| /* |
| * Copyright (C) 2006 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 android.os; |
| |
| import com.google.android.collect.Maps; |
| |
| import android.annotation.UnsupportedAppUsage; |
| import java.util.HashMap; |
| import java.util.concurrent.TimeoutException; |
| |
| /** |
| * Controls and utilities for low-level {@code init} services. |
| * |
| * @hide |
| */ |
| public class SystemService { |
| |
| private static HashMap<String, State> sStates = Maps.newHashMap(); |
| |
| /** |
| * State of a known {@code init} service. |
| */ |
| public enum State { |
| RUNNING("running"), |
| STOPPING("stopping"), |
| STOPPED("stopped"), |
| RESTARTING("restarting"); |
| |
| State(String state) { |
| sStates.put(state, this); |
| } |
| } |
| |
| private static Object sPropertyLock = new Object(); |
| |
| static { |
| SystemProperties.addChangeCallback(new Runnable() { |
| @Override |
| public void run() { |
| synchronized (sPropertyLock) { |
| sPropertyLock.notifyAll(); |
| } |
| } |
| }); |
| } |
| |
| /** Request that the init daemon start a named service. */ |
| @UnsupportedAppUsage |
| public static void start(String name) { |
| SystemProperties.set("ctl.start", name); |
| } |
| |
| /** Request that the init daemon stop a named service. */ |
| @UnsupportedAppUsage |
| public static void stop(String name) { |
| SystemProperties.set("ctl.stop", name); |
| } |
| |
| /** Request that the init daemon restart a named service. */ |
| public static void restart(String name) { |
| SystemProperties.set("ctl.restart", name); |
| } |
| |
| /** |
| * Return current state of given service. |
| */ |
| public static State getState(String service) { |
| final String rawState = SystemProperties.get("init.svc." + service); |
| final State state = sStates.get(rawState); |
| if (state != null) { |
| return state; |
| } else { |
| return State.STOPPED; |
| } |
| } |
| |
| /** |
| * Check if given service is {@link State#STOPPED}. |
| */ |
| public static boolean isStopped(String service) { |
| return State.STOPPED.equals(getState(service)); |
| } |
| |
| /** |
| * Check if given service is {@link State#RUNNING}. |
| */ |
| public static boolean isRunning(String service) { |
| return State.RUNNING.equals(getState(service)); |
| } |
| |
| /** |
| * Wait until given service has entered specific state. |
| */ |
| public static void waitForState(String service, State state, long timeoutMillis) |
| throws TimeoutException { |
| final long endMillis = SystemClock.elapsedRealtime() + timeoutMillis; |
| while (true) { |
| synchronized (sPropertyLock) { |
| final State currentState = getState(service); |
| if (state.equals(currentState)) { |
| return; |
| } |
| |
| if (SystemClock.elapsedRealtime() >= endMillis) { |
| throw new TimeoutException("Service " + service + " currently " + currentState |
| + "; waited " + timeoutMillis + "ms for " + state); |
| } |
| |
| try { |
| sPropertyLock.wait(timeoutMillis); |
| } catch (InterruptedException e) { |
| } |
| } |
| } |
| } |
| |
| /** |
| * Wait until any of given services enters {@link State#STOPPED}. |
| */ |
| public static void waitForAnyStopped(String... services) { |
| while (true) { |
| synchronized (sPropertyLock) { |
| for (String service : services) { |
| if (State.STOPPED.equals(getState(service))) { |
| return; |
| } |
| } |
| |
| try { |
| sPropertyLock.wait(); |
| } catch (InterruptedException e) { |
| } |
| } |
| } |
| } |
| } |