MobileNode.cc

// Copyright 2008 Michael Marsh, University of Maryland.
//
// This file is part of pydtn.
//
// pydtn is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// pydtn is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with pydtn.  If not, see <http://www.gnu.org/licenses/>.
//
// The views and conclusions contained in the software and documentation
// are those of the authors and should not be interpreted as representing
// official policies, either expressed or implied, of the University
// of Maryland.
//
// pydtn extends and embeds the Python interpreter, which is
// Copyright 2001-2006 Python Software Foundation, All Rights Reserved,
// and is released under the PSF License Agreement.
//
// RANLUX random number generation uses the Boost library,
// Copyright 1994-2006 by various authors (details in individual files),
// which is released under the Boost Software License, Version 1.0.

#include "simlpy/interpreter_defs.h"
#include "simlpy/interpreter_hooks.h"

#include "MobileNode.h"
#include "BeaconConsumer.h"
#include "MobileApp.h"
#include "pydtn/BundleEvent.h"
#include "simlpy/Clock.h"
#include "simlpy/SimulationException.h"

#include <iostream>
#include <stdlib.h>

using namespace Mobility;

const std::string MobileNode::kIdentifier( "node:mobile" );

MobileNode::MobileNode() :
   m_beaconTime( 0 )
{
   m_beaconC = new BeaconConsumer( this );
   addConsumer( m_beaconC );
}

MobileNode::~MobileNode()
{
   // We don't hold the memory to the BeaconConsumer here.
}

Entity*
MobileNode::create() const
{
   MobileNode* n = new MobileNode;
   n->trigger();
   return n;
}

void
MobileNode::configure( const ArgList& args )
{
   unsigned int nargs = args.size();
   if ( nargs < 2 )
   {
      std::cerr << "config() takes at least 2 arguments ("
                << nargs << " given)"
                << std::endl;
      throw SimulationException( __FILE__ , __LINE__ );
   }
   std::string command = parse_string(args[0]);
   if ( "position" == command )
   {
      if ( nargs < 2 )
      {
         std::cerr << "config('position') requires at least two coordinates"
                   << std::endl;
         throw SimulationException( __FILE__ , __LINE__ );
      }
      Position pos = parse_position( args[1] );
      setWaypoint( Presence( Clock::time(), pos, Time() ) );
      return;
   }
   if ( "beacon" == command )
   {
      if ( nargs < 2 )
      {
         std::cerr << "config('beacon') requires at least two coordinates"
                   << std::endl;
         throw SimulationException( __FILE__ , __LINE__ );
      }
      if ( 0 == m_beaconC )
      {
         std::cerr << "No beacon manager was found at this node." << std::endl;
         throw SimulationException( __FILE__ , __LINE__ );
      }
      m_beaconTime = parse_double( args[1] );
      double t = 3 * m_beaconTime;
      long int ts = (long int) ::floor( t );
      long int tus = (long int) ( Time::MILLION * ( t - ::floor(t) ) );
      m_beaconC->setTimeout( Time(ts,tus) );
      return;
   }
   WrapNode::configure(args);
}

void
MobileNode::emit( const ArgList& args )
{
   unsigned int nargs = args.size();
   if ( nargs < 3 )
   {
      std::cerr << "emit() takes at least 3 arguments ("
                << nargs << " given)"
                << std::endl;
      throw SimulationException( __FILE__ , __LINE__ );
   }

   Time t = parse_time(args[0]);

   std::string command = parse_string(args[1]);

   if ( "waypoint" == command )
   {
      if ( nargs < 6 )
      {
         std::cerr << "emit(t,'waypoint') takes at least 6 arguments ("
                   << nargs << " given)"
                   << std::endl;
         throw SimulationException( __FILE__ , __LINE__ );
      }
      Time wpt = parse_time(args[2]);
      Time wpd = parse_time(args[3]);
      Position pos = parse_position( args[4] );
      Clock::schedule( new WaypointEvent(this,this,t,Presence(wpt,pos,wpd)) );
      return;
   }

   WrapNode::emit(args);
}

InterpreterItem
MobileNode::get( const ArgList& args )
{
   unsigned int nargs = args.size();
   if ( 0 == nargs )
   {
      std::cerr << "No attribute specified" << std::endl;
      throw SimulationException( __FILE__ , __LINE__ );
   }

   std::string attr = parse_string(args[0]);

   if ( "position" == attr )
   {
      Position p = position();
      ArgList alist;
      alist.push_back( construct_double( p.x() ) );
      alist.push_back( construct_double( p.y() ) );
      alist.push_back( construct_double( p.z() ) );
      return construct_list( alist );
   }
   if ( "beacon_interval" == attr )
   {
      return construct_double( m_beaconTime );
   }
   if ( "last_beacon" == attr )
   {
      ArgList alist;
      alist.push_back( construct_long( m_lastBeacon.tv.tv_sec ) );
      alist.push_back( construct_long( m_lastBeacon.tv.tv_usec ) );
      return construct_list( alist );
   }
   if ( "visible" == attr )
   {
      if ( 0 == m_beaconC )
      {
         std::cerr << "mobile node has no beacon consumer attached"
                   << std::endl;
         throw SimulationException( __FILE__ , __LINE__ );
      }
      return m_beaconC->visible_list();
   }

   return WrapNode::get(args);
}

void
MobileNode::addMobileApp( MobileApp* app )
{
   if ( 0 == app ) return;
   addApplication(app);
   m_mobileApps.push_back(app);
}

bool
MobileNode::handler( WaypointEvent& event )
{
   setWaypoint( event.waypoint() );
   return true;
}

bool
MobileNode::handler( HelloTrigger& event )
{
   if ( 0 == m_beaconC ) return false;
   Time t = Clock::time();

   // Do we need to send a HELLO message?
   bool needBeacon = m_beaconC->lastSend() <= m_lastBeacon;
   m_lastBeacon = m_beaconC->lastSend();
   if ( needBeacon )
   {
      DTN::Bundle::BundleType type =
         DTN::Bundle::kBcast | DTN::Bundle::kNoACK;
      Time e = t + bundleLifetime();
      DTN::Bundle* b =
         new DTN::Bundle( node().nextSeq(),
                          addr(),
                          addr(),
                          DTN::ByteString(),
                          t.tv,
                          e.tv,
                          type );
      if ( 0 != b )
      {
         // We don't add this bundle to the stable store, hence the "false".
         Clock::tentative( new BundleEvent(this,this,t,t,b,false) );
         m_lastBeacon = t;
      }
   }

   // Schedule the next trigger event.
   double d = m_beaconTime/2 + m_beaconTime*prng();
   long int ds = (long int) ::floor(d);
   long int dus = (long int) ( Time::MILLION * ( d - ::floor(d) ) );
   Time tTrig = t + Time(ds,dus);
   Clock::tentative( new HelloTrigger(this,this,tTrig) );

   m_beaconC->clean();
   return true;
}

Position
MobileNode::position() const
{
   return position( Clock::time() );
}

Position
MobileNode::position( const Time& t ) const
{
   // We need at least one actual point for this to be meaningful.
   if ( 0 == m_waypoints.size() ) return Position();

   Presence key( t, Position(), Time() );
   PresenceSet::const_iterator after = m_waypoints.lower_bound(key);
   PresenceSet::const_iterator before = after;
   --before;

   // The specified time is after the last movement completed.
   if ( m_waypoints.end() == after )
   {
      return before->position();
   }

   // We're exactly at a waypoint.
   if ( *after == t )
   {
      return after->position();
   }
   // Or we're paused at a waypoint.
   if ( ( t - before->time() ) < before->duration() )
   {
      return before->position();
   }

   // We're before the first waypoint (which shouldn't generally happen).
   if ( m_waypoints.begin() == after )
   {
      return Position();
   }

   // The normal case.  We need to interpolate the position.
   Presence current = before->towards( *after, t );

   return current.position();
}

bool
MobileNode::visible( const DTN::ByteString& addr )
{
   if ( 0 == m_beaconC ) return false;
   return m_beaconC->visible(addr);
}

void
MobileNode::trigger()
{
   Clock::tentative( new HelloTrigger(this,this,Clock::time()) );
}

void
MobileNode::notifyApps( const DTN::ByteString& addr )
{
   MobileAppList::iterator itr = m_mobileApps.begin();
   MobileAppList::iterator end = m_mobileApps.end();
   for ( ; itr != end ; ++itr )
   {
      (*itr)->newNeighbor(addr);
   }
}

void
MobileNode::setWaypoint( const Presence& wp )
{
   if ( wp.time() < Clock::time() )
   {
      std::cerr << "Cannot schedule a waypoint in the past"
                << std::endl;
      throw SimulationException( __FILE__ , __LINE__ );
   }
   m_waypoints.insert( wp );
}

Position
MobileNode::parse_position( const InterpreterItem p )
{
   double x = 0;
   double y = 0;
   double z = 0;
   if ( ! PyList_Check( p ) )
   {
      throw SimulationException( __FILE__ , __LINE__ );
   }
   int n = PyList_Size( p );

   if ( n < 2 )
   {
      throw SimulationException( __FILE__ , __LINE__ );
   }
   x = parse_double( PyList_GetItem(p,0) );
   y = parse_double( PyList_GetItem(p,1) );
   if ( n > 2 )
   {
      z = parse_double( PyList_GetItem(p,2) );
   }
   return Position( x, y, z );
}

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