commit f37c91b2ad585acf86f843efc275a063615b0f3b
author Sahin Caliskan <sahinc@google.com> Tue Nov 01 11:43:38 2016 -0700
committer Sahin Caliskan <sahinc@google.com> Wed Nov 02 11:28:53 2016 -0700
tree 418a6569bd991a6544da589dc0ceae0c744b43e2
parent ef3bdb5f6eed90b525c3d771079ac75aebac7ba9

31613454 Prevent setting up network twice for receiving MMS

* This change adds five seconds of embrace time before releasing an
MMS network. This allows MMS received acknowledgement messages to
be sent as the same network the MMS was downloaded from.

Test: Tested manually

Change-Id: Ieb1c56e2cda8d8b206b65d80049536736afe6737
Fixes: 31613454

src/com/android/mms/service/MmsNetworkManager.java

diff --git a/src/com/android/mms/service/MmsNetworkManager.java b/src/com/android/mms/service/MmsNetworkManager.java
index c2e2f6a..a37d31c 100644
--- a/src/com/android/mms/service/MmsNetworkManager.java
+++ b/src/com/android/mms/service/MmsNetworkManager.java
@@ -22,6 +22,8 @@
 import android.net.NetworkCapabilities;
 import android.net.NetworkInfo;
 import android.net.NetworkRequest;
+import android.os.Handler;
+import android.os.Looper;
 import android.os.SystemClock;
 
 import com.android.mms.service.exception.MmsNetworkException;
@@ -37,6 +39,9 @@
     // to make sure we don't bail prematurely
     private static final int NETWORK_ACQUIRE_TIMEOUT_MILLIS =
             NETWORK_REQUEST_TIMEOUT_MILLIS + (5 * 1000);
+    // Waiting time used before releasing a network prematurely. This allows the MMS download
+    // acknowledgement messages to be sent using the same network that was used to download the data
+    private static final int NETWORK_RELEASE_TIMEOUT_MILLIS = 5 * 1000;
 
     private final Context mContext;
 
@@ -57,6 +62,12 @@
     // The MMS HTTP client for this network
     private MmsHttpClient mMmsHttpClient;
 
+    // The handler used for delayed release of the network
+    private final Handler mReleaseHandler;
+
+    // The task that does the delayed releasing of the network.
+    private final Runnable mNetworkReleaseTask;
+
     // The SIM ID which we use to connect
     private final int mSubId;
 
@@ -103,11 +114,23 @@
         mConnectivityManager = null;
         mMmsHttpClient = null;
         mSubId = subId;
+        mReleaseHandler = new Handler(Looper.getMainLooper());
         mNetworkRequest = new NetworkRequest.Builder()
                 .addTransportType(NetworkCapabilities.TRANSPORT_CELLULAR)
                 .addCapability(NetworkCapabilities.NET_CAPABILITY_MMS)
                 .setNetworkSpecifier(Integer.toString(mSubId))
                 .build();
+
+        mNetworkReleaseTask = new Runnable() {
+            @Override
+            public void run() {
+                synchronized (this) {
+                    if (mMmsRequestCount < 1) {
+                        releaseRequestLocked(mNetworkCallback);
+                    }
+                }
+            }
+        };
     }
 
     /**
@@ -118,6 +141,8 @@
      */
     public void acquireNetwork(final String requestId) throws MmsNetworkException {
         synchronized (this) {
+            // Since we are acquiring the network, remove the network release task if exists.
+            mReleaseHandler.removeCallbacks(mNetworkReleaseTask);
             mMmsRequestCount += 1;
             if (mNetwork != null) {
                 // Already available
@@ -155,14 +180,25 @@
      * Release the MMS network when nobody is holding on to it.
      *
      * @param requestId request ID for logging
+     * @param shouldDelayRelease whether the release should be delayed for 5 seconds, the regular
+     *                           use case is to delay this for DownloadRequests to use the network
+     *                           for sending an acknowledgement on the same network
      */
-    public void releaseNetwork(final String requestId) {
+    public void releaseNetwork(final String requestId, final boolean shouldDelayRelease) {
         synchronized (this) {
             if (mMmsRequestCount > 0) {
                 mMmsRequestCount -= 1;
                 LogUtil.d(requestId, "MmsNetworkManager: release, count=" + mMmsRequestCount);
                 if (mMmsRequestCount < 1) {
-                    releaseRequestLocked(mNetworkCallback);
+                    if (shouldDelayRelease) {
+                        // remove previously posted task and post a delayed task on the release
+                        // handler to release the network
+                        mReleaseHandler.removeCallbacks(mNetworkReleaseTask);
+                        mReleaseHandler.postDelayed(mNetworkReleaseTask,
+                                NETWORK_RELEASE_TIMEOUT_MILLIS);
+                    } else {
+                        releaseRequestLocked(mNetworkCallback);
+                    }
                 }
             }
         }

src/com/android/mms/service/MmsRequest.java

diff --git a/src/com/android/mms/service/MmsRequest.java b/src/com/android/mms/service/MmsRequest.java
index 4eeac08..ec8b334 100644
--- a/src/com/android/mms/service/MmsRequest.java
+++ b/src/com/android/mms/service/MmsRequest.java
@@ -173,7 +173,7 @@
                         // Success
                         break;
                     } finally {
-                        networkManager.releaseNetwork(requestId);
+                        networkManager.releaseNetwork(requestId, this instanceof DownloadRequest);
                     }
                 } catch (ApnException e) {
                     LogUtil.e(requestId, "APN failure", e);