Replace src/csma usage of RandomVariable with RandomVariableStream

src/csma/helper/csma-helper.cc

@@ -281,6 +281,23 @@ CsmaHelper::Install (const NodeContainer &c, std::string channelName) const
   return Install (c, channel);
 }
 
+int64_t
+CsmaHelper::AssignStreams (NetDeviceContainer c, int64_t stream)
+{
+  int64_t currentStream = stream;
+  Ptr<NetDevice> netDevice;
+  for (NetDeviceContainer::Iterator i = c.Begin (); i != c.End (); ++i)
+    {
+      netDevice = (*i);
+      Ptr<CsmaNetDevice> csma = DynamicCast<CsmaNetDevice> (netDevice);
+      if (csma)
+        {
+          currentStream += csma->AssignStreams (currentStream);
+        }
+    }
+  return (currentStream - stream);
+}
+
 Ptr<NetDevice>
 CsmaHelper::InstallPriv (Ptr<Node> node, Ptr<CsmaChannel> channel) const
 {

src/csma/helper/csma-helper.h

@@ -192,6 +192,19 @@ public:
    */
   NetDeviceContainer Install (const NodeContainer &c, std::string channelName) const;
 
+  /**
+  * Assign a fixed random variable stream number to the random variables
+  * used by this model. Return the number of streams (possibly zero) that
+  * have been assigned. The Install() method should have previously been
+  * called by the user.
+  *
+  * \param c NetDeviceContainer of the set of net devices for which the 
+  *          CsmaNetDevice should be modified to use a fixed stream
+  * \param stream first stream index to use
+  * \return the number of stream indices assigned by this helper
+  */
+  int64_t AssignStreams (NetDeviceContainer c, int64_t stream);
+
 private:
   /*
    * \internal

src/csma/model/backoff.cc

@@ -19,6 +19,9 @@
  */
 
 #include "backoff.h"
+#include "ns3/log.h"
+
+NS_LOG_COMPONENT_DEFINE ("Backoff");
 
 namespace ns3 {
 
@@ -29,6 +32,7 @@ Backoff::Backoff ()
   m_maxSlots = 1000;
   m_ceiling = 10;
   m_maxRetries = 1000;
+  m_rng = CreateObject<UniformRandomVariable> ();
 
   ResetBackoffTime ();
 }
@@ -40,7 +44,7 @@ Backoff::Backoff(Time slotTime, uint32_t minSlots, uint32_t maxSlots, uint32_t c
   m_maxSlots = maxSlots;
   m_ceiling = ceiling;
   m_maxRetries = maxRetries;
-  m_rng = UniformVariable ();
+  m_rng = CreateObject<UniformRandomVariable> ();
 }
 
 Time
@@ -64,7 +68,7 @@ Backoff::GetBackoffTime (void)
       maxSlot = m_maxSlots;
     }
 
-  uint32_t backoffSlots = (uint32_t)m_rng.GetValue (minSlot, maxSlot);
+  uint32_t backoffSlots = (uint32_t)m_rng->GetValue (minSlot, maxSlot);
 
   Time backoff = Time (backoffSlots * m_slotTime);
   return backoff;
@@ -88,4 +92,12 @@ Backoff::IncrNumRetries (void)
   m_numBackoffRetries++;
 }
 
+int64_t
+Backoff::AssignStreams (int64_t stream)
+{
+  NS_LOG_FUNCTION (this << stream);
+  m_rng->SetStream (stream);
+  return 1;
+}
+
 } // namespace ns3

src/csma/model/backoff.h

@@ -24,7 +24,7 @@ Transmi */
 
 #include <stdint.h>
 #include "ns3/nstime.h"
-#include "ns3/random-variable.h"
+#include "ns3/random-variable-stream.h"
 
 namespace ns3 {
 
@@ -87,13 +87,23 @@ public:
    */
   void IncrNumRetries (void);
 
+ /**
+  * Assign a fixed random variable stream number to the random variables
+  * used by this model.  Return the number of streams (possibly zero) that
+  * have been assigned.
+  *
+  * \param stream first stream index to use
+  * \return the number of stream indices assigned by this model
+  */
+  int64_t AssignStreams (int64_t stream);
+
 private:
 
   /**
    * Number of times that the transmitter has tried to unsuccessfully transmit the current packet.
    */
   uint32_t m_numBackoffRetries;
-  UniformVariable m_rng;
+  Ptr<UniformRandomVariable> m_rng;
 };
 
 } // namespace ns3

src/csma/model/csma-net-device.cc

@@ -1014,4 +1014,10 @@ CsmaNetDevice::SupportsSendFrom () const
   return true;
 }
 
+int64_t
+CsmaNetDevice::AssignStreams (int64_t stream)
+{
+  return m_backoff.AssignStreams (stream);
+}
+
 } // namespace ns3

src/csma/model/csma-net-device.h

@@ -32,7 +32,6 @@
 #include "ns3/nstime.h"
 #include "ns3/data-rate.h"
 #include "ns3/ptr.h"
-#include "ns3/random-variable.h"
 #include "ns3/mac48-address.h"
 
 namespace ns3 {
@@ -322,6 +321,16 @@ public:
   virtual void SetPromiscReceiveCallback (PromiscReceiveCallback cb);
   virtual bool SupportsSendFrom (void) const;
 
+ /**
+  * Assign a fixed random variable stream number to the random variables
+  * used by this model.  Return the number of streams (possibly zero) that
+  * have been assigned.
+  *
+  * \param stream first stream index to use
+  * \return the number of stream indices assigned by this model
+  */
+  int64_t AssignStreams (int64_t stream);
+
 protected:
   /**
    * Perform any object release functionality required to break reference