Enforcing a minimum window on inexact alarms (2d736276) · Commits · e / os / android_frameworks_base

apex/jobscheduler/framework/java/android/app/AlarmManager.java

+31 −4

Original line number	Original line	Diff line number	Diff line
	@@ -208,10 +208,10 @@ public class AlarmManager {
	public static final int FLAG_PRIORITIZE = 1 << 6;		public static final int FLAG_PRIORITIZE = 1 << 6;

	/**		/**
	* For apps targeting {@link Build.VERSION_CODES#S} or above, APIs		* For apps targeting {@link Build.VERSION_CODES#S} or above, any APIs setting exact alarms,
	* {@link #setExactAndAllowWhileIdle(int, long, PendingIntent)} and		* e.g. {@link #setExact(int, long, PendingIntent)},
	* {@link #setAlarmClock(AlarmClockInfo, PendingIntent)} will require holding a new		* {@link #setAlarmClock(AlarmClockInfo, PendingIntent)} and others will require holding a new
	* permission {@link android.Manifest.permission#SCHEDULE_EXACT_ALARM}		* permission {@link Manifest.permission#SCHEDULE_EXACT_ALARM}
	*		*
	* @hide		* @hide
	*/		*/
	@@ -219,6 +219,21 @@ public class AlarmManager {
	@EnabledSince(targetSdkVersion = Build.VERSION_CODES.S)		@EnabledSince(targetSdkVersion = Build.VERSION_CODES.S)
	public static final long REQUIRE_EXACT_ALARM_PERMISSION = 171306433L;		public static final long REQUIRE_EXACT_ALARM_PERMISSION = 171306433L;

			/**
			* For apps targeting {@link Build.VERSION_CODES#S} or above, all inexact alarms will require
			* to have a minimum window size, expected to be on the order of a few minutes.
			*
			* Practically, any alarms requiring smaller windows are the same as exact alarms and should use
			* the corresponding APIs provided, like {@link #setExact(int, long, PendingIntent)}, et al.
			*
			* Inexact alarm with shorter windows specified will have their windows elongated by the system.
			*
			* @hide
			*/
			@ChangeId
			@EnabledSince(targetSdkVersion = Build.VERSION_CODES.S)
			public static final long ENFORCE_MINIMUM_WINDOW_ON_INEXACT_ALARMS = 185199076L;

	@UnsupportedAppUsage		@UnsupportedAppUsage
	private final IAlarmManager mService;		private final IAlarmManager mService;
	private final Context mContext;		private final Context mContext;
	@@ -483,6 +498,11 @@ public class AlarmManager {
	* modest timeliness requirements for its alarms.		* modest timeliness requirements for its alarms.
	*		*
	* <p>		* <p>
			* Note: Starting with API {@link Build.VERSION_CODES#S}, the system will ensure that the window
			* specified is at least a few minutes, as smaller windows are considered practically exact
			* and should use the other APIs provided for exact alarms.
			*
			* <p>
	* This method can also be used to achieve strict ordering guarantees among		* This method can also be used to achieve strict ordering guarantees among
	* multiple alarms by ensuring that the windows requested for each alarm do		* multiple alarms by ensuring that the windows requested for each alarm do
	* not intersect.		* not intersect.
	@@ -532,6 +552,13 @@ public class AlarmManager {
	* The OnAlarmListener {@link OnAlarmListener#onAlarm() onAlarm()} method will be		* The OnAlarmListener {@link OnAlarmListener#onAlarm() onAlarm()} method will be
	* invoked via the specified target Handler, or on the application's main looper		* invoked via the specified target Handler, or on the application's main looper
	* if {@code null} is passed as the {@code targetHandler} parameter.		* if {@code null} is passed as the {@code targetHandler} parameter.
			*
			* <p>
			* Note: Starting with API {@link Build.VERSION_CODES#S}, the system will ensure that the window
			* specified is at least a few minutes, as smaller windows are considered practically exact
			* and should use the other APIs provided for exact alarms.
			*
			* @see #setWindow(int, long, long, PendingIntent)
	*/		*/
	public void setWindow(@AlarmType int type, long windowStartMillis, long windowLengthMillis,		public void setWindow(@AlarmType int type, long windowStartMillis, long windowLengthMillis,
	String tag, OnAlarmListener listener, Handler targetHandler) {		String tag, OnAlarmListener listener, Handler targetHandler) {

apex/jobscheduler/service/java/com/android/server/alarm/AlarmManagerService.java

+17 −7

Original line number	Original line	Diff line number	Diff line
	@@ -452,7 +452,8 @@ public class AlarmManagerService extends SystemService {
	private static final long DEFAULT_MIN_FUTURITY = 5 * 1000;		private static final long DEFAULT_MIN_FUTURITY = 5 * 1000;
	private static final long DEFAULT_MIN_INTERVAL = 60 * 1000;		private static final long DEFAULT_MIN_INTERVAL = 60 * 1000;
	private static final long DEFAULT_MAX_INTERVAL = 365 * INTERVAL_DAY;		private static final long DEFAULT_MAX_INTERVAL = 365 * INTERVAL_DAY;
	private static final long DEFAULT_MIN_WINDOW = 10_000;		// TODO (b/185199076): Tune based on breakage reports.
			private static final long DEFAULT_MIN_WINDOW = 30 * 60 * 1000;
	private static final long DEFAULT_ALLOW_WHILE_IDLE_WHITELIST_DURATION = 10 * 1000;		private static final long DEFAULT_ALLOW_WHILE_IDLE_WHITELIST_DURATION = 10 * 1000;
	private static final long DEFAULT_LISTENER_TIMEOUT = 5 * 1000;		private static final long DEFAULT_LISTENER_TIMEOUT = 5 * 1000;
	private static final int DEFAULT_MAX_ALARMS_PER_UID = 500;		private static final int DEFAULT_MAX_ALARMS_PER_UID = 500;
	@@ -1688,12 +1689,22 @@ public class AlarmManagerService extends SystemService {
	windowLength = AlarmManager.WINDOW_EXACT;		windowLength = AlarmManager.WINDOW_EXACT;
	}		}

	// Sanity check the window length. This will catch people mistakenly		// Snap the window to reasonable limits.
	// trying to pass an end-of-window timestamp rather than a duration.		if (windowLength > INTERVAL_DAY) {
	if (windowLength > AlarmManager.INTERVAL_HALF_DAY) {
	Slog.w(TAG, "Window length " + windowLength		Slog.w(TAG, "Window length " + windowLength
	+ "ms suspiciously long; limiting to 1 hour");		+ "ms suspiciously long; limiting to 1 day");
	windowLength = AlarmManager.INTERVAL_HOUR;		windowLength = INTERVAL_DAY;
			} else if (windowLength > 0 && windowLength < mConstants.MIN_WINDOW) {
			if (CompatChanges.isChangeEnabled(AlarmManager.ENFORCE_MINIMUM_WINDOW_ON_INEXACT_ALARMS,
			callingPackage, UserHandle.getUserHandleForUid(callingUid))) {
			Slog.w(TAG, "Window length " + windowLength + "ms too short; expanding to "
			+ mConstants.MIN_WINDOW + "ms.");
			windowLength = mConstants.MIN_WINDOW;
			} else {
			// TODO (b/185199076): Remove log once we have some data about what apps will break
			Slog.wtf(TAG, "Short window " + windowLength + "ms specified by "
			+ callingPackage);
			}
	}		}

	// Sanity check the recurrence interval. This will catch people who supply		// Sanity check the recurrence interval. This will catch people who supply
	@@ -1737,7 +1748,6 @@ public class AlarmManagerService extends SystemService {
	// Fix this window in place, so that as time approaches we don't collapse it.		// Fix this window in place, so that as time approaches we don't collapse it.
	windowLength = maxElapsed - triggerElapsed;		windowLength = maxElapsed - triggerElapsed;
	} else {		} else {
	windowLength = Math.max(windowLength, mConstants.MIN_WINDOW);
	maxElapsed = triggerElapsed + windowLength;		maxElapsed = triggerElapsed + windowLength;
	}		}
	synchronized (mLock) {		synchronized (mLock) {

services/tests/mockingservicestests/src/com/android/server/alarm/AlarmManagerServiceTest.java

+25 −1

Original line number	Original line	Diff line number	Diff line
	@@ -2223,7 +2223,11 @@ public class AlarmManagerServiceTest {
	}		}

	@Test		@Test
	public void minWindow() {		public void minWindowChangeEnabled() {
			doReturn(true).when(
			() -> CompatChanges.isChangeEnabled(
			eq(AlarmManager.ENFORCE_MINIMUM_WINDOW_ON_INEXACT_ALARMS),
			anyString(), any(UserHandle.class)));
	final long minWindow = 73;		final long minWindow = 73;
	setDeviceConfigLong(KEY_MIN_WINDOW, minWindow);		setDeviceConfigLong(KEY_MIN_WINDOW, minWindow);

	@@ -2238,6 +2242,26 @@ public class AlarmManagerServiceTest {
	}		}
	}		}

			@Test
			public void minWindowChangeDisabled() {
			doReturn(false).when(
			() -> CompatChanges.isChangeEnabled(
			eq(AlarmManager.ENFORCE_MINIMUM_WINDOW_ON_INEXACT_ALARMS),
			anyString(), any(UserHandle.class)));
			final long minWindow = 73;
			setDeviceConfigLong(KEY_MIN_WINDOW, minWindow);

			// 0 is WINDOW_EXACT and < 0 is WINDOW_HEURISTIC.
			for (int window = 1; window <= minWindow; window++) {
			final PendingIntent pi = getNewMockPendingIntent();
			setTestAlarm(ELAPSED_REALTIME, 0, window, pi, 0, 0, TEST_CALLING_UID, null);

			assertEquals(1, mService.mAlarmStore.size());
			final Alarm a = mService.mAlarmStore.remove(unused -> true).get(0);
			assertEquals(window, a.windowLength);
			}
			}

	@Test		@Test
	public void denyListPackagesAdded() {		public void denyListPackagesAdded() {
	mService.mConstants.EXACT_ALARM_DENY_LIST = new ArraySet<>(new String[]{"p1", "p2", "p3"});		mService.mConstants.EXACT_ALARM_DENY_LIST = new ArraySet<>(new String[]{"p1", "p2", "p3"});