolean success) throws IOException {
+ Entry entry = editor.entry;
+ if (entry.currentEditor != editor) {
+ throw new IllegalStateException();
+ }
+
+ // If this edit is creating the entry for the first time, every index must have a value.
+ if (success && !entry.readable) {
+ for (int i = 0; i < valueCount; i++) {
+ if (!editor.written[i]) {
+ editor.abort();
+ throw new IllegalStateException("Newly created entry didn't create value for index " + i);
+ }
+ if (!entry.getDirtyFile(i).exists()) {
+ editor.abort();
+ return;
+ }
+ }
+ }
+
+ for (int i = 0; i < valueCount; i++) {
+ File dirty = entry.getDirtyFile(i);
+ if (success) {
+ if (dirty.exists()) {
+ File clean = entry.getCleanFile(i);
+ dirty.renameTo(clean);
+ long oldLength = entry.lengths[i];
+ long newLength = clean.length();
+ entry.lengths[i] = newLength;
+ size = size - oldLength + newLength;
+ }
+ } else {
+ deleteIfExists(dirty);
+ }
+ }
+
+ redundantOpCount++;
+ entry.currentEditor = null;
+ if (entry.readable | success) {
+ entry.readable = true;
+ journalWriter.write(CLEAN + ' ' + entry.key + entry.getLengths() + '\n');
+ if (success) {
+ entry.sequenceNumber = nextSequenceNumber++;
+ }
+ } else {
+ lruEntries.remove(entry.key);
+ journalWriter.write(REMOVE + ' ' + entry.key + '\n');
+ }
+ journalWriter.flush();
+
+ if (size > maxSize || journalRebuildRequired()) {
+ executorService.submit(cleanupCallable);
+ }
+ }
+
+ /**
+ * We only rebuild the journal when it will halve the size of the journal
+ * and eliminate at least 2000 ops.
+ */
+ private boolean journalRebuildRequired() {
+ final int redundantOpCompactThreshold = 2000;
+ return redundantOpCount >= redundantOpCompactThreshold //
+ && redundantOpCount >= lruEntries.size();
+ }
+
+ /**
+ * Drops the entry for {@code key} if it exists and can be removed. Entries
+ * actively being edited cannot be removed.
+ *
+ * @return true if an entry was removed.
+ */
+ public synchronized boolean remove(String key) throws IOException {
+ checkNotClosed();
+ validateKey(key);
+ Entry entry = lruEntries.get(key);
+ if (entry == null || entry.currentEditor != null) {
+ return false;
+ }
+
+ for (int i = 0; i < valueCount; i++) {
+ File file = entry.getCleanFile(i);
+ if (file.exists() && !file.delete()) {
+ throw new IOException("failed to delete " + file);
+ }
+ size -= entry.lengths[i];
+ entry.lengths[i] = 0;
+ }
+
+ redundantOpCount++;
+ journalWriter.append(REMOVE + ' ' + key + '\n');
+ lruEntries.remove(key);
+
+ if (journalRebuildRequired()) {
+ executorService.submit(cleanupCallable);
+ }
+
+ return true;
+ }
+
+ /** Returns true if this cache has been closed. */
+ public synchronized boolean isClosed() {
+ return journalWriter == null;
+ }
+
+ private void checkNotClosed() {
+ if (journalWriter == null) {
+ throw new IllegalStateException("cache is closed");
+ }
+ }
+
+ /** Force buffered operations to the filesystem. */
+ public synchronized void flush() throws IOException {
+ checkNotClosed();
+ trimToSize();
+ journalWriter.flush();
+ }
+
+ /** Closes this cache. Stored values will remain on the filesystem. */
+ public synchronized void close() throws IOException {
+ if (journalWriter == null) {
+ return; // Already closed.
+ }
+ for (Entry entry : new ArrayList<Entry>(lruEntries.values())) {
+ if (entry.currentEditor != null) {
+ entry.currentEditor.abort();
+ }
+ }
+ trimToSize();
+ journalWriter.close();
+ journalWriter = null;
+ }
+
+ private void trimToSize() throws IOException {
+ while (size > maxSize) {
+ Map.Entry<String, Entry> toEvict = lruEntries.entrySet().iterator().next();
+ remove(toEvict.getKey());
+ }
+ }
+
+ /**
+ * Closes the cache and deletes all of its stored values. This will delete
+ * all files in the cache directory including files that weren't created by
+ * the cache.
+ */
+ public void delete() throws IOException {
+ close();
+ Util.deleteContents(directory);
+ }
+
+ private void validateKey(String key) {
+ Matcher matcher = LEGAL_KEY_PATTERN.matcher(key);
+ if (!matcher.matches()) {
+ throw new IllegalArgumentException("keys must match regex "
+ + STRING_KEY_PATTERN + ": \"" + key + "\"");
+ }
+ }
+
+ private static String inputStreamToString(InputStream in) throws IOException {
+ return Util.readFully(new InputStreamReader(in, Util.UTF_8));
+ }
+
+ /** A snapshot of the values for an entry. */
+ public final class Snapshot implements Closeable {
+ private final String key;
+ private final long sequenceNumber;
+ private final InputStream[] ins;
+ private final long[] lengths;
+
+ private Snapshot(String key, long sequenceNumber, InputStream[] ins, long[] lengths) {
+ this.key = key;
+ this.sequenceNumber = sequenceNumber;
+ this.ins = ins;
+ this.lengths = lengths;
+ }
+
+ /**
+ * Returns an editor for this snapshot's entry, or null if either the
+ * entry has changed since this snapshot was created or if another edit
+ * is in progress.
+ */
+ public Editor edit() throws IOException {
+ return DiskLruCache.this.edit(key, sequenceNumber);
+ }
+
+ /** Returns the unbuffered stream with the value for {@code index}. */
+ public InputStream getInputStream(int index) {
+ return ins[index];
+ }
+
+ /** Returns the string value for {@code index}. */
+ public String getString(int index) throws IOException {
+ return inputStreamToString(getInputStream(index));
+ }
+
+ /** Returns the byte length of the value for {@code index}. */
+ public long getLength(int index) {
+ return lengths[index];
+ }
+
+ public void close() {
+ for (InputStream in : ins) {
+ Util.closeQuietly(in);
+ }
+ }
+ }
+
+ private static final OutputStream NULL_OUTPUT_STREAM = new OutputStream() {
+ @Override
+ public void write(int b) throws IOException {
+ // Eat all writes silently. Nom nom.
+ }
+ };
+
+ /** Edits the values for an entry. */
+ public final class Editor {
+ private final Entry entry;
+ private final boolean[] written;
+ private boolean hasErrors;
+ private boolean committed;
+
+ private Editor(Entry entry) {
+ this.entry = entry;
+ this.written = (entry.readable) ? null : new boolean[valueCount];
+ }
+
+ /**
+ * Returns an unbuffered input stream to read the last committed value,
+ * or null if no value has been committed.
+ */
+ public InputStream newInputStream(int index) throws IOException {
+ synchronized (DiskLruCache.this) {
+ if (entry.currentEditor != this) {
+ throw new IllegalStateException();
+ }
+ if (!entry.readable) {
+ return null;
+ }
+ try {
+ return new FileInputStream(entry.getCleanFile(index));
+ } catch (FileNotFoundException e) {
+ return null;
+ }
+ }
+ }
+
+ /**
+ * Returns the last committed value as a string, or null if no value
+ * has been committed.
+ */
+ public String getString(int index) throws IOException {
+ InputStream in = newInputStream(index);
+ return in != null ? inputStreamToString(in) : null;
+ }
+
+ /**
+ * Returns a new unbuffered output stream to write the value at
+ * {@code index}. If the underlying output stream encounters errors
+ * when writing to the filesystem, this edit will be aborted when
+ * {@link #commit} is called. The returned output stream does not throw
+ * IOExceptions.
+ */
+ public OutputStream newOutputStream(int index) throws IOException {
+ if (index < 0 || index >= valueCount) {
+ throw new IllegalArgumentException("Expected index " + index + " to "
+ + "be greater than 0 and less than the maximum value count "
+ + "of " + valueCount);
+ }
+ synchronized (DiskLruCache.this) {
+ if (entry.currentEditor != this) {
+ throw new IllegalStateException();
+ }
+ if (!entry.readable) {
+ written[index] = true;
+ }
+ File dirtyFile = entry.getDirtyFile(index);
+ FileOutputStream outputStream;
+ try {
+ outputStream = new FileOutputStream(dirtyFile);
+ } catch (FileNotFoundException e) {
+ // Attempt to recreate the cache directory.
+ directory.mkdirs();
+ try {
+ outputStream = new FileOutputStream(dirtyFile);
+ } catch (FileNotFoundException e2) {
+ // We are unable to recover. Silently eat the writes.
+ return NULL_OUTPUT_STREAM;
+ }
+ }
+ return new FaultHidingOutputStream(outputStream);
+ }
+ }
+
+ /** Sets the value at {@code index} to {@code value}. */
+ public void set(int index, String value) throws IOException {
+ Writer writer = null;
+ try {
+ writer = new OutputStreamWriter(newOutputStream(index), Util.UTF_8);
+ writer.write(value);
+ } finally {
+ Util.closeQuietly(writer);
+ }
+ }
+
+ /**
+ * Commits this edit so it is visible to readers. This releases the
+ * edit lock so another edit may be started on the same key.
+ */
+ public void commit() throws IOException {
+ if (hasErrors) {
+ completeEdit(this, false);
+ remove(entry.key); // The previous entry is stale.
+ } else {
+ completeEdit(this, true);
+ }
+ committed = true;
+ }
+
+ /**
+ * Aborts this edit. This releases the edit lock so another edit may be
+ * started on the same key.
+ */
+ public void abort() throws IOException {
+ completeEdit(this, false);
+ }
+
+ public void abortUnlessCommitted() {
+ if (!committed) {
+ try {
+ abort();
+ } catch (IOException ignored) {
+ }
+ }
+ }
+
+ private class FaultHidingOutputStream extends FilterOutputStream {
+ private FaultHidingOutputStream(OutputStream out) {
+ super(out);
+ }
+
+ @Override public void write(int oneByte) {
+ try {
+ out.write(oneByte);
+ } catch (IOException e) {
+ hasErrors = true;
+ }
+ }
+
+ @Override public void write(byte[] buffer, int offset, int length) {
+ try {
+ out.write(buffer, offset, length);
+ } catch (IOException e) {
+ hasErrors = true;
+ }
+ }
+
+ @Override public void close() {
+ try {
+ out.close();
+ } catch (IOException e) {
+ hasErrors = true;
+ }
+ }
+
+ @Override public void flush() {
+ try {
+ out.flush();
+ } catch (IOException e) {
+ hasErrors = true;
+ }
+ }
+ }
+ }
+
+ private final class Entry {
+ private final String key;
+
+ /** Lengths of this entry's files. */
+ private final long[] lengths;
+
+ /** True if this entry has ever been published. */
+ private boolean readable;
+
+ /** The ongoing edit or null if this entry is not being edited. */
+ private Editor currentEditor;
+
+ /** The sequence number of the most recently committed edit to this entry. */
+ private long sequenceNumber;
+
+ private Entry(String key) {
+ this.key = key;
+ this.lengths = new long[valueCount];
+ }
+
+ public String getLengths() {
+ StringBuilder result = new StringBuilder();
+ for (long size : lengths) {
+ result.append(' ').append(size);
+ }
+ return result.toString();
+ }
+
+ /** Set lengths using decimal numbers like "10123". */
+ private void setLengths(String[] strings) throws IOException {
+ if (strings.length != valueCount) {
+ throw invalidLengths(strings);
+ }
+
+ try {
+ for (int i = 0; i < strings.length; i++) {
+ lengths[i] = Long.parseLong(strings[i]);
+ }
+ } catch (NumberFormatException e) {
+ throw invalidLengths(strings);
+ }
+ }
+
+ private IOException invalidLengths(String[] strings) throws IOException {
+ throw new IOException("unexpected journal line: " + java.util.Arrays.toString(strings));
+ }
+
+ public File getCleanFile(int i) {
+ return new File(directory, key + "." + i);
+ }
+
+ public File getDirtyFile(int i) {
+ return new File(directory, key + "." + i + ".tmp");
+ }
+ }
+}
--- /dev/null
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed 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.lineageos.eleven.cache.disklrucache;
+
+import java.io.ByteArrayOutputStream;
+import java.io.Closeable;
+import java.io.EOFException;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.UnsupportedEncodingException;
+import java.nio.charset.Charset;
+
+/**
+ * Buffers input from an {@link InputStream} for reading lines.
+ *
+ * <p>This class is used for buffered reading of lines. For purposes of this class, a line ends
+ * with "\n" or "\r\n". End of input is reported by throwing {@code EOFException}. Unterminated
+ * line at end of input is invalid and will be ignored, the caller may use {@code
+ * hasUnterminatedLine()} to detect it after catching the {@code EOFException}.
+ *
+ * <p>This class is intended for reading input that strictly consists of lines, such as line-based
+ * cache entries or cache journal. Unlike the {@link java.io.BufferedReader} which in conjunction
+ * with {@link java.io.InputStreamReader} provides similar functionality, this class uses different
+ * end-of-input reporting and a more restrictive definition of a line.
+ *
+ * <p>This class supports only charsets that encode '\r' and '\n' as a single byte with value 13
+ * and 10, respectively, and the representation of no other character contains these values.
+ * We currently check in constructor that the charset is one of US-ASCII, UTF-8 and ISO-8859-1.
+ * The default charset is US_ASCII.
+ */
+class StrictLineReader implements Closeable {
+ private static final byte CR = (byte) '\r';
+ private static final byte LF = (byte) '\n';
+
+ private final InputStream in;
+ private final Charset charset;
+
+ /*
+ * Buffered data is stored in {@code buf}. As long as no exception occurs, 0 <= pos <= end
+ * and the data in the range [pos, end) is buffered for reading. At end of input, if there is
+ * an unterminated line, we set end == -1, otherwise end == pos. If the underlying
+ * {@code InputStream} throws an {@code IOException}, end may remain as either pos or -1.
+ */
+ private byte[] buf;
+ private int pos;
+ private int end;
+
+ /**
+ * Constructs a new {@code LineReader} with the specified charset and the default capacity.
+ *
+ * @param in the {@code InputStream} to read data from.
+ * @param charset the charset used to decode data. Only US-ASCII, UTF-8 and ISO-8859-1 are
+ * supported.
+ * @throws NullPointerException if {@code in} or {@code charset} is null.
+ * @throws IllegalArgumentException if the specified charset is not supported.
+ */
+ public StrictLineReader(InputStream in, Charset charset) {
+ this(in, 8192, charset);
+ }
+
+ /**
+ * Constructs a new {@code LineReader} with the specified capacity and charset.
+ *
+ * @param in the {@code InputStream} to read data from.
+ * @param capacity the capacity of the buffer.
+ * @param charset the charset used to decode data. Only US-ASCII, UTF-8 and ISO-8859-1 are
+ * supported.
+ * @throws NullPointerException if {@code in} or {@code charset} is null.
+ * @throws IllegalArgumentException if {@code capacity} is negative or zero
+ * or the specified charset is not supported.
+ */
+ public StrictLineReader(InputStream in, int capacity, Charset charset) {
+ if (in == null || charset == null) {
+ throw new NullPointerException();
+ }
+ if (capacity < 0) {
+ throw new IllegalArgumentException("capacity <= 0");
+ }
+ if (!(charset.equals(Util.US_ASCII))) {
+ throw new IllegalArgumentException("Unsupported encoding");
+ }
+
+ this.in = in;
+ this.charset = charset;
+ buf = new byte[capacity];
+ }
+
+ /**
+ * Closes the reader by closing the underlying {@code InputStream} and
+ * marking this reader as closed.
+ *
+ * @throws IOException for errors when closing the underlying {@code InputStream}.
+ */
+ public void close() throws IOException {
+ synchronized (in) {
+ if (buf != null) {
+ buf = null;
+ in.close();
+ }
+ }
+ }
+
+ /**
+ * Reads the next line. A line ends with {@code "\n"} or {@code "\r\n"},
+ * this end of line marker is not included in the result.
+ *
+ * @return the next line from the input.
+ * @throws IOException for underlying {@code InputStream} errors.
+ * @throws EOFException for the end of source stream.
+ */
+ public String readLine() throws IOException {
+ synchronized (in) {
+ if (buf == null) {
+ throw new IOException("LineReader is closed");
+ }
+
+ // Read more data if we are at the end of the buffered data.
+ // Though it's an error to read after an exception, we will let {@code fillBuf()}
+ // throw again if that happens; thus we need to handle end == -1 as well as end == pos.
+ if (pos >= end) {
+ fillBuf();
+ }
+ // Try to find LF in the buffered data and return the line if successful.
+ for (int i = pos; i != end; ++i) {
+ if (buf[i] == LF) {
+ int lineEnd = (i != pos && buf[i - 1] == CR) ? i - 1 : i;
+ String res = new String(buf, pos, lineEnd - pos, charset.name());
+ pos = i + 1;
+ return res;
+ }
+ }
+
+ // Let's anticipate up to 80 characters on top of those already read.
+ ByteArrayOutputStream out = new ByteArrayOutputStream(end - pos + 80) {
+ @Override
+ public String toString() {
+ int length = (count > 0 && buf[count - 1] == CR) ? count - 1 : count;
+ try {
+ return new String(buf, 0, length, charset.name());
+ } catch (UnsupportedEncodingException e) {
+ throw new AssertionError(e); // Since we control the charset this will never happen.
+ }
+ }
+ };
+
+ while (true) {
+ out.write(buf, pos, end - pos);
+ // Mark unterminated line in case fillBuf throws EOFException or IOException.
+ end = -1;
+ fillBuf();
+ // Try to find LF in the buffered data and return the line if successful.
+ for (int i = pos; i != end; ++i) {
+ if (buf[i] == LF) {
+ if (i != pos) {
+ out.write(buf, pos, i - pos);
+ }
+ pos = i + 1;
+ return out.toString();
+ }
+ }
+ }
+ }
+ }
+
+ public boolean hasUnterminatedLine() {
+ return end == -1;
+ }
+
+ /**
+ * Reads new input data into the buffer. Call only with pos == end or end == -1,
+ * depending on the desired outcome if the function throws.
+ */
+ private void fillBuf() throws IOException {
+ int result = in.read(buf, 0, buf.length);
+ if (result == -1) {
+ throw new EOFException();
+ }
+ pos = 0;
+ end = result;
+ }
+}
+
--- /dev/null
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed 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.lineageos.eleven.cache.disklrucache;
+
+import java.io.Closeable;
+import java.io.File;
+import java.io.IOException;
+import java.io.Reader;
+import java.io.StringWriter;
+import java.nio.charset.Charset;
+
+/** Junk drawer of utility methods. */
+final class Util {
+ static final Charset US_ASCII = Charset.forName("US-ASCII");
+ static final Charset UTF_8 = Charset.forName("UTF-8");
+
+ private Util() {
+ }
+
+ static String readFully(Reader reader) throws IOException {
+ try {
+ StringWriter writer = new StringWriter();
+ char[] buffer = new char[1024];
+ int count;
+ while ((count = reader.read(buffer)) != -1) {
+ writer.write(buffer, 0, count);
+ }
+ return writer.toString();
+ } finally {
+ reader.close();
+ }
+ }
+
+ /**
+ * Deletes the contents of {@code dir}. Throws an IOException if any file
+ * could not be deleted, or if {@code dir} is not a readable directory.
+ */
+ static void deleteContents(File dir) throws IOException {
+ File[] files = dir.listFiles();
+ if (files == null) {
+ throw new IOException("not a readable directory: " + dir);
+ }
+ for (File file : files) {
+ if (file.isDirectory()) {
+ deleteContents(file);
+ }
+ if (!file.delete()) {
+ throw new IOException("failed to delete file: " + file);
+ }
+ }
+ }
+
+ static void closeQuietly(/*Auto*/Closeable closeable) {
+ if (closeable != null) {
+ try {
+ closeable.close();
+ } catch (RuntimeException rethrown) {
+ throw rethrown;
+ } catch (Exception ignored) {
+ }
+ }
+ }
+}
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