rfpipe/downstreamqueue.cc

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/*
 * Copyright (c) 2013 - Adjacent Link LLC, Bridgewater, New Jersey
 * Copyright (c) 2010 - DRS CenGen, LLC, Columbia, Maryland
 * All rights reserved.
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#include "downstreamqueue.h"

namespace 
{
  const std::uint16_t QUEUE_SIZE_DEFAULT{0xFF};
}

EMANE::Models::RFPipe::DownstreamQueue::DownstreamQueue():
  maxQueueSize_{QUEUE_SIZE_DEFAULT},
  numDiscards_{},
  pNumHighWaterMark_{}
{}


EMANE::Models::RFPipe::DownstreamQueue::~DownstreamQueue() 
{}


void EMANE::Models::RFPipe::DownstreamQueue::registerStatistics(StatisticRegistrar & statisticRegistrar)
{ 
  pNumHighWaterMark_ =
     statisticRegistrar.registerNumeric<std::uint32_t>("numHighWaterMark",
                                                       StatisticProperties::CLEARABLE);
}



size_t 
EMANE::Models::RFPipe::DownstreamQueue::getNumDiscards(bool bClear) 
{ 
   size_t result{numDiscards_};

   if(bClear)
     {
       numDiscards_ = 0;
     }

   return result;
}


size_t 
EMANE::Models::RFPipe::DownstreamQueue::getCurrentDepth()
{ 
   return queue_.size();
}


size_t 
EMANE::Models::RFPipe::DownstreamQueue::getMaxCapacity()
{ 
   return maxQueueSize_;
}


std::pair<EMANE::Models::RFPipe::DownstreamQueueEntry,bool>
EMANE::Models::RFPipe::DownstreamQueue::dequeue()
{ 
  if(queue_.empty())
     {
       return {{},false};
     }

  DownstreamQueueEntry entry{queue_.front()};
  
  queue_.pop();
  
  return {entry,true};
}


std::vector<EMANE::Models::RFPipe::DownstreamQueueEntry>
EMANE::Models::RFPipe::DownstreamQueue::enqueue(DownstreamQueueEntry &entry) 
{ 
   std::vector<DownstreamQueueEntry> result;

   // check for queue overflow
   while(queue_.size() >= maxQueueSize_) 
     {
       ++numDiscards_;

       result.push_back(std::move(queue_.front()));

       queue_.pop();
     }

   queue_.push(std::move(entry));

   if(queue_.size() > pNumHighWaterMark_->get()) 
     {
       *pNumHighWaterMark_ = queue_.size();
     }

   return result;
}



const EMANE::Models::RFPipe::DownstreamQueueEntry & 
EMANE::Models::RFPipe::DownstreamQueue::peek()
{ 
   return queue_.front();
}