gustavo's retcode patch for regression

.hgtags

@@ -27,3 +27,5 @@ f33cbf6b051c51d92db41b6fa825437958fbf801 ns-3.3-RC1
 a84f2ab246e691a88b527a84ce21896b95080070 ns-3.3-RC1
 654eed5f3ad03c04c2bcfb6852b5b4ae94260bc6 ns-3.3-RC2
 a66553c56a8f14644af6c229c83bb0a653cb3f32 ns-3.3-RC3
+dfd0bc16dc991313896f351530a3dc5a25f62e15 ns-3.3-RC4
+58ae52c5845ff03ba08dc921e13e6cf3604c810a ns-3.3-RC5

doc/tutorial/building-topologies.texi

@@ -105,6 +105,13 @@ familiar to you so far.
     LogComponentEnable("UdpEchoServerApplication", LOG_LEVEL_INFO);
 @end verbatim
 
+A fixed seed is provided to the random number generators so that they will
+generate repeatable results.
+
+@verbatim
+  RandomVariable::UseGlobalSeed (1, 1, 2, 3, 5, 8);
+@end verbatim
+
 Next, you will see some familiar code that will allow you to change the number
 of devices on the CSMA network via command line argument.  We did something
 similar when we allowed the number of packets sent to be changed in the section
@@ -657,6 +664,13 @@ the simulation.
     LogComponentEnable("UdpEchoServerApplication", LOG_LEVEL_INFO);
 @end verbatim
 
+A fixed seed is provided to the random number generators so that they will
+generate repeatable results.
+
+@verbatim
+  RandomVariable::UseGlobalSeed (1, 1, 2, 3, 5, 8);
+@end verbatim
+
 Next, you will see more familiar code that will allow you to change the number
 of devices on the CSMA and Wifi networks via command line argument.
 

doc/tutorial/conceptual-overview.texi

@@ -362,6 +362,21 @@ enable on each component.  These two lines of code enable debug logging at the
 INFO level for echo clients and servers.  This will result in the application
 printing out messages as packets are sent and received during the simulation.
 
+The next line of code is used to give a fixed seed to the random number 
+generators so that they will generate repeatable results.  In the example
+programs, it allows us to thouroughly document the output of the trace files
+in a consistent way.  Having a fixed seed also allows us to use the examples 
+in our regression testing framework.
+
+@verbatim
+  RandomVariable::UseGlobalSeed (1, 1, 2, 3, 5, 8);
+@end verbatim
+
+Random variables are very important in understanding how to get repeatable
+results, so you are encouraged to read the Doxygen and manual sections to
+understand what is going on there.  For us, the main concern is in making 
+random backoff algorithms consistent across runs.
+
 Now we will get directly to the business of creating a topology and running 
 a simulation.  We use the topology helper objects to make this job as
 easy as possible.

examples/first.cc

@@ -29,6 +29,8 @@ main (int argc, char *argv[])
   LogComponentEnable("UdpEchoClientApplication", LOG_LEVEL_INFO);
   LogComponentEnable("UdpEchoServerApplication", LOG_LEVEL_INFO);
 
+  RandomVariable::UseGlobalSeed (1, 1, 2, 3, 5, 8);
+
   NodeContainer nodes;
   nodes.Create (2);
 

examples/second.cc

@@ -39,6 +39,8 @@ main (int argc, char *argv[])
   LogComponentEnable("UdpEchoClientApplication", LOG_LEVEL_INFO);
   LogComponentEnable("UdpEchoServerApplication", LOG_LEVEL_INFO);
 
+  RandomVariable::UseGlobalSeed (1, 1, 2, 3, 5, 8);
+
   uint32_t nCsma = 3;
   CommandLine cmd;
   cmd.AddValue ("nCsma", "Number of \"extra\" CSMA nodes/devices", nCsma);

examples/third.cc

@@ -43,6 +43,8 @@ main (int argc, char *argv[])
   LogComponentEnable("UdpEchoClientApplication", LOG_LEVEL_INFO);
   LogComponentEnable("UdpEchoServerApplication", LOG_LEVEL_INFO);
 
+  RandomVariable::UseGlobalSeed (1, 1, 2, 3, 5, 8);
+
   uint32_t nCsma = 3;
   uint32_t nWifi = 3;
   CommandLine cmd;

src/applications/v4ping/v4ping.cc

@@ -108,6 +108,15 @@ V4Ping::Receive (Ptr<Socket> socket)
     }
 }
 
+void
+V4Ping::Write32 (uint8_t *buffer, uint32_t data)
+{
+  buffer[0] = (data >> 0) & 0xff;
+  buffer[1] = (data >> 8) & 0xff;
+  buffer[2] = (data >> 16) & 0xff;
+  buffer[3] = (data >> 24) & 0xff;
+}
+
 void 
 V4Ping::StartApplication (void)
 {
@@ -128,13 +137,28 @@ V4Ping::StartApplication (void)
   echo.SetSequenceNumber (m_seq);
   m_seq++;
   echo.SetIdentifier (0);
-  uint32_t data[4];
-  data[0] = GetNode ()->GetId ();
-  data[1] = GetApplicationId ();
+
+  //
+  // We must write quantities out in some form of network order.  Since there
+  // isn't an htonl to work with we just follow the convention in pcap traces
+  // (where any difference would show up anyway) and borrow that code.  Don't
+  // be too surprised when you see that this is a little endian convention.
+  //
+  uint8_t data[4 * sizeof(uint32_t)];
+  uint32_t tmp = GetNode ()->GetId ();
+  Write32 (&data[0 * sizeof(uint32_t)], tmp);
+
+  tmp = GetApplicationId ();
+  Write32 (&data[1 * sizeof(uint32_t)], tmp);
+
   int64_t now = Simulator::Now ().GetTimeStep ();
-  data[2] = now & 0xffffffff;
+  tmp = now & 0xffffffff;
+  Write32 (&data[2 * sizeof(uint32_t)], tmp);
+
   now >>= 32;
-  data[3] = now & 0xffffffff;
+  tmp = now & 0xffffffff;
+  Write32 (&data[3 * sizeof(uint32_t)], tmp);
+
   Ptr<Packet> dataPacket = Create<Packet> ((uint8_t *) &data, 16);
   echo.SetData (dataPacket);
   p->AddHeader (echo);

src/applications/v4ping/v4ping.h

@@ -18,6 +18,8 @@ public:
   virtual ~V4Ping ();
 
 private:
+  void Write32 (uint8_t *buffer, uint32_t data);
+
   // inherited from Application base class.
   virtual void StartApplication (void);
   virtual void StopApplication (void);

wscript

@@ -492,9 +492,11 @@ def shutdown():
         if not regression_traces:
             regression_traces = None
         try:
-            regression.run_regression(regression_traces)
+            retval = regression.run_regression(regression_traces)
         finally:
             os.chdir(_dir)
+        if retval:
+            sys.exit(retval)
 
     if Params.g_options.lcov_report:
         lcov_report()