Merge "MidiDeviceServer: Fix race condition in setting device server's mDeviceInfo" into mnc-dev

media/java/android/media/midi/IMidiDeviceServer.aidl

@@ -31,4 +31,5 @@ interface IMidiDeviceServer
     void connectPorts(IBinder token, in ParcelFileDescriptor pfd, int outputPortNumber);
 
     MidiDeviceInfo getDeviceInfo();
+    void setDeviceInfo(in MidiDeviceInfo deviceInfo);
 }

media/java/android/media/midi/MidiDeviceServer.java

@@ -269,8 +269,20 @@ public final class MidiDeviceServer implements Closeable {
         public MidiDeviceInfo getDeviceInfo() {
             return mDeviceInfo;
         }
+
+        @Override
+        public void setDeviceInfo(MidiDeviceInfo deviceInfo) {
+            if (Binder.getCallingUid() != Process.SYSTEM_UID) {
+                throw new SecurityException("setDeviceInfo should only be called by MidiService");
+            }
+            if (mDeviceInfo != null) {
+                throw new IllegalStateException("setDeviceInfo should only be called once");
+            }
+            mDeviceInfo = deviceInfo;
+        }
     };
 
+    // Constructor for MidiManager.createDeviceServer()
     /* package */ MidiDeviceServer(IMidiManager midiManager, MidiReceiver[] inputPortReceivers,
             int numOutputPorts, Callback callback) {
         mMidiManager = midiManager;
@@ -292,6 +304,13 @@ public final class MidiDeviceServer implements Closeable {
         mGuard.open("close");
     }
 
+    // Constructor for MidiDeviceService.onCreate()
+    /* package */ MidiDeviceServer(IMidiManager midiManager, MidiReceiver[] inputPortReceivers,
+           MidiDeviceInfo deviceInfo, Callback callback) {
+        this(midiManager, inputPortReceivers, deviceInfo.getOutputPortCount(), callback);
+        mDeviceInfo = deviceInfo;
+    }
+
     /* package */ IMidiDeviceServer getBinderInterface() {
         return mServer;
     }
@@ -300,13 +319,6 @@ public final class MidiDeviceServer implements Closeable {
         return mServer.asBinder();
     }
 
-    /* package */ void setDeviceInfo(MidiDeviceInfo deviceInfo) {
-        if (mDeviceInfo != null) {
-            throw new IllegalStateException("setDeviceInfo should only be called once");
-        }
-        mDeviceInfo = deviceInfo;
-    }
-
     private void updateDeviceStatus() {
         // clear calling identity, since we may be in a Binder call from one of our clients
         long identityToken = Binder.clearCallingIdentity();

media/java/android/media/midi/MidiDeviceService.java

@@ -83,9 +83,7 @@ abstract public class MidiDeviceService extends Service {
             if (inputPortReceivers == null) {
                 inputPortReceivers = new MidiReceiver[0];
             }
-            server = new MidiDeviceServer(mMidiManager, inputPortReceivers,
+            server = new MidiDeviceServer(mMidiManager, inputPortReceivers, deviceInfo, mCallback);
-                    deviceInfo.getOutputPortCount(), mCallback);
-            server.setDeviceInfo(deviceInfo);
         } catch (RemoteException e) {
             Log.e(TAG, "RemoteException in IMidiManager.getServiceDeviceInfo");
             server = null;

media/java/android/media/midi/MidiManager.java

@@ -318,7 +318,6 @@ public final class MidiManager {
                 Log.e(TAG, "registerVirtualDevice failed");
                 return null;
             }
-            server.setDeviceInfo(deviceInfo);
             return server;
         } catch (RemoteException e) {
             Log.e(TAG, "RemoteException in createVirtualDevice");

services/midi/java/com/android/server/midi/MidiService.java

@@ -741,6 +741,15 @@ public class MidiService extends IMidiManager.Stub {
         MidiDeviceInfo deviceInfo = new MidiDeviceInfo(type, id, numInputPorts, numOutputPorts,
                 inputPortNames, outputPortNames, properties, isPrivate);
 
+        if (server != null) {
+            try {
+                server.setDeviceInfo(deviceInfo);
+            } catch (RemoteException e) {
+                Log.e(TAG, "RemoteException in setDeviceInfo()");
+                return null;
+            }
+        }
+
         Device device = null;
         BluetoothDevice bluetoothDevice = null;
         if (type == MidiDeviceInfo.TYPE_BLUETOOTH) {