From e0d8349d71be2c911d0b073a433caee27d362b54 Mon Sep 17 00:00:00 2001
From: Tommaso Pecorella <tommaso.pecorella@unifi.it>
Date: Sun, 6 Apr 2014 12:36:51 +0200
Subject: [PATCH] Possible bug fix and sequence number as SequenceNumber8

---
 src/lr-wpan/model/lr-wpan-mac.cc    | 16 ++++++----------
 src/lr-wpan/model/lr-wpan-mac.h     |  2 +-
 src/network/utils/sequence-number.h |  1 +
 3 files changed, 8 insertions(+), 11 deletions(-)

diff --git a/src/lr-wpan/model/lr-wpan-mac.cc b/src/lr-wpan/model/lr-wpan-mac.cc
index 51ffcecc4..9fc1dc3b8 100644
--- a/src/lr-wpan/model/lr-wpan-mac.cc
+++ b/src/lr-wpan/model/lr-wpan-mac.cc
@@ -105,7 +105,7 @@ LrWpanMac::LrWpanMac ()
 
   UniformVariable uniformVar;
   uniformVar = UniformVariable (0, 255);
-  m_macDsn = SequenceNumber16 (uniformVar.GetValue ());
+  m_macDsn = SequenceNumber8 (uniformVar.GetValue ());
   m_shortAddress = Mac16Address ("00:00");
 }
 
@@ -215,12 +215,8 @@ LrWpanMac::McpsDataRequest (McpsDataRequestParams params, Ptr<Packet> p)
   //       The current tx drop trace is not suitable, because packets dropped using this trace carry the mac header
   //       and footer, while packets being dropped here do not have them.
 
-  LrWpanMacHeader macHdr (LrWpanMacHeader::LRWPAN_MAC_DATA, (uint8_t)m_macDsn.GetValue ());
+  LrWpanMacHeader macHdr (LrWpanMacHeader::LRWPAN_MAC_DATA, m_macDsn.GetValue ());
   m_macDsn++;
-  if (m_macDsn > SequenceNumber16 (255))
-    {
-      m_macDsn = m_macDsn - SequenceNumber16 (255);
-    }
 
   if (p->GetSize () > LrWpanPhy::aMaxPhyPacketSize - aMinMPDUOverhead)
     {
@@ -735,10 +731,6 @@ LrWpanMac::PdDataConfirm (LrWpanPhyEnumeration status)
 
   NS_LOG_FUNCTION (this << status << m_txQueue.size ());
 
-  // \todo: Temporary assert. This is a bug.
-  NS_ASSERT_MSG (m_txQueue.size () > 0, "TxQsize = 0");
-  TxQueueElement *txQElement = m_txQueue.front ();
-
   LrWpanMacHeader macHdr;
   m_txPkt->PeekHeader (macHdr);
   if (status == IEEE_802_15_4_PHY_SUCCESS)
@@ -764,6 +756,8 @@ LrWpanMac::PdDataConfirm (LrWpanPhyEnumeration status)
               if (!m_mcpsDataConfirmCallback.IsNull ())
                 {
                   McpsDataConfirmParams confirmParams;
+                  NS_ASSERT_MSG (m_txQueue.size () > 0, "TxQsize = 0");
+                  TxQueueElement *txQElement = m_txQueue.front ();
                   confirmParams.m_msduHandle = txQElement->txQMsduHandle;
                   confirmParams.m_status = IEEE_802_15_4_SUCCESS;
                   m_mcpsDataConfirmCallback (confirmParams);
@@ -782,6 +776,8 @@ LrWpanMac::PdDataConfirm (LrWpanPhyEnumeration status)
 
       if (!macHdr.IsAcknowledgment ())
         {
+          NS_ASSERT_MSG (m_txQueue.size () > 0, "TxQsize = 0");
+          TxQueueElement *txQElement = m_txQueue.front ();
           m_macTxDropTrace (txQElement->txQPkt);
           if (!m_mcpsDataConfirmCallback.IsNull ())
             {
diff --git a/src/lr-wpan/model/lr-wpan-mac.h b/src/lr-wpan/model/lr-wpan-mac.h
index 59ab180b5..a6ed7f07a 100644
--- a/src/lr-wpan/model/lr-wpan-mac.h
+++ b/src/lr-wpan/model/lr-wpan-mac.h
@@ -286,7 +286,7 @@ public:
   uint64_t m_macSuperframeOrder;        // 0..14 and 15 means superframe shall not remain active after beacon
   bool m_macPromiscuousMode;            // Indicates if MAC sublayer is in receive all mode. True mean accept all frames from PHY.
   uint16_t m_macPanId;                  // 16bits id of PAN on which this device is operating. 0xffff means not asscoiated
-  SequenceNumber16 m_macDsn;            // Seq num added to transmitted data or MAC command frame 00-ff
+  SequenceNumber8 m_macDsn;             // Seq num added to transmitted data or MAC command frame 00-ff
   uint8_t m_macMaxFrameRetries;         // The maximum number of retries allowed after a transmission failure
   
   uint64_t GetMacAckWaitDuration (void) const;
diff --git a/src/network/utils/sequence-number.h b/src/network/utils/sequence-number.h
index 57cc879f7..8a569a7c9 100644
--- a/src/network/utils/sequence-number.h
+++ b/src/network/utils/sequence-number.h
@@ -469,6 +469,7 @@ std::istream & operator >> (std::istream &is, const SequenceNumber<NUMERIC_TYPE,
 typedef SequenceNumber<uint32_t, int32_t> SequenceNumber32;
 /// 16 bit Sequence number
 typedef SequenceNumber<uint16_t, int16_t> SequenceNumber16;
+typedef SequenceNumber<uint8_t, int8_t> SequenceNumber8;
 
 } // namespace ns3