Make state transitions clearer in NitzStateMachine (d11c4273) · Commits · e / os / android_frameworks_opt_telephony

src/java/com/android/internal/telephony/NitzStateMachine.java

+165 −153

Original line number	Diff line number	Diff line
		@@ -135,19 +135,20 @@ public class NitzStateMachine {
		* are in. Keep the time zone information from the NITZ string in
		* mNitzData so we can fix the time zone once know the country.
		*/
		private boolean mNeedFixZoneAfterNitz = false;
		private boolean mNeedCountryCodeForNitz = false;

		private NitzData mNitzData;
		private boolean mGotCountryCode = false;
		private String mSavedTimeZoneId;

		/**
		* Boolean is {@code true} if {@link #setTimeZoneFromNitz(NitzData, long)} has been called and
		* Boolean is {@code true} if {@link #handleNitzReceived(TimeStampedValue)} has been called and
		* was able to determine a time zone (which may not ultimately have been used due to user
		* settings). Cleared by {@link #clearNitzTimeZoneDetectionSuccessful()},
		* The flag can be used when historic NITZ data may no longer be valid. {@code true} indicates
		* it's not reasonable to try to set the time zone using less reliable algorithms than
		* NITZ-based detection such as by just using network country code.
		* settings). Cleared by {@link #handleNetworkAvailable()} and
		* {@link #handleNetworkUnavailable()}. The flag can be used when historic NITZ data may no
		* longer be valid. {@code true} indicates it's not reasonable to try to set the time zone using
		* less reliable algorithms than NITZ-based detection such as by just using network country
		* code.
		*/
		private boolean mNitzTimeZoneDetectionSuccessful = false;

		@@ -186,27 +187,41 @@ public class NitzStateMachine {
		@Override
		public void onTimeDetectionChange(boolean enabled) {
		if (enabled) {
		revertToNitzTime();
		handleAutoTimeEnabled();
		}
		}

		@Override
		public void onTimeZoneDetectionChange(boolean enabled) {
		if (enabled) {
		revertToNitzTimeZone();
		handleAutoTimeZoneEnabled();
		}
		}
		});
		}

		/**
		* Called when the device's network country is known, allowing the time zone detection to be
		* substantially more precise.
		* Called when the network country is set on the Phone. Although set, the network country code
		* may be invalid.
		*
		* @param countryChanged true when the country code is known to have changed, false if it
		* probably hasn't
		*/
		public void fixTimeZone(String isoCountryCode) {
		// Capture the time zone property. This allows us to tell whether the device has a time zone
		// set. TimeZone.getDefault() returns a default zone (GMT) even when time zone is not
		// explicitly set making the system property a better indicator.
		public void handleNetworkCountryCodeSet(boolean countryChanged) {
		mGotCountryCode = true;

		String isoCountryCode = mDeviceState.getNetworkCountryIsoForPhone();
		if (!TextUtils.isEmpty(isoCountryCode)
		&& !mNitzTimeZoneDetectionSuccessful
		&& mTimeServiceHelper.isTimeZoneDetectionEnabled()) {
		updateTimeZoneByNetworkCountryCode(isoCountryCode);
		}

		if (countryChanged \|\| mNeedCountryCodeForNitz) {
		// Capture the time zone property. This allows us to tell whether the device has a time
		// zone set. TimeZone.getDefault() returns a default zone (GMT) even when time zone is
		// not explicitly set making the system property a better indicator of whether an
		// explicit time zone choice has been made.
		final boolean isTimeZoneSettingInitialized =
		mTimeServiceHelper.isTimeZoneSettingInitialized();
		if (DBG) {
		@@ -214,15 +229,16 @@ public class NitzStateMachine {
		+ " isTimeZoneSettingInitialized=" + isTimeZoneSettingInitialized
		+ " mNitzData=" + mNitzData
		+ " iso-cc='" + isoCountryCode
		+ "' countryUsesUtc=" + mTimeZoneLookupHelper.countryUsesUtc(isoCountryCode));
		+ "' countryUsesUtc="
		+ mTimeZoneLookupHelper.countryUsesUtc(isoCountryCode));
		}
		String zoneId;
		if ("".equals(isoCountryCode) && mNeedFixZoneAfterNitz) {
		if (TextUtils.isEmpty(isoCountryCode) && mNeedCountryCodeForNitz) {
		// Country code not found. This is likely a test network.
		// Get a TimeZone based only on the NITZ parameters (best guess).

		// mNeedFixZoneAfterNitz is only set to true when mNitzData is set so there's no need to
		// check mNitzData == null.
		// mNeedCountryCodeForNitz is only set to true when mNitzData is set so there's no
		// need to check mNitzData == null.
		zoneId = mTimeZoneLookupHelper.guessZoneIdByNitz(mNitzData);
		if (DBG) {
		Rlog.d(LOG_TAG, "fixTimeZone(): guessNitzTimeZone returned " + zoneId);
		@@ -231,21 +247,22 @@ public class NitzStateMachine {
		&& isTimeZoneSettingInitialized
		&& !mTimeZoneLookupHelper.countryUsesUtc(isoCountryCode)) {

		// This case means that (1) the device received no NITZ signal yet or received an NITZ
		// signal that looks bogus due to having a zero offset from UTC, (2) the device has a
		// time zone set explicitly, and (3) the iso tells us the country is NOT one that uses a
		// zero offset. This is interpreted as being NITZ incorrectly reporting a local time and
		// not a UTC time. The zone is left as the current device's zone setting, and the time
		// may be adjusted by assuming the current zone setting is correct.
		// This case means that (1) the device received no NITZ signal yet or received an
		// NITZ signal that looks bogus due to having a zero offset from UTC, (2) the device
		// has a time zone set explicitly, and (3) the iso tells us the country is NOT one
		// that uses a zero offset. This is interpreted as being NITZ incorrectly reporting
		// a local time and not a UTC time. The zone is left as the current device's zone
		// setting, and the time may be adjusted by assuming the current zone setting is
		// correct.
		TimeZone zone = TimeZone.getDefault();
		zoneId = zone.getID();

		// Note that mNeedFixZoneAfterNitz => (implies) { mNitzData != null }. Therefore, if
		// mNitzData == null, mNeedFixZoneAfterNitz cannot be true. The code in this section
		// therefore means that when mNitzData == null (and the country is one that doesn't use
		// a zero UTC offset) the device will retain the existing time zone setting and not try
		// to derive one from the isoCountryCode.
		if (mNeedFixZoneAfterNitz) {
		// Note that mNeedCountryCodeForNitz => (implies) { mNitzData != null }. Therefore,
		// if mNitzData == null, mNeedCountryCodeForNitz cannot be true. The code in this
		// section therefore means that when mNitzData == null (and the country is one that
		// doesn't use a zero UTC offset) the device will retain the existing time zone
		// setting and not try to derive one from the isoCountryCode.
		if (mNeedCountryCodeForNitz) {
		try {
		// Acquire the wakelock as we're reading the system clock here.
		mWakeLock.acquire();
		@@ -263,7 +280,8 @@ public class NitzStateMachine {
		} else {
		// Adjust the saved NITZ time to account for tzOffset.
		mSavedNitzTime = new TimeStampedValue<>(
		mSavedNitzTime.mValue - tzOffset, mSavedNitzTime.mElapsedRealtime);
		mSavedNitzTime.mValue - tzOffset,
		mSavedNitzTime.mElapsedRealtime);
		if (DBG) {
		Rlog.d(LOG_TAG, "fixTimeZone: adj mSavedTime=" + mSavedNitzTime);
		}
		@@ -282,7 +300,7 @@ public class NitzStateMachine {
		0 /* when /, 0 / offset /, false / dst */, isoCountryCode);
		if (DBG) {
		Rlog.d(LOG_TAG, "fixTimeZone: No cached NITZ data available, using only country"
		+ " code. zone=" + zoneId);
		+ " code. zoneId=" + zoneId);
		}
		} else {
		zoneId = mTimeZoneLookupHelper.guessZoneIdByNitzCountry(mNitzData, isoCountryCode);
		@@ -294,7 +312,7 @@ public class NitzStateMachine {
		+ " isTimeZoneSettingInitialized=" + isTimeZoneSettingInitialized
		+ " mNitzData=" + mNitzData
		+ " iso-cc=" + isoCountryCode
		+ " mNeedFixZoneAfterNitz=" + mNeedFixZoneAfterNitz
		+ " mNeedCountryCodeForNitz=" + mNeedCountryCodeForNitz
		+ " zoneId=" + zoneId;
		mTimeZoneLog.log(tmpLog);

		@@ -305,13 +323,38 @@ public class NitzStateMachine {
		} else {
		Rlog.d(LOG_TAG, "fixTimeZone: skip changing zone as getAutoTimeZone was false");
		}
		if (mNeedFixZoneAfterNitz) {
		if (mNeedCountryCodeForNitz) {
		saveNitzTimeZone(zoneId);
		}
		} else {
		Rlog.d(LOG_TAG, "fixTimeZone: zone == null, do nothing for zone");
		}
		mNeedFixZoneAfterNitz = false;
		mNeedCountryCodeForNitz = false;
		}
		}

		/**
		* Informs the {@link NitzStateMachine} that the network has become available.
		*/
		public void handleNetworkAvailable() {
		if (DBG) {
		Rlog.d(LOG_TAG, "handleNetworkAvailable: mNitzTimeZoneDetectionSuccessful="
		+ mNitzTimeZoneDetectionSuccessful
		+ ", Setting mNitzTimeZoneDetectionSuccessful=false");
		}
		mNitzTimeZoneDetectionSuccessful = false;
		}

		/**
		* Informs the {@link NitzStateMachine} that the network has become unavailable.
		*/
		public void handleNetworkUnavailable() {
		if (DBG) {
		Rlog.d(LOG_TAG, "handleNetworkUnavailable");
		}

		mGotCountryCode = false;
		mNitzTimeZoneDetectionSuccessful = false;
		}

		/**
		@@ -325,16 +368,14 @@ public class NitzStateMachine {
		/**
		* Handle a new NITZ signal being received.
		*/
		public void setTimeAndTimeZoneFromNitz(NitzData newNitzData, long nitzReceiveTime) {
		setTimeZoneFromNitz(newNitzData, nitzReceiveTime);

		TimeStampedValue<NitzData> nitzSignal =
		new TimeStampedValue<>(newNitzData, nitzReceiveTime);
		setTimeFromNitz(nitzSignal);
		public void handleNitzReceived(TimeStampedValue<NitzData> nitzSignal) {
		handleTimeZoneFromNitz(nitzSignal);
		handleTimeFromNitz(nitzSignal);
		}

		private void setTimeZoneFromNitz(NitzData newNitzData, long nitzReceiveTime) {
		private void handleTimeZoneFromNitz(TimeStampedValue<NitzData> nitzSignal) {
		try {
		NitzData newNitzData = nitzSignal.mValue;
		String iso = mDeviceState.getNetworkCountryIsoForPhone();
		String zoneId;
		if (newNitzData.getEmulatorHostTimeZone() != null) {
		@@ -342,7 +383,7 @@ public class NitzStateMachine {
		} else {
		if (!mGotCountryCode) {
		zoneId = null;
		} else if (iso != null && iso.length() > 0) {
		} else if (!TextUtils.isEmpty(iso)) {
		zoneId = mTimeZoneLookupHelper.guessZoneIdByNitzCountry(newNitzData, iso);
		} else {
		// We don't have a valid iso country code. This is
		@@ -373,15 +414,14 @@ public class NitzStateMachine {
		// We got the time before the country or the zone has changed
		// so we don't know how to identify the DST rules yet. Save
		// the information and hope to fix it up later.
		mNeedFixZoneAfterNitz = true;
		mNeedCountryCodeForNitz = true;
		mNitzData = newNitzData;
		}

		String tmpLog = "NITZ: newNitzData=" + newNitzData
		+ " nitzReceiveTime=" + nitzReceiveTime
		String tmpLog = "NITZ: nitzTimeSignal=" + nitzSignal
		+ " zoneId=" + zoneId
		+ " iso=" + iso + " mGotCountryCode=" + mGotCountryCode
		+ " mNeedFixZoneAfterNitz=" + mNeedFixZoneAfterNitz
		+ " mNeedCountryCodeForNitz=" + mNeedCountryCodeForNitz
		+ " isTimeZoneDetectionEnabled()="
		+ mTimeServiceHelper.isTimeZoneDetectionEnabled();
		if (DBG) {
		@@ -397,11 +437,11 @@ public class NitzStateMachine {
		saveNitzTimeZone(zoneId);
		}
		} catch (RuntimeException ex) {
		Rlog.e(LOG_TAG, "NITZ: Processing NITZ data " + newNitzData + " ex=" + ex);
		Rlog.e(LOG_TAG, "NITZ: Processing NITZ data " + nitzSignal + " ex=" + ex);
		}
		}

		private void setTimeFromNitz(TimeStampedValue<NitzData> nitzTimeSignal) {
		private void handleTimeFromNitz(TimeStampedValue<NitzData> nitzTimeSignal) {
		try {
		boolean ignoreNitz = mDeviceState.getIgnoreNitz();
		if (ignoreNitz) {
		@@ -512,7 +552,7 @@ public class NitzStateMachine {
		TelephonyMetrics.getInstance().writeNITZEvent(mPhone.getPhoneId(), time);
		}

		private void revertToNitzTime() {
		private void handleAutoTimeEnabled() {
		if (DBG) {
		Rlog.d(LOG_TAG, "Reverting to NITZ Time: mSavedTime=" + mSavedNitzTime);
		}
		@@ -533,7 +573,7 @@ public class NitzStateMachine {
		}
		}

		private void revertToNitzTimeZone() {
		private void handleAutoTimeZoneEnabled() {
		String tmpLog = "Reverting to NITZ TimeZone: tz=" + mSavedTimeZoneId;
		if (DBG) {
		Rlog.d(LOG_TAG, tmpLog);
		@@ -557,7 +597,7 @@ public class NitzStateMachine {
		pw.println(" mSavedTime=" + mSavedNitzTime);

		// Time Zone Detection State
		pw.println(" mNeedFixZoneAfterNitz=" + mNeedFixZoneAfterNitz);
		pw.println(" mNeedCountryCodeForNitz=" + mNeedCountryCodeForNitz);
		pw.println(" mNitzData=" + mNitzData);
		pw.println(" mGotCountryCode=" + mGotCountryCode);
		pw.println(" mSavedTimeZone=" + mSavedTimeZoneId);
		@@ -589,7 +629,7 @@ public class NitzStateMachine {
		*
		* @param iso Country code from network MCC
		*/
		public void updateTimeZoneByNetworkCountryCode(String iso) {
		private void updateTimeZoneByNetworkCountryCode(String iso) {
		String zoneId = mTimeZoneLookupHelper.guessZoneIdByCountry(
		iso, mDeviceState.currentTimeMillis());
		if (zoneId != null) {
		@@ -610,13 +650,6 @@ public class NitzStateMachine {
		}
		}

		/**
		* Clear the mNitzTimeZoneDetectionSuccessful flag.
		*/
		public void clearNitzTimeZoneDetectionSuccessful() {
		mNitzTimeZoneDetectionSuccessful = false;
		}

		/**
		* Get the mNitzTimeZoneDetectionSuccessful flag value.
		*/
		@@ -624,21 +657,6 @@ public class NitzStateMachine {
		return mNitzTimeZoneDetectionSuccessful;
		}

		/**
		* Sets the mGotCountryCode flag to the specified value.
		*/
		public void setNetworkCountryIsoAvailable(boolean gotCountryCode) {
		mGotCountryCode = gotCountryCode;
		}

		/**
		* Returns true if !mNitzTimeZoneDetectionSuccessful and automatic time zone detection is
		* enabled.
		*/
		public boolean shouldUpdateTimeZoneUsingCountryCode() {
		return !mNitzTimeZoneDetectionSuccessful && mTimeServiceHelper.isTimeZoneDetectionEnabled();
		}

		/**
		* Returns the last NITZ data that was cached.
		*/
		@@ -654,10 +672,4 @@ public class NitzStateMachine {
		return mSavedTimeZoneId;
		}

		/**
		* Returns the mNeedFixZoneAfterNitz flag value.
		*/
		public boolean fixTimeZoneCallNeeded() {
		return mNeedFixZoneAfterNitz;
		}
		}

src/java/com/android/internal/telephony/ServiceStateTracker.java

+56 −74

File changed.

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tests/telephonytests/src/com/android/internal/telephony/NitzStateMachineTest.java

+38 −46

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tests/telephonytests/src/com/android/internal/telephony/ServiceStateTrackerTest.java

+12 −3

Original line number	Diff line number	Diff line
		@@ -45,6 +45,7 @@ import android.os.Message;
		import android.os.Parcel;
		import android.os.PersistableBundle;
		import android.os.Process;
		import android.os.SystemClock;
		import android.os.UserHandle;
		import android.os.WorkSource;
		import android.support.test.filters.FlakyTest;
		@@ -63,6 +64,7 @@ import com.android.internal.telephony.cdma.CdmaSubscriptionSourceManager;
		import com.android.internal.telephony.dataconnection.DcTracker;
		import com.android.internal.telephony.test.SimulatedCommands;
		import com.android.internal.telephony.uicc.IccCardApplicationStatus;
		import com.android.internal.telephony.util.TimeStampedValue;

		import org.junit.After;
		import org.junit.Before;
		@@ -1146,8 +1148,7 @@ public class ServiceStateTrackerTest extends TelephonyTest {
		// Mock sending incorrect nitz str from RIL
		mSimulatedCommands.triggerNITZupdate("38/06/20,00:00:00+0");
		waitForMs(200);
		verify(mNitzStateMachine, times(0))
		.setTimeAndTimeZoneFromNitz(any(), anyLong());
		verify(mNitzStateMachine, times(0)).handleNitzReceived(any());
		}
		{
		// Mock sending correct nitz str from RIL
		@@ -1155,8 +1156,16 @@ public class ServiceStateTrackerTest extends TelephonyTest {
		NitzData expectedNitzData = NitzData.parse(nitzStr);
		mSimulatedCommands.triggerNITZupdate(nitzStr);
		waitForMs(200);

		ArgumentCaptor<TimeStampedValue<NitzData>> argumentsCaptor =
		ArgumentCaptor.forClass(TimeStampedValue.class);
		verify(mNitzStateMachine, times(1))
		.setTimeAndTimeZoneFromNitz(eq(expectedNitzData), anyLong());
		.handleNitzReceived(argumentsCaptor.capture());

		// Confirm the argument was what we expected.
		TimeStampedValue<NitzData> actualNitzSignal = argumentsCaptor.getValue();
		assertEquals(expectedNitzData, actualNitzSignal.mValue);
		assertTrue(actualNitzSignal.mElapsedRealtime <= SystemClock.elapsedRealtime());
		}
		}
		}