Merge "Add Network.fromNetworkHandle()" into pi-dev

am: c0b767a937

Change-Id: I22e68ab29982690dee5b2c0c6e1fbd47df0b0326

core/java/android/net/Network.java

@@ -77,6 +77,11 @@ public class Network implements Parcelable {
             httpKeepAlive ? Integer.parseInt(System.getProperty("http.maxConnections", "5")) : 0;
     private static final long httpKeepAliveDurationMs =
             Long.parseLong(System.getProperty("http.keepAliveDuration", "300000"));  // 5 minutes.
+    // Value used to obfuscate network handle longs.
+    // The HANDLE_MAGIC value MUST be kept in sync with the corresponding
+    // value in the native/android/net.c NDK implementation.
+    private static final long HANDLE_MAGIC = 0xcafed00dL;
+    private static final int HANDLE_MAGIC_SIZE = 32;
 
     /**
      * @hide
@@ -334,6 +339,25 @@ public class Network implements Parcelable {
         }
     }
 
+    /**
+     * Returns a {@link Network} object given a handle returned from {@link #getNetworkHandle}.
+     *
+     * @param networkHandle a handle returned from {@link #getNetworkHandle}.
+     * @return A {@link Network} object derived from {@code networkHandle}.
+     */
+    public static Network fromNetworkHandle(long networkHandle) {
+        if (networkHandle == 0) {
+            throw new IllegalArgumentException(
+                    "Network.fromNetworkHandle refusing to instantiate NETID_UNSET Network.");
+        }
+        if ((networkHandle & ((1L << HANDLE_MAGIC_SIZE) - 1)) != HANDLE_MAGIC
+                || networkHandle < 0) {
+            throw new IllegalArgumentException(
+                    "Value passed to fromNetworkHandle() is not a network handle.");
+        }
+        return new Network((int) (networkHandle >> HANDLE_MAGIC_SIZE));
+    }
+
     /**
      * Returns a handle representing this {@code Network}, for use with the NDK API.
      */
@@ -356,14 +380,10 @@ public class Network implements Parcelable {
         // At some future date it may be desirable to realign the handle with
         // Multiple Provisioning Domains API recommendations, as made by the
         // IETF mif working group.
-        //
-        // The handleMagic value MUST be kept in sync with the corresponding
-        // value in the native/android/net.c NDK implementation.
         if (netId == 0) {
             return 0L;  // make this zero condition obvious for debugging
         }
-        final long handleMagic = 0xcafed00dL;
+        return (((long) netId) << HANDLE_MAGIC_SIZE) | HANDLE_MAGIC;
-        return (((long) netId) << 32) | handleMagic;
     }
 
     // implement the Parcelable interface