#ifndef ns_myping_h
#define ns_mying_h

#include "agent.h"
#include "tclcl.h"
#include "packet.h"
#include "address.h"
#include "ip.h"

struct hdr_myping{
	char ret;
	double send_time;
};

class MyPingAgent : public Agent{
	public:
	   MyPingAgent();
	   int command(int argc, const char*const* argv);
	   void recv(Packet*, Handler*);
	protected:
	   int off_myping_;
	   int off_ip_;
};

#endif

#include "myping/myping.h"


static class MyPingHeaderClass : public PacketHeaderClass {
public:
   MyPingHeaderClass() : PacketHeaderClass("PacketHeader/MyPing",sizeof(hdr_myping)) {}

} class_mypinghdr;

static class MyPingClass : public TclClass{
public:
   MyPingClass() : TclClass("Agent/MyPing") {}
   TclObject* create(int, const char*const*) {
	return(new MyPingAgent());
} 

} class_myping;

MyPingAgent::MyPingAgent() : Agent(PT_MYPING)
{
  bind("packetSize_", &size_);
  bind("off_myping_", &off_myping_);
}

int MyPingAgent::command(int argc, const char*const* argv)
{
  if (argc == 2) {
    if (strcmp(argv[1], "send") == 0) {
      // Create a new packet
      Packet* pkt = allocpkt();
      // Access the Ping header for the new packet:
      hdr_myping* hdr = (hdr_myping*)pkt->access(off_myping_);
      //hdr_myping* hdr = hdr_myping::access(pkt);
      // Set the 'ret' field to 0, so the receiving node knows
      // that it has to generate an echo packet
      hdr->ret = 0;
      // Store the current time in the 'send_time' field
      hdr->send_time = Scheduler::instance().clock();
      // Send the packet
      send(pkt, 0);
      // return TCL_OK, so the calling function knows that the
      // command has been processed
      return (TCL_OK);
    }
  }
  // If the command hasn't been processed by PingAgent()::command,
  // call the command() function for the base class
  return (Agent::command(argc, argv));
}


void MyPingAgent::recv(Packet* pkt, Handler*)
{
  // Access the IP header for the received packet:
  off_ip_=hdr_ip::offset();
  hdr_ip* hdrip = (hdr_ip*)pkt->access(off_ip_);
  // Access the Ping header for the received packet:
  hdr_myping* hdr = (hdr_myping*)pkt->access(off_myping_);
  // Is the 'ret' field = 0 (i.e. the receiving node is being pinged)?
  if (hdr->ret == 0) {
    // Send an 'echo'. First save the old packet's send_time
    double stime = hdr->send_time;
    // Discard the packet
    Packet::free(pkt);
    // Create a new packet
    Packet* pktret = allocpkt();
    // Access the Ping header for the new packet:
    hdr_myping* hdrret = (hdr_myping*)pktret->access(off_myping_);
    // Set the 'ret' field to 1, so the receiver won't send another echo
    hdrret->ret = 1;
    // Set the send_time field to the correct value
    hdrret->send_time = stime;
    // Send the packet
    send(pktret, 0);
  } else {
    // A packet was received. Use tcl.eval to call the Tcl
    // interpreter with the ping results.
    // Note: In the Tcl code, a procedure 'Agent/Ping recv {from rtt}'
    // has to be defined which allows the user to react to the ping
    // result.
    char out[100];
    // Prepare the output to the Tcl interpreter. Calculate the round
    // trip time
    sprintf(out, "%s recv %d %3.1f", name(), 
            (hdrip->src_).addr_, 
	    (Scheduler::instance().clock()-hdr->send_time) * 1000);
    Tcl& tcl = Tcl::instance();
    tcl.eval(out);
    // Discard the packet
    Packet::free(pkt);
  }
}

#Create a simulator object
set ns [new Simulator]

#Open a trace file
set nf [open out.nam w]
$ns namtrace-all $nf

#Define a 'finish' procedure
proc finish {} {
        global ns nf
        $ns flush-trace
        close $nf
        exec nam out.nam &
        exit 0
}

#Create three nodes
set n0 [$ns node]
set n1 [$ns node]
set n2 [$ns node]

#Connect the nodes with two links
$ns duplex-link $n0 $n1 1Mb 10ms DropTail
$ns duplex-link $n1 $n2 1Mb 10ms DropTail

#Define a 'recv' function for the class 'Agent/MyPing'
Agent/MyPing instproc recv {from rtt} {
	$self instvar node_
	puts "node [$node_ id] received ping answer from \
              $from with round-trip-time $rtt ms."
}

#Create two ping agents and attach them to the nodes n0 and n2
set p0 [new Agent/MyPing]
$ns attach-agent $n0 $p0

set p1 [new Agent/MyPing]
$ns attach-agent $n2 $p1

#Connect the two agents
$ns connect $p0 $p1

#Schedule events
$ns at 0.2 "$p0 send"
$ns at 0.4 "$p1 send"
$ns at 0.6 "$p0 send"
$ns at 0.6 "$p1 send"
$ns at 1.0 "finish"

#Run the simulation
$ns run

ns-default.tcl:830:Agent/Ping set packetSize_ 64


ns-packet.tcl:155:      Ping    # Ping
ns-packet.tcl:267:#     { Ping off_ping_ }

ln: failed to create symbolic link `ns': File exists
ln: failed to create symbolic link `nam': File exists
Please compile your xgraph separately.
ln: failed to create symbolic link `sgb2ns': File exists
ln: failed to create symbolic link `sgb2hierns': File exists
ln: failed to create symbolic link `sgb2comns': File exists
ln: failed to create symbolic link `itm': File exists
ln: failed to create symbolic link `sgb2alt': File exists
ln: failed to create symbolic link `edriver': File exists

Ns-allinone package has been installed successfully.
Here are the installation places:
tcl8.4.18:	/home/partha/program/ns-allinone-2.34/{bin,include,lib}
tk8.4.18:		/home/partha/program/ns-allinone-2.34/{bin,include,lib}
otcl:		/home/partha/program/ns-allinone-2.34/otcl-1.13
tclcl:		/home/partha/program/ns-allinone-2.34/tclcl-1.19
ns:		/home/partha/program/ns-allinone-2.34/ns-2.34/ns
nam:	/home/partha/program/ns-allinone-2.34/nam-1.14/nam
gt-itm:   /home/partha/program/ns-allinone-2.34/itm, edriver, sgb2alt, sgb2ns, sgb2comns, sgb2hierns

----------------------------------------------------------------------------------

Please put /home/partha/program/ns-allinone-2.34/bin:/home/partha/program/ns-allinone-2.34/tcl8.4.18/unix:/home/partha/program/ns-allinone-2.34/tk8.4.18/unix
into your PATH environment; so that you'll be able to run itm/tclsh/wish/xgraph.

IMPORTANT NOTICES:

(1) You MUST put /home/partha/program/ns-allinone-2.34/otcl-1.13, /home/partha/program/ns-allinone-2.34/lib, 
    into your LD_LIBRARY_PATH environment variable.
    If it complains about X libraries, add path to your X libraries 
    into LD_LIBRARY_PATH.
    If you are using csh, you can set it like:
		setenv LD_LIBRARY_PATH <paths>
    If you are using sh, you can set it like:
		export LD_LIBRARY_PATH=<paths>

(2) You MUST put /home/partha/program/ns-allinone-2.34/tcl8.4.18/library into your TCL_LIBRARY environmental
    variable. Otherwise ns/nam will complain during startup.


After these steps, you can now run the ns validation suite with
cd ns-2.34; ./validate

For trouble shooting, please first read ns problems page 
http://www.isi.edu/nsnam/ns/ns-problems.html. Also search the ns mailing list archive
for related posts.

In file included from mac/mac-802_11Ext.cc:66:0:
mac/mac-802_11Ext.h: In member function ‘u_int32_t PHY_MIBExt::getHdrLen11()’:
mac/mac-802_11Ext.h:175:19: error: expected primary-expression before ‘struct’
mac/mac-802_11Ext.h:175:41: error: ‘dh_body’ was not declared in this scope
mac/mac-802_11Ext.h:175:51: error: ‘offsetof’ was not declared in this scope
mac/mac-802_11Ext.h:177:3: warning: control reaches end of non-void function [-Wreturn-type]
make: *** [mac/mac-802_11Ext.o] Error 1