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/*
* 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.app.ActivityManagerNative;
import android.content.Context;
import android.content.Intent;
import android.os.Handler;
import android.os.Message;
import android.os.UEventObserver;
import android.util.Log;
import android.media.AudioManager;
import java.io.FileReader;
import java.io.FileNotFoundException;
/**
* <p>HeadsetObserver monitors for a wired headset.
*/
class HeadsetObserver extends UEventObserver {
private static final String TAG = HeadsetObserver.class.getSimpleName();
private static final String HEADSET_UEVENT_MATCH = "DEVPATH=/devices/virtual/switch/h2w";
private static final String HEADSET_STATE_PATH = "/sys/class/switch/h2w/state";
private static final String HEADSET_NAME_PATH = "/sys/class/switch/h2w/name";
private Context mContext;
private int mHeadsetState;
private String mHeadsetName;
private boolean mAudioRouteNeedsUpdate;
private AudioManager mAudioManager;
public HeadsetObserver(Context context) {
mContext = context;
startObserving(HEADSET_UEVENT_MATCH);
init(); // set initial status
}
@Override
public void onUEvent(UEventObserver.UEvent event) {
Log.v(TAG, "Headset UEVENT: " + event.toString());
try {
update(event.get("SWITCH_NAME"), Integer.parseInt(event.get("SWITCH_STATE")));
} catch (NumberFormatException e) {
Log.e(TAG, "Could not parse switch state from event " + event);
}
}
private synchronized final void init() {
char[] buffer = new char[1024];
String newName = mHeadsetName;
int newState = mHeadsetState;
try {
FileReader file = new FileReader(HEADSET_STATE_PATH);
int len = file.read(buffer, 0, 1024);
newState = Integer.valueOf((new String(buffer, 0, len)).trim());
file = new FileReader(HEADSET_NAME_PATH);
len = file.read(buffer, 0, 1024);
newName = new String(buffer, 0, len).trim();
} catch (FileNotFoundException e) {
Log.w(TAG, "This kernel does not have wired headset support");
} catch (Exception e) {
Log.e(TAG, "" , e);
}
mAudioManager = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE);
update(newName, newState);
}
private synchronized final void update(String newName, int newState) {
if (newName != mHeadsetName || newState != mHeadsetState) {
boolean isUnplug = (newState == 0 && mHeadsetState == 1);
mHeadsetName = newName;
mHeadsetState = newState;
mAudioRouteNeedsUpdate = true;
sendIntent(isUnplug);
if (isUnplug) {
// It often takes >200ms to flush the audio pipeline after apps
// pause audio playback, but audio route changes are immediate,
// so delay the route change by 400ms.
// This could be improved once the audio sub-system provides an
// interface to clear the audio pipeline.
mHandler.sendEmptyMessageDelayed(0, 400);
} else {
updateAudioRoute();
}
}
}
private synchronized final void sendIntent(boolean isUnplug) {
// Pack up the values and broadcast them to everyone
Intent intent = new Intent(Intent.ACTION_HEADSET_PLUG);
intent.addFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY);
intent.putExtra("state", mHeadsetState);
intent.putExtra("name", mHeadsetName);
// TODO: Should we require a permission?
ActivityManagerNative.broadcastStickyIntent(intent, null);
if (isUnplug) {
intent = new Intent(AudioManager.ACTION_AUDIO_BECOMING_NOISY);
mContext.sendBroadcast(intent);
}
}
private synchronized final void updateAudioRoute() {
if (mAudioRouteNeedsUpdate) {
mAudioManager.setWiredHeadsetOn(mHeadsetState == 1);
mAudioRouteNeedsUpdate = false;
}
}
private final Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
updateAudioRoute();
}
};
}
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