// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
package org.chromium.chrome.browser.suggestions.mostvisited;
import android.content.Context;
import androidx.annotation.VisibleForTesting;
import androidx.core.util.AtomicFile;
import org.chromium.base.ContextUtils;
import org.chromium.base.Log;
import org.chromium.base.ResettersForTesting;
import org.chromium.base.StreamUtil;
import org.chromium.base.task.AsyncTask;
import org.chromium.chrome.browser.suggestions.SiteSuggestion;
import org.chromium.chrome.browser.suggestions.tile.Tile;
import org.chromium.url.GURL;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
/** This class provides methods to write/read most visited sites related info to devices. */
public class MostVisitedSitesMetadataUtils {
private static final String TAG = "TopSites";
/** The singleton helper class for this class. */
private static class SingletonHelper {
private static final MostVisitedSitesMetadataUtils INSTANCE =
new MostVisitedSitesMetadataUtils();
}
/** Prevents two state directories from getting created simultaneously. */
private static final Object DIR_CREATION_LOCK = new Object();
/** Prevents two MostVisitedSitesUtils from saving the same file simultaneously. */
private static final Object SAVE_LIST_LOCK = new Object();
/** Current version of the cache, to be updated when the cache structure or meaning changes. */
private static final int CACHE_VERSION = 1;
private static File sStateDirectory;
private static String sStateDirName = "top_sites";
private static String sStateFileName = "top_sites";
private Runnable mCurrentTask;
private Runnable mPendingTask;
private int mPendingTaskTilesNumForTesting;
/**
* @return The singleton instance.
*/
public static MostVisitedSitesMetadataUtils getInstance() {
return SingletonHelper.INSTANCE;
}
/**
* Save new suggestion tiles to the disk. If there is already a task running, save this new
* saving task as |mPendingTask|.
* @param suggestionTiles The site suggestion tiles.
*/
public void saveSuggestionListsToFile(List<Tile> suggestionTiles) {
Runnable newTask =
() -> saveSuggestionListsToFile(suggestionTiles, this::updatePendingToCurrent);
if (mCurrentTask != null) {
// Skip last mPendingTask which is not necessary to run.
mPendingTask = newTask;
mPendingTaskTilesNumForTesting = suggestionTiles.size();
} else {
// Assign newTask to mCurrentTask and run this task.
mCurrentTask = newTask;
// Skip any pending task.
mPendingTask = null;
Log.i(TAG, "Start a new task.");
mCurrentTask.run();
}
}
/**
* Restore the suggestion lists from the disk and deserialize them.
* @return Suggestion lists
* IOException: If there is any problem when restoring file or deserialize data, remove the
* stale files and throw an exception, then the UI thread will know there is no cache file and
* show something else.
*/
public static List<Tile> restoreFileToSuggestionLists() throws IOException {
List<Tile> tiles;
try {
byte[] listData = restoreFileToBytes(getOrCreateTopSitesDirectory(), sStateFileName);
tiles = deserializeTopSitesData(listData);
} catch (IOException e) {
getOrCreateTopSitesDirectory().delete();
throw e;
}
return tiles;
}
/**
* Restore the suggestion lists from the disk and deserialize them on UI thread.
*
* @return Suggestion lists IOException: If there is any problem when restoring file or
* deserialize data, remove the stale files and throw an exception, then the UI thread will
* know there is no cache file and show something else.
*/
public static List<Tile> restoreFileToSuggestionListsOnUiThread() throws IOException {
return restoreFileToSuggestionLists();
}
/**
* Asynchronously serialize the suggestion lists and save it into the disk.
*
* @param suggestionTiles The site suggestion tiles.
* @param callback Callback function after saving file.
*/
@VisibleForTesting(otherwise = VisibleForTesting.PRIVATE)
public static void saveSuggestionListsToFile(List<Tile> suggestionTiles, Runnable callback) {
new AsyncTask<Void>() {
@Override
protected Void doInBackground() {
try {
byte[] listData = serializeTopSitesData(suggestionTiles);
saveSuggestionListsToFile(
getOrCreateTopSitesDirectory(), sStateFileName, listData);
} catch (IOException e) {
Log.e(TAG, "Fail to save file.");
}
return null;
}
@Override
protected void onPostExecute(Void aVoid) {
if (callback != null) {
callback.run();
}
}
}.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
}
private static byte[] serializeTopSitesData(List<Tile> suggestionTiles) throws IOException {
int topSitesCount = suggestionTiles.size();
ByteArrayOutputStream output = new ByteArrayOutputStream();
DataOutputStream stream = new DataOutputStream(output);
// Save the count of the list of top sites to restore.
stream.writeInt(topSitesCount);
// Save top sites.
for (int i = 0; i < topSitesCount; i++) {
stream.writeInt(CACHE_VERSION);
stream.writeInt(suggestionTiles.get(i).getIndex());
SiteSuggestion suggestionInfo = suggestionTiles.get(i).getData();
stream.writeUTF(suggestionInfo.title);
stream.writeUTF(suggestionInfo.url.serialize());
// Write an empty string for the allowlistIconPath, which is a deprecated field.
stream.writeUTF("");
stream.writeInt(suggestionInfo.titleSource);
stream.writeInt(suggestionInfo.source);
stream.writeInt(suggestionInfo.sectionType);
}
stream.close();
Log.i(TAG, "Serializing top sites lists finished; count: " + topSitesCount);
return output.toByteArray();
}
private static List<Tile> deserializeTopSitesData(byte[] listData) throws IOException {
if (listData == null || listData.length == 0) {
return null;
}
DataInputStream stream = new DataInputStream(new ByteArrayInputStream(listData));
// Get how many top sites there are.
final int count = stream.readInt();
// Restore top sites.
List<Tile> tiles = new ArrayList<>();
for (int i = 0; i < count; i++) {
int version = stream.readInt();
if (version > CACHE_VERSION) {
throw new IOException("Cache version not supported.");
}
int index = stream.readInt();
String title = stream.readUTF();
GURL url = GURL.deserialize(stream.readUTF());
if (url.isEmpty()) throw new IOException("GURL deserialization failed.");
// Read the allowlistIconPath, which is always an empty string.
String allowlistIconPath = stream.readUTF();
int titleSource = stream.readInt();
int source = stream.readInt();
int sectionType = stream.readInt();
SiteSuggestion newSite =
new SiteSuggestion(title, url, titleSource, source, sectionType);
Tile newTile = new Tile(newSite, index);
tiles.add(newTile);
}
Log.i(TAG, "Deserializing top sites lists finished");
return tiles;
}
/**
* Atomically writes the given serialized data out to disk.
* @param stateDirectory Directory to save top sites data into.
* @param stateFileName File name to save top sites data into.
* @param listData Top sites data in the form of a serialized byte array.
*/
private static void saveSuggestionListsToFile(
File stateDirectory, String stateFileName, byte[] listData) {
synchronized (SAVE_LIST_LOCK) {
File metadataFile = new File(stateDirectory, stateFileName);
AtomicFile file = new AtomicFile(metadataFile);
FileOutputStream stream = null;
try {
stream = file.startWrite();
stream.write(listData, 0, listData.length);
file.finishWrite(stream);
Log.i(
TAG,
"Finished saving top sites list to file:" + metadataFile.getAbsolutePath());
} catch (IOException e) {
if (stream != null) file.failWrite(stream);
Log.e(TAG, "Fail to write file: " + metadataFile.getAbsolutePath());
}
}
}
/**
* Restore serialized data from disk.
* @param stateDirectory Directory to save top sites data into.
* @param stateFileName File name to save top sites data into.
* @return Top sites data in the form of a serialized byte array.
*/
private static byte[] restoreFileToBytes(File stateDirectory, String stateFileName)
throws IOException {
FileInputStream stream;
byte[] data;
File stateFile = new File(stateDirectory, stateFileName);
stream = new FileInputStream(stateFile);
data = new byte[(int) stateFile.length()];
stream.read(data);
Log.i(TAG, "Finished fetching top sites list.");
StreamUtil.closeQuietly(stream);
return data;
}
@VisibleForTesting(otherwise = VisibleForTesting.PRIVATE)
public static File getOrCreateTopSitesDirectory() {
synchronized (DIR_CREATION_LOCK) {
if (sStateDirectory == null) {
sStateDirectory =
ContextUtils.getApplicationContext()
.getDir(sStateDirName, Context.MODE_PRIVATE);
}
}
return sStateDirectory;
}
private void updatePendingToCurrent() {
mCurrentTask = mPendingTask;
mPendingTask = null;
if (mCurrentTask != null) {
Log.i(TAG, "Start a new task.");
mCurrentTask.run();
}
}
public Runnable getCurrentTaskForTesting() {
return mCurrentTask;
}
public void setCurrentTaskForTesting(Runnable currentTask) {
var oldValue = mCurrentTask;
mCurrentTask = currentTask;
ResettersForTesting.register(() -> mCurrentTask = oldValue);
}
public void setPendingTaskForTesting(Runnable pendingTask) {
var oldValue = mPendingTask;
mPendingTask = pendingTask;
ResettersForTesting.register(() -> mPendingTask = oldValue);
}
public int getPendingTaskTilesNumForTesting() {
return mPendingTaskTilesNumForTesting;
}
}
Codebase Browser
chromium