From 418a3fae425b5024a146ce7883efde885e172567 Mon Sep 17 00:00:00 2001
From: Craig Dowell <craigdo@ee.washington.edu>
Date: Thu, 8 May 2008 11:16:12 -0700
Subject: [PATCH] bug 170

---
 src/helper/internet-stack-helper.cc | 18 ++++++++++++++++++
 src/helper/internet-stack-helper.h  |  8 ++++++++
 2 files changed, 26 insertions(+)

diff --git a/src/helper/internet-stack-helper.cc b/src/helper/internet-stack-helper.cc
index 8285f29d8..8b6661bfb 100644
--- a/src/helper/internet-stack-helper.cc
+++ b/src/helper/internet-stack-helper.cc
@@ -25,12 +25,28 @@
 #include "ns3/internet-stack.h"
 #include "ns3/packet-socket-factory.h"
 #include "ns3/config.h"
+#include "ns3/simulator.h"
 
 namespace ns3 {
 
 std::vector<InternetStackHelper::Trace> InternetStackHelper::m_traces;
 std::string InternetStackHelper::m_pcapBaseFilename;
 
+void
+InternetStackHelper::Cleanup (void)
+{
+  uint32_t illegal = std::numeric_limits<uint32_t>::max();
+
+  for (std::vector<Trace>::iterator i = m_traces.begin ();
+       i != m_traces.end (); i++)
+  {
+    i->nodeId = illegal;
+    i->interfaceId = illegal;
+    i->writer = 0;
+  }
+  m_traces.clear ();
+}
+
 void 
 InternetStackHelper::Install (NodeContainer c)
 {
@@ -52,6 +68,8 @@ InternetStackHelper::Install (NodeContainer c)
 void
 InternetStackHelper::EnablePcapAll (std::string filename)
 {
+  Simulator::ScheduleDestroy (&InternetStackHelper::Cleanup);
+
   InternetStackHelper::m_pcapBaseFilename = filename;
   Config::Connect ("/NodeList/*/$ns3::Ipv4L3Protocol/Tx",
                               MakeCallback (&InternetStackHelper::LogTxIp));
diff --git a/src/helper/internet-stack-helper.h b/src/helper/internet-stack-helper.h
index 9241ee3a0..74f1054e0 100644
--- a/src/helper/internet-stack-helper.h
+++ b/src/helper/internet-stack-helper.h
@@ -49,10 +49,18 @@ public:
    *
    * Enable pcap output on each protocol instance which is of the
    * ns3::Ipv4L3Protocol type.  Both Tx and Rx events will be logged.
+   *
+   * \warning If you perform multiple simulations in a single script,
+   * each iteration of the simulation will result in the trace files
+   * being overwritten.  We don't attempt to anticipate what a user
+   * might actually want to do, so we leave it up to them.  If you want
+   * to save any particular data, do so manually at inter-simulation 
+   * time.
    */
   static void EnablePcapAll (std::string filename);
 
 private:
+  static void Cleanup (void);
   static void LogRxIp (std::string context, Ptr<const Packet> packet, uint32_t deviceId);
   static void LogTxIp (std::string context, Ptr<const Packet> packet, uint32_t deviceId);
   static Ptr<PcapWriter> GetStream (uint32_t nodeId, uint32_t interfaceId);