src.android.telephony.TelephonyScanManager Maven / Gradle / Ivy
/*
* Copyright (C) 2017 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.telephony;
import static com.android.internal.util.Preconditions.checkNotNull;
import android.annotation.Nullable;
import android.os.Binder;
import android.os.Bundle;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.Looper;
import android.os.Message;
import android.os.Messenger;
import android.os.Parcelable;
import android.os.RemoteException;
import android.util.SparseArray;
import com.android.internal.annotations.GuardedBy;
import com.android.internal.telephony.ITelephony;
import com.android.telephony.Rlog;
import java.util.Arrays;
import java.util.List;
import java.util.concurrent.Executor;
/**
* Manages the radio access network scan requests and callbacks.
*/
public final class TelephonyScanManager {
private static final String TAG = "TelephonyScanManager";
/** @hide */
public static final String SCAN_RESULT_KEY = "scanResult";
/** @hide */
public static final int CALLBACK_SCAN_RESULTS = 1;
/** @hide */
public static final int CALLBACK_SCAN_ERROR = 2;
/** @hide */
public static final int CALLBACK_SCAN_COMPLETE = 3;
/** @hide */
public static final int CALLBACK_RESTRICTED_SCAN_RESULTS = 4;
/** @hide */
public static final int CALLBACK_TELEPHONY_DIED = 5;
/** @hide */
public static final int INVALID_SCAN_ID = -1;
/**
* The caller of
* {@link
* TelephonyManager#requestNetworkScan(NetworkScanRequest, Executor, NetworkScanCallback)}
* should implement and provide this callback so that the scan results or errors can be
* returned.
*/
public static abstract class NetworkScanCallback {
/** Returns the scan results to the user, this callback will be called multiple times. */
public void onResults(List results) {}
/**
* Informs the user that the scan has stopped.
*
* This callback will be called when the scan is finished or cancelled by the user.
* The related NetworkScanRequest will be deleted after this callback.
*/
public void onComplete() {}
/**
* Informs the user that there is some error about the scan.
*
* This callback will be called whenever there is any error about the scan, and the scan
* will be terminated. onComplete() will NOT be called.
*
* @param error Error code when the scan is failed, as defined in {@link NetworkScan}.
*/
public void onError(@NetworkScan.ScanErrorCode int error) {}
}
private static class NetworkScanInfo {
private final NetworkScanRequest mRequest;
private final Executor mExecutor;
private final NetworkScanCallback mCallback;
NetworkScanInfo(
NetworkScanRequest request, Executor executor, NetworkScanCallback callback) {
mRequest = request;
mExecutor = executor;
mCallback = callback;
}
}
private final Looper mLooper;
private final Handler mHandler;
private final Messenger mMessenger;
private final SparseArray mScanInfo = new SparseArray();
private final Binder.DeathRecipient mDeathRecipient;
public TelephonyScanManager() {
HandlerThread thread = new HandlerThread(TAG);
thread.start();
mLooper = thread.getLooper();
mHandler = new Handler(mLooper) {
@Override
public void handleMessage(Message message) {
checkNotNull(message, "message cannot be null");
if (message.what == CALLBACK_TELEPHONY_DIED) {
// If there are no objects in mScanInfo then binder death will simply return.
synchronized (mScanInfo) {
for (int i = 0; i < mScanInfo.size(); i++) {
NetworkScanInfo nsi = mScanInfo.valueAt(i);
// At this point we go into panic mode and ignore errors that would
// normally stop the show in order to try and clean up as gracefully
// as possible.
if (nsi == null) continue; // shouldn't be possible
Executor e = nsi.mExecutor;
NetworkScanCallback cb = nsi.mCallback;
if (e == null || cb == null) continue;
try {
e.execute(
() -> cb.onError(NetworkScan.ERROR_MODEM_UNAVAILABLE));
} catch (java.util.concurrent.RejectedExecutionException ignore) {
// ignore so that we can continue
}
}
mScanInfo.clear();
}
return;
}
NetworkScanInfo nsi;
synchronized (mScanInfo) {
nsi = mScanInfo.get(message.arg2);
}
if (nsi == null) {
throw new RuntimeException(
"Failed to find NetworkScanInfo with id " + message.arg2);
}
NetworkScanCallback callback = nsi.mCallback;
Executor executor = nsi.mExecutor;
if (callback == null) {
throw new RuntimeException(
"Failed to find NetworkScanCallback with id " + message.arg2);
}
if (executor == null) {
throw new RuntimeException(
"Failed to find Executor with id " + message.arg2);
}
switch (message.what) {
case CALLBACK_RESTRICTED_SCAN_RESULTS:
case CALLBACK_SCAN_RESULTS:
try {
final Bundle b = message.getData();
final Parcelable[] parcelables = b.getParcelableArray(SCAN_RESULT_KEY);
CellInfo[] ci = new CellInfo[parcelables.length];
for (int i = 0; i < parcelables.length; i++) {
ci[i] = (CellInfo) parcelables[i];
}
executor.execute(() -> {
Rlog.d(TAG, "onResults: " + ci.toString());
callback.onResults(Arrays.asList(ci));
});
} catch (Exception e) {
Rlog.e(TAG, "Exception in networkscan callback onResults", e);
}
break;
case CALLBACK_SCAN_ERROR:
try {
final int errorCode = message.arg1;
executor.execute(() -> {
Rlog.d(TAG, "onError: " + errorCode);
callback.onError(errorCode);
});
synchronized (mScanInfo) {
mScanInfo.remove(message.arg2);
}
} catch (Exception e) {
Rlog.e(TAG, "Exception in networkscan callback onError", e);
}
break;
case CALLBACK_SCAN_COMPLETE:
try {
executor.execute(() -> {
Rlog.d(TAG, "onComplete");
callback.onComplete();
});
synchronized (mScanInfo) {
mScanInfo.remove(message.arg2);
}
} catch (Exception e) {
Rlog.e(TAG, "Exception in networkscan callback onComplete", e);
}
break;
default:
Rlog.e(TAG, "Unhandled message " + Integer.toHexString(message.what));
break;
}
}
};
mMessenger = new Messenger(mHandler);
mDeathRecipient = new Binder.DeathRecipient() {
@Override
public void binderDied() {
mHandler.obtainMessage(CALLBACK_TELEPHONY_DIED).sendToTarget();
}
};
}
/**
* Request a network scan.
*
* This method is asynchronous, so the network scan results will be returned by callback.
* The returned NetworkScan will contain a callback method which can be used to stop the scan.
*
*
* Requires Permission:
* {@link android.Manifest.permission#ACCESS_FINE_LOCATION} and
* {@link android.Manifest.permission#MODIFY_PHONE_STATE MODIFY_PHONE_STATE}
* Or the calling app has carrier privileges. @see #hasCarrierPrivileges
*
* @param request Contains all the RAT with bands/channels that need to be scanned.
* @param callback Returns network scan results or errors.
* @param callingPackage The package name of the caller
* @param callingFeatureId The feature id inside of the calling package
* @return A NetworkScan obj which contains a callback which can stop the scan.
* @hide
*/
public NetworkScan requestNetworkScan(int subId,
NetworkScanRequest request, Executor executor, NetworkScanCallback callback,
String callingPackage, @Nullable String callingFeatureId) {
try {
final ITelephony telephony = getITelephony();
if (telephony == null) return null;
int scanId = telephony.requestNetworkScan(
subId, request, mMessenger, new Binder(), callingPackage,
callingFeatureId);
if (scanId == INVALID_SCAN_ID) {
Rlog.e(TAG, "Failed to initiate network scan");
return null;
}
synchronized (mScanInfo) {
// We link to death whenever a scan is started to ensure that we are linked
// at the point that phone process death might matter.
// We never unlink because:
// - Duplicate links to death with the same callback do not result in
// extraneous callbacks (the tracking de-dupes).
// - Receiving binderDeath() when no scans are active is a no-op.
telephony.asBinder().linkToDeath(mDeathRecipient, 0);
saveScanInfo(scanId, request, executor, callback);
return new NetworkScan(scanId, subId);
}
} catch (RemoteException ex) {
Rlog.e(TAG, "requestNetworkScan RemoteException", ex);
} catch (NullPointerException ex) {
Rlog.e(TAG, "requestNetworkScan NPE", ex);
}
return null;
}
@GuardedBy("mScanInfo")
private void saveScanInfo(
int id, NetworkScanRequest request, Executor executor, NetworkScanCallback callback) {
mScanInfo.put(id, new NetworkScanInfo(request, executor, callback));
}
private ITelephony getITelephony() {
return ITelephony.Stub.asInterface(
TelephonyFrameworkInitializer
.getTelephonyServiceManager()
.getTelephonyServiceRegisterer()
.get());
}
}