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http://hi-android.info/src/android/content/SyncManager.java.html

 

SyncManager.java

/*
 * Copyright (C) 2008 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 android.content;

import com.android.internal.R;
import com.android.internal.util.ArrayUtils;

import android.accounts.Account;
import android.accounts.AccountManager;
import android.accounts.OnAccountsUpdateListener;
import android.app.AlarmManager;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.content.pm.RegisteredServicesCache;
import android.content.pm.ProviderInfo;
import android.content.pm.RegisteredServicesCacheListener;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Bundle;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.IBinder;
import android.os.Looper;
import android.os.Message;
import android.os.PowerManager;
import android.os.Process;
import android.os.RemoteException;
import android.os.SystemClock;
import android.os.SystemProperties;
import android.os.WorkSource;
import android.provider.Settings;
import android.text.format.DateUtils;
import android.text.format.Time;
import android.util.EventLog;
import android.util.Log;
import android.util.Pair;

import java.io.FileDescriptor;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Random;
import java.util.Collection;
import java.util.concurrent.CountDownLatch;

/**
 * @hide
 */
public class SyncManager implements OnAccountsUpdateListener {
    private static final String TAG = "SyncManager";

    /** Delay a sync due to local changes this long. In milliseconds */
    private static final long LOCAL_SYNC_DELAY;

    /**
     * If a sync takes longer than this and the sync queue is not empty then we will
     * cancel it and add it back to the end of the sync queue. In milliseconds.
     */
    private static final long MAX_TIME_PER_SYNC;

    static {
        String localSyncDelayString = SystemProperties.get("sync.local_sync_delay");
        long localSyncDelay = 30 * 1000; // 30 seconds
        if (localSyncDelayString != null) {
            try {
                localSyncDelay = Long.parseLong(localSyncDelayString);
            } catch (NumberFormatException nfe) {
                // ignore, use default
            }
        }
        LOCAL_SYNC_DELAY = localSyncDelay;

        String maxTimePerSyncString = SystemProperties.get("sync.max_time_per_sync");
        long maxTimePerSync = 5 * 60 * 1000; // 5 minutes
        if (maxTimePerSyncString != null) {
            try {
                maxTimePerSync = Long.parseLong(maxTimePerSyncString);
            } catch (NumberFormatException nfe) {
                // ignore, use default
            }
        }
        MAX_TIME_PER_SYNC = maxTimePerSync;
    }

    private static final long SYNC_NOTIFICATION_DELAY = 30 * 1000; // 30 seconds

    /**
     * When retrying a sync for the first time use this delay. After that
     * the retry time will double until it reached MAX_SYNC_RETRY_TIME.
     * In milliseconds.
     */
    private static final long INITIAL_SYNC_RETRY_TIME_IN_MS = 30 * 1000; // 30 seconds

    /**
     * Default the max sync retry time to this value.
     */
    private static final long DEFAULT_MAX_SYNC_RETRY_TIME_IN_SECONDS = 60 * 60; // one hour

    /**
     * How long to wait before retrying a sync that failed due to one already being in progress.
     */
    private static final int DELAY_RETRY_SYNC_IN_PROGRESS_IN_SECONDS = 10;

    /**
     * An error notification is sent if sync of any of the providers has been failing for this long.
     */
    private static final long ERROR_NOTIFICATION_DELAY_MS = 1000 * 60 * 10; // 10 minutes

    private static final int INITIALIZATION_UNBIND_DELAY_MS = 5000;

    private static final String SYNC_WAKE_LOCK = "*sync*";
    private static final String HANDLE_SYNC_ALARM_WAKE_LOCK = "SyncManagerHandleSyncAlarm";

    private Context mContext;

    private volatile Account[] mAccounts = INITIAL_ACCOUNTS_ARRAY;

    volatile private PowerManager.WakeLock mSyncWakeLock;
    volatile private PowerManager.WakeLock mHandleAlarmWakeLock;
    volatile private boolean mDataConnectionIsConnected = false;
    volatile private boolean mStorageIsLow = false;

    private final NotificationManager mNotificationMgr;
    private AlarmManager mAlarmService = null;

    private final SyncStorageEngine mSyncStorageEngine;
    public final SyncQueue mSyncQueue;

    private ActiveSyncContext mActiveSyncContext = null;

    // set if the sync error indicator should be reported.
    private boolean mNeedSyncErrorNotification = false;
    // set if the sync active indicator should be reported
    private boolean mNeedSyncActiveNotification = false;

    private final PendingIntent mSyncAlarmIntent;
    // Synchronized on "this". Instead of using this directly one should instead call
    // its accessor, getConnManager().
    private ConnectivityManager mConnManagerDoNotUseDirectly;

    private final SyncAdaptersCache mSyncAdapters;

    private BroadcastReceiver mStorageIntentReceiver =
            new BroadcastReceiver() {
                public void onReceive(Context context, Intent intent) {
                    String action = intent.getAction();
                    if (Intent.ACTION_DEVICE_STORAGE_LOW.equals(action)) {
                        if (Log.isLoggable(TAG, Log.VERBOSE)) {
                            Log.v(TAG, "Internal storage is low.");
                        }
                        mStorageIsLow = true;
                        cancelActiveSync(null /* any account */, null /* any authority */);
                    } else if (Intent.ACTION_DEVICE_STORAGE_OK.equals(action)) {
                        if (Log.isLoggable(TAG, Log.VERBOSE)) {
                            Log.v(TAG, "Internal storage is ok.");
                        }
                        mStorageIsLow = false;
                        sendCheckAlarmsMessage();
                    }
                }
            };

    private BroadcastReceiver mBootCompletedReceiver = new BroadcastReceiver() {
        public void onReceive(Context context, Intent intent) {
            mSyncHandler.onBootCompleted();
        }
    };

    private BroadcastReceiver mBackgroundDataSettingChanged = new BroadcastReceiver() {
        public void onReceive(Context context, Intent intent) {
            if (getConnectivityManager().getBackgroundDataSetting()) {
                scheduleSync(null /* account */, null /* authority */, new Bundle(), 0 /* delay */,
                        false /* onlyThoseWithUnknownSyncableState */);
            }
        }
    };

    private static final Account[] INITIAL_ACCOUNTS_ARRAY = new Account[0];

    public void onAccountsUpdated(Account[] accounts) {
        // remember if this was the first time this was called after an update
        final boolean justBootedUp = mAccounts == INITIAL_ACCOUNTS_ARRAY;
        mAccounts = accounts;

        // if a sync is in progress yet it is no longer in the accounts list,
        // cancel it
        ActiveSyncContext activeSyncContext = mActiveSyncContext;
        if (activeSyncContext != null) {
            if (!ArrayUtils.contains(accounts, activeSyncContext.mSyncOperation.account)) {
                Log.d(TAG, "canceling sync since the account has been removed");
                sendSyncFinishedOrCanceledMessage(activeSyncContext,
                        null /* no result since this is a cancel */);
            }
        }

        // we must do this since we don't bother scheduling alarms when
        // the accounts are not set yet
        sendCheckAlarmsMessage();

        if (mBootCompleted) {
            mSyncStorageEngine.doDatabaseCleanup(accounts);
        }

        if (accounts.length > 0) {
            // If this is the first time this was called after a bootup then
            // the accounts haven't really changed, instead they were just loaded
            // from the AccountManager. Otherwise at least one of the accounts
            // has a change.
            //
            // If there was a real account change then force a sync of all accounts.
            // This is a bit of overkill, but at least it will end up retrying syncs
            // that failed due to an authentication failure and thus will recover if the
            // account change was a password update.
            //
            // If this was the bootup case then don't sync everything, instead only
            // sync those that have an unknown syncable state, which will give them
            // a chance to set their syncable state.
            boolean onlyThoseWithUnkownSyncableState = justBootedUp;
            scheduleSync(null, null, null, 0 /* no delay */, onlyThoseWithUnkownSyncableState);
        }
    }

    private BroadcastReceiver mConnectivityIntentReceiver =
            new BroadcastReceiver() {
        public void onReceive(Context context, Intent intent) {
            NetworkInfo networkInfo =
                    intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
            NetworkInfo.State state = (networkInfo == null ? NetworkInfo.State.UNKNOWN :
                    networkInfo.getState());
            if (Log.isLoggable(TAG, Log.VERBOSE)) {
                Log.v(TAG, "received connectivity action.  network info: " + networkInfo);
            }

            // only pay attention to the CONNECTED and DISCONNECTED states.
            // if connected, we are connected.
            // if disconnected, we may not be connected.  in some cases, we may be connected on
            // a different network.
            // e.g., if switching from GPRS to WiFi, we may receive the CONNECTED to WiFi and
            // DISCONNECTED for GPRS in any order.  if we receive the CONNECTED first, and then
            // a DISCONNECTED, we want to make sure we set mDataConnectionIsConnected to true
            // since we still have a WiFi connection.
            switch (state) {
                case CONNECTED:
                    mDataConnectionIsConnected = true;
                    break;
                case DISCONNECTED:
                    if (intent.getBooleanExtra(ConnectivityManager.EXTRA_NO_CONNECTIVITY, false)) {
                        mDataConnectionIsConnected = false;
                    } else {
                        mDataConnectionIsConnected = true;
                    }
                    break;
                default:
                    // ignore the rest of the states -- leave our boolean alone.
            }
            if (mDataConnectionIsConnected) {
                sendCheckAlarmsMessage();
            }
        }
    };

    private BroadcastReceiver mShutdownIntentReceiver =
            new BroadcastReceiver() {
        public void onReceive(Context context, Intent intent) {
            Log.w(TAG, "Writing sync state before shutdown...");
            getSyncStorageEngine().writeAllState();
        }
    };

    private static final String ACTION_SYNC_ALARM = "android.content.syncmanager.SYNC_ALARM";
    private final SyncHandler mSyncHandler;
    private final Handler mMainHandler;

    private volatile boolean mBootCompleted = false;

    private ConnectivityManager getConnectivityManager() {
        synchronized (this) {
            if (mConnManagerDoNotUseDirectly == null) {
                mConnManagerDoNotUseDirectly = (ConnectivityManager)mContext.getSystemService(
                        Context.CONNECTIVITY_SERVICE);
            }
            return mConnManagerDoNotUseDirectly;
        }
    }

    public SyncManager(Context context, boolean factoryTest) {
        // Initialize the SyncStorageEngine first, before registering observers
        // and creating threads and so on; it may fail if the disk is full.
        SyncStorageEngine.init(context);
        mSyncStorageEngine = SyncStorageEngine.getSingleton();
        mSyncQueue = new SyncQueue(mSyncStorageEngine);

        mContext = context;

        HandlerThread syncThread = new HandlerThread("SyncHandlerThread",
                Process.THREAD_PRIORITY_BACKGROUND);
        syncThread.start();
        mSyncHandler = new SyncHandler(syncThread.getLooper());
        mMainHandler = new Handler(mContext.getMainLooper());

        mSyncAdapters = new SyncAdaptersCache(mContext);
        mSyncAdapters.setListener(new RegisteredServicesCacheListener<SyncAdapterType>() {
            public void onServiceChanged(SyncAdapterType type, boolean removed) {
                if (!removed) {
                    scheduleSync(null, type.authority, null, 0 /* no delay */,
                            false /* onlyThoseWithUnkownSyncableState */);
                }
            }
        }, mSyncHandler);

        mSyncAlarmIntent = PendingIntent.getBroadcast(
                mContext, 0 /* ignored */, new Intent(ACTION_SYNC_ALARM), 0);

        IntentFilter intentFilter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
        context.registerReceiver(mConnectivityIntentReceiver, intentFilter);

        if (!factoryTest) {
            intentFilter = new IntentFilter(Intent.ACTION_BOOT_COMPLETED);
            context.registerReceiver(mBootCompletedReceiver, intentFilter);
        }

        intentFilter = new IntentFilter(ConnectivityManager.ACTION_BACKGROUND_DATA_SETTING_CHANGED);
        context.registerReceiver(mBackgroundDataSettingChanged, intentFilter);

        intentFilter = new IntentFilter(Intent.ACTION_DEVICE_STORAGE_LOW);
        intentFilter.addAction(Intent.ACTION_DEVICE_STORAGE_OK);
        context.registerReceiver(mStorageIntentReceiver, intentFilter);

        intentFilter = new IntentFilter(Intent.ACTION_SHUTDOWN);
        intentFilter.setPriority(100);
        context.registerReceiver(mShutdownIntentReceiver, intentFilter);

        if (!factoryTest) {
            mNotificationMgr = (NotificationManager)
                context.getSystemService(Context.NOTIFICATION_SERVICE);
            context.registerReceiver(new SyncAlarmIntentReceiver(),
                    new IntentFilter(ACTION_SYNC_ALARM));
        } else {
            mNotificationMgr = null;
        }
        PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
        mSyncWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, SYNC_WAKE_LOCK);
        mSyncWakeLock.setReferenceCounted(false);

        // This WakeLock is used to ensure that we stay awake between the time that we receive
        // a sync alarm notification and when we finish processing it. We need to do this
        // because we don't do the work in the alarm handler, rather we do it in a message
        // handler.
        mHandleAlarmWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK,
                HANDLE_SYNC_ALARM_WAKE_LOCK);
        mHandleAlarmWakeLock.setReferenceCounted(false);

        mSyncStorageEngine.addStatusChangeListener(
                ContentResolver.SYNC_OBSERVER_TYPE_SETTINGS, new ISyncStatusObserver.Stub() {
            public void onStatusChanged(int which) {
                // force the sync loop to run if the settings change
                sendCheckAlarmsMessage();
            }
        });

        if (!factoryTest) {
            AccountManager.get(mContext).addOnAccountsUpdatedListener(SyncManager.this,
                mSyncHandler, false /* updateImmediately */);
            // do this synchronously to ensure we have the accounts before this call returns
            onAccountsUpdated(AccountManager.get(mContext).getAccounts());
        }
    }

    /**
     * Return a random value v that satisfies minValue <= v < maxValue. The difference between
     * maxValue and minValue must be less than Integer.MAX_VALUE.
     */
    private long jitterize(long minValue, long maxValue) {
        Random random = new Random(SystemClock.elapsedRealtime());
        long spread = maxValue - minValue;
        if (spread > Integer.MAX_VALUE) {
            throw new IllegalArgumentException("the difference between the maxValue and the "
                    + "minValue must be less than " + Integer.MAX_VALUE);
        }
        return minValue + random.nextInt((int)spread);
    }

    public SyncStorageEngine getSyncStorageEngine() {
        return mSyncStorageEngine;
    }

    private void ensureAlarmService() {
        if (mAlarmService == null) {
            mAlarmService = (AlarmManager)mContext.getSystemService(Context.ALARM_SERVICE);
        }
    }

    private void initializeSyncAdapter(Account account, String authority) {
        if (Log.isLoggable(TAG, Log.VERBOSE)) {
            Log.v(TAG, "initializeSyncAdapter: " + account + ", authority " + authority);
        }
        SyncAdapterType syncAdapterType = SyncAdapterType.newKey(authority, account.type);
        RegisteredServicesCache.ServiceInfo<SyncAdapterType> syncAdapterInfo =
                mSyncAdapters.getServiceInfo(syncAdapterType);
        if (syncAdapterInfo == null) {
            Log.w(TAG, "can't find a sync adapter for " + syncAdapterType + ", removing");
            mSyncStorageEngine.removeAuthority(account, authority);
            return;
        }

        Intent intent = new Intent();
        intent.setAction("android.content.SyncAdapter");
        intent.setComponent(syncAdapterInfo.componentName);
        if (!mContext.bindService(intent, new InitializerServiceConnection(account, authority, mContext,
                mMainHandler),
                Context.BIND_AUTO_CREATE | Context.BIND_NOT_FOREGROUND)) {
            Log.w(TAG, "initializeSyncAdapter: failed to bind to " + intent);
        }
    }

    private static class InitializerServiceConnection implements ServiceConnection {
        private final Account mAccount;
        private final String mAuthority;
        private final Handler mHandler;
        private volatile Context mContext;
        private volatile boolean mInitialized;

        public InitializerServiceConnection(Account account, String authority, Context context,
                Handler handler) {
            mAccount = account;
            mAuthority = authority;
            mContext = context;
            mHandler = handler;
            mInitialized = false;
        }

        public void onServiceConnected(ComponentName name, IBinder service) {
            try {
                if (!mInitialized) {
                    mInitialized = true;
                    if (Log.isLoggable(TAG, Log.VERBOSE)) {
                        Log.v(TAG, "calling initialize: " + mAccount + ", authority " + mAuthority);
                    }
                    ISyncAdapter.Stub.asInterface(service).initialize(mAccount, mAuthority);
                }
            } catch (RemoteException e) {
                // doesn't matter, we will retry again later
                Log.d(TAG, "error while initializing: " + mAccount + ", authority " + mAuthority,
                        e);
            } finally {
                // give the sync adapter time to initialize before unbinding from it
                // TODO: change this API to not rely on this timing, http://b/2500805
                mHandler.postDelayed(new Runnable() {
                    public void run() {
                        if (mContext != null) {
                            mContext.unbindService(InitializerServiceConnection.this);
                            mContext = null;
                        }
                    }
                }, INITIALIZATION_UNBIND_DELAY_MS);
            }
        }

        public void onServiceDisconnected(ComponentName name) {
            if (mContext != null) {
                mContext.unbindService(InitializerServiceConnection.this);
                mContext = null;
            }
        }

    }

    /**
     * Initiate a sync. This can start a sync for all providers
     * (pass null to url, set onlyTicklable to false), only those
     * providers that are marked as ticklable (pass null to url,
     * set onlyTicklable to true), or a specific provider (set url
     * to the content url of the provider).
     *
     * <p>If the ContentResolver.SYNC_EXTRAS_UPLOAD boolean in extras is
     * true then initiate a sync that just checks for local changes to send
     * to the server, otherwise initiate a sync that first gets any
     * changes from the server before sending local changes back to
     * the server.
     *
     * <p>If a specific provider is being synced (the url is non-null)
     * then the extras can contain SyncAdapter-specific information
     * to control what gets synced (e.g. which specific feed to sync).
     *
     * <p>You'll start getting callbacks after this.
     *
     * @param requestedAccount the account to sync, may be null to signify all accounts
     * @param requestedAuthority the authority to sync, may be null to indicate all authorities
     * @param extras a Map of SyncAdapter-specific information to control
*          syncs of a specific provider. Can be null. Is ignored
*          if the url is null.
     * @param delay how many milliseconds in the future to wait before performing this
     * @param onlyThoseWithUnkownSyncableState
     */
    public void scheduleSync(Account requestedAccount, String requestedAuthority,
            Bundle extras, long delay, boolean onlyThoseWithUnkownSyncableState) {
        boolean isLoggable = Log.isLoggable(TAG, Log.VERBOSE);

        final boolean backgroundDataUsageAllowed = !mBootCompleted ||
                getConnectivityManager().getBackgroundDataSetting();

        if (extras == null) extras = new Bundle();

        Boolean expedited = extras.getBoolean(ContentResolver.SYNC_EXTRAS_EXPEDITED, false);
        if (expedited) {
            delay = -1; // this means schedule at the front of the queue
        }

        Account[] accounts;
        if (requestedAccount != null) {
            accounts = new Account[]{requestedAccount};
        } else {
            // if the accounts aren't configured yet then we can't support an account-less
            // sync request
            accounts = mAccounts;
            if (accounts.length == 0) {
                if (isLoggable) {
                    Log.v(TAG, "scheduleSync: no accounts configured, dropping");
                }
                return;
            }
        }

        final boolean uploadOnly = extras.getBoolean(ContentResolver.SYNC_EXTRAS_UPLOAD, false);
        final boolean manualSync = extras.getBoolean(ContentResolver.SYNC_EXTRAS_MANUAL, false);
        if (manualSync) {
            extras.putBoolean(ContentResolver.SYNC_EXTRAS_IGNORE_BACKOFF, true);
            extras.putBoolean(ContentResolver.SYNC_EXTRAS_IGNORE_SETTINGS, true);
        }
        final boolean ignoreSettings =
                extras.getBoolean(ContentResolver.SYNC_EXTRAS_IGNORE_SETTINGS, false);

        int source;
        if (uploadOnly) {
            source = SyncStorageEngine.SOURCE_LOCAL;
        } else if (manualSync) {
            source = SyncStorageEngine.SOURCE_USER;
        } else if (requestedAuthority == null) {
            source = SyncStorageEngine.SOURCE_POLL;
        } else {
            // this isn't strictly server, since arbitrary callers can (and do) request
            // a non-forced two-way sync on a specific url
            source = SyncStorageEngine.SOURCE_SERVER;
        }

        // Compile a list of authorities that have sync adapters.
        // For each authority sync each account that matches a sync adapter.
        final HashSet<String> syncableAuthorities = new HashSet<String>();
        for (RegisteredServicesCache.ServiceInfo<SyncAdapterType> syncAdapter :
                mSyncAdapters.getAllServices()) {
            syncableAuthorities.add(syncAdapter.type.authority);
        }

        // if the url was specified then replace the list of authorities with just this authority
        // or clear it if this authority isn't syncable
        fo

  


  

    
    
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