diff options
author | Amith Yamasani <yamasani@google.com> | 2013-11-22 08:25:26 -0800 |
---|---|---|
committer | Amith Yamasani <yamasani@google.com> | 2013-12-19 15:25:37 -0800 |
commit | 9158825f9c41869689d6b1786d7c7aa8bdd524ce (patch) | |
tree | f41944461539f0c70030668b4558296469c307d3 /services/core/java/com/android/server/NetworkTimeUpdateService.java | |
parent | 30d032928a294fbb6f385e9d0367a75b7bf2649b (diff) | |
download | frameworks_base-9158825f9c41869689d6b1786d7c7aa8bdd524ce.zip frameworks_base-9158825f9c41869689d6b1786d7c7aa8bdd524ce.tar.gz frameworks_base-9158825f9c41869689d6b1786d7c7aa8bdd524ce.tar.bz2 |
Move some system services to separate directories
Refactored the directory structure so that services can be optionally
excluded. This is step 1. Will be followed by another change that makes
it possible to remove services from the build.
Change-Id: Ideacedfd34b5e213217ad3ff4ebb21c4a8e73f85
Diffstat (limited to 'services/core/java/com/android/server/NetworkTimeUpdateService.java')
-rw-r--r-- | services/core/java/com/android/server/NetworkTimeUpdateService.java | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/services/core/java/com/android/server/NetworkTimeUpdateService.java b/services/core/java/com/android/server/NetworkTimeUpdateService.java new file mode 100644 index 0000000..fddb54e --- /dev/null +++ b/services/core/java/com/android/server/NetworkTimeUpdateService.java @@ -0,0 +1,309 @@ +/* + * 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 com.android.server; + +import android.app.AlarmManager; +import android.app.PendingIntent; +import android.content.BroadcastReceiver; +import android.content.ContentResolver; +import android.content.Context; +import android.content.Intent; +import android.content.IntentFilter; +import android.database.ContentObserver; +import android.net.ConnectivityManager; +import android.net.NetworkInfo; +import android.os.Handler; +import android.os.HandlerThread; +import android.os.Looper; +import android.os.Message; +import android.os.SystemClock; +import android.provider.Settings; +import android.util.Log; +import android.util.NtpTrustedTime; +import android.util.TrustedTime; + +import com.android.internal.telephony.TelephonyIntents; + +/** + * Monitors the network time and updates the system time if it is out of sync + * and there hasn't been any NITZ update from the carrier recently. + * If looking up the network time fails for some reason, it tries a few times with a short + * interval and then resets to checking on longer intervals. + * <p> + * If the user enables AUTO_TIME, it will check immediately for the network time, if NITZ wasn't + * available. + * </p> + */ +public class NetworkTimeUpdateService { + + private static final String TAG = "NetworkTimeUpdateService"; + private static final boolean DBG = false; + + private static final int EVENT_AUTO_TIME_CHANGED = 1; + private static final int EVENT_POLL_NETWORK_TIME = 2; + private static final int EVENT_NETWORK_CONNECTED = 3; + + private static final String ACTION_POLL = + "com.android.server.NetworkTimeUpdateService.action.POLL"; + private static int POLL_REQUEST = 0; + + private static final long NOT_SET = -1; + private long mNitzTimeSetTime = NOT_SET; + // TODO: Have a way to look up the timezone we are in + private long mNitzZoneSetTime = NOT_SET; + + private Context mContext; + private TrustedTime mTime; + + // NTP lookup is done on this thread and handler + private Handler mHandler; + private AlarmManager mAlarmManager; + private PendingIntent mPendingPollIntent; + private SettingsObserver mSettingsObserver; + // The last time that we successfully fetched the NTP time. + private long mLastNtpFetchTime = NOT_SET; + + // Normal polling frequency + private final long mPollingIntervalMs; + // Try-again polling interval, in case the network request failed + private final long mPollingIntervalShorterMs; + // Number of times to try again + private final int mTryAgainTimesMax; + // If the time difference is greater than this threshold, then update the time. + private final int mTimeErrorThresholdMs; + // Keeps track of how many quick attempts were made to fetch NTP time. + // During bootup, the network may not have been up yet, or it's taking time for the + // connection to happen. + private int mTryAgainCounter; + + public NetworkTimeUpdateService(Context context) { + mContext = context; + mTime = NtpTrustedTime.getInstance(context); + mAlarmManager = (AlarmManager) mContext.getSystemService(Context.ALARM_SERVICE); + Intent pollIntent = new Intent(ACTION_POLL, null); + mPendingPollIntent = PendingIntent.getBroadcast(mContext, POLL_REQUEST, pollIntent, 0); + + mPollingIntervalMs = mContext.getResources().getInteger( + com.android.internal.R.integer.config_ntpPollingInterval); + mPollingIntervalShorterMs = mContext.getResources().getInteger( + com.android.internal.R.integer.config_ntpPollingIntervalShorter); + mTryAgainTimesMax = mContext.getResources().getInteger( + com.android.internal.R.integer.config_ntpRetry); + mTimeErrorThresholdMs = mContext.getResources().getInteger( + com.android.internal.R.integer.config_ntpThreshold); + } + + /** Initialize the receivers and initiate the first NTP request */ + public void systemRunning() { + registerForTelephonyIntents(); + registerForAlarms(); + registerForConnectivityIntents(); + + HandlerThread thread = new HandlerThread(TAG); + thread.start(); + mHandler = new MyHandler(thread.getLooper()); + // Check the network time on the new thread + mHandler.obtainMessage(EVENT_POLL_NETWORK_TIME).sendToTarget(); + + mSettingsObserver = new SettingsObserver(mHandler, EVENT_AUTO_TIME_CHANGED); + mSettingsObserver.observe(mContext); + } + + private void registerForTelephonyIntents() { + IntentFilter intentFilter = new IntentFilter(); + intentFilter.addAction(TelephonyIntents.ACTION_NETWORK_SET_TIME); + intentFilter.addAction(TelephonyIntents.ACTION_NETWORK_SET_TIMEZONE); + mContext.registerReceiver(mNitzReceiver, intentFilter); + } + + private void registerForAlarms() { + mContext.registerReceiver( + new BroadcastReceiver() { + @Override + public void onReceive(Context context, Intent intent) { + mHandler.obtainMessage(EVENT_POLL_NETWORK_TIME).sendToTarget(); + } + }, new IntentFilter(ACTION_POLL)); + } + + private void registerForConnectivityIntents() { + IntentFilter intentFilter = new IntentFilter(); + intentFilter.addAction(ConnectivityManager.CONNECTIVITY_ACTION); + mContext.registerReceiver(mConnectivityReceiver, intentFilter); + } + + private void onPollNetworkTime(int event) { + // If Automatic time is not set, don't bother. + if (!isAutomaticTimeRequested()) return; + + final long refTime = SystemClock.elapsedRealtime(); + // If NITZ time was received less than mPollingIntervalMs time ago, + // no need to sync to NTP. + if (mNitzTimeSetTime != NOT_SET && refTime - mNitzTimeSetTime < mPollingIntervalMs) { + resetAlarm(mPollingIntervalMs); + return; + } + final long currentTime = System.currentTimeMillis(); + if (DBG) Log.d(TAG, "System time = " + currentTime); + // Get the NTP time + if (mLastNtpFetchTime == NOT_SET || refTime >= mLastNtpFetchTime + mPollingIntervalMs + || event == EVENT_AUTO_TIME_CHANGED) { + if (DBG) Log.d(TAG, "Before Ntp fetch"); + + // force refresh NTP cache when outdated + if (mTime.getCacheAge() >= mPollingIntervalMs) { + mTime.forceRefresh(); + } + + // only update when NTP time is fresh + if (mTime.getCacheAge() < mPollingIntervalMs) { + final long ntp = mTime.currentTimeMillis(); + mTryAgainCounter = 0; + // If the clock is more than N seconds off or this is the first time it's been + // fetched since boot, set the current time. + if (Math.abs(ntp - currentTime) > mTimeErrorThresholdMs + || mLastNtpFetchTime == NOT_SET) { + // Set the system time + if (DBG && mLastNtpFetchTime == NOT_SET + && Math.abs(ntp - currentTime) <= mTimeErrorThresholdMs) { + Log.d(TAG, "For initial setup, rtc = " + currentTime); + } + if (DBG) Log.d(TAG, "Ntp time to be set = " + ntp); + // Make sure we don't overflow, since it's going to be converted to an int + if (ntp / 1000 < Integer.MAX_VALUE) { + SystemClock.setCurrentTimeMillis(ntp); + } + } else { + if (DBG) Log.d(TAG, "Ntp time is close enough = " + ntp); + } + mLastNtpFetchTime = SystemClock.elapsedRealtime(); + } else { + // Try again shortly + mTryAgainCounter++; + if (mTryAgainTimesMax < 0 || mTryAgainCounter <= mTryAgainTimesMax) { + resetAlarm(mPollingIntervalShorterMs); + } else { + // Try much later + mTryAgainCounter = 0; + resetAlarm(mPollingIntervalMs); + } + return; + } + } + resetAlarm(mPollingIntervalMs); + } + + /** + * Cancel old alarm and starts a new one for the specified interval. + * + * @param interval when to trigger the alarm, starting from now. + */ + private void resetAlarm(long interval) { + mAlarmManager.cancel(mPendingPollIntent); + long now = SystemClock.elapsedRealtime(); + long next = now + interval; + mAlarmManager.set(AlarmManager.ELAPSED_REALTIME, next, mPendingPollIntent); + } + + /** + * Checks if the user prefers to automatically set the time. + */ + private boolean isAutomaticTimeRequested() { + return Settings.Global.getInt( + mContext.getContentResolver(), Settings.Global.AUTO_TIME, 0) != 0; + } + + /** Receiver for Nitz time events */ + private BroadcastReceiver mNitzReceiver = new BroadcastReceiver() { + + @Override + public void onReceive(Context context, Intent intent) { + String action = intent.getAction(); + if (TelephonyIntents.ACTION_NETWORK_SET_TIME.equals(action)) { + mNitzTimeSetTime = SystemClock.elapsedRealtime(); + } else if (TelephonyIntents.ACTION_NETWORK_SET_TIMEZONE.equals(action)) { + mNitzZoneSetTime = SystemClock.elapsedRealtime(); + } + } + }; + + /** Receiver for ConnectivityManager events */ + private BroadcastReceiver mConnectivityReceiver = new BroadcastReceiver() { + + @Override + public void onReceive(Context context, Intent intent) { + String action = intent.getAction(); + if (ConnectivityManager.CONNECTIVITY_ACTION.equals(action)) { + // There is connectivity + final ConnectivityManager connManager = (ConnectivityManager) context + .getSystemService(Context.CONNECTIVITY_SERVICE); + final NetworkInfo netInfo = connManager.getActiveNetworkInfo(); + if (netInfo != null) { + // Verify that it's a WIFI connection + if (netInfo.getState() == NetworkInfo.State.CONNECTED && + (netInfo.getType() == ConnectivityManager.TYPE_WIFI || + netInfo.getType() == ConnectivityManager.TYPE_ETHERNET) ) { + mHandler.obtainMessage(EVENT_NETWORK_CONNECTED).sendToTarget(); + } + } + } + } + }; + + /** Handler to do the network accesses on */ + private class MyHandler extends Handler { + + public MyHandler(Looper l) { + super(l); + } + + @Override + public void handleMessage(Message msg) { + switch (msg.what) { + case EVENT_AUTO_TIME_CHANGED: + case EVENT_POLL_NETWORK_TIME: + case EVENT_NETWORK_CONNECTED: + onPollNetworkTime(msg.what); + break; + } + } + } + + /** Observer to watch for changes to the AUTO_TIME setting */ + private static class SettingsObserver extends ContentObserver { + + private int mMsg; + private Handler mHandler; + + SettingsObserver(Handler handler, int msg) { + super(handler); + mHandler = handler; + mMsg = msg; + } + + void observe(Context context) { + ContentResolver resolver = context.getContentResolver(); + resolver.registerContentObserver(Settings.Global.getUriFor(Settings.Global.AUTO_TIME), + false, this); + } + + @Override + public void onChange(boolean selfChange) { + mHandler.obtainMessage(mMsg).sendToTarget(); + } + } +} |