Simple pass-through TimeDetectorService

This is sufficient to wire up time detection from telephony
to the new service without breaking time detection.

This cherry-pick contains a small change: to use
SystemClock.elapsedRealtime() instead of the newer
SystemClock.elapsedRealtimeClock() with Clock.millis().

Bug: 78217059
Test: atest FrameworksServicesTests:com.android.server.timedetector
Test: atest FrameworksCoreTests:android.util.TimestampedValueTest
Merged-In: Id7175878dc22e5272c31f3e478af4b0e4183b62b
Change-Id: Id7175878dc22e5272c31f3e478af4b0e4183b62b
(cherry picked from commit 24836bfb1564b1f98c322108a924965a8dbbee4f)
diff --git a/services/core/java/com/android/server/timedetector/SimpleTimeDetectorStrategy.java b/services/core/java/com/android/server/timedetector/SimpleTimeDetectorStrategy.java
new file mode 100644
index 0000000..e5207cb
--- /dev/null
+++ b/services/core/java/com/android/server/timedetector/SimpleTimeDetectorStrategy.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2018 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.timedetector;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.app.AlarmManager;
+import android.app.timedetector.TimeSignal;
+import android.util.Slog;
+
+import java.io.FileDescriptor;
+import java.io.PrintWriter;
+
+/**
+ * A placeholder implementation of TimeDetectorStrategy that passes NITZ suggestions immediately
+ * to {@link AlarmManager}.
+ */
+public final class SimpleTimeDetectorStrategy implements TimeDetectorStrategy {
+
+    private final static String TAG = "timedetector.SimpleTimeDetectorStrategy";
+
+    private Callback mHelper;
+
+    @Override
+    public void initialize(@NonNull Callback callback) {
+        mHelper = callback;
+    }
+
+    @Override
+    public void suggestTime(@NonNull TimeSignal timeSignal) {
+        if (!TimeSignal.SOURCE_ID_NITZ.equals(timeSignal.getSourceId())) {
+            Slog.w(TAG, "Ignoring signal from unknown source: " + timeSignal);
+            return;
+        }
+
+        mHelper.setTime(timeSignal.getUtcTime());
+    }
+
+    @Override
+    public void dump(@NonNull FileDescriptor fd, @NonNull PrintWriter pw, @Nullable String[] args) {
+        // No state to dump.
+    }
+}
diff --git a/services/core/java/com/android/server/timedetector/TimeDetectorService.java b/services/core/java/com/android/server/timedetector/TimeDetectorService.java
index 0b63e29..efd49b5 100644
--- a/services/core/java/com/android/server/timedetector/TimeDetectorService.java
+++ b/services/core/java/com/android/server/timedetector/TimeDetectorService.java
@@ -16,15 +16,19 @@
 
 package com.android.server.timedetector;
 
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.app.timedetector.ITimeDetectorService;
+import android.app.timedetector.TimeSignal;
+import android.content.Context;
+
+import com.android.internal.annotations.VisibleForTesting;
 import com.android.internal.util.DumpUtils;
 import com.android.server.SystemService;
 
-import android.app.timedetector.ITimeDetectorService;
-import android.content.Context;
-import android.util.Slog;
-
 import java.io.FileDescriptor;
 import java.io.PrintWriter;
+import java.util.Objects;
 
 public final class TimeDetectorService extends ITimeDetectorService.Stub {
 
@@ -47,26 +51,36 @@
     }
 
     private final Context mContext;
+    private final TimeDetectorStrategy mTimeDetectorStrategy;
 
     private static TimeDetectorService create(Context context) {
-        return new TimeDetectorService(context);
+        TimeDetectorStrategy timeDetector = new SimpleTimeDetectorStrategy();
+        timeDetector.initialize(new TimeDetectorStrategyCallbackImpl(context));
+        return new TimeDetectorService(context, timeDetector);
     }
 
-    public TimeDetectorService(Context context) {
-        mContext = context;
+    @VisibleForTesting
+    public TimeDetectorService(@NonNull Context context,
+            @NonNull TimeDetectorStrategy timeDetectorStrategy) {
+        mContext = Objects.requireNonNull(context);
+        mTimeDetectorStrategy = Objects.requireNonNull(timeDetectorStrategy);
     }
 
     @Override
-    public void stubbedCall() {
-        // Empty call for initial tests.
-        Slog.d(TAG, "stubbedCall() called");
-        // TODO(nfuller): Remove when there are real methods.
+    public void suggestTime(@NonNull TimeSignal timeSignal) {
+        enforceSetTimePermission();
+        mTimeDetectorStrategy.suggestTime(timeSignal);
     }
 
     @Override
-    protected void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
+    protected void dump(@NonNull FileDescriptor fd, @NonNull PrintWriter pw,
+            @Nullable String[] args) {
         if (!DumpUtils.checkDumpPermission(mContext, TAG, pw)) return;
 
-        // TODO(nfuller): Implement when there is state.
+        mTimeDetectorStrategy.dump(fd, pw, args);
+    }
+
+    private void enforceSetTimePermission() {
+        mContext.enforceCallingPermission(android.Manifest.permission.SET_TIME, "set time");
     }
 }
\ No newline at end of file
diff --git a/services/core/java/com/android/server/timedetector/TimeDetectorStrategy.java b/services/core/java/com/android/server/timedetector/TimeDetectorStrategy.java
new file mode 100644
index 0000000..5cb2eed
--- /dev/null
+++ b/services/core/java/com/android/server/timedetector/TimeDetectorStrategy.java
@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) 2018 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.timedetector;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.app.timedetector.TimeSignal;
+import android.util.TimestampedValue;
+
+import java.io.FileDescriptor;
+import java.io.PrintWriter;
+
+/**
+ * The interface for classes that implement the time detection algorithm used by the
+ * TimeDetectorService.
+ *
+ * @hide
+ */
+public interface TimeDetectorStrategy {
+
+    interface Callback {
+        void setTime(TimestampedValue<Long> time);
+    }
+
+    void initialize(@NonNull Callback callback);
+    void suggestTime(@NonNull TimeSignal timeSignal);
+    void dump(@NonNull FileDescriptor fd, @NonNull PrintWriter pw, @Nullable String[] args);
+
+    // Utility methods below are to be moved to a better home when one becomes more obvious.
+
+    /**
+     * Adjusts the supplied time value by applying the difference between the reference time
+     * supplied and the reference time associated with the time.
+     */
+    static long getTimeAt(@NonNull TimestampedValue<Long> timeValue, long referenceClockMillisNow) {
+        return (referenceClockMillisNow - timeValue.getReferenceTimeMillis())
+                + timeValue.getValue();
+    }
+}
diff --git a/services/core/java/com/android/server/timedetector/TimeDetectorStrategyCallbackImpl.java b/services/core/java/com/android/server/timedetector/TimeDetectorStrategyCallbackImpl.java
new file mode 100644
index 0000000..568d73a
--- /dev/null
+++ b/services/core/java/com/android/server/timedetector/TimeDetectorStrategyCallbackImpl.java
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2018 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.timedetector;
+
+import android.annotation.NonNull;
+import android.app.AlarmManager;
+import android.content.Context;
+import android.os.PowerManager;
+import android.os.SystemClock;
+import android.util.Slog;
+import android.util.TimestampedValue;
+
+/**
+ * The real implementation of {@link TimeDetectorStrategy.Callback} used on device.
+ */
+public class TimeDetectorStrategyCallbackImpl implements TimeDetectorStrategy.Callback {
+
+    private final static String TAG = "timedetector.TimeDetectorStrategyCallbackImpl";
+
+    @NonNull private PowerManager.WakeLock mWakeLock;
+    @NonNull private AlarmManager mAlarmManager;
+
+    public TimeDetectorStrategyCallbackImpl(Context context) {
+        PowerManager powerManager = context.getSystemService(PowerManager.class);
+
+        mWakeLock = powerManager.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, TAG);
+
+        mAlarmManager = context.getSystemService(AlarmManager.class);
+    }
+
+    @Override
+    public void setTime(TimestampedValue<Long> time) {
+        mWakeLock.acquire();
+        try {
+            long elapsedRealtimeMillis = SystemClock.elapsedRealtime();
+            long currentTimeMillis = TimeDetectorStrategy.getTimeAt(time, elapsedRealtimeMillis);
+            Slog.d(TAG, "Setting system clock using time=" + time
+                    + ", elapsedRealtimeMillis=" + elapsedRealtimeMillis);
+            mAlarmManager.setTime(currentTimeMillis);
+        } finally {
+            mWakeLock.release();
+        }
+    }
+}
diff --git a/services/tests/servicestests/src/com/android/server/timedetector/SimpleTimeZoneDetectorStrategyTest.java b/services/tests/servicestests/src/com/android/server/timedetector/SimpleTimeZoneDetectorStrategyTest.java
new file mode 100644
index 0000000..e4b3b13
--- /dev/null
+++ b/services/tests/servicestests/src/com/android/server/timedetector/SimpleTimeZoneDetectorStrategyTest.java
@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2018 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.timedetector;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+
+import android.app.timedetector.TimeSignal;
+import android.support.test.runner.AndroidJUnit4;
+import android.util.TimestampedValue;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+@RunWith(AndroidJUnit4.class)
+public class SimpleTimeZoneDetectorStrategyTest {
+
+    private TimeDetectorStrategy.Callback mMockCallback;
+
+    private SimpleTimeDetectorStrategy mSimpleTimeZoneDetectorStrategy;
+
+    @Before
+    public void setUp() {
+        mMockCallback = mock(TimeDetectorStrategy.Callback.class);
+        mSimpleTimeZoneDetectorStrategy = new SimpleTimeDetectorStrategy();
+        mSimpleTimeZoneDetectorStrategy.initialize(mMockCallback);
+    }
+
+    @Test
+    public void testSuggestTime_nitz() {
+        TimestampedValue<Long> utcTime = createUtcTime();
+        TimeSignal timeSignal = new TimeSignal(TimeSignal.SOURCE_ID_NITZ, utcTime);
+
+        mSimpleTimeZoneDetectorStrategy.suggestTime(timeSignal);
+
+        verify(mMockCallback).setTime(utcTime);
+    }
+
+    @Test
+    public void testSuggestTime_unknownSource() {
+        TimestampedValue<Long> utcTime = createUtcTime();
+        TimeSignal timeSignal = new TimeSignal("unknown", utcTime);
+        mSimpleTimeZoneDetectorStrategy.suggestTime(timeSignal);
+
+        verify(mMockCallback, never()).setTime(any());
+    }
+
+    private static TimestampedValue<Long> createUtcTime() {
+        return new TimestampedValue<>(321L, 123456L);
+    }
+}
diff --git a/services/tests/servicestests/src/com/android/server/timedetector/TimeDetectorServiceTest.java b/services/tests/servicestests/src/com/android/server/timedetector/TimeDetectorServiceTest.java
index dc17eeb..22dea92 100644
--- a/services/tests/servicestests/src/com/android/server/timedetector/TimeDetectorServiceTest.java
+++ b/services/tests/servicestests/src/com/android/server/timedetector/TimeDetectorServiceTest.java
@@ -16,31 +16,73 @@
 
 package com.android.server.timedetector;
 
-import android.content.Context;
-import android.support.test.InstrumentationRegistry;
-import android.support.test.runner.AndroidJUnit4;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.doNothing;
+import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
 
+import android.app.timedetector.TimeSignal;
+import android.content.Context;
+import android.support.test.runner.AndroidJUnit4;
+import android.util.TimestampedValue;
+
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
-/**
- * Unit tests for the {@link TimeDetectorService}.
- */
 @RunWith(AndroidJUnit4.class)
 public class TimeDetectorServiceTest {
 
     private TimeDetectorService mTimeDetectorService;
 
+    private Context mMockContext;
+    private TimeDetectorStrategy mMockTimeDetectorStrategy;
+
     @Before
     public void setUp() {
-        final Context context = InstrumentationRegistry.getContext();
-        mTimeDetectorService = new TimeDetectorService(context);
+        mMockContext = mock(Context.class);
+        mMockTimeDetectorStrategy = mock(TimeDetectorStrategy.class);
+        mTimeDetectorService = new TimeDetectorService(mMockContext, mMockTimeDetectorStrategy);
+    }
+
+    @After
+    public void tearDown() {
+        verifyNoMoreInteractions(mMockContext, mMockTimeDetectorStrategy);
+    }
+
+    @Test(expected=SecurityException.class)
+    public void testStubbedCall_withoutPermission() {
+        doThrow(new SecurityException("Mock"))
+                .when(mMockContext).enforceCallingPermission(anyString(), any());
+        TimeSignal timeSignal = createNitzTimeSignal();
+
+        try {
+            mTimeDetectorService.suggestTime(timeSignal);
+        } finally {
+            verify(mMockContext).enforceCallingPermission(
+                    eq(android.Manifest.permission.SET_TIME), anyString());
+        }
     }
 
     @Test
-    public void testStubbedCall() {
-        mTimeDetectorService.stubbedCall();
+    public void testSuggestTime() {
+        doNothing().when(mMockContext).enforceCallingPermission(anyString(), any());
+
+        TimeSignal timeSignal = createNitzTimeSignal();
+        mTimeDetectorService.suggestTime(timeSignal);
+
+        verify(mMockContext)
+                .enforceCallingPermission(eq(android.Manifest.permission.SET_TIME), anyString());
+        verify(mMockTimeDetectorStrategy).suggestTime(timeSignal);
     }
 
+    private static TimeSignal createNitzTimeSignal() {
+        TimestampedValue<Long> timeValue = new TimestampedValue<>(100L, 1_000_000L);
+        return new TimeSignal(TimeSignal.SOURCE_ID_NITZ, timeValue);
+    }
 }
diff --git a/services/tests/servicestests/src/com/android/server/timedetector/TimeDetectorStrategyTest.java b/services/tests/servicestests/src/com/android/server/timedetector/TimeDetectorStrategyTest.java
new file mode 100644
index 0000000..301ded4
--- /dev/null
+++ b/services/tests/servicestests/src/com/android/server/timedetector/TimeDetectorStrategyTest.java
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2018 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.timedetector;
+
+import static org.junit.Assert.assertEquals;
+
+import android.support.test.runner.AndroidJUnit4;
+import android.util.TimestampedValue;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+@RunWith(AndroidJUnit4.class)
+public class TimeDetectorStrategyTest {
+
+    @Test
+    public void testGetTimeAt() {
+        long timeMillis = 1000L;
+        int referenceTimeMillis = 100;
+        TimestampedValue<Long> timestampedValue =
+                new TimestampedValue<>(referenceTimeMillis, timeMillis);
+        // Reference time is after the timestamp.
+        assertEquals(
+                timeMillis + (125 - referenceTimeMillis),
+                TimeDetectorStrategy.getTimeAt(timestampedValue, 125));
+
+        // Reference time is before the timestamp.
+        assertEquals(
+                timeMillis + (75 - referenceTimeMillis),
+                TimeDetectorStrategy.getTimeAt(timestampedValue, 75));
+    }
+}