public int getLostSeq()
{
if (0 == m_iLength)
{
return(-1);
}
lock (m_ListLock)
{
if (0 == m_iLength)
{
return(-1);
}
if (m_iLastInsertPos == m_iHead)
{
m_iLastInsertPos = -1;
}
// return the first loss seq. no.
int seqno = m_piData1[m_iHead];
// head moves to the next node
if (-1 == m_piData2[m_iHead])
{
//[3, -1] becomes [], and head moves to next node in the list
m_piData1[m_iHead] = -1;
m_iHead = m_piNext[m_iHead];
}
else
{
// shift to next node, e.g., [3, 7] becomes [], [4, 7]
int loc = (m_iHead + 1) % m_iSize;
m_piData1[loc] = SequenceNumber.incseq(seqno);
if (SequenceNumber.seqcmp(m_piData2[m_iHead], m_piData1[loc]) > 0)
{
m_piData2[loc] = m_piData2[m_iHead];
}
m_piData1[m_iHead] = -1;
m_piData2[m_iHead] = -1;
m_piNext[loc] = m_piNext[m_iHead];
m_iHead = loc;
}
m_iLength--;
return(seqno);
}
}
public void insert(int seqno1, int seqno2)
{
// Data to be inserted must be larger than all those in the list
// guaranteed by the UDT receiver
if (0 == m_iLength)
{
// insert data into an empty list
m_iHead = 0;
m_iTail = 0;
m_piData1[m_iHead] = seqno1;
if (seqno2 != seqno1)
{
m_piData2[m_iHead] = seqno2;
}
m_piNext[m_iHead] = -1;
m_piPrior[m_iHead] = -1;
m_iLength += SequenceNumber.seqlen(seqno1, seqno2);
return;
}
// otherwise searching for the position where the node should be
int offset = SequenceNumber.seqoff(m_piData1[m_iHead], seqno1);
int loc = (m_iHead + offset) % m_iSize;
if ((-1 != m_piData2[m_iTail]) && (SequenceNumber.incseq(m_piData2[m_iTail]) == seqno1))
{
// coalesce with prior node, e.g., [2, 5], [6, 7] becomes [2, 7]
loc = m_iTail;
m_piData2[loc] = seqno2;
}
else
{
// create new node
m_piData1[loc] = seqno1;
if (seqno2 != seqno1)
{
m_piData2[loc] = seqno2;
}
m_piNext[m_iTail] = loc;
m_piPrior[loc] = m_iTail;
m_piNext[loc] = -1;
m_iTail = loc;
}
m_iLength += SequenceNumber.seqlen(seqno1, seqno2);
}
public bool remove(int seqno)
{
if (0 == m_iLength)
{
return(false);
}
// locate the position of "seqno" in the list
int offset = SequenceNumber.seqoff(m_piData1[m_iHead], seqno);
if (offset < 0)
{
return(false);
}
int loc = (m_iHead + offset) % m_iSize;
if (seqno == m_piData1[loc])
{
// This is a seq. no. that starts the loss sequence
if (-1 == m_piData2[loc])
{
// there is only 1 loss in the sequence, delete it from the node
if (m_iHead == loc)
{
m_iHead = m_piNext[m_iHead];
if (-1 != m_iHead)
{
m_piPrior[m_iHead] = -1;
}
}
else
{
m_piNext[m_piPrior[loc]] = m_piNext[loc];
if (-1 != m_piNext[loc])
{
m_piPrior[m_piNext[loc]] = m_piPrior[loc];
}
else
{
m_iTail = m_piPrior[loc];
}
}
m_piData1[loc] = -1;
}
else
{
// there are more than 1 loss in the sequence
// move the node to the next and update the starter as the next loss inSeqNo(seqno)
// find next node
int j = (loc + 1) % m_iSize;
// remove the "seqno" and change the starter as next seq. no.
m_piData1[j] = SequenceNumber.incseq(m_piData1[loc]);
// process the sequence end
if (SequenceNumber.seqcmp(m_piData2[loc], SequenceNumber.incseq(m_piData1[loc])) > 0)
{
m_piData2[j] = m_piData2[loc];
}
// remove the current node
m_piData1[loc] = -1;
m_piData2[loc] = -1;
// update list pointer
m_piNext[j] = m_piNext[loc];
m_piPrior[j] = m_piPrior[loc];
if (m_iHead == loc)
{
m_iHead = j;
}
else
{
m_piNext[m_piPrior[j]] = j;
}
if (m_iTail == loc)
{
m_iTail = j;
}
else
{
m_piPrior[m_piNext[j]] = j;
}
}
m_iLength--;
return(true);
}
// There is no loss sequence in the current position
// the "seqno" may be contained in a previous node
// searching previous node
int i = (loc - 1 + m_iSize) % m_iSize;
while (-1 == m_piData1[i])
{
i = (i - 1 + m_iSize) % m_iSize;
}
// not contained in this node, return
if ((-1 == m_piData2[i]) || (SequenceNumber.seqcmp(seqno, m_piData2[i]) > 0))
{
return(false);
}
if (seqno == m_piData2[i])
{
// it is the sequence end
if (seqno == SequenceNumber.incseq(m_piData1[i]))
{
m_piData2[i] = -1;
}
else
{
m_piData2[i] = SequenceNumber.decseq(seqno);
}
}
else
{
// split the sequence
// construct the second sequence from SequenceNumber.incseq(seqno) to the original sequence end
// located at "loc + 1"
loc = (loc + 1) % m_iSize;
m_piData1[loc] = SequenceNumber.incseq(seqno);
if (SequenceNumber.seqcmp(m_piData2[i], m_piData1[loc]) > 0)
{
m_piData2[loc] = m_piData2[i];
}
// the first (original) sequence is between the original sequence start to SequenceNumber.decseq(seqno)
if (seqno == SequenceNumber.incseq(m_piData1[i]))
{
m_piData2[i] = -1;
}
else
{
m_piData2[i] = SequenceNumber.decseq(seqno);
}
// update the list pointer
m_piNext[loc] = m_piNext[i];
m_piNext[i] = loc;
m_piPrior[loc] = i;
if (m_iTail == i)
{
m_iTail = loc;
}
else
{
m_piPrior[m_piNext[loc]] = loc;
}
}
m_iLength--;
return(true);
}
int insert_unsafe(int seqno1, int seqno2)
{
if (0 == m_iLength)
{
// insert data into an empty list
m_iHead = 0;
m_piData1[m_iHead] = seqno1;
if (seqno2 != seqno1)
{
m_piData2[m_iHead] = seqno2;
}
m_piNext[m_iHead] = -1;
m_iLastInsertPos = m_iHead;
m_iLength += SequenceNumber.seqlen(seqno1, seqno2);
return(m_iLength);
}
// otherwise find the position where the data can be inserted
int origlen = m_iLength;
int offset = SequenceNumber.seqoff(m_piData1[m_iHead], seqno1);
int loc = (m_iHead + offset + m_iSize) % m_iSize;
if (offset < 0)
{
// Insert data prior to the head pointer
m_piData1[loc] = seqno1;
if (seqno2 != seqno1)
{
m_piData2[loc] = seqno2;
}
// new node becomes head
m_piNext[loc] = m_iHead;
m_iHead = loc;
m_iLastInsertPos = loc;
m_iLength += SequenceNumber.seqlen(seqno1, seqno2);
}
else if (offset > 0)
{
if (seqno1 == m_piData1[loc])
{
m_iLastInsertPos = loc;
// first seqno is equivlent, compare the second
if (-1 == m_piData2[loc])
{
if (seqno2 != seqno1)
{
m_iLength += SequenceNumber.seqlen(seqno1, seqno2) - 1;
m_piData2[loc] = seqno2;
}
}
else if (SequenceNumber.seqcmp(seqno2, m_piData2[loc]) > 0)
{
// new seq pair is longer than old pair, e.g., insert [3, 7] to [3, 5], becomes [3, 7]
m_iLength += SequenceNumber.seqlen(m_piData2[loc], seqno2) - 1;
m_piData2[loc] = seqno2;
}
else
{
// Do nothing if it is already there
return(0);
}
}
else
{
// searching the prior node
int i;
if ((-1 != m_iLastInsertPos) && (SequenceNumber.seqcmp(m_piData1[m_iLastInsertPos], seqno1) < 0))
{
i = m_iLastInsertPos;
}
else
{
i = m_iHead;
}
while ((-1 != m_piNext[i]) && (SequenceNumber.seqcmp(m_piData1[m_piNext[i]], seqno1) < 0))
{
i = m_piNext[i];
}
if ((-1 == m_piData2[i]) || (SequenceNumber.seqcmp(m_piData2[i], seqno1) < 0))
{
m_iLastInsertPos = loc;
// no overlap, create new node
m_piData1[loc] = seqno1;
if (seqno2 != seqno1)
{
m_piData2[loc] = seqno2;
}
m_piNext[loc] = m_piNext[i];
m_piNext[i] = loc;
m_iLength += SequenceNumber.seqlen(seqno1, seqno2);
}
else
{
m_iLastInsertPos = i;
// overlap, coalesce with prior node, insert(3, 7) to [2, 5], ... becomes [2, 7]
if (SequenceNumber.seqcmp(m_piData2[i], seqno2) < 0)
{
m_iLength += SequenceNumber.seqlen(m_piData2[i], seqno2) - 1;
m_piData2[i] = seqno2;
loc = i;
}
else
{
return(0);
}
}
}
}
else
{
m_iLastInsertPos = m_iHead;
// insert to head node
if (seqno2 != seqno1)
{
if (-1 == m_piData2[loc])
{
m_iLength += SequenceNumber.seqlen(seqno1, seqno2) - 1;
m_piData2[loc] = seqno2;
}
else if (SequenceNumber.seqcmp(seqno2, m_piData2[loc]) > 0)
{
m_iLength += SequenceNumber.seqlen(m_piData2[loc], seqno2) - 1;
m_piData2[loc] = seqno2;
}
else
{
return(0);
}
}
else
{
return(0);
}
}
// coalesce with next node. E.g., [3, 7], ..., [6, 9] becomes [3, 9]
while ((-1 != m_piNext[loc]) && (-1 != m_piData2[loc]))
{
int i = m_piNext[loc];
if (SequenceNumber.seqcmp(m_piData1[i], SequenceNumber.incseq(m_piData2[loc])) <= 0)
{
// coalesce if there is overlap
if (-1 != m_piData2[i])
{
if (SequenceNumber.seqcmp(m_piData2[i], m_piData2[loc]) > 0)
{
if (SequenceNumber.seqcmp(m_piData2[loc], m_piData1[i]) >= 0)
{
m_iLength -= SequenceNumber.seqlen(m_piData1[i], m_piData2[loc]);
}
m_piData2[loc] = m_piData2[i];
}
else
{
m_iLength -= SequenceNumber.seqlen(m_piData1[i], m_piData2[i]);
}
}
else
{
if (m_piData1[i] == SequenceNumber.incseq(m_piData2[loc]))
{
m_piData2[loc] = m_piData1[i];
}
else
{
m_iLength--;
}
}
m_piData1[i] = -1;
m_piData2[i] = -1;
m_piNext[loc] = m_piNext[i];
}
else
{
break;
}
}
return(m_iLength - origlen);
}
void remove_unsafe(int seqno)
{
if (0 == m_iLength)
{
return;
}
// Remove all from the head pointer to a node with a larger seq. no. or the list is empty
int offset = SequenceNumber.seqoff(m_piData1[m_iHead], seqno);
int loc = (m_iHead + offset + m_iSize) % m_iSize;
if (0 == offset)
{
// It is the head. Remove the head and point to the next node
loc = (loc + 1) % m_iSize;
if (-1 == m_piData2[m_iHead])
{
loc = m_piNext[m_iHead];
}
else
{
m_piData1[loc] = SequenceNumber.incseq(seqno);
if (SequenceNumber.seqcmp(m_piData2[m_iHead], SequenceNumber.incseq(seqno)) > 0)
{
m_piData2[loc] = m_piData2[m_iHead];
}
m_piData2[m_iHead] = -1;
m_piNext[loc] = m_piNext[m_iHead];
}
m_piData1[m_iHead] = -1;
if (m_iLastInsertPos == m_iHead)
{
m_iLastInsertPos = -1;
}
m_iHead = loc;
m_iLength--;
}
else if (offset > 0)
{
int h = m_iHead;
if (seqno == m_piData1[loc])
{
// target node is not empty, remove part/all of the seqno in the node.
int temp = loc;
loc = (loc + 1) % m_iSize;
if (-1 == m_piData2[temp])
{
m_iHead = m_piNext[temp];
}
else
{
// remove part, e.g., [3, 7] becomes [], [4, 7] after remove(3)
m_piData1[loc] = SequenceNumber.incseq(seqno);
if (SequenceNumber.seqcmp(m_piData2[temp], m_piData1[loc]) > 0)
{
m_piData2[loc] = m_piData2[temp];
}
m_iHead = loc;
m_piNext[loc] = m_piNext[temp];
m_piNext[temp] = loc;
m_piData2[temp] = -1;
}
}
else
{
// target node is empty, check prior node
int i = m_iHead;
while ((-1 != m_piNext[i]) && (SequenceNumber.seqcmp(m_piData1[m_piNext[i]], seqno) < 0))
{
i = m_piNext[i];
}
loc = (loc + 1) % m_iSize;
if (-1 == m_piData2[i])
{
m_iHead = m_piNext[i];
}
else if (SequenceNumber.seqcmp(m_piData2[i], seqno) > 0)
{
// remove part/all seqno in the prior node
m_piData1[loc] = SequenceNumber.incseq(seqno);
if (SequenceNumber.seqcmp(m_piData2[i], m_piData1[loc]) > 0)
{
m_piData2[loc] = m_piData2[i];
}
m_piData2[i] = seqno;
m_piNext[loc] = m_piNext[i];
m_piNext[i] = loc;
m_iHead = loc;
}
else
{
m_iHead = m_piNext[i];
}
}
// Remove all nodes prior to the new head
while (h != m_iHead)
{
if (m_piData2[h] != -1)
{
m_iLength -= SequenceNumber.seqlen(m_piData1[h], m_piData2[h]);
m_piData2[h] = -1;
}
else
{
m_iLength--;
}
m_piData1[h] = -1;
if (m_iLastInsertPos == h)
{
m_iLastInsertPos = -1;
}
h = m_piNext[h];
}
}
}