Upstream WebappDirectoryManager

chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDirectoryManager.java

Index: chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDirectoryManager.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDirectoryManager.java b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDirectoryManager.java
new file mode 100644
index 0000000000000000000000000000000000000000..d60dd9efca515fe8b696db3541bef3faccc87207
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappDirectoryManager.java
@@ -0,0 +1,167 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// 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.webapps;
+
+import android.annotation.TargetApi;
+import android.app.ActivityManager;
+import android.app.ActivityManager.AppTask;
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.Intent;
+import android.net.Uri;
+import android.os.AsyncTask;
+import android.os.Build;
+import android.text.TextUtils;
+import android.util.Log;
+
+import org.chromium.base.ApplicationStatus;
+import org.chromium.chrome.browser.document.DocumentUtils;
+
+import java.io.File;
+import java.util.HashSet;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+/**
+ * Manages directories created to store data for webapps.
+ *
+ * Directories managed by this class are all subdirectories of the app_WebappActivity/ directory,
+ * which each WebappActivity using a directory named either for its Webapp's ID in Document mode,
+ * or the index of the WebappActivity if it is a subclass of the WebappManagedActivity class (which
+ * are used in pre-L devices to allow multiple WebappActivities launching).
+ */
+public class WebappDirectoryManager extends AsyncTask<Void, Void, Void> {
+    private static final String TAG = "WebappDirectoryCleaner";
+    private static final String WEBAPP_DIRECTORY_NAME = "WebappActivity";
+
+    /** Whether or not the class has already started trying to clean up obsolete directories. */
+    private static final AtomicBoolean sMustCleanUpOldDirectories = new AtomicBoolean(true);
+
+    /** Scheme used for Intents fired for WebappActivity instances. */
+    private final String mWebappScheme;
+
+    /** Directories that will be deleted. */
+    private final HashSet<File> mDirectoriesToDelete;
+
+    /**
+     * Constructs a WebappDirectoryManager, which will manage the deletion of directories
+     * corresponding to webapps that no longer need their data.
+     *
+     * Should be called by WebappActivities after they have restored all the data they need from
+     * their directory.
+     *
+     * @param directory Directory that must be deleted.  Corresponds to the current webapp.
+     * @param webappScheme Scheme used for WebappActivities when building their Intent data URIs.
+     * @param deleteOldDirectories Whether directories for old WebappActivities should be purged.
+     */
+    public WebappDirectoryManager(
+            final File directory, String webappScheme, boolean deleteOldDirectories) {
+        mWebappScheme = webappScheme;
+
+        mDirectoriesToDelete = new HashSet<File>();
+        mDirectoriesToDelete.add(directory);
+
+        if (deleteOldDirectories && sMustCleanUpOldDirectories.getAndSet(false)) {
+            assert Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP;
+            Context context = ApplicationStatus.getApplicationContext();
+            cleanUpOldWebappDirectories(
+                    mDirectoriesToDelete, context.getApplicationInfo().dataDir);
+        }
+    }
+
+    @Override
+    protected Void doInBackground(Void... params) {
+        for (File directory : mDirectoriesToDelete) {
+            if (isCancelled()) return null;
+
+            // Delete all the files in the directory.
+            for (File file : directory.listFiles()) {
+                if (!file.delete()) Log.e(TAG, "Failed to delete file: " + file.getPath());
+            }
+
+            // Delete the directory itself.
+            if (!directory.delete()) {
+                Log.e(TAG, "Failed to delete directory: " + directory.getPath());
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Removes all directories using the old pre-K directory structure, which used directories named
+     * app_WebappActivity*.  Also deletes directories corresponding to WebappActivities that are no
+     * longer listed in Android's recents, since these will be unable to restore their data, anyway.
+     * @param directoriesToDelete Set to append directory names to.
+     * @param baseDirectory Base directory of all of Chrome's persisted files.
+     */
+    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
+    private void cleanUpOldWebappDirectories(
+            HashSet<File> directoriesToDelete, String baseDirectory) {
+        Context context = ApplicationStatus.getApplicationContext();
+
+        String webappDirectoryAppBaseName =
+                context.getDir(WEBAPP_DIRECTORY_NAME, Context.MODE_PRIVATE).getName();
+
+        // Figure out what WebappActivities are still listed in Android's recents menu.
+        HashSet<String> liveWebapps = new HashSet<String>();
+        ActivityManager manager =
+                (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
+        for (AppTask task : manager.getAppTasks()) {
+            Intent intent = DocumentUtils.getBaseIntentFromTask(task);
+            if (intent == null) continue;
+
+            Uri data = intent.getData();
+            if (data != null && TextUtils.equals(mWebappScheme, data.getScheme())) {
+                liveWebapps.add(data.getHost());
+            }
+
+            // WebappManagedActivities have titles from "WebappActivity0" through "WebappActivity9".
+            ComponentName component = intent.getComponent();
+            if (component != null) {
+                String fullClassName = component.getClassName();
+                int lastPeriodIndex = fullClassName.lastIndexOf(".");
+                if (lastPeriodIndex != -1) {
+                    String className = fullClassName.substring(lastPeriodIndex + 1);
+                    if (className.startsWith(WEBAPP_DIRECTORY_NAME)
+                            && className.length() > WEBAPP_DIRECTORY_NAME.length()) {
+                        String activityIndex = className.substring(WEBAPP_DIRECTORY_NAME.length());
+                        liveWebapps.add(activityIndex);
+                    }
+                }
+            }
+        }
+
+        // Delete all webapp directories in the main directory.
+        File dataDirectory = new File(baseDirectory);
+        for (File file : dataDirectory.listFiles()) {
+            String filename = file.getName();
+            if (!filename.startsWith(webappDirectoryAppBaseName)) continue;
+            if (filename.length() == webappDirectoryAppBaseName.length()) continue;
+            directoriesToDelete.add(file);
+        }
+
+        // Clean out webapp directories no longer corresponding to tasks in Recents.
+        File webappBaseDirectory = context.getDir(WEBAPP_DIRECTORY_NAME, Context.MODE_PRIVATE);
+        if (webappBaseDirectory.exists()) {
+            for (File file : webappBaseDirectory.listFiles()) {
+                if (!liveWebapps.contains(file.getName())) directoriesToDelete.add(file);
+            }
+        }
+    }
+
+    /**
+     * Returns the name of the directory for this webapp.
+     * @param identifier ID for the webapp.  Used as a subdirectory name.
+     * @return File for storing information about the webapp.
+     */
+    public static File getWebappDirectory(String identifier) {
+        Context context = ApplicationStatus.getApplicationContext();
+        File baseDirectory = context.getDir(WEBAPP_DIRECTORY_NAME, Context.MODE_PRIVATE);
+        File webappDirectory = new File(baseDirectory, identifier);
+        if (!webappDirectory.exists() && !webappDirectory.mkdir()) {
+            Log.e(TAG, "Failed to create webapp directory.");
+        }
+        return webappDirectory;
+    }
+}