Fix lease duration handling

Convert lease time in seconds to long before alarm
set up and add sanity check

Change-Id: I99524c97d9a643ffa8234d016d0e819a284977a1

1 files changed, 18 insertions, 7 deletions

diff --git a/core/java/android/net/DhcpStateMachine.java b/core/java/android/net/DhcpStateMachine.java
index f5cf14b..e2230c9 100644
--- a/core/java/android/net/DhcpStateMachine.java
+++ b/core/java/android/net/DhcpStateMachine.java
@@ -66,6 +66,9 @@ public class DhcpStateMachine extends HierarchicalStateMachine {
     private static final int DHCP_RENEW = 0;
     private static final String ACTION_DHCP_RENEW = "android.net.wifi.DHCP_RENEW";
 
+    //Used for sanity check on setting up renewal
+    private static final int MIN_RENEWAL_TIME_SECS = 5 * 60;  // 5 minutes
+
     private enum DhcpAction {
         START,
         RENEW
@@ -331,13 +334,21 @@ public class DhcpStateMachine extends HierarchicalStateMachine {
 
         if (success) {
             Log.d(TAG, "DHCP succeeded on " + mInterfaceName);
-            //Do it a bit earlier than half the lease duration time
-            //to beat the native DHCP client and avoid extra packets
-            //48% for one hour lease time = 29 minutes
-            mAlarmManager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP,
-                    SystemClock.elapsedRealtime() +
-                    dhcpInfoInternal.leaseDuration * 480, //in milliseconds
-                    mDhcpRenewalIntent);
+           long leaseDuration = dhcpInfoInternal.leaseDuration; //int to long conversion
+
+           //Sanity check for renewal
+           //TODO: would be good to notify the user that his network configuration is
+           //bad and that the device cannot renew below MIN_RENEWAL_TIME_SECS
+           if (leaseDuration < MIN_RENEWAL_TIME_SECS) {
+               leaseDuration = MIN_RENEWAL_TIME_SECS;
+           }
+           //Do it a bit earlier than half the lease duration time
+           //to beat the native DHCP client and avoid extra packets
+           //48% for one hour lease time = 29 minutes
+           mAlarmManager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP,
+                   SystemClock.elapsedRealtime() +
+                   leaseDuration * 480, //in milliseconds
+                   mDhcpRenewalIntent);
 
             mController.obtainMessage(CMD_POST_DHCP_ACTION, DHCP_SUCCESS, 0, dhcpInfoInternal)
                 .sendToTarget();