From 30ecc1c9f6d7c26ec8600e53e1f89c4430ea5982 Mon Sep 17 00:00:00 2001
From: Hans-Christoph Steiner <hans@eds.org>
Date: Mon, 19 May 2014 21:57:39 -0400
Subject: [PATCH] use MulticastLock for better Bonjour/mDNS performance

Multicast transmission is subject to heavy power management on Android,
because it apparently can be a battery drain.  mDNS/Bonjour is based
entirely on multicast, so in order to have good Bonjour performance, there
needs to be good multicast performance.  MulticastLock provides that.

fixes #3381 https://dev.guardianproject.info/issues/3381
---
 AndroidManifest.xml                       | 1 +
 src/org/fdroid/fdroid/net/MDnsHelper.java | 8 ++++++++
 2 files changed, 9 insertions(+)

diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 13d8b590d..0c1ecc827 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -34,6 +34,7 @@
     <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
     <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
+    <uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE" />
     <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
     <uses-permission android:name="android.permission.BLUETOOTH" />
     <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
diff --git a/src/org/fdroid/fdroid/net/MDnsHelper.java b/src/org/fdroid/fdroid/net/MDnsHelper.java
index 48e2bc853..30a1305a6 100644
--- a/src/org/fdroid/fdroid/net/MDnsHelper.java
+++ b/src/org/fdroid/fdroid/net/MDnsHelper.java
@@ -3,6 +3,8 @@ package org.fdroid.fdroid.net;
 
 import android.app.Activity;
 import android.content.Context;
+import android.net.wifi.WifiManager;
+import android.net.wifi.WifiManager.MulticastLock;
 import android.os.AsyncTask;
 import android.os.Handler;
 import android.os.Looper;
@@ -32,10 +34,14 @@ public class MDnsHelper implements ServiceListener {
     final RepoScanListAdapter mAdapter;
 
     private JmDNS mJmdns;
+    private MulticastLock mMulticastLock;
 
     public MDnsHelper(Activity activity, final RepoScanListAdapter adapter) {
         mActivity = activity;
         mAdapter = adapter;
+        WifiManager wm = (WifiManager) activity.getSystemService(Context.WIFI_SERVICE);
+        mMulticastLock = wm.createMulticastLock(activity.getPackageName());
+        mMulticastLock.setReferenceCounted(false);
     }
 
     @Override
@@ -75,6 +81,7 @@ public class MDnsHelper implements ServiceListener {
     }
 
     public void discoverServices() {
+        mMulticastLock.acquire();
         new AsyncTask<Void, Void, Void>() {
 
             @Override
@@ -98,6 +105,7 @@ public class MDnsHelper implements ServiceListener {
     }
 
     public void stopDiscovery() {
+        mMulticastLock.release();
         if (mJmdns == null)
             return;
         mJmdns.removeServiceListener(HTTP_SERVICE_TYPE, MDnsHelper.this);