Copy all mutable state before sending to clients.

This resolves an issue with ConcurrentModificationException
or inconsistent data being perceived by clients.

Fixed an NPE in the WifiP2pDeviceList copy constructor.

Bug: 7133752
Change-Id: I37a4d004f7b1ca21d490f131039d81695db2ba42

Author: Jeff Brown

wifi/java/android/net/wifi/p2p/WifiP2pDeviceList.java

@@ -35,10 +35,9 @@
  */
 public class WifiP2pDeviceList implements Parcelable {
 
-    private HashMap<String, WifiP2pDevice> mDevices;
+    private final HashMap<String, WifiP2pDevice> mDevices = new HashMap<String, WifiP2pDevice>();
 
     public WifiP2pDeviceList() {
-        mDevices = new HashMap<String, WifiP2pDevice>();
     }
 
     /** copy constructor */
@@ -52,7 +51,6 @@ public WifiP2pDeviceList(WifiP2pDeviceList source) {
 
     /** @hide */
     public WifiP2pDeviceList(ArrayList<WifiP2pDevice> devices) {
-        mDevices = new HashMap<String, WifiP2pDevice>();
         for (WifiP2pDevice device : devices) {
             if (device.deviceAddress != null) {
                 mDevices.put(device.deviceAddress, device);

wifi/java/android/net/wifi/p2p/WifiP2pGroupList.java

@@ -16,6 +16,7 @@
 package android.net.wifi.p2p;
 
 import java.util.Collection;
+import java.util.Map;
 
 import android.os.Parcel;
 import android.os.Parcelable;
@@ -32,19 +33,20 @@ public class WifiP2pGroupList implements Parcelable {
 
     private static final int CREDENTIAL_MAX_NUM             =   32;
 
-    private LruCache<Integer, WifiP2pGroup> mGroups;
-    private GroupDeleteListener mListener;
+    private final LruCache<Integer, WifiP2pGroup> mGroups;
+    private final GroupDeleteListener mListener;
+
     private boolean isClearCalled = false;
 
     public interface GroupDeleteListener {
         public void onDeleteGroup(int netId);
     }
 
     WifiP2pGroupList() {
-        this(null);
+        this(null, null);
     }
 
-    WifiP2pGroupList(GroupDeleteListener listener) {
+    WifiP2pGroupList(WifiP2pGroupList source, GroupDeleteListener listener) {
         mListener = listener;
         mGroups = new LruCache<Integer, WifiP2pGroup>(CREDENTIAL_MAX_NUM) {
             @Override
@@ -55,6 +57,12 @@ protected void entryRemoved(boolean evicted, Integer netId,
                 }
             }
         };
+
+        if (source != null) {
+            for (Map.Entry<Integer, WifiP2pGroup> item : source.mGroups.snapshot().entrySet()) {
+                mGroups.put(item.getKey(), item.getValue());
+            }
+        }
     }
 
     /**

wifi/java/android/net/wifi/p2p/WifiP2pService.java

@@ -359,8 +359,8 @@ private class P2pStateMachine extends StateMachine {
         private WifiNative mWifiNative = new WifiNative(mInterface);
         private WifiMonitor mWifiMonitor = new WifiMonitor(this, mWifiNative);
 
-        private WifiP2pDeviceList mPeers = new WifiP2pDeviceList();
-        private WifiP2pGroupList mGroups = new WifiP2pGroupList(
+        private final WifiP2pDeviceList mPeers = new WifiP2pDeviceList();
+        private final WifiP2pGroupList mGroups = new WifiP2pGroupList(null,
                 new GroupDeleteListener() {
             @Override
             public void onDeleteGroup(int netId) {
@@ -370,7 +370,7 @@ public void onDeleteGroup(int netId) {
                 sendP2pPersistentGroupsChangedBroadcast();
             }
         });
-        private WifiP2pInfo mWifiP2pInfo = new WifiP2pInfo();
+        private final WifiP2pInfo mWifiP2pInfo = new WifiP2pInfo();
         private WifiP2pGroup mGroup;
 
         // Saved WifiP2pConfig for a peer connection
@@ -501,17 +501,20 @@ public boolean processMessage(Message message) {
                             WifiP2pManager.BUSY);
                     break;
                 case WifiP2pManager.REQUEST_PEERS:
-                    replyToMessage(message, WifiP2pManager.RESPONSE_PEERS, mPeers);
+                    replyToMessage(message, WifiP2pManager.RESPONSE_PEERS,
+                            new WifiP2pDeviceList(mPeers));
                     break;
                 case WifiP2pManager.REQUEST_CONNECTION_INFO:
-                    replyToMessage(message, WifiP2pManager.RESPONSE_CONNECTION_INFO, mWifiP2pInfo);
+                    replyToMessage(message, WifiP2pManager.RESPONSE_CONNECTION_INFO,
+                            new WifiP2pInfo(mWifiP2pInfo));
                     break;
                 case WifiP2pManager.REQUEST_GROUP_INFO:
-                    replyToMessage(message, WifiP2pManager.RESPONSE_GROUP_INFO, mGroup);
+                    replyToMessage(message, WifiP2pManager.RESPONSE_GROUP_INFO,
+                            mGroup != null ? new WifiP2pGroup(mGroup) : null);
                     break;
                 case WifiP2pManager.REQUEST_PERSISTENT_GROUP_INFO:
                     replyToMessage(message, WifiP2pManager.RESPONSE_PERSISTENT_GROUP_INFO,
-                            mGroups);
+                            new WifiP2pGroupList(mGroups, null));
                     break;
                 case WifiP2pManager.SET_DIALOG_LISTENER:
                     String appPkgName = (String)message.getData().getString(