25#include "ns3/packet.h"
28#include "ns3/tcp-option-ts.h"
43 .SetGroupName (
"Internet")
45 .AddTraceSource (
"UnackSequence",
46 "First unacknowledged sequence number (SND.UNA)",
48 "ns3::SequenceNumber32TracedValueCallback")
61 : m_maxBuffer (32768), m_size (0), m_sentSize (0), m_firstByteSeq (n)
68 PacketList::iterator it;
199 NS_LOG_LOGIC (
"Rejected. Not enough room to buffer packet.");
212 return static_cast<uint32_t> (lastSeq - seq);
215 NS_LOG_ERROR (
"Requested a sequence beyond our space (" << seq <<
" > " << lastSeq <<
216 "). Returning 0 for convenience.");
226 "Requested a sequence number which is not in the buffer anymore");
246 NS_LOG_DEBUG (
"Returning already sent item " << *outItem <<
" from " << *
this);
251 "Requesting a piece of new data with an hole");
258 NS_LOG_DEBUG (
"Returning new item " << *outItem <<
" from " << *
this);
274 "Returning an item " << *outItem <<
" with SND.UNA as " <<
287 NS_LOG_INFO (
"AppList start at " << startOfAppList <<
", sentSize = " <<
291 numBytes, startOfAppList);
314 bool listEdited =
false;
321 if ((*it)->m_startSeq == seq)
328 if ((! (*next)->m_sacked) && ((*it)->m_lost == (*next)->m_lost))
330 s =
std::min(s, (*it)->m_packet->GetSize () + (*next)->m_packet->GetSize ());
335 s =
std::min(s, (*it)->m_packet->GetSize ());
340 s =
std::min(s, (*it)->m_packet->GetSize ());
357std::pair <TcpTxBuffer::PacketList::const_iterator, SequenceNumber32>
371 ret = std::make_pair (it, beginOfCurrentPacket);
383 NS_ASSERT (t1 !=
nullptr && t2 !=
nullptr);
397 NS_LOG_INFO (
"Split of size " << size <<
" result: t1 " << *t1 <<
" t2 " << *t2);
403 bool *listEdited)
const
437 PacketList::iterator it =
list.begin ();
440 while (it !=
list.end ())
443 currentPacket = currentItem->
m_packet;
451 if (seq < beginOfCurrentPacket + currentPacket->
GetSize ())
454 if (seq == beginOfCurrentPacket)
457 outItem = currentItem;
458 NS_LOG_INFO (
"Current packet starts at seq " << seq <<
459 " ends at " << seq + currentPacket->
GetSize ());
461 else if (seq > beginOfCurrentPacket)
466 NS_LOG_INFO (
"we are at " << beginOfCurrentPacket <<
467 " searching for " << seq <<
468 " and now we recurse because packet ends at "
469 << beginOfCurrentPacket + currentPacket->
GetSize ());
471 SplitItems (firstPart, currentItem, seq - beginOfCurrentPacket);
474 list.insert (it, firstPart);
484 NS_FATAL_ERROR (
"seq < beginOfCurrentPacket: our data is before");
490 beginOfCurrentPacket += currentPacket->
GetSize ();
501 if (seq + numBytes <= beginOfCurrentPacket + currentPacket->
GetSize ())
504 if (numBytes == currentPacket->
GetSize ())
532 else if (numBytes < currentPacket->
GetSize ())
537 SplitItems (firstPart, currentItem, numBytes);
540 list.insert (it, firstPart);
553 if (++it ==
list.end ())
557 NS_LOG_WARN (
"Cannot reach the end, but this case is covered "
558 "with conditional statements inside CopyFromSequence."
559 "Something has gone wrong, report a bug");
588 NS_ASSERT (t1 !=
nullptr && t2 !=
nullptr);
590 NS_LOG_INFO (
"Merging " << *t2 <<
" into " << *t1);
593 "Merging one sacked and another not sacked. Impossible");
595 "Merging one lost and another not lost. Impossible");
624 NS_LOG_INFO (
"Situation after the merge: " << *t1);
684 while (
m_size > 0 && offset > 0)
713 ". Remaining data " <<
m_size);
715 if (!beforeDelCb.
IsNull ())
736 NS_LOG_INFO (
"Fragmented one packet by size " << offset <<
737 ", new size=" <<
pktSize <<
" resulting item is " <<
738 *item <<
" status: " << *
this);
759 NS_LOG_INFO (
"Moving the SACK flag from the HEAD to another segment");
765 "While removing up to " << seq <<
" we get SND.UNA to " <<
776 NS_LOG_LOGIC (
"Buffer status after discarding data " << *
this);
787 NS_LOG_INFO (
"Updating scoreboard, got " <<
list.size () <<
" blocks to analyze");
791 for (
auto option_it =
list.begin (); option_it !=
list.end (); ++option_it)
793 PacketList::iterator item_it =
m_sentList.begin ();
798 NS_LOG_INFO (
"Not updating scoreboard, the option block is outside the sent list");
811 if (beginOfCurrentPacket >= (*option_it).first
812 && beginOfCurrentPacket +
pktSize <= (*option_it).second)
814 if ((*item_it)->m_sacked)
818 ", checking sentList for block " << *(*item_it) <<
819 ", found in the sackboard already sacked");
823 if ((*item_it)->m_lost)
825 (*item_it)->m_lost =
false;
826 m_lostOut -= (*item_it)->m_packet->GetSize ();
829 (*item_it)->m_sacked =
true;
831 bytesSacked += (*item_it)->m_packet->GetSize ();
836 m_highestSack = std::make_pair (item_it, beginOfCurrentPacket);
840 ", checking sentList for block " << *(*item_it) <<
841 ", found in the sackboard, sacking, current highSack: " <<
850 else if (beginOfCurrentPacket +
pktSize > (*option_it).second)
854 ", checking sentList for block " << *(*item_it) <<
855 "], not found, breaking loop");
859 beginOfCurrentPacket +=
pktSize;
886 NS_LOG_INFO (
"Status before the update: " << *
this <<
887 ", will start from the latest sent item");
891 NS_LOG_INFO (
"Status before the update: " << *
this <<
923 NS_LOG_INFO (
"Status after the update: " << *
this);
933 PacketList::const_iterator it;
945 if (beginOfCurrentPacket >= seq)
947 if ((*it)->m_lost ==
true)
949 NS_LOG_INFO (
"seq=" << seq <<
" is lost because of lost flag");
953 if ((*it)->m_sacked ==
true)
955 NS_LOG_INFO (
"seq=" << seq <<
" is not lost because of sacked flag");
960 beginOfCurrentPacket += (*it)->m_packet->GetSize ();
984 PacketList::const_iterator it;
987 bool isSeqPerRule3Valid =
false;
999 NS_LOG_INFO(
"IsLost, returning" << beginOfCurrentPkt);
1000 *seq = beginOfCurrentPkt;
1004 else if (seqPerRule3.
GetValue () == 0 && isRecovery)
1006 NS_LOG_INFO (
"Saving for rule 3 the seq " << beginOfCurrentPkt);
1007 isSeqPerRule3Valid =
true;
1008 seqPerRule3 = beginOfCurrentPkt;
1033 NS_LOG_INFO (
"There is no available receiver window to send");
1048 if (isSeqPerRule3Valid)
1077 " is out of sync with sent list size " <<
m_sentSize <<
1083 " retrans: " << retrans);
1097 PacketList::const_iterator it;
1115 bool isLost =
IsLostRFC (beginOfCurrentPkt, it);
1153 "Sent size counted: " << totalSize <<
" " <<
m_sentSize << *
this);
1164 PacketList::const_iterator it;
1169 if ((*segment)->m_sacked ==
true)
1179 for (it = segment; it !=
m_sentList.end (); ++it)
1187 " found to be SACKed while checking for " << seq);
1192 NS_LOG_INFO (
"seq=" << seq <<
" is lost because of 3 sacked blocks ahead");
1202 NS_LOG_INFO (
"seq=" << seq <<
" is not lost because there are no sacked segment ahead");
1206 beginOfCurrentPacket += current->
GetSize ();
1223 (*it)->m_sacked =
false;
1298 (*it)->m_sacked =
false;
1299 (*it)->m_lost =
true;
1306 m_lostOut += (*it)->m_packet->GetSize ();
1308 else if (!(*it)->m_sacked)
1311 (*it)->m_lost =
true;
1312 m_lostOut += (*it)->m_packet->GetSize ();
1316 (*it)->m_retrans =
false;
1319 NS_LOG_INFO (
"Set sent list lost, status: " << *
this);
1404 while (it !=
m_sentList.end () && (*it)->m_sacked)
1412 (*it)->m_sacked =
true;
1415 NS_LOG_INFO (
"Added a Reno SACK, status: " << *
this);
1419 NS_LOG_INFO (
"Can't add a Reno SACK because we miss segments. This dupack"
1420 " should be arrived from spurious retransmissions");
1429 static const bool enable =
false;
1442 if ((*it)->m_sacked)
1444 sacked += (*it)->m_packet->GetSize ();
1448 lost += (*it)->m_packet->GetSize ();
1450 if ((*it)->m_retrans)
1452 retrans += (*it)->m_packet->GetSize ();
1474 TcpTxBuffer::PacketList::const_iterator it;
1475 std::stringstream ss;
1477 uint32_t sentSize = 0, appSize = 0;
1482 p = (*it)->GetPacket ();
1487 beginOfCurrentPacket += p->
GetSize ();
1492 appSize += (*it)->GetPacket ()->GetSize ();
1495 os <<
"Sent list: " << ss.str () <<
", size = " << tcpTxBuf.
m_sentList.size () <<
1496 " Total size: " << tcpTxBuf.
m_size <<
1499 " m_retransOut = " << tcpTxBuf.
m_retrans <<
1500 " m_lostOut = " << tcpTxBuf.
m_lostOut <<
bool IsNull(void) const
Check for null implementation.
A base class which provides memory management and object aggregation.
void AddAtEnd(Ptr< const Packet > packet)
Concatenate the input packet at the end of the current packet.
void RemoveAtStart(uint32_t size)
Remove size bytes from the start of the current packet.
Ptr< Packet > CreateFragment(uint32_t start, uint32_t length) const
Create a new packet which contains a fragment of the original packet.
void Print(std::ostream &os) const
Print the packet contents.
Ptr< Packet > Copy(void) const
performs a COW copy of the packet.
uint32_t GetSize(void) const
Returns the the size in bytes of the packet (including the zero-filled initial payload).
NUMERIC_TYPE GetValue() const
Extracts the numeric value of the sequence number.
static Time Now(void)
Return the current simulation virtual time.
std::list< SackBlock > SackList
SACK list definition.
uint32_t m_retrans
Number of retransmitted bytes.
void ResetRenoSack()
Reset the SACKs.
uint32_t GetSacked(void) const
Get the number of segments that have been explicitly sacked by the receiver.
void ConsistencyCheck() const
Check if the values of sacked, lost, retrans, are in sync with the sent list.
static TypeId GetTypeId(void)
Get the type ID.
bool m_sackEnabled
Indicates if SACK is enabled on this connection.
uint32_t m_lostOut
Number of lost bytes.
bool IsLostRFC(const SequenceNumber32 &seq, const PacketList::const_iterator &segment) const
Decide if a segment is lost based on RFC 6675 algorithm.
std::pair< TcpTxBuffer::PacketList::const_iterator, SequenceNumber32 > FindHighestSacked() const
Find the highest SACK byte.
std::pair< PacketList::const_iterator, SequenceNumber32 > m_highestSack
Highest SACK byte.
bool IsHeadRetransmitted() const
Check if the head is retransmitted.
bool Add(Ptr< Packet > p)
Append a data packet to the end of the buffer.
void SetSegmentSize(uint32_t segmentSize)
Set the segment size.
uint32_t Available(void) const
Returns the available capacity of this buffer.
bool IsRetransmittedDataAcked(const SequenceNumber32 &ack) const
Checks whether the ack corresponds to retransmitted data.
TcpTxItem * GetPacketFromList(PacketList &list, const SequenceNumber32 &startingSeq, uint32_t numBytes, const SequenceNumber32 &requestedSeq, bool *listEdited=nullptr) const
Get a block (which is returned as Packet) from a list.
uint32_t SizeFromSequence(const SequenceNumber32 &seq) const
Returns the number of bytes from the buffer in the range [seq, tailSequence)
TracedValue< SequenceNumber32 > m_firstByteSeq
Sequence number of the first byte in data (SND.UNA)
std::list< TcpTxItem * > PacketList
container for data stored in the buffer
TcpTxItem * GetTransmittedSegment(uint32_t numBytes, const SequenceNumber32 &seq)
Get a block of data previously transmitted.
uint32_t m_maxBuffer
Max number of data bytes in buffer (SND.WND)
bool m_renoSack
Indicates if AddRenoSack was called.
uint32_t m_dupAckThresh
Duplicate Ack threshold from TcpSocketBase.
void SetSackEnabled(bool enabled)
tell tx-buffer whether SACK is used on this TCP socket
static Callback< void, TcpTxItem * > m_nullCb
Null callback for an item.
virtual ~TcpTxBuffer(void)
uint32_t m_sackedOut
Number of sacked bytes.
void ResetLastSegmentSent()
Take the last segment sent and put it back into the un-sent list (at the beginning)
bool IsLost(const SequenceNumber32 &seq) const
Check if a segment is lost.
bool NextSeg(SequenceNumber32 *seq, SequenceNumber32 *seqHigh, bool isRecovery) const
Get the next sequence number to transmit, according to RFC 6675.
uint32_t MaxBufferSize(void) const
Get the maximum buffer size.
uint32_t GetLost(void) const
Get the number of segments that we believe are lost in the network.
void SetDupAckThresh(uint32_t dupAckThresh)
Set the DupAckThresh.
TcpTxItem * CopyFromSequence(uint32_t numBytes, const SequenceNumber32 &seq)
Copy data from the range [seq, seq+numBytes) into a packet.
TcpTxItem * GetNewSegment(uint32_t numBytes)
Get a block of data not transmitted yet and move it into SentList.
uint32_t m_segmentSize
Segment size from TcpSocketBase.
uint32_t Update(const TcpOptionSack::SackList &list, const Callback< void, TcpTxItem * > &sackedCb=m_nullCb)
Update the scoreboard.
void AddRenoSack()
Emulate SACKs for SACKless connection: account for a new dupack.
void MarkHeadAsLost()
Mark the head of the sent list as lost.
void UpdateLostCount()
Update the lost count.
SequenceNumber32 TailSequence(void) const
Get the sequence number of the buffer tail (plus one)
Callback< uint32_t > m_rWndCallback
Callback to obtain RCV.WND value.
void SetRWndCallback(Callback< uint32_t > rWndCallback)
Set callback to obtain receiver window value.
uint32_t BytesInFlight() const
Return total bytes in flight.
uint32_t Size(void) const
Returns total number of bytes in this buffer.
SequenceNumber32 HeadSequence(void) const
Get the sequence number of the buffer head.
void SetSentListLost(bool resetSack=false)
Set the entire sent list as lost (typically after an RTO)
void SplitItems(TcpTxItem *t1, TcpTxItem *t2, uint32_t size) const
Split one TcpTxItem.
void DiscardUpTo(const SequenceNumber32 &seq, const Callback< void, TcpTxItem * > &beforeDelCb=m_nullCb)
Discard data up to but not including this sequence number.
uint32_t BytesInFlightRFC() const
Calculate the number of bytes in flight per RFC 6675.
PacketList m_appList
Buffer for application data.
void MergeItems(TcpTxItem *t1, TcpTxItem *t2) const
Merge two TcpTxItem.
uint32_t m_size
Size of all data in this buffer.
void ResetSentList()
Reset the sent list.
void DeleteRetransmittedFlagFromHead()
DeleteRetransmittedFlagFromHead.
void SetMaxBufferSize(uint32_t n)
Set the maximum buffer size.
bool IsSackEnabled(void) const
check whether SACK is used on the corresponding TCP socket
PacketList m_sentList
Buffer for sent (but not acked) data.
uint32_t m_sentSize
Size of sent (and not discarded) segments.
void RemoveFromCounts(TcpTxItem *item, uint32_t size)
Remove the size specified from the lostOut, retrans, sacked count.
void SetHeadSequence(const SequenceNumber32 &seq)
Set the head sequence of the buffer.
uint32_t GetRetransmitsCount(void) const
Return the number of segments in the sent list that have been transmitted more than once,...
TcpTxBuffer(uint32_t n=0)
Constructor.
Item that encloses the application packet and some flags for it.
bool m_sacked
Indicates if the segment has been SACKed.
bool m_retrans
Indicates if the segment is retransmitted.
SequenceNumber32 m_startSeq
Sequence number of the item (if transmitted)
Time m_lastSent
Timestamp of the time at which the segment has been sent last time.
Ptr< Packet > GetPacketCopy(void) const
Get a copy of the Packet underlying this item.
bool m_lost
Indicates if the segment has been lost (RTO)
Ptr< Packet > m_packet
Application packet (can be null)
void Print(std::ostream &os, Time::Unit unit=Time::S) const
Print the time.
T Get(void) const
Get the underlying value.
a unique identifier for an interface.
TypeId SetParent(TypeId tid)
Set the parent TypeId.
#define NS_ASSERT(condition)
At runtime, in debugging builds, if this condition is not true, the program prints the source file,...
#define NS_ASSERT_MSG(condition, message)
At runtime, in debugging builds, if this condition is not true, the program prints the message to out...
#define NS_ABORT_MSG_UNLESS(cond, msg)
Abnormal program termination if a condition is false, with a message.
#define NS_FATAL_ERROR(msg)
Report a fatal error with a message and terminate.
#define NS_ABORT_MSG_IF(cond, msg)
Abnormal program termination if a condition is true, with a message.
#define NS_LOG_ERROR(msg)
Use NS_LOG to output a message of level LOG_ERROR.
#define NS_LOG_COMPONENT_DEFINE(name)
Define a Log component with a specific name.
#define NS_LOG_DEBUG(msg)
Use NS_LOG to output a message of level LOG_DEBUG.
#define NS_LOG_LOGIC(msg)
Use NS_LOG to output a message of level LOG_LOGIC.
#define NS_LOG_FUNCTION(parameters)
If log level LOG_FUNCTION is enabled, this macro will output all input parameters separated by ",...
#define NS_LOG_WARN(msg)
Use NS_LOG to output a message of level LOG_WARN.
#define NS_LOG_INFO(msg)
Use NS_LOG to output a message of level LOG_INFO.
#define NS_OBJECT_ENSURE_REGISTERED(type)
Register an Object subclass with the TypeId system.
SequenceNumber< uint32_t, int32_t > SequenceNumber32
32 bit Sequence number.
Ptr< const TraceSourceAccessor > MakeTraceSourceAccessor(T a)
Create a TraceSourceAccessor which will control access to the underlying trace source.
Every class exported by the ns3 library is enclosed in the ns3 namespace.
std::ostream & operator<<(std::ostream &os, const Angles &a)
uint32_t GetSize(Ptr< const Packet > packet, const WifiMacHeader *hdr, bool isAmpdu)
Return the total size of the packet after WifiMacHeader and FCS trailer have been added.
uint32_t pktSize
packet size used for the simulation (in bytes)