1 files changed, 11 insertions, 0 deletions

diff --git a/linden/indra/llmessage/llcircuit.cpp b/linden/indra/llmessage/llcircuit.cpp
index 12a1520..7b2f241 100644
--- a/linden/indra/llmessage/llcircuit.cpp
+++ b/linden/indra/llmessage/llcircuit.cpp
@@ -60,6 +60,7 @@
 #include "llrand.h"
 #include "llstl.h"
 #include "lltransfermanager.h"
+#include "llmodularmath.h"
 
 const F32 PING_INTERVAL = 5.f; // seconds
 const S32 PING_START_BLOCK = 3;         // How many pings behind we have to be to consider ourself blocked.
@@ -676,6 +677,8 @@ void LLCircuitData::checkPacketInID(TPACKETID id, BOOL receive_resent)
                 mPacketsIn++;
                 setPacketInID((id + 1) % LL_MAX_OUT_PACKET_ID);
 
+        mLastPacketGap = 0;
+        mOutOfOrderRate.count(0);
                 return;
         }
 
@@ -683,6 +686,7 @@ void LLCircuitData::checkPacketInID(TPACKETID id, BOOL receive_resent)
 
 
         // now, check to see if we've got a gap
+    U32 gap = 0;
         if ((mPacketsInID == id))
         {
                 // nope! bump and wrap the counter, then return
@@ -704,6 +708,11 @@ void LLCircuitData::checkPacketInID(TPACKETID id, BOOL receive_resent)
                 // otherwise, walk from mCurrentCircuit->mPacketsInID to id with wrapping, adding the values to the map
                 // and setting mPacketsInID to id + 1 % LL_MAX_OUT_PACKET_ID
 
+        // babbage: all operands in expression are unsigned, so modular 
+                // arithmetic will always find correct gap, regardless of wrap arounds.
+                const U8 width = 24;
+                gap = LLModularMath::subtract<width>(mPacketsInID, id);
+
                 if (mPotentialLostPackets.find(id) != mPotentialLostPackets.end())
                 {
                         if(gMessageSystem->mVerboseLog)
@@ -765,6 +774,8 @@ void LLCircuitData::checkPacketInID(TPACKETID id, BOOL receive_resent)
 
                 }
         }
+    mOutOfOrderRate.count(gap);
+    mLastPacketGap = gap;
 }