Refactor request lifecycle logic into OverrideRequestController. (a5ab448f) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/devicestate/DeviceStateManagerService.java

+204 −286

File changed.

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services/core/java/com/android/server/devicestate/OverrideRequest.java

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+58 −0

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		/*
		* Copyright (C) 2021 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.devicestate;

		import android.hardware.devicestate.DeviceStateRequest;
		import android.os.IBinder;

		/**
		* A request to override the state managed by {@link DeviceStateManagerService}.
		*
		* @see OverrideRequestController
		*/
		final class OverrideRequest {
		private final IBinder mToken;
		private final int mPid;
		private final int mRequestedState;
		@DeviceStateRequest.RequestFlags
		private final int mFlags;

		OverrideRequest(IBinder token, int pid, int requestedState,
		@DeviceStateRequest.RequestFlags int flags) {
		mToken = token;
		mPid = pid;
		mRequestedState = requestedState;
		mFlags = flags;
		}

		IBinder getToken() {
		return mToken;
		}

		int getPid() {
		return mPid;
		}

		int getRequestedState() {
		return mRequestedState;
		}

		@DeviceStateRequest.RequestFlags
		int getFlags() {
		return mFlags;
		}
		}

services/core/java/com/android/server/devicestate/OverrideRequestController.java

0 → 100644

+290 −0

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		/*
		* Copyright (C) 2021 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.devicestate;

		import android.annotation.IntDef;
		import android.annotation.NonNull;
		import android.annotation.Nullable;
		import android.hardware.devicestate.DeviceStateRequest;
		import android.os.IBinder;

		import java.io.PrintWriter;
		import java.lang.annotation.Retention;
		import java.lang.annotation.RetentionPolicy;
		import java.util.ArrayList;
		import java.util.List;

		/**
		* Manages the lifecycle of override requests.
		* <p>
		* New requests are added with {@link #addRequest(OverrideRequest)} and are kept active until
		* either:
		* <ul>
		* <li>A new request is added with {@link #addRequest(OverrideRequest)}, in which case the
		* request will become suspended.</li>
		* <li>The request is cancelled with {@link #cancelRequest(IBinder)} or as a side effect
		* of other methods calls, such as {@link #handleProcessDied(int)}.</li>
		* </ul>
		*/
		final class OverrideRequestController {
		static final int STATUS_UNKNOWN = 0;
		/**
		* The request is the top-most request.
		*/
		static final int STATUS_ACTIVE = 1;
		/**
		* The request is still present but is being superseded by another request.
		*/
		static final int STATUS_SUSPENDED = 2;
		/**
		* The request is not longer valid.
		*/
		static final int STATUS_CANCELED = 3;

		@IntDef(prefix = {"STATUS_"}, value = {
		STATUS_UNKNOWN,
		STATUS_ACTIVE,
		STATUS_SUSPENDED,
		STATUS_CANCELED
		})
		@Retention(RetentionPolicy.SOURCE)
		@interface RequestStatus {}

		static String statusToString(@RequestStatus int status) {
		switch (status) {
		case STATUS_ACTIVE:
		return "ACTIVE";
		case STATUS_SUSPENDED:
		return "SUSPENDED";
		case STATUS_CANCELED:
		return "CANCELED";
		case STATUS_UNKNOWN:
		return "UNKNOWN";
		}
		throw new IllegalArgumentException("Unknown status: " + status);
		}

		private final StatusChangeListener mListener;
		private final List<OverrideRequest> mTmpRequestsToCancel = new ArrayList<>();

		// List of override requests with the most recent override request at the end.
		private final ArrayList<OverrideRequest> mRequests = new ArrayList<>();

		OverrideRequestController(@NonNull StatusChangeListener listener) {
		mListener = listener;
		}

		/**
		* Adds a request to the top of the stack and notifies the listener of all changes to request
		* status as a result of this operation.
		*/
		void addRequest(@NonNull OverrideRequest request) {
		mRequests.add(request);
		mListener.onStatusChanged(request, STATUS_ACTIVE);

		if (mRequests.size() > 1) {
		OverrideRequest prevRequest = mRequests.get(mRequests.size() - 2);
		mListener.onStatusChanged(prevRequest, STATUS_SUSPENDED);
		}
		}

		/**
		* Cancels the request with the specified {@code token} and notifies the listener of all changes
		* to request status as a result of this operation.
		*/
		void cancelRequest(@NonNull IBinder token) {
		int index = getRequestIndex(token);
		if (index == -1) {
		return;
		}

		OverrideRequest request = mRequests.remove(index);
		if (index == mRequests.size() && mRequests.size() > 0) {
		// We removed the current active request so we need to set the new active request
		// before cancelling this request.
		OverrideRequest newTop = getLast(mRequests);
		mListener.onStatusChanged(newTop, STATUS_ACTIVE);
		}
		mListener.onStatusChanged(request, STATUS_CANCELED);
		}

		/**
		* Returns {@code true} if this controller is current managing a request with the specified
		* {@code token}, {@code false} otherwise.
		*/
		boolean hasRequest(@NonNull IBinder token) {
		return getRequestIndex(token) != -1;
		}

		/**
		* Notifies the controller that the process with the specified {@code pid} has died. The
		* controller will notify the listener of all changes to request status as a result of this
		* operation.
		*/
		void handleProcessDied(int pid) {
		if (mRequests.isEmpty()) {
		return;
		}

		OverrideRequest prevActiveRequest = getLast(mRequests);
		for (OverrideRequest request : mRequests) {
		if (request.getPid() == pid) {
		mTmpRequestsToCancel.add(request);
		}
		}

		mRequests.removeAll(mTmpRequestsToCancel);
		if (!mRequests.isEmpty()) {
		OverrideRequest newActiveRequest = getLast(mRequests);
		if (newActiveRequest != prevActiveRequest) {
		mListener.onStatusChanged(newActiveRequest, STATUS_ACTIVE);
		}
		}

		for (int i = 0; i < mTmpRequestsToCancel.size(); i++) {
		mListener.onStatusChanged(mTmpRequestsToCancel.get(i), STATUS_CANCELED);
		}
		mTmpRequestsToCancel.clear();
		}

		/**
		* Notifies the controller that the base state has changed. The controller will notify the
		* listener of all changes to request status as a result of this change.
		*
		* @return {@code true} if calling this method has lead to a new active request, {@code false}
		* otherwise.
		*/
		boolean handleBaseStateChanged() {
		if (mRequests.isEmpty()) {
		return false;
		}

		OverrideRequest prevActiveRequest = getLast(mRequests);
		for (int i = 0; i < mRequests.size(); i++) {
		OverrideRequest request = mRequests.get(i);
		if ((request.getFlags() & DeviceStateRequest.FLAG_CANCEL_WHEN_BASE_CHANGES) != 0) {
		mTmpRequestsToCancel.add(request);
		}
		}

		mRequests.removeAll(mTmpRequestsToCancel);
		OverrideRequest newActiveRequest = null;
		if (!mRequests.isEmpty()) {
		newActiveRequest = getLast(mRequests);
		if (newActiveRequest != prevActiveRequest) {
		mListener.onStatusChanged(newActiveRequest, STATUS_ACTIVE);
		}
		}

		for (int i = 0; i < mTmpRequestsToCancel.size(); i++) {
		mListener.onStatusChanged(mTmpRequestsToCancel.get(i), STATUS_CANCELED);
		}
		mTmpRequestsToCancel.clear();

		return newActiveRequest != prevActiveRequest;
		}

		/**
		* Notifies the controller that the set of supported states has changed. The controller will
		* notify the listener of all changes to request status as a result of this change.
		*
		* @return {@code true} if calling this method has lead to a new active request, {@code false}
		* otherwise.
		*/
		boolean handleNewSupportedStates(int[] newSupportedStates) {
		if (mRequests.isEmpty()) {
		return false;
		}

		OverrideRequest prevActiveRequest = getLast(mRequests);
		for (int i = 0; i < mRequests.size(); i++) {
		OverrideRequest request = mRequests.get(i);
		if (!contains(newSupportedStates, request.getRequestedState())) {
		mTmpRequestsToCancel.add(request);
		}
		}

		mRequests.removeAll(mTmpRequestsToCancel);
		OverrideRequest newActiveRequest = null;
		if (!mRequests.isEmpty()) {
		newActiveRequest = getLast(mRequests);
		if (newActiveRequest != prevActiveRequest) {
		mListener.onStatusChanged(newActiveRequest, STATUS_ACTIVE);
		}
		}

		for (int i = 0; i < mTmpRequestsToCancel.size(); i++) {
		mListener.onStatusChanged(mTmpRequestsToCancel.get(i), STATUS_CANCELED);
		}
		mTmpRequestsToCancel.clear();

		return newActiveRequest != prevActiveRequest;
		}

		void dumpInternal(PrintWriter pw) {
		final int requestCount = mRequests.size();
		pw.println();
		pw.println("Override requests: size=" + requestCount);
		for (int i = 0; i < requestCount; i++) {
		OverrideRequest overrideRequest = mRequests.get(i);
		int status = (i == requestCount - 1) ? STATUS_ACTIVE : STATUS_SUSPENDED;
		pw.println(" " + i + ": mPid=" + overrideRequest.getPid()
		+ ", mRequestedState=" + overrideRequest.getRequestedState()
		+ ", mFlags=" + overrideRequest.getFlags()
		+ ", mStatus=" + statusToString(status));
		}
		}

		private int getRequestIndex(@NonNull IBinder token) {
		final int numberOfRequests = mRequests.size();
		if (numberOfRequests == 0) {
		return -1;
		}

		for (int i = 0; i < numberOfRequests; i++) {
		OverrideRequest request = mRequests.get(i);
		if (request.getToken() == token) {
		return i;
		}
		}
		return -1;
		}

		@Nullable
		private static <T> T getLast(List<T> list) {
		return list.size() > 0 ? list.get(list.size() - 1) : null;
		}

		private static boolean contains(int[] array, int value) {
		for (int i = 0; i < array.length; i++) {
		if (array[i] == value) {
		return true;
		}
		}
		return false;
		}

		public interface StatusChangeListener {
		/**
		* Notifies the listener of a change in request status. If a change within the controller
		* causes one request to become active and one to become either suspended or cancelled, this
		* method is guaranteed to be called with the active request first before the suspended or
		* cancelled request.
		*/
		void onStatusChanged(@NonNull OverrideRequest request, @RequestStatus int newStatus);
		}
		}

services/tests/servicestests/src/com/android/server/devicestate/DeviceStateManagerServiceTest.java

+48 −1

Original line number	Diff line number	Diff line
		@@ -69,6 +69,17 @@ public final class DeviceStateManagerServiceTest {
		mProvider = new TestDeviceStateProvider();
		mPolicy = new TestDeviceStatePolicy(mProvider);
		mService = new DeviceStateManagerService(InstrumentationRegistry.getContext(), mPolicy);
		flushHandler(); // Flush the handler to ensure the initial values are committed.
		}

		private void flushHandler() {
		flushHandler(1);
		}

		private void flushHandler(int count) {
		for (int i = 0; i < count; i++) {
		mService.getHandler().runWithScissors(() -> {}, 0);
		}
		}

		@Test
		@@ -80,6 +91,7 @@ public final class DeviceStateManagerServiceTest {
		DEFAULT_DEVICE_STATE.getIdentifier());

		mProvider.setState(OTHER_DEVICE_STATE.getIdentifier());
		flushHandler();
		assertEquals(mService.getCommittedState(), Optional.of(OTHER_DEVICE_STATE));
		assertEquals(mService.getPendingState(), Optional.empty());
		assertEquals(mService.getBaseState(), Optional.of(OTHER_DEVICE_STATE));
		@@ -92,6 +104,7 @@ public final class DeviceStateManagerServiceTest {
		mPolicy.blockConfigure();

		mProvider.setState(OTHER_DEVICE_STATE.getIdentifier());
		flushHandler();
		assertEquals(mService.getCommittedState(), Optional.of(DEFAULT_DEVICE_STATE));
		assertEquals(mService.getPendingState(), Optional.of(OTHER_DEVICE_STATE));
		assertEquals(mService.getBaseState(), Optional.of(OTHER_DEVICE_STATE));
		@@ -99,6 +112,7 @@ public final class DeviceStateManagerServiceTest {
		OTHER_DEVICE_STATE.getIdentifier());

		mProvider.setState(DEFAULT_DEVICE_STATE.getIdentifier());
		flushHandler();
		assertEquals(mService.getCommittedState(), Optional.of(DEFAULT_DEVICE_STATE));
		assertEquals(mService.getPendingState(), Optional.of(OTHER_DEVICE_STATE));
		assertEquals(mService.getBaseState(), Optional.of(DEFAULT_DEVICE_STATE));
		@@ -106,6 +120,7 @@ public final class DeviceStateManagerServiceTest {
		OTHER_DEVICE_STATE.getIdentifier());

		mPolicy.resumeConfigure();
		flushHandler();
		assertEquals(mService.getCommittedState(), Optional.of(DEFAULT_DEVICE_STATE));
		assertEquals(mService.getPendingState(), Optional.empty());
		assertEquals(mService.getBaseState(), Optional.of(DEFAULT_DEVICE_STATE));
		@@ -149,6 +164,7 @@ public final class DeviceStateManagerServiceTest {
		assertEquals(mService.getBaseState(), Optional.of(DEFAULT_DEVICE_STATE));

		mProvider.notifySupportedDeviceStates(new DeviceState[]{ DEFAULT_DEVICE_STATE });
		flushHandler();

		// The current committed and requests states do not change because the current state remains
		// supported.
		@@ -166,6 +182,7 @@ public final class DeviceStateManagerServiceTest {
		mService.getBinderService().registerCallback(callback);

		// An initial callback will be triggered on registration, so we clear it here.
		flushHandler();
		callback.clearLastNotifiedInfo();

		assertEquals(mService.getCommittedState(), Optional.of(DEFAULT_DEVICE_STATE));
		@@ -174,6 +191,7 @@ public final class DeviceStateManagerServiceTest {

		mProvider.notifySupportedDeviceStates(new DeviceState[]{ DEFAULT_DEVICE_STATE,
		OTHER_DEVICE_STATE });
		flushHandler();

		// The current committed and requests states do not change because the current state remains
		// supported.
		@@ -203,12 +221,14 @@ public final class DeviceStateManagerServiceTest {
		mService.getBinderService().registerCallback(callback);

		mProvider.setState(OTHER_DEVICE_STATE.getIdentifier());
		flushHandler();
		assertEquals(callback.getLastNotifiedInfo().baseState,
		OTHER_DEVICE_STATE.getIdentifier());
		assertEquals(callback.getLastNotifiedInfo().currentState,
		OTHER_DEVICE_STATE.getIdentifier());

		mProvider.setState(DEFAULT_DEVICE_STATE.getIdentifier());
		flushHandler();
		assertEquals(callback.getLastNotifiedInfo().baseState,
		DEFAULT_DEVICE_STATE.getIdentifier());
		assertEquals(callback.getLastNotifiedInfo().currentState,
		@@ -216,6 +236,7 @@ public final class DeviceStateManagerServiceTest {

		mPolicy.blockConfigure();
		mProvider.setState(OTHER_DEVICE_STATE.getIdentifier());
		flushHandler();
		// The callback should not have been notified of the state change as the policy is still
		// pending callback.
		assertEquals(callback.getLastNotifiedInfo().baseState,
		@@ -224,6 +245,7 @@ public final class DeviceStateManagerServiceTest {
		DEFAULT_DEVICE_STATE.getIdentifier());

		mPolicy.resumeConfigure();
		flushHandler();
		// Now that the policy is finished processing the callback should be notified of the state
		// change.
		assertEquals(callback.getLastNotifiedInfo().baseState,
		@@ -236,6 +258,7 @@ public final class DeviceStateManagerServiceTest {
		public void registerCallback_emitsInitialValue() throws RemoteException {
		TestDeviceStateManagerCallback callback = new TestDeviceStateManagerCallback();
		mService.getBinderService().registerCallback(callback);
		flushHandler();
		assertNotNull(callback.getLastNotifiedInfo());
		assertEquals(callback.getLastNotifiedInfo().baseState,
		DEFAULT_DEVICE_STATE.getIdentifier());
		@@ -247,6 +270,7 @@ public final class DeviceStateManagerServiceTest {
		public void requestState() throws RemoteException {
		TestDeviceStateManagerCallback callback = new TestDeviceStateManagerCallback();
		mService.getBinderService().registerCallback(callback);
		flushHandler();

		final IBinder token = new Binder();
		assertEquals(callback.getLastNotifiedStatus(token),
		@@ -254,6 +278,10 @@ public final class DeviceStateManagerServiceTest {

		mService.getBinderService().requestState(token, OTHER_DEVICE_STATE.getIdentifier(),
		0 /* flags */);
		// Flush the handler twice. The first flush ensures the request is added and the policy is
		// notified, while the second flush ensures the callback is notified once the change is
		// committed.
		flushHandler(2 /* count */);

		assertEquals(callback.getLastNotifiedStatus(token),
		TestDeviceStateManagerCallback.STATUS_ACTIVE);
		@@ -271,6 +299,7 @@ public final class DeviceStateManagerServiceTest {
		OTHER_DEVICE_STATE.getIdentifier());

		mService.getBinderService().cancelRequest(token);
		flushHandler();

		assertEquals(callback.getLastNotifiedStatus(token),
		TestDeviceStateManagerCallback.STATUS_CANCELED);
		@@ -291,6 +320,7 @@ public final class DeviceStateManagerServiceTest {
		public void requestState_pendingStateAtRequest() throws RemoteException {
		TestDeviceStateManagerCallback callback = new TestDeviceStateManagerCallback();
		mService.getBinderService().registerCallback(callback);
		flushHandler();

		mPolicy.blockConfigure();

		@@ -303,6 +333,10 @@ public final class DeviceStateManagerServiceTest {

		mService.getBinderService().requestState(firstRequestToken,
		OTHER_DEVICE_STATE.getIdentifier(), 0 /* flags */);
		// Flush the handler twice. The first flush ensures the request is added and the policy is
		// notified, while the second flush ensures the callback is notified once the change is
		// committed.
		flushHandler(2 /* count */);

		assertEquals(mService.getCommittedState(), Optional.of(DEFAULT_DEVICE_STATE));
		assertEquals(mService.getPendingState(), Optional.of(OTHER_DEVICE_STATE));
		@@ -312,8 +346,8 @@ public final class DeviceStateManagerServiceTest {

		mService.getBinderService().requestState(secondRequestToken,
		DEFAULT_DEVICE_STATE.getIdentifier(), 0 /* flags */);

		mPolicy.resumeConfigureOnce();
		flushHandler();

		// First request status is now suspended as there is another pending request.
		assertEquals(callback.getLastNotifiedStatus(firstRequestToken),
		@@ -330,6 +364,7 @@ public final class DeviceStateManagerServiceTest {
		DEFAULT_DEVICE_STATE.getIdentifier());

		mPolicy.resumeConfigure();
		flushHandler();

		assertEquals(mService.getCommittedState(), Optional.of(DEFAULT_DEVICE_STATE));
		assertEquals(mService.getPendingState(), Optional.empty());
		@@ -339,6 +374,7 @@ public final class DeviceStateManagerServiceTest {

		// Now cancel the second request to make the first request active.
		mService.getBinderService().cancelRequest(secondRequestToken);
		flushHandler();

		assertEquals(callback.getLastNotifiedStatus(firstRequestToken),
		TestDeviceStateManagerCallback.STATUS_ACTIVE);
		@@ -356,6 +392,7 @@ public final class DeviceStateManagerServiceTest {
		public void requestState_sameAsBaseState() throws RemoteException {
		TestDeviceStateManagerCallback callback = new TestDeviceStateManagerCallback();
		mService.getBinderService().registerCallback(callback);
		flushHandler();

		final IBinder token = new Binder();
		assertEquals(callback.getLastNotifiedStatus(token),
		@@ -363,6 +400,7 @@ public final class DeviceStateManagerServiceTest {

		mService.getBinderService().requestState(token, DEFAULT_DEVICE_STATE.getIdentifier(),
		0 /* flags */);
		flushHandler();

		assertEquals(callback.getLastNotifiedStatus(token),
		TestDeviceStateManagerCallback.STATUS_ACTIVE);
		@@ -372,6 +410,7 @@ public final class DeviceStateManagerServiceTest {
		public void requestState_flagCancelWhenBaseChanges() throws RemoteException {
		TestDeviceStateManagerCallback callback = new TestDeviceStateManagerCallback();
		mService.getBinderService().registerCallback(callback);
		flushHandler();

		final IBinder token = new Binder();
		assertEquals(callback.getLastNotifiedStatus(token),
		@@ -379,6 +418,10 @@ public final class DeviceStateManagerServiceTest {

		mService.getBinderService().requestState(token, OTHER_DEVICE_STATE.getIdentifier(),
		DeviceStateRequest.FLAG_CANCEL_WHEN_BASE_CHANGES);
		// Flush the handler twice. The first flush ensures the request is added and the policy is
		// notified, while the second flush ensures the callback is notified once the change is
		// committed.
		flushHandler(2 /* count */);

		assertEquals(callback.getLastNotifiedStatus(token),
		TestDeviceStateManagerCallback.STATUS_ACTIVE);
		@@ -391,6 +434,7 @@ public final class DeviceStateManagerServiceTest {
		OTHER_DEVICE_STATE.getIdentifier());

		mProvider.setState(OTHER_DEVICE_STATE.getIdentifier());
		flushHandler();

		// Request is canceled because the base state changed.
		assertEquals(callback.getLastNotifiedStatus(token),
		@@ -407,6 +451,7 @@ public final class DeviceStateManagerServiceTest {
		public void requestState_becomesUnsupported() throws RemoteException {
		TestDeviceStateManagerCallback callback = new TestDeviceStateManagerCallback();
		mService.getBinderService().registerCallback(callback);
		flushHandler();

		final IBinder token = new Binder();
		assertEquals(callback.getLastNotifiedStatus(token),
		@@ -414,6 +459,7 @@ public final class DeviceStateManagerServiceTest {

		mService.getBinderService().requestState(token, OTHER_DEVICE_STATE.getIdentifier(),
		0 /* flags */);
		flushHandler();

		assertEquals(callback.getLastNotifiedStatus(token),
		TestDeviceStateManagerCallback.STATUS_ACTIVE);
		@@ -425,6 +471,7 @@ public final class DeviceStateManagerServiceTest {
		OTHER_DEVICE_STATE.getIdentifier());

		mProvider.notifySupportedDeviceStates(new DeviceState[]{ DEFAULT_DEVICE_STATE });
		flushHandler();

		// Request is canceled because the state is no longer supported.
		assertEquals(callback.getLastNotifiedStatus(token),

services/tests/servicestests/src/com/android/server/devicestate/OverrideRequestControllerTest.java

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