[AWARE] Fix race condition of Aware state machine & HAL

The Wi-Fi Aware HAL was started before the Aware state machine
was ready. In case where the HAL was able to obtain a handle on
the NAN interface it would attempt to enable Aware through the
state machine - resulting in an NPE.

Added an explicit start method to the Aware HAL which is called
in order.

Bug: 37613363
Test: unit tests and integration (sl4a) test
Change-Id: I66698bd926ca5d4bdb19b3025ed2f26c61028d21

3 files changed, 4 insertions, 4 deletions

diff --git a/service/java/com/android/server/wifi/aware/WifiAwareNativeManager.java b/service/java/com/android/server/wifi/aware/WifiAwareNativeManager.java
index 22f13851f..f1945808f 100644
--- a/service/java/com/android/server/wifi/aware/WifiAwareNativeManager.java
+++ b/service/java/com/android/server/wifi/aware/WifiAwareNativeManager.java
@@ -53,6 +53,9 @@ class WifiAwareNativeManager {
         mWifiAwareStateManager = awareStateManager;
         mHalDeviceManager = halDeviceManager;
         mWifiAwareNativeCallback = wifiAwareNativeCallback;
+    }
+
+    public void start() {
         mHalDeviceManager.registerStatusListener(
                 new HalDeviceManager.ManagerStatusListener() {
                     @Override
diff --git a/service/java/com/android/server/wifi/aware/WifiAwareService.java b/service/java/com/android/server/wifi/aware/WifiAwareService.java
index 75efa0296..bd8156e17 100644
--- a/service/java/com/android/server/wifi/aware/WifiAwareService.java
+++ b/service/java/com/android/server/wifi/aware/WifiAwareService.java
@@ -65,6 +65,7 @@ public final class WifiAwareService extends SystemService {
 
             HandlerThread awareHandlerThread = wifiInjector.getWifiAwareHandlerThread();
             mImpl.start(awareHandlerThread, wifiAwareStateManager);
+            wifiAwareNativeManager.start();
         } else if (phase == SystemService.PHASE_BOOT_COMPLETED) {
             mImpl.startLate();
         }
diff --git a/service/java/com/android/server/wifi/aware/WifiAwareStateManager.java b/service/java/com/android/server/wifi/aware/WifiAwareStateManager.java
index 1d00d162d..a35c786ee 100644
--- a/service/java/com/android/server/wifi/aware/WifiAwareStateManager.java
+++ b/service/java/com/android/server/wifi/aware/WifiAwareStateManager.java
@@ -391,10 +391,6 @@ public class WifiAwareStateManager {
      * only happens when a connection is created.
      */
     public void enableUsage() {
-        if (mSm == null) {
-            Log.e(TAG, "enableUsage: race condition - called while mSm null!");
-            return;
-        }
         Message msg = mSm.obtainMessage(MESSAGE_TYPE_COMMAND);
         msg.arg1 = COMMAND_TYPE_ENABLE_USAGE;
         mSm.sendMessage(msg);