/*
* Copyright (C) 2013 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 com.android.settings.location;
import android.app.ActivityManager;
import android.content.Context;
import android.content.Intent;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.content.pm.ServiceInfo;
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.content.res.XmlResourceParser;
import android.graphics.drawable.Drawable;
import android.location.SettingInjectorService;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.os.Messenger;
import android.os.SystemClock;
import android.os.UserHandle;
import android.os.UserManager;
import android.support.v7.preference.Preference;
import android.util.AttributeSet;
import android.util.Log;
import android.util.Xml;
import com.android.settings.DimmableIconPreference;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
/**
* Adds the preferences specified by the {@link InjectedSetting} objects to a preference group.
*
* Duplicates some code from {@link android.content.pm.RegisteredServicesCache}. We do not use that
* class directly because it is not a good match for our use case: we do not need the caching, and
* so do not want the additional resource hit at app install/upgrade time; and we would have to
* suppress the tie-breaking between multiple services reporting settings with the same name.
* Code-sharing would require extracting {@link
* android.content.pm.RegisteredServicesCache#parseServiceAttributes(android.content.res.Resources,
* String, android.util.AttributeSet)} into an interface, which didn't seem worth it.
*/
class SettingsInjector {
static final String TAG = "SettingsInjector";
/**
* If reading the status of a setting takes longer than this, we go ahead and start reading
* the next setting.
*/
private static final long INJECTED_STATUS_UPDATE_TIMEOUT_MILLIS = 1000;
/**
* {@link Message#what} value for starting to load status values
* in case we aren't already in the process of loading them.
*/
private static final int WHAT_RELOAD = 1;
/**
* {@link Message#what} value sent after receiving a status message.
*/
private static final int WHAT_RECEIVED_STATUS = 2;
/**
* {@link Message#what} value sent after the timeout waiting for a status message.
*/
private static final int WHAT_TIMEOUT = 3;
private final Context mContext;
/**
* The settings that were injected
*/
private final Set<Setting> mSettings;
private final Handler mHandler;
public SettingsInjector(Context context) {
mContext = context;
mSettings = new HashSet<Setting>();
mHandler = new StatusLoadingHandler();
}
/**
* Returns a list for a profile with one {@link InjectedSetting} object for each
* {@link android.app.Service} that responds to
* {@link SettingInjectorService#ACTION_SERVICE_INTENT} and provides the expected setting
* metadata.
*
* Duplicates some code from {@link android.content.pm.RegisteredServicesCache}.
*
* TODO: unit test
*/
private List<InjectedSetting> getSettings(final UserHandle userHandle) {
PackageManager pm = mContext.getPackageManager();
Intent intent = new Intent(SettingInjectorService.ACTION_SERVICE_INTENT);
final int profileId = userHandle.getIdentifier();
List<ResolveInfo> resolveInfos =
pm.queryIntentServicesAsUser(intent, PackageManager.GET_META_DATA, profileId);
if (Log.isLoggable(TAG, Log.DEBUG)) {
Log.d(TAG, "Found services for profile id " + profileId + ": " + resolveInfos);
}
List<InjectedSetting> settings = new ArrayList<InjectedSetting>(resolveInfos.size());
for (ResolveInfo resolveInfo : resolveInfos) {
try {
InjectedSetting setting = parseServiceInfo(resolveInfo, userHandle, pm);
if (setting == null) {
Log.w(TAG, "Unable to load service info " + resolveInfo);
} else {
settings.add(setting);
}
} catch (XmlPullParserException e) {
Log.w(TAG, "Unable to load service info " + resolveInfo, e);
} catch (IOException e) {
Log.w(TAG, "Unable to load service info " + resolveInfo, e);
}
}
if (Log.isLoggable(TAG, Log.DEBUG)) {
Log.d(TAG, "Loaded settings for profile id " + profileId + ": " + settings);
}
return settings;
}
/**
* Returns the settings parsed from the attributes of the
* {@link SettingInjectorService#META_DATA_NAME} tag, or null.
*
* Duplicates some code from {@link android.content.pm.RegisteredServicesCache}.
*/
private static InjectedSetting parseServiceInfo(ResolveInfo service, UserHandle userHandle,
PackageManager pm) throws XmlPullParserException, IOException {
ServiceInfo si = service.serviceInfo;
ApplicationInfo ai = si.applicationInfo;
if ((ai.flags & ApplicationInfo.FLAG_SYSTEM) == 0) {
if (Log.isLoggable(TAG, Log.WARN)) {
Log.w(TAG, "Ignoring attempt to inject setting from app not in system image: "
+ service);
return null;
}
}
XmlResourceParser parser = null;
try {
parser = si.loadXmlMetaData(pm, SettingInjectorService.META_DATA_NAME);
if (parser == null) {
throw new XmlPullParserException("No " + SettingInjectorService.META_DATA_NAME
+ " meta-data for " + service + ": " + si);
}
AttributeSet attrs = Xml.asAttributeSet(parser);
int type;
while ((type = parser.next()) != XmlPullParser.END_DOCUMENT
&& type != XmlPullParser.START_TAG) {
}
String nodeName = parser.getName();
if (!SettingInjectorService.ATTRIBUTES_NAME.equals(nodeName)) {
throw new XmlPullParserException("Meta-data does not start with "
+ SettingInjectorService.ATTRIBUTES_NAME + " tag");
}
Resources res = pm.getResourcesForApplicationAsUser(si.packageName,
userHandle.getIdentifier());
return parseAttributes(si.packageName, si.name, userHandle, res, attrs);
} catch (PackageManager.NameNotFoundException e) {
throw new XmlPullParserException(
"Unable to load resources for package " + si.packageName);
} finally {
if (parser != null) {
parser.close();
}
}
}
/**
* Returns an immutable representation of the static attributes for the setting, or null.
*/
private static InjectedSetting parseAttributes(String packageName, String className,
UserHandle userHandle, Resources res, AttributeSet attrs) {
TypedArray sa = res.obtainAttributes(attrs, android.R.styleable.SettingInjectorService);
try {
// Note that to help guard against malicious string injection, we do not allow dynamic
// specification of the label (setting title)
final String title = sa.getString(android.R.styleable.SettingInjectorService_title);
final int iconId =
sa.getResourceId(android.R.styleable.SettingInjectorService_icon, 0);
final String settingsActivity =
sa.getString(android.R.styleable.SettingInjectorService_settingsActivity);
if (Log.isLoggable(TAG, Log.DEBUG)) {
Log.d(TAG, "parsed title: " + title + ", iconId: " + iconId
+ ", settingsActivity: " + settingsActivity);
}
return InjectedSetting.newInstance(packageName, className,
title, iconId, userHandle, settingsActivity);
} finally {
sa.recycle();
}
}
/**
* Gets a list of preferences that other apps have injected.
*
* @param profileId Identifier of the user/profile to obtain the injected settings for or
* UserHandle.USER_CURRENT for all profiles associated with current user.
*/
public List<Preference> getInjectedSettings(final int profileId) {
final UserManager um = (UserManager) mContext.getSystemService(Context.USER_SERVICE);
final List<UserHandle> profiles = um.getUserProfiles();
ArrayList<Preference> prefs = new ArrayList<Preference>();
final int profileCount = profiles.size();
for (int i = 0; i < profileCount; ++i) {
final UserHandle userHandle = profiles.get(i);
if (profileId == UserHandle.USER_CURRENT || profileId == userHandle.getIdentifier()) {
Iterable<InjectedSetting> settings = getSettings(userHandle);
for (InjectedSetting setting : settings) {
Preference pref = addServiceSetting(prefs, setting);
mSettings.add(new Setting(setting, pref));
}
}
}
reloadStatusMessages();
return prefs;
}
/**
* Reloads the status messages for all the preference items.
*/
public void reloadStatusMessages() {
if (Log.isLoggable(TAG, Log.DEBUG)) {
Log.d(TAG, "reloadingStatusMessages: " + mSettings);
}
mHandler.sendMessage(mHandler.obtainMessage(WHAT_RELOAD));
}
/**
* Adds an injected setting to the root.
*/
private Preference addServiceSetting(List<Preference> prefs, InjectedSetting info) {
PackageManager pm = mContext.getPackageManager();
Drawable appIcon = pm.getDrawable(info.packageName, info.iconId, null);
Drawable icon = pm.getUserBadgedIcon(appIcon, info.mUserHandle);
CharSequence badgedAppLabel = pm.getUserBadgedLabel(info.title, info.mUserHandle);
if (info.title.contentEquals(badgedAppLabel)) {
// If badged label is not different from original then no need for it as
// a separate content description.
badgedAppLabel = null;
}
Preference pref = new DimmableIconPreference(mContext, badgedAppLabel);
pref.setTitle(info.title);
pref.setSummary(null);
pref.setIcon(icon);
pref.setOnPreferenceClickListener(new ServiceSettingClickedListener(info));
prefs.add(pref);
return pref;
}
private class ServiceSettingClickedListener
implements Preference.OnPreferenceClickListener {
private InjectedSetting mInfo;
public ServiceSettingClickedListener(InjectedSetting info) {
mInfo = info;
}
@Override
public boolean onPreferenceClick(Preference preference) {
// Activity to start if they click on the preference. Must start in new task to ensure
// that "android.settings.LOCATION_SOURCE_SETTINGS" brings user back to
// Settings > Location.
Intent settingIntent = new Intent();
settingIntent.setClassName(mInfo.packageName, mInfo.settingsActivity);
// Sometimes the user may navigate back to "Settings" and launch another different
// injected setting after one injected setting has been launched.
//
// FLAG_ACTIVITY_CLEAR_TOP allows multiple Activities to stack on each other. When
// "back" button is clicked, the user will navigate through all the injected settings
// launched before. Such behavior could be quite confusing sometimes.
//
// In order to avoid such confusion, we use FLAG_ACTIVITY_CLEAR_TASK, which always clear
// up all existing injected settings and make sure that "back" button always brings the
// user back to "Settings" directly.
settingIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
mContext.startActivityAsUser(settingIntent, mInfo.mUserHandle);
return true;
}
}
/**
* Loads the setting status values one at a time. Each load starts a subclass of {@link
* SettingInjectorService}, so to reduce memory pressure we don't want to load too many at
* once.
*/
private final class StatusLoadingHandler extends Handler {
/**
* Settings whose status values need to be loaded. A set is used to prevent redundant loads.
*/
private Set<Setting> mSettingsToLoad = new HashSet<Setting>();
/**
* Settings that are being loaded now and haven't timed out. In practice this should have
* zero or one elements.
*/
private Set<Setting> mSettingsBeingLoaded = new HashSet<Setting>();
/**
* Settings that are being loaded but have timed out. If only one setting has timed out, we
* will go ahead and start loading the next setting so that one slow load won't delay the
* load of the other settings.
*/
private Set<Setting> mTimedOutSettings = new HashSet<Setting>();
private boolean mReloadRequested;
@Override
public void handleMessage(Message msg) {
if (Log.isLoggable(TAG, Log.DEBUG)) {
Log.d(TAG, "handleMessage start: " + msg + ", " + this);
}
// Update state in response to message
switch (msg.what) {
case WHAT_RELOAD:
mReloadRequested = true;
break;
case WHAT_RECEIVED_STATUS:
final Setting receivedSetting = (Setting) msg.obj;
receivedSetting.maybeLogElapsedTime();
mSettingsBeingLoaded.remove(receivedSetting);
mTimedOutSettings.remove(receivedSetting);
removeMessages(WHAT_TIMEOUT, receivedSetting);
break;
case WHAT_TIMEOUT:
final Setting timedOutSetting = (Setting) msg.obj;
mSettingsBeingLoaded.remove(timedOutSetting);
mTimedOutSettings.add(timedOutSetting);
if (Log.isLoggable(TAG, Log.WARN)) {
Log.w(TAG, "Timed out after " + timedOutSetting.getElapsedTime()
+ " millis trying to get status for: " + timedOutSetting);
}
break;
default:
Log.wtf(TAG, "Unexpected what: " + msg);
}
// Decide whether to load additional settings based on the new state. Start by seeing
// if we have headroom to load another setting.
if (mSettingsBeingLoaded.size() > 0 || mTimedOutSettings.size() > 1) {
// Don't load any more settings until one of the pending settings has completed.
// To reduce memory pressure, we want to be loading at most one setting (plus at
// most one timed-out setting) at a time. This means we'll be responsible for
// bringing in at most two services.
if (Log.isLoggable(TAG, Log.VERBOSE)) {
Log.v(TAG, "too many services already live for " + msg + ", " + this);
}
return;
}
if (mReloadRequested && mSettingsToLoad.isEmpty() && mSettingsBeingLoaded.isEmpty()
&& mTimedOutSettings.isEmpty()) {
if (Log.isLoggable(TAG, Log.VERBOSE)) {
Log.v(TAG, "reloading because idle and reload requesteed " + msg + ", " + this);
}
// Reload requested, so must reload all settings
mSettingsToLoad.addAll(mSettings);
mReloadRequested = false;
}
// Remove the next setting to load from the queue, if any
Iterator<Setting> iter = mSettingsToLoad.iterator();
if (!iter.hasNext()) {
if (Log.isLoggable(TAG, Log.VERBOSE)) {
Log.v(TAG, "nothing left to do for " + msg + ", " + this);
}
return;
}
Setting setting = iter.next();
iter.remove();
// Request the status value
setting.startService();
mSettingsBeingLoaded.add(setting);
// Ensure that if receiving the status value takes too long, we start loading the
// next value anyway
Message timeoutMsg = obtainMessage(WHAT_TIMEOUT, setting);
sendMessageDelayed(timeoutMsg, INJECTED_STATUS_UPDATE_TIMEOUT_MILLIS);
if (Log.isLoggable(TAG, Log.DEBUG)) {
Log.d(TAG, "handleMessage end " + msg + ", " + this
+ ", started loading " + setting);
}
}
@Override
public String toString() {
return "StatusLoadingHandler{" +
"mSettingsToLoad=" + mSettingsToLoad +
", mSettingsBeingLoaded=" + mSettingsBeingLoaded +
", mTimedOutSettings=" + mTimedOutSettings +
", mReloadRequested=" + mReloadRequested +
'}';
}
}
/**
* Represents an injected setting and the corresponding preference.
*/
private final class Setting {
public final InjectedSetting setting;
public final Preference preference;
public long startMillis;
private Setting(InjectedSetting setting, Preference preference) {
this.setting = setting;
this.preference = preference;
}
@Override
public String toString() {
return "Setting{" +
"setting=" + setting +
", preference=" + preference +
'}';
}
/**
* Returns true if they both have the same {@link #setting} value. Ignores mutable
* {@link #preference} and {@link #startMillis} so that it's safe to use in sets.
*/
@Override
public boolean equals(Object o) {
return this == o || o instanceof Setting && setting.equals(((Setting) o).setting);
}
@Override
public int hashCode() {
return setting.hashCode();
}
/**
* Starts the service to fetch for the current status for the setting, and updates the
* preference when the service replies.
*/
public void startService() {
final ActivityManager am = (ActivityManager)
mContext.getSystemService(Context.ACTIVITY_SERVICE);
if (!am.isUserRunning(setting.mUserHandle.getIdentifier())) {
if (Log.isLoggable(TAG, Log.VERBOSE)) {
Log.v(TAG, "Cannot start service as user "
+ setting.mUserHandle.getIdentifier() + " is not running");
}
return;
}
Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
Bundle bundle = msg.getData();
boolean enabled = bundle.getBoolean(SettingInjectorService.ENABLED_KEY, true);
if (Log.isLoggable(TAG, Log.DEBUG)) {
Log.d(TAG, setting + ": received " + msg + ", bundle: " + bundle);
}
preference.setSummary(null);
preference.setEnabled(enabled);
mHandler.sendMessage(
mHandler.obtainMessage(WHAT_RECEIVED_STATUS, Setting.this));
}
};
Messenger messenger = new Messenger(handler);
Intent intent = setting.getServiceIntent();
intent.putExtra(SettingInjectorService.MESSENGER_KEY, messenger);
if (Log.isLoggable(TAG, Log.DEBUG)) {
Log.d(TAG, setting + ": sending update intent: " + intent
+ ", handler: " + handler);
startMillis = SystemClock.elapsedRealtime();
} else {
startMillis = 0;
}
// Start the service, making sure that this is attributed to the user associated with
// the setting rather than the system user.
mContext.startServiceAsUser(intent, setting.mUserHandle);
}
public long getElapsedTime() {
long end = SystemClock.elapsedRealtime();
return end - startMillis;
}
public void maybeLogElapsedTime() {
if (Log.isLoggable(TAG, Log.DEBUG) && startMillis != 0) {
long elapsed = getElapsedTime();
Log.d(TAG, this + " update took " + elapsed + " millis");
}
}
}
}