Disallow duplicate listeners for WifiScanner.
Bug:26663377
Change-Id: I2eea0fd3532c45f493aad7c0d5c28bda07f5bfed
diff --git a/api/system-current.txt b/api/system-current.txt
index fc9ae9b..866e598 100644
--- a/api/system-current.txt
+++ b/api/system-current.txt
@@ -21209,6 +21209,7 @@
method public void stopTrackingWifiChange(android.net.wifi.WifiScanner.WifiChangeListener);
field public static final int MAX_SCAN_PERIOD_MS = 1024000; // 0xfa000
field public static final int MIN_SCAN_PERIOD_MS = 1000; // 0x3e8
+ field public static final int REASON_DUPLICATE_REQEUST = -5; // 0xfffffffb
field public static final int REASON_INVALID_LISTENER = -2; // 0xfffffffe
field public static final int REASON_INVALID_REQUEST = -3; // 0xfffffffd
field public static final int REASON_NOT_AUTHORIZED = -4; // 0xfffffffc
diff --git a/wifi/java/android/net/wifi/WifiScanner.java b/wifi/java/android/net/wifi/WifiScanner.java
index 44be671..3cab57b 100644
--- a/wifi/java/android/net/wifi/WifiScanner.java
+++ b/wifi/java/android/net/wifi/WifiScanner.java
@@ -30,7 +30,9 @@
import android.util.Log;
import android.util.SparseArray;
+import com.android.internal.annotations.VisibleForTesting;
import com.android.internal.util.AsyncChannel;
+import com.android.internal.util.Preconditions;
import com.android.internal.util.Protocol;
import java.util.List;
@@ -78,6 +80,8 @@
public static final int REASON_INVALID_REQUEST = -3;
/** Invalid request */
public static final int REASON_NOT_AUTHORIZED = -4;
+ /** An outstanding request with the same listener hasn't finished yet. */
+ public static final int REASON_DUPLICATE_REQEUST = -5;
/** @hide */
public static final String GET_AVAILABLE_CHANNELS_EXTRA = "Channels";
@@ -464,8 +468,11 @@
* scans should also not share this object.
*/
public void startBackgroundScan(ScanSettings settings, ScanListener listener) {
+ Preconditions.checkNotNull(listener, "listener cannot be null");
+ int key = addListener(listener);
+ if (key == INVALID_KEY) return;
validateChannel();
- sAsyncChannel.sendMessage(CMD_START_BACKGROUND_SCAN, 0, putListener(listener), settings);
+ sAsyncChannel.sendMessage(CMD_START_BACKGROUND_SCAN, 0, key, settings);
}
/**
* stop an ongoing wifi scan
@@ -473,8 +480,11 @@
* #startBackgroundScan}
*/
public void stopBackgroundScan(ScanListener listener) {
+ Preconditions.checkNotNull(listener, "listener cannot be null");
+ int key = removeListener(listener);
+ if (key == INVALID_KEY) return;
validateChannel();
- sAsyncChannel.sendMessage(CMD_STOP_BACKGROUND_SCAN, 0, removeListener(listener));
+ sAsyncChannel.sendMessage(CMD_STOP_BACKGROUND_SCAN, 0, key);
}
/**
* reports currently available scan results on appropriate listeners
@@ -495,8 +505,11 @@
* scans should also not share this object.
*/
public void startScan(ScanSettings settings, ScanListener listener) {
+ Preconditions.checkNotNull(listener, "listener cannot be null");
+ int key = addListener(listener);
+ if (key == INVALID_KEY) return;
validateChannel();
- sAsyncChannel.sendMessage(CMD_START_SINGLE_SCAN, 0, putListener(listener), settings);
+ sAsyncChannel.sendMessage(CMD_START_SINGLE_SCAN, 0, key, settings);
}
/**
@@ -505,8 +518,11 @@
* @param listener
*/
public void stopScan(ScanListener listener) {
+ Preconditions.checkNotNull(listener, "listener cannot be null");
+ int key = removeListener(listener);
+ if (key == INVALID_KEY) return;
validateChannel();
- sAsyncChannel.sendMessage(CMD_STOP_SINGLE_SCAN, 0, removeListener(listener));
+ sAsyncChannel.sendMessage(CMD_STOP_SINGLE_SCAN, 0, key);
}
/** specifies information about an access point of interest */
@@ -638,8 +654,11 @@
* provided on {@link #stopTrackingWifiChange}
*/
public void startTrackingWifiChange(WifiChangeListener listener) {
+ Preconditions.checkNotNull(listener, "listener cannot be null");
+ int key = addListener(listener);
+ if (key == INVALID_KEY) return;
validateChannel();
- sAsyncChannel.sendMessage(CMD_START_TRACKING_CHANGE, 0, putListener(listener));
+ sAsyncChannel.sendMessage(CMD_START_TRACKING_CHANGE, 0, key);
}
/**
@@ -648,8 +667,10 @@
* #stopTrackingWifiChange}
*/
public void stopTrackingWifiChange(WifiChangeListener listener) {
+ int key = removeListener(listener);
+ if (key == INVALID_KEY) return;
validateChannel();
- sAsyncChannel.sendMessage(CMD_STOP_TRACKING_CHANGE, 0, removeListener(listener));
+ sAsyncChannel.sendMessage(CMD_STOP_TRACKING_CHANGE, 0, key);
}
/** @hide */
@@ -734,11 +755,14 @@
*/
public void startTrackingBssids(BssidInfo[] bssidInfos,
int apLostThreshold, BssidListener listener) {
+ Preconditions.checkNotNull(listener, "listener cannot be null");
+ int key = addListener(listener);
+ if (key == INVALID_KEY) return;
validateChannel();
HotlistSettings settings = new HotlistSettings();
settings.bssidInfos = bssidInfos;
settings.apLostThreshold = apLostThreshold;
- sAsyncChannel.sendMessage(CMD_SET_HOTLIST, 0, putListener(listener), settings);
+ sAsyncChannel.sendMessage(CMD_SET_HOTLIST, 0, key, settings);
}
/**
@@ -746,8 +770,11 @@
* @param listener same object provided in {@link #startTrackingBssids}
*/
public void stopTrackingBssids(BssidListener listener) {
+ Preconditions.checkNotNull(listener, "listener cannot be null");
+ int key = removeListener(listener);
+ if (key == INVALID_KEY) return;
validateChannel();
- sAsyncChannel.sendMessage(CMD_RESET_HOTLIST, 0, removeListener(listener));
+ sAsyncChannel.sendMessage(CMD_RESET_HOTLIST, 0, key);
}
@@ -816,7 +843,7 @@
private static final Object sThreadRefLock = new Object();
private static int sThreadRefCount;
- private static HandlerThread sHandlerThread;
+ private static Handler sInternalHandler;
/**
* Create a new WifiScanner instance.
@@ -828,12 +855,29 @@
* @hide
*/
public WifiScanner(Context context, IWifiScanner service) {
- mContext = context;
- mService = service;
- init();
+ this(context, service, null, true);
}
- private void init() {
+ /**
+ * Create a new WifiScanner instance.
+ *
+ * @param context The application context.
+ * @param service The IWifiScanner Binder interface
+ * @param looper Looper for running WifiScanner operations. If null, a handler thread will be
+ * created for running WifiScanner operations.
+ * @param waitForConnection If true, this will not return until a connection to Wifi Scanner
+ * service is established.
+ * @hide
+ */
+ @VisibleForTesting
+ public WifiScanner(Context context, IWifiScanner service, Looper looper,
+ boolean waitForConnection) {
+ mContext = context;
+ mService = service;
+ init(looper, waitForConnection);
+ }
+
+ private void init(Looper looper, boolean waitForConnection) {
synchronized (sThreadRefLock) {
if (++sThreadRefCount == 1) {
Messenger messenger = null;
@@ -850,17 +894,23 @@
return;
}
- sHandlerThread = new HandlerThread("WifiScanner");
sAsyncChannel = new AsyncChannel();
sConnected = new CountDownLatch(1);
- sHandlerThread.start();
- Handler handler = new ServiceHandler(sHandlerThread.getLooper());
- sAsyncChannel.connect(mContext, handler, messenger);
- try {
- sConnected.await();
- } catch (InterruptedException e) {
- Log.e(TAG, "interrupted wait at init");
+ if (looper == null) {
+ HandlerThread thread = new HandlerThread("WifiScanner");
+ thread.start();
+ sInternalHandler = new ServiceHandler(thread.getLooper());
+ } else {
+ sInternalHandler = new ServiceHandler(looper);
+ }
+ sAsyncChannel.connect(mContext, sInternalHandler, messenger);
+ if (waitForConnection) {
+ try {
+ sConnected.await();
+ } catch (InterruptedException e) {
+ Log.e(TAG, "interrupted wait at init");
+ }
}
}
}
@@ -871,6 +921,30 @@
"No permission to access and change wifi or a bad initialization");
}
+ // Add a listener into listener map. If the listener already exists, return INVALID_KEY and
+ // send an error message to internal handler; Otherwise add the listener to the listener map and
+ // return the key of the listener.
+ private int addListener(ActionListener listener) {
+ synchronized (sListenerMap) {
+ boolean keyExists = (getListenerKey(listener) != INVALID_KEY);
+ // Note we need to put the listener into listener map even if it's a duplicate as the
+ // internal handler will need the key to find the listener. In case of duplicates,
+ // removing duplicate key logic will be handled in internal handler.
+ int key = putListener(listener);
+ if (keyExists) {
+ if (DBG) Log.d(TAG, "listener key already exists");
+ OperationResult operationResult = new OperationResult(REASON_DUPLICATE_REQEUST,
+ "Outstanding request with same key not stopped yet");
+ Message message = Message.obtain(sInternalHandler, CMD_OP_FAILED, 0, key,
+ operationResult);
+ message.sendToTarget();
+ return INVALID_KEY;
+ } else {
+ return key;
+ }
+ }
+ }
+
private static int putListener(Object listener) {
if (listener == null) return INVALID_KEY;
int key;
@@ -914,7 +988,10 @@
private static int removeListener(Object listener) {
int key = getListenerKey(listener);
- if (key == INVALID_KEY) return key;
+ if (key == INVALID_KEY) {
+ Log.e(TAG, "listener cannot be found");
+ return key;
+ }
synchronized (sListenerMapLock) {
sListenerMap.remove(key);
return key;