SendBuffer.c

/************************************************************************************
* Copyright (C) 2023                                                               *
* TETCOS, Bangalore. India                                                         *
*                                                                                  *
* Tetcos owns the intellectual property rights in the Product and its content.     *
* The copying, redistribution, reselling or publication of any or all of the       *
* Product or its content without express prior written consent of Tetcos is        *
* prohibited. Ownership and / or any other right relating to the software and all *
* intellectual property rights therein shall remain at all times with Tetcos.      *
*                                                                                  *
* Author:    Shashi Kant Suman                                                       *
*                                                                                  *
* ---------------------------------------------------------------------------------*/
#include "main.h"
#include "List.h"
#include "DSR.h"
/**
This function adds the packet to send buffer.
*/
bool fn_NetSim_DSR_AddToSendBuffer(DSR_SEND_BUFFER** sendBuffer,NetSim_PACKET* packet,double dTime)
{
    NETSIM_IPAddress dest = packet->pstruNetworkData->szDestIP;
    DSR_SEND_BUFFER* temp = *sendBuffer;
    bool flag=true;
    while(temp)
    {
        if(!IP_COMPARE(dest,temp->target))
        {
            flag = false;
            break;
        }
        temp = LIST_NEXT(temp);
    }
    if(!temp)
        temp = (DSR_SEND_BUFFER*)SENDBUFFER_ALLOC();
    if(!temp->packet)
    {
        temp->dTime = dTime;
        temp->packet = packet;
        temp->target = dest;
    }
    else
    {
        NetSim_PACKET* temp_packet=temp->packet;
        while(temp_packet->pstruNextPacket)
            temp_packet = temp_packet->pstruNextPacket;
        temp_packet->pstruNextPacket = packet;
    }
    if(flag)
        LIST_ADD_LAST((void**)sendBuffer,temp);
    return flag;
}
/**
This function Empties the send buffer.
*/
void fn_NetSim_DSR_EmptySendBuffer(NETSIM_IPAddress targetAddress,NETSIM_ID nDeviceId)
{
    DSR_SEND_BUFFER* sendBuffer=DSR_DEV_VAR(nDeviceId)->pstruSendBuffer;
    while(sendBuffer)
    {
        if(!IP_COMPARE(sendBuffer->target,targetAddress))
        {
            while(sendBuffer->packet)
            {
                NetSim_PACKET* temp = sendBuffer->packet;
                sendBuffer->packet = temp->pstruNextPacket;
                temp->pstruNextPacket = NULL;
                fn_NetSim_Packet_FreePacket(temp);
                //Update the metrics
                DSR_DEV_VAR(nDeviceId)->dsrMetrics.packetDropped++;
            }
            IP_FREE(sendBuffer->target);
            LIST_FREE(&DSR_DEV_VAR(nDeviceId)->pstruSendBuffer,sendBuffer);
            break;
        }
        sendBuffer = LIST_NEXT(sendBuffer);
    }
}
/**
This function checks if the route cache has the route to the target and transmits the packet 
if it has.
*/
void fn_NetSim_DSR_CheckSendBuffer(NETSIM_ID nDeviceId,double dTime)
{
    DSR_SEND_BUFFER* sendBuffer=DSR_DEV_VAR(nDeviceId)->pstruSendBuffer;
    DSR_ROUTE_CACHE* routeCache=DSR_DEV_VAR(nDeviceId)->pstruRouteCache;
    while(sendBuffer)
    {
        int ntxflag=0;
        NETSIM_IPAddress target = sendBuffer->target;
        while(routeCache)
        {
            unsigned int nLoop;
            for(nLoop=0;nLoop<routeCache->nLength;nLoop++)
            {
                if(!IP_COMPARE(target,routeCache->address[nLoop]))
                {
                    //Route found
                    DSR_TRANSMIT_SEND_BUFFER(sendBuffer,
                        nDeviceId,dTime);
                    ntxflag=1;
                    break;
                }
            }
            routeCache = LIST_NEXT(routeCache);
        }
        if(ntxflag)
        {
            DSR_SEND_BUFFER* temp = sendBuffer;
            sendBuffer=LIST_NEXT(sendBuffer);
            DSR_EMPTY_SEND_BUFFER(temp->target,nDeviceId);
            continue;
        }
        sendBuffer = LIST_NEXT(sendBuffer);
    }
}
/**
This function transmits the packets from sent buffer
*/
int fn_NetSim_DSR_TransmitPacketFromSendBuffer(DSR_SEND_BUFFER* sendBuffer,
    NETSIM_ID nDeviceId,
    double dTime)
{
    NetSim_EVENTDETAILS eventDetails;
    memset(&eventDetails,0,sizeof*(&eventDetails));
    while(sendBuffer->packet)
    {
        NetSim_PACKET* packet = sendBuffer->packet;
        sendBuffer->packet = packet->pstruNextPacket;
        packet->pstruNextPacket = NULL;
        eventDetails.dEventTime = dTime;
        eventDetails.dPacketSize = fnGetPacketSize(packet);
        if(packet->pstruAppData)
        {
            eventDetails.nApplicationId = packet->pstruAppData->nApplicationId;
            eventDetails.nSegmentId = packet->pstruAppData->nSegmentId;
        }
        else
        {
            eventDetails.nApplicationId = 0;
            eventDetails.nSegmentId = 0;
        }
        eventDetails.nDeviceId = nDeviceId;
        eventDetails.nDeviceType = NETWORK->ppstruDeviceList[nDeviceId-1]->nDeviceType;
        eventDetails.nEventType = NETWORK_OUT_EVENT;
        eventDetails.nInterfaceId = 1;
        eventDetails.nPacketId = packet->nPacketId;
        eventDetails.nProtocolId = fn_NetSim_Stack_GetNWProtocol(nDeviceId);
        eventDetails.nSubEventType = 0;
        eventDetails.pPacket = packet;
        fnpAddEvent(&eventDetails);
    }
    return 0;
}