main.cpp

 /*main.cpp
  *
  *The starting point of the network simulator
  *-Include all network header files
  *-initilize the network
  *-initialize the traffic manager and set it to run
  *
  *
  */
 #include <sys/time.h>

 #include <string>
 #include <cstdlib>
 #include <iostream>
 #include <fstream>

 #include <sstream>
 #include "booksim.hpp"
 #include "routefunc.hpp"
 #include "traffic.hpp"
 #include "booksim_config.hpp"
 #include "trafficmanager.hpp"
 #include "random_utils.hpp"
 #include "network.hpp"
 #include "injection.hpp"
 #include "power_module.hpp"

 ///////////////////////////////////////////////////////////////////////////////
 //Global declarations
 //////////////////////

  /* the current traffic manager instance */
 TrafficManager * trafficManager = NULL;

 int GetSimTime() {
   return trafficManager->getTime();
 }

 class Stats; //数据实体
 Stats * GetStats(const std::string & name) {
   Stats* test =  trafficManager->getStats(name);
   if(test == ){
     cout<<"warning statistics "<<name<<" not found"<<endl;
   }
   return test;
 }

 /* printing activity factor*/
 bool gPrintActivity;

 int gK;//radix, the number of routers per dimension
 int gN;//dimension, such as 1D, 2D
 int gC;//concentration, the number of nodes sharing a single router

 int gNodes;

 //generate nocviewer trace
 bool gTrace;

 ostream * gWatchOut;

 bool Simulate( BookSimConfig const & config )
 {
   vector<Network *> net;

   int subnets = config.GetInt("subnets");
   /*To include a new network, must register the network here
    *add an else if statement with the name of the network
    */
   //resize改变当前使用数据的大小,如果它比当前使用的大,填充默认值
   net.resize(subnets);
   for (int i = ; i < subnets; ++i) {
       /*ostringstream
       *通常用于执行C风格的串流的输出操作，
       *格式化字符串，避免申请大量的缓冲区，替代sprintf
       *该类能够根据内容自动分配内存,对内存的管理也是相当的到位
       *取得ostringstream里的内容可以通过str()和str(string&)成员函数
       */
     ostringstream name;
     name << "network_" << i;
     net[i] = Network::New( config, name.str() );
   }

   /*tcc and characterize are legacy
    *not sure how to use them
    */
   //assert如果它的条件返回错误，则终止程序执行
   assert(trafficManager == NULL);
   trafficManager = TrafficManager::New( config, net ) ;

   /*Start the simulation run
    */

   double total_time; /* Amount of time we've run */
   struct timeval start_time, end_time; /* Time before/after user code */
   total_time = 0.0;
   //获得当前精确时间
   gettimeofday(&start_time, NULL);

   bool result = trafficManager->Run() ;

   gettimeofday(&end_time, NULL);
   total_time = ((double)(end_time.tv_sec) + (double)(end_time.tv_usec)/1000000.0)
             - ((double)(start_time.tv_sec) + (double)(start_time.tv_usec)/1000000.0);

   cout<<"Total run time "<<total_time<<endl;

   for (int i=; i<subnets; ++i) {

     ///Power analysis
     if(config.GetInt("sim_power") > ){
       Power_Module pnet(net[i], config);
       pnet.run();
     }

     delete net[i];
   }

   delete trafficManager;
   trafficManager = NULL;

   return result;
 }

 int main( int argc, char **argv )
 {

   BookSimConfig config;

   if ( !ParseArgs( &config, argc, argv ) ) {
     cerr << "Usage: " << argv[] << " configfile... [param=value...]" << endl;
     return ;
  } 

   /*initialize routing, traffic, injection functions
    */
   InitializeRoutingMap( config );

   gPrintActivity = (config.GetInt("print_activity") > );
   gTrace = (config.GetInt("viewer_trace") > );

   string watch_out_file = config.GetStr( "watch_out" );
   if(watch_out_file == "") {
     gWatchOut = NULL;
   } else if(watch_out_file == "-") {
     gWatchOut = &cout;
   } else {
     gWatchOut = new ofstream(watch_out_file.c_str());
   }

   /*configure and run the simulator
    */
   bool result = Simulate( config );
   return result ? - : ;
 }