Revert "Merge "Remove CONNECTIVITY_CHANGE_DELAY and friends." into lmp-mr1-dev"

This is the revert of ag/572619.

This reverts commit b5ae87a8d0, reversing
changes made to 32b61ab28f54e5b00f472b2166f9b1100375e4ff.

Bug: 18609055
Bug: 17769720
Change-Id: I122eba200f2071d4e5777ec34c1d04fb567345a8

core/java/android/net/ConnectivityManager.java

@@ -100,7 +100,7 @@ public class ConnectivityManager {
 
     /**
      * Identical to {@link #CONNECTIVITY_ACTION} broadcast, but sent without any
-     * historic {@link Settings.Global#CONNECTIVITY_CHANGE_DELAY}.
+     * applicable {@link Settings.Global#CONNECTIVITY_CHANGE_DELAY}.
      *
      * @hide
      */
@@ -427,6 +427,18 @@ public class ConnectivityManager {
     @Deprecated
     public static final int DEFAULT_NETWORK_PREFERENCE = TYPE_WIFI;
 
+    /**
+     * Default value for {@link Settings.Global#CONNECTIVITY_CHANGE_DELAY} in
+     * milliseconds.  This was introduced because IPv6 routes seem to take a
+     * moment to settle - trying network activity before the routes are adjusted
+     * can lead to packets using the wrong interface or having the wrong IP address.
+     * This delay is a bit crude, but in the future hopefully we will have kernel
+     * notifications letting us know when it's safe to use the new network.
+     *
+     * @hide
+     */
+    public static final int CONNECTIVITY_CHANGE_DELAY_DEFAULT = 3000;
+
     /**
      * @hide
      */

services/core/java/com/android/server/ConnectivityService.java

@@ -797,6 +797,17 @@ public class ConnectivityService extends IConnectivityManager.Stub
         throw new IllegalStateException("No free netIds");
     }
 
+    private int getConnectivityChangeDelay() {
+        final ContentResolver cr = mContext.getContentResolver();
+
+        /** Check system properties for the default value then use secure settings value, if any. */
+        int defaultDelay = SystemProperties.getInt(
+                "conn." + Settings.Global.CONNECTIVITY_CHANGE_DELAY,
+                ConnectivityManager.CONNECTIVITY_CHANGE_DELAY_DEFAULT);
+        return Settings.Global.getInt(cr, Settings.Global.CONNECTIVITY_CHANGE_DELAY,
+                defaultDelay);
+    }
+
     private boolean teardown(NetworkStateTracker netTracker) {
         if (netTracker.teardown()) {
             netTracker.setTeardownRequested(true);
@@ -1468,6 +1479,11 @@ public class ConnectivityService extends IConnectivityManager.Stub
         sendGeneralBroadcast(info, CONNECTIVITY_ACTION);
     }
 
+    private void sendConnectedBroadcastDelayed(NetworkInfo info, int delayMs) {
+        sendGeneralBroadcast(info, CONNECTIVITY_ACTION_IMMEDIATE);
+        sendGeneralBroadcastDelayed(info, CONNECTIVITY_ACTION, delayMs);
+    }
+
     private void sendInetConditionBroadcast(NetworkInfo info) {
         sendGeneralBroadcast(info, ConnectivityManager.INET_CONDITION_ACTION);
     }
@@ -1499,6 +1515,10 @@ public class ConnectivityService extends IConnectivityManager.Stub
         sendStickyBroadcast(makeGeneralIntent(info, bcastType));
     }
 
+    private void sendGeneralBroadcastDelayed(NetworkInfo info, String bcastType, int delayMs) {
+        sendStickyBroadcastDelayed(makeGeneralIntent(info, bcastType), delayMs);
+    }
+
     private void sendDataActivityBroadcast(int deviceType, boolean active, long tsNanos) {
         Intent intent = new Intent(ConnectivityManager.ACTION_DATA_ACTIVITY_CHANGE);
         intent.putExtra(ConnectivityManager.EXTRA_DEVICE_TYPE, deviceType);
@@ -1532,6 +1552,19 @@ public class ConnectivityService extends IConnectivityManager.Stub
         }
     }
 
+    private void sendStickyBroadcastDelayed(Intent intent, int delayMs) {
+        if (delayMs <= 0) {
+            sendStickyBroadcast(intent);
+        } else {
+            if (VDBG) {
+                log("sendStickyBroadcastDelayed: delayMs=" + delayMs + ", action="
+                        + intent.getAction());
+            }
+            mHandler.sendMessageDelayed(mHandler.obtainMessage(
+                    EVENT_SEND_STICKY_BROADCAST_INTENT, intent), delayMs);
+        }
+    }
+
     void systemReady() {
         // start network sampling ..
         Intent intent = new Intent(ACTION_PKT_CNT_SAMPLE_INTERVAL_ELAPSED);
@@ -4268,7 +4301,7 @@ public class ConnectivityService extends IConnectivityManager.Stub
         info.setType(type);
         if (connected) {
             info.setDetailedState(DetailedState.CONNECTED, null, info.getExtraInfo());
-            sendConnectedBroadcast(info);
+            sendConnectedBroadcastDelayed(info, getConnectivityChangeDelay());
         } else {
             info.setDetailedState(DetailedState.DISCONNECTED, null, info.getExtraInfo());
             Intent intent = new Intent(ConnectivityManager.CONNECTIVITY_ACTION);
@@ -4299,9 +4332,10 @@ public class ConnectivityService extends IConnectivityManager.Stub
             final Intent immediateIntent = new Intent(intent);
             immediateIntent.setAction(CONNECTIVITY_ACTION_IMMEDIATE);
             sendStickyBroadcast(immediateIntent);
-            sendStickyBroadcast(intent);
+            sendStickyBroadcastDelayed(intent, getConnectivityChangeDelay());
             if (newDefaultAgent != null) {
-                sendConnectedBroadcast(newDefaultAgent.networkInfo);
+                sendConnectedBroadcastDelayed(newDefaultAgent.networkInfo,
+                getConnectivityChangeDelay());
             }
         }
     }