public override int insert(Int32 seqno1, Int32 seqno2)
{
CGuard listguard = new CGuard(m_ListLock);
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 += CSeqNo.seqlen(seqno1, seqno2);
return m_iLength;
}
// otherwise find the position where the data can be inserted
int origlen = m_iLength;
int offset = CSeqNo.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 += CSeqNo.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 += CSeqNo.seqlen(seqno1, seqno2) - 1;
m_piData2[loc] = seqno2;
}
}
else if (CSeqNo.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 += CSeqNo.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) && (CSeqNo.seqcmp(m_piData1[m_iLastInsertPos], seqno1) < 0))
i = m_iLastInsertPos;
else
i = m_iHead;
while ((-1 != m_piNext[i]) && (CSeqNo.seqcmp(m_piData1[m_piNext[i]], seqno1) < 0))
i = m_piNext[i];
if ((-1 == m_piData2[i]) || (CSeqNo.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 += CSeqNo.seqlen(seqno1, seqno2);
}
else
{
m_iLastInsertPos = i;
// overlap, coalesce with prior node, insert(3, 7) to [2, 5], ... becomes [2, 7]
if (CSeqNo.seqcmp(m_piData2[i], seqno2) < 0)
{
m_iLength += CSeqNo.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 += CSeqNo.seqlen(seqno1, seqno2) - 1;
m_piData2[loc] = seqno2;
}
else if (CSeqNo.seqcmp(seqno2, m_piData2[loc]) > 0)
{
m_iLength += CSeqNo.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 (CSeqNo.seqcmp(m_piData1[i], CSeqNo.incseq(m_piData2[loc])) <= 0)
{
// coalesce if there is overlap
if (-1 != m_piData2[i])
{
if (CSeqNo.seqcmp(m_piData2[i], m_piData2[loc]) > 0)
{
if (CSeqNo.seqcmp(m_piData2[loc], m_piData1[i]) >= 0)
m_iLength -= CSeqNo.seqlen(m_piData1[i], m_piData2[loc]);
m_piData2[loc] = m_piData2[i];
}
else
m_iLength -= CSeqNo.seqlen(m_piData1[i], m_piData2[i]);
}
else
{
if (m_piData1[i] == CSeqNo.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;
}