/* File: server.c */

/*
 *********************************************************************
   ALTERNATING BIT AND GO-BACK-N NETWORK EMULATOR

   Revised version of code by J.F. Kurose

   From the companion website for 
   _Computer Networking: A Top-Down Approach Featuring the Internet_
   by J.F. Kurose and K. W. Ross
   (c) 2001 by Addison Wesley Longman

   Based on document at <URL:http://occawlonline.pearsoned.com/
   bookbind/pubbooks/kurose-ross1/chapter4/custom12/deluxe-content.html>
   (as of 02 July 2002)
 *********************************************************************
*/

#include <stdio.h>
#include "message.h"
#include "payload.h"
#include "packet.h"
#include "server.h"
#include "KRnet.h"

/* prototypes for private functions */
static void startTimer(float howlong);
static void cancelTimer(void);
static void sendToNWSlayer(packet_t packet);
static void deliverToAppLayer(char datasent[]);


/* ****************** */
/*  Server functions  */
/* ****************** */

void sendToNWSlayer(packet_t packet) {
  toNWSlayer(Server, packet);
} /* sendToNWSlayer() */

void deliverToAppLayer(char datasent[]) {
  toAppLayer(Server, datasent);
} /* deliverToAppLayer() */

void
startTimer(float howlong) {
  startServerTimer(howlong);
} /* startTimer() */

void
cancelTimer(void) {
  stopServerTimer();
} /* cancelTimer() */


/******** STUDENTS WRITE THESE NEXT THREE (OR FOUR) ROUTINES ********/

/*-------------*/
/* serverInit  */
/*             *---------------------------------------------------*/
/* Called only once, before any other Server (entity B) routines   */
/* are called.  You can use it to do any initialization.           */
/*-----------------------------------------------------------------*/
void
serverInit(void) {

} /* serverInit() */


/*------------*/
/* serverEnd  */
/*            *----------------------------------------------------*/
/* Called only once, after all other Server (entity B) routines    */
/* are called.  You can use it to print any final output.          */
/*-----------------------------------------------------------------*/
void
serverEnd(void) {
	
}/* serverEnd() */


/*--------------*/
/* serverInput  */
/*              *--------------------------------------------------*/
/*                                                                 */
/* called from layer 3 (Network Services), when a packet arrives   */
/* for layer 4 (Transport) at Server (entity B)                    */ 
/*                                                                 */
/* Note that with simplex transfer from Client (entity A) to       */
/* Server (entity B), there is no Server_output()                  */ 
/*-----------------------------------------------------------------*/
void
serverInput(packet_t packet) {

}/* serverInput() */


/*-----------------------*/
/* serverTimerinterrupt  */
/*                       *-----------------------------------------*/
/*                                                                 */
/* Called when the server's timer goes off                         */
/*-----------------------------------------------------------------*/
void
serverTimerInterrupt(void) {

} /* serverTimerInterrupt() */


/*---------------*/
/* serverOutput  */
/*               *-------------------------------------------------*/
/*                                                                 */
/* OPTIONAL: used only for bidirectional (duplex) transfer.        */
/*-----------------------------------------------------------------*/
void
serverOutput(message_t message) {

	return;
} /* serverOutput()*/


/*--------------------------*/
/* serverCanSendMorePackets */
/*                          *--------------------------------------*/
/*                                                                 */
/* called from the application layer (layer 5) , before passing    */
/* data to GBN layer, return true(nonzero) if sliding window is    */
/* not full, else return false (zero)                              */
/*                                                                 */
/* OPTIONAL: used only for bidirectional (duplex) transfer.        */
/*-----------------------------------------------------------------*/
int  serverCanSendMorePkt(void) {

/*
 	if (nextseqnum < base + N )
 		return true;
 	else
 		return false;
*/
	
	return 0;
}

/* EOF (server.c) */