services/java/com/android/server/SensorService.java - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 2008 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;

 import android.content.Context;
 import android.hardware.ISensorService;
 import android.os.Binder;
 import android.os.Bundle;
 import android.os.RemoteException;
 import android.os.IBinder;
 import android.util.Config;
 import android.util.Slog;
 import android.util.PrintWriterPrinter;
 import android.util.Printer;

 import java.io.FileDescriptor;
 import java.io.PrintWriter;
 import java.util.ArrayList;

 import com.android.internal.app.IBatteryStats;
 import com.android.server.am.BatteryStatsService;


 /**
  * Class that manages the device's sensors. It register clients and activate
  * the needed sensors. The sensor events themselves are not broadcasted from
  * this service, instead, a file descriptor is provided to each client they
  * can read events from.
  */

 class SensorService extends ISensorService.Stub {
     static final String TAG = SensorService.class.getSimpleName();
     private static final boolean DEBUG = false;
     private static final boolean localLOGV = DEBUG ? Config.LOGD : Config.LOGV;
     private static final int SENSOR_DISABLE = -1;
     private int mCurrentDelay = 0;

     /**
      * Battery statistics to be updated when sensors are enabled and disabled.
      */
     final IBatteryStats mBatteryStats = BatteryStatsService.getService();

     private final class Listener implements IBinder.DeathRecipient {
         final IBinder mToken;
         final int mUid;

         int mSensors = 0;
         int mDelay = 0x7FFFFFFF;

         Listener(IBinder token, int uid) {
             mToken = token;
             mUid = uid;
         }

         void addSensor(int sensor, int delay) {
             mSensors |= (1<<sensor);
             if (delay < mDelay)
             	mDelay = delay;
         }

         void removeSensor(int sensor) {
             mSensors &= ~(1<<sensor);
         }

         boolean hasSensor(int sensor) {
             return ((mSensors & (1<<sensor)) != 0);
         }

         public void binderDied() {
             if (localLOGV) Slog.d(TAG, "sensor listener died");
             synchronized(mListeners) {
                 mListeners.remove(this);
                 mToken.unlinkToDeath(this, 0);
                 // go through the lists of sensors used by the listener that
                 // died and deactivate them.
                 for (int sensor=0 ; sensor<32 && mSensors!=0 ; sensor++) {
                     if (hasSensor(sensor)) {
                         removeSensor(sensor);
                         deactivateIfUnusedLocked(sensor);
                         try {
                             mBatteryStats.noteStopSensor(mUid, sensor);
                         } catch (RemoteException e) {
                             // oops. not a big deal.
                         }
                     }
                 }
                 if (mListeners.size() == 0) {
                     _sensors_control_wake();
                     _sensors_control_close();
                 } else {
                     // TODO: we should recalculate the delay, since removing
                     // a listener may increase the overall rate.
                 }
                 mListeners.notify();
             }
         }
     }

     @SuppressWarnings("unused")
     public SensorService(Context context) {
         if (localLOGV) Slog.d(TAG, "SensorService startup");
         _sensors_control_init();
     }

     public Bundle getDataChannel() throws RemoteException {
         // synchronize so we do not require sensor HAL to be thread-safe.
         synchronized(mListeners) {
             return _sensors_control_open();
         }
     }

     public boolean enableSensor(IBinder binder, String name, int sensor, int enable)
             throws RemoteException {

         if (localLOGV) Slog.d(TAG, "enableSensor " + name + "(#" + sensor + ") " + enable);

         if (binder == null) {
             Slog.e(TAG, "listener is null (sensor=" + name + ", id=" + sensor + ")");
             return false;
         }

         if (enable < 0 && (enable != SENSOR_DISABLE)) {
             Slog.e(TAG, "invalid enable parameter (enable=" + enable +
                     ", sensor=" + name + ", id=" + sensor + ")");
             return false;
         }

         boolean res;
         int uid = Binder.getCallingUid();
         synchronized(mListeners) {
             res = enableSensorInternalLocked(binder, uid, name, sensor, enable);
             if (res == true) {
                 // Inform battery statistics service of status change
                 long identity = Binder.clearCallingIdentity();
                 if (enable == SENSOR_DISABLE) {
                     mBatteryStats.noteStopSensor(uid, sensor);
                 } else {
                     mBatteryStats.noteStartSensor(uid, sensor);
                 }
                 Binder.restoreCallingIdentity(identity);
             }
         }
         return res;
     }

     private boolean enableSensorInternalLocked(IBinder binder, int uid,
             String name, int sensor, int enable) throws RemoteException {

         // check if we have this listener
         Listener l = null;
         for (Listener listener : mListeners) {
             if (binder == listener.mToken) {
                 l = listener;
                 break;
             }
         }

         if (enable != SENSOR_DISABLE) {
             // Activate the requested sensor
             if (_sensors_control_activate(sensor, true) == false) {
                 Slog.w(TAG, "could not enable sensor " + sensor);
                 return false;
             }

             if (l == null) {
                 /*
                  * we don't have a listener for this binder yet, so
                  * create a new one and add it to the list.
                  */
                 l = new Listener(binder, uid);
                 binder.linkToDeath(l, 0);
                 mListeners.add(l);
                 mListeners.notify();
             }

             // take note that this sensor is now used by this client
             l.addSensor(sensor, enable);

         } else {

             if (l == null) {
                 /*
                  *  This client isn't in the list, this usually happens
                  *  when enabling the sensor failed, but the client
                  *  didn't handle the error and later tries to shut that
                  *  sensor off.
                  */
                 Slog.w(TAG, "listener with binder " + binder +
                         ", doesn't exist (sensor=" + name +
                         ", id=" + sensor + ")");
                 return false;
             }

             // remove this sensor from this client
             l.removeSensor(sensor);

             // see if we need to deactivate this sensors=
             deactivateIfUnusedLocked(sensor);

             // if the listener doesn't have any more sensors active
             // we can get rid of it
             if (l.mSensors == 0) {
                 // we won't need this death notification anymore
                 binder.unlinkToDeath(l, 0);
                 // remove the listener from the list
                 mListeners.remove(l);
                 // and if the list is empty, turn off the whole sensor h/w
                 if (mListeners.size() == 0) {
                     _sensors_control_wake();
                     _sensors_control_close();
                 }
                 mListeners.notify();
             }
         }

         // calculate and set the new delay
         int minDelay = 0x7FFFFFFF;
         for (Listener listener : mListeners) {
             if (listener.mDelay < minDelay)
                 minDelay = listener.mDelay;
         }
         if (minDelay != 0x7FFFFFFF) {
             mCurrentDelay = minDelay;
             _sensors_control_set_delay(minDelay);
         }

         return true;
     }

     private void deactivateIfUnusedLocked(int sensor) {
         int size = mListeners.size();
         for (int i=0 ; i<size ; i++) {
             if (mListeners.get(i).hasSensor(sensor)) {
                 // this sensor is still in use, don't turn it off
                 return;
             }
         }
         if (_sensors_control_activate(sensor, false) == false) {
             Slog.w(TAG, "could not disable sensor " + sensor);
         }
     }

     @Override
     protected void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
         synchronized (mListeners) {
             Printer pr = new PrintWriterPrinter(pw);
             int c = 0;
             pr.println(mListeners.size() + " listener(s), delay=" + mCurrentDelay + " ms");
             for (Listener l : mListeners) {
                 pr.println("listener[" + c + "] " +
                         "sensors=0x" + Integer.toString(l.mSensors, 16) +
                         ", uid=" + l.mUid +
                         ", delay=" +
                         l.mDelay + " ms");
                 c++;
             }
         }
     }

     private ArrayList<Listener> mListeners = new ArrayList<Listener>();

     private static native int _sensors_control_init();
     private static native Bundle _sensors_control_open();
     private static native int _sensors_control_close();
     private static native boolean _sensors_control_activate(int sensor, boolean activate);
     private static native int _sensors_control_set_delay(int ms);
     private static native int _sensors_control_wake();
 }
	/*
	* Copyright (C) 2008 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;

	import android.content.Context;
	import android.hardware.ISensorService;
	import android.os.Binder;
	import android.os.Bundle;
	import android.os.RemoteException;
	import android.os.IBinder;
	import android.util.Config;
	import android.util.Slog;
	import android.util.PrintWriterPrinter;
	import android.util.Printer;

	import java.io.FileDescriptor;
	import java.io.PrintWriter;
	import java.util.ArrayList;

	import com.android.internal.app.IBatteryStats;
	import com.android.server.am.BatteryStatsService;


	/**
	* Class that manages the device's sensors. It register clients and activate
	* the needed sensors. The sensor events themselves are not broadcasted from
	* this service, instead, a file descriptor is provided to each client they
	* can read events from.
	*/

	class SensorService extends ISensorService.Stub {
	static final String TAG = SensorService.class.getSimpleName();
	private static final boolean DEBUG = false;
	private static final boolean localLOGV = DEBUG ? Config.LOGD : Config.LOGV;
	private static final int SENSOR_DISABLE = -1;
	private int mCurrentDelay = 0;

	/**
	* Battery statistics to be updated when sensors are enabled and disabled.
	*/
	final IBatteryStats mBatteryStats = BatteryStatsService.getService();

	private final class Listener implements IBinder.DeathRecipient {
	final IBinder mToken;
	final int mUid;

	int mSensors = 0;
	int mDelay = 0x7FFFFFFF;

	Listener(IBinder token, int uid) {
	mToken = token;
	mUid = uid;
	}

	void addSensor(int sensor, int delay) {
	mSensors \|= (1<<sensor);
	if (delay < mDelay)
	mDelay = delay;
	}

	void removeSensor(int sensor) {
	mSensors &= ~(1<<sensor);
	}

	boolean hasSensor(int sensor) {
	return ((mSensors & (1<<sensor)) != 0);
	}

	public void binderDied() {
	if (localLOGV) Slog.d(TAG, "sensor listener died");
	synchronized(mListeners) {
	mListeners.remove(this);
	mToken.unlinkToDeath(this, 0);
	// go through the lists of sensors used by the listener that
	// died and deactivate them.
	for (int sensor=0 ; sensor<32 && mSensors!=0 ; sensor++) {
	if (hasSensor(sensor)) {
	removeSensor(sensor);
	deactivateIfUnusedLocked(sensor);
	try {
	mBatteryStats.noteStopSensor(mUid, sensor);
	} catch (RemoteException e) {
	// oops. not a big deal.
	}
	}
	}
	if (mListeners.size() == 0) {
	_sensors_control_wake();
	_sensors_control_close();
	} else {
	// TODO: we should recalculate the delay, since removing
	// a listener may increase the overall rate.
	}
	mListeners.notify();
	}
	}
	}

	@SuppressWarnings("unused")
	public SensorService(Context context) {
	if (localLOGV) Slog.d(TAG, "SensorService startup");
	_sensors_control_init();
	}

	public Bundle getDataChannel() throws RemoteException {
	// synchronize so we do not require sensor HAL to be thread-safe.
	synchronized(mListeners) {
	return _sensors_control_open();
	}
	}

	public boolean enableSensor(IBinder binder, String name, int sensor, int enable)
	throws RemoteException {

	if (localLOGV) Slog.d(TAG, "enableSensor " + name + "(#" + sensor + ") " + enable);

	if (binder == null) {
	Slog.e(TAG, "listener is null (sensor=" + name + ", id=" + sensor + ")");
	return false;
	}

	if (enable < 0 && (enable != SENSOR_DISABLE)) {
	Slog.e(TAG, "invalid enable parameter (enable=" + enable +
	", sensor=" + name + ", id=" + sensor + ")");
	return false;
	}

	boolean res;
	int uid = Binder.getCallingUid();
	synchronized(mListeners) {
	res = enableSensorInternalLocked(binder, uid, name, sensor, enable);
	if (res == true) {
	// Inform battery statistics service of status change
	long identity = Binder.clearCallingIdentity();
	if (enable == SENSOR_DISABLE) {
	mBatteryStats.noteStopSensor(uid, sensor);
	} else {
	mBatteryStats.noteStartSensor(uid, sensor);
	}
	Binder.restoreCallingIdentity(identity);
	}
	}
	return res;
	}

	private boolean enableSensorInternalLocked(IBinder binder, int uid,
	String name, int sensor, int enable) throws RemoteException {

	// check if we have this listener
	Listener l = null;
	for (Listener listener : mListeners) {
	if (binder == listener.mToken) {
	l = listener;
	break;
	}
	}

	if (enable != SENSOR_DISABLE) {
	// Activate the requested sensor
	if (_sensors_control_activate(sensor, true) == false) {
	Slog.w(TAG, "could not enable sensor " + sensor);
	return false;
	}

	if (l == null) {
	/*
	* we don't have a listener for this binder yet, so
	* create a new one and add it to the list.
	*/
	l = new Listener(binder, uid);
	binder.linkToDeath(l, 0);
	mListeners.add(l);
	mListeners.notify();
	}

	// take note that this sensor is now used by this client
	l.addSensor(sensor, enable);

	} else {

	if (l == null) {
	/*
	* This client isn't in the list, this usually happens
	* when enabling the sensor failed, but the client
	* didn't handle the error and later tries to shut that
	* sensor off.
	*/
	Slog.w(TAG, "listener with binder " + binder +
	", doesn't exist (sensor=" + name +
	", id=" + sensor + ")");
	return false;
	}

	// remove this sensor from this client
	l.removeSensor(sensor);

	// see if we need to deactivate this sensors=
	deactivateIfUnusedLocked(sensor);

	// if the listener doesn't have any more sensors active
	// we can get rid of it
	if (l.mSensors == 0) {
	// we won't need this death notification anymore
	binder.unlinkToDeath(l, 0);
	// remove the listener from the list
	mListeners.remove(l);
	// and if the list is empty, turn off the whole sensor h/w
	if (mListeners.size() == 0) {
	_sensors_control_wake();
	_sensors_control_close();
	}
	mListeners.notify();
	}
	}

	// calculate and set the new delay
	int minDelay = 0x7FFFFFFF;
	for (Listener listener : mListeners) {
	if (listener.mDelay < minDelay)
	minDelay = listener.mDelay;
	}
	if (minDelay != 0x7FFFFFFF) {
	mCurrentDelay = minDelay;
	_sensors_control_set_delay(minDelay);
	}

	return true;
	}

	private void deactivateIfUnusedLocked(int sensor) {
	int size = mListeners.size();
	for (int i=0 ; i<size ; i++) {
	if (mListeners.get(i).hasSensor(sensor)) {
	// this sensor is still in use, don't turn it off
	return;
	}
	}
	if (_sensors_control_activate(sensor, false) == false) {
	Slog.w(TAG, "could not disable sensor " + sensor);
	}
	}

	@Override
	protected void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
	synchronized (mListeners) {
	Printer pr = new PrintWriterPrinter(pw);
	int c = 0;
	pr.println(mListeners.size() + " listener(s), delay=" + mCurrentDelay + " ms");
	for (Listener l : mListeners) {
	pr.println("listener[" + c + "] " +
	"sensors=0x" + Integer.toString(l.mSensors, 16) +
	", uid=" + l.mUid +
	", delay=" +
	l.mDelay + " ms");
	c++;
	}
	}
	}

	private ArrayList<Listener> mListeners = new ArrayList<Listener>();

	private static native int _sensors_control_init();
	private static native Bundle _sensors_control_open();
	private static native int _sensors_control_close();
	private static native boolean _sensors_control_activate(int sensor, boolean activate);
	private static native int _sensors_control_set_delay(int ms);
	private static native int _sensors_control_wake();
	}