// Functionality:
// Read a block of data from file and insert it into the sending list.
// Parameters:
// 0) [in] ifs: input file stream.
// 1) [in] len: size of the block.
// Returned value:
// actual size of data added from the file.
public int addBufferFromFile(Stream ifs, int len)
{
int size = len / m_iMSS;
if ((len % m_iMSS) != 0)
size++;
// dynamically increase sender buffer
while (size + m_iCount >= m_iSize)
increase();
Block s = m_pLastBlock;
int total = 0;
for (int i = 0; i < size; ++i)
{
if (ifs.bad() || ifs.fail() || ifs.eof())
break;
int pktlen = len - i * m_iMSS;
if (pktlen > m_iMSS)
pktlen = m_iMSS;
ifs.Read(s.m_pcData, 0, pktlen);
if ((pktlen = ifs.gcount()) <= 0)
break;
s.m_iLength = pktlen;
s.m_iTTL = -1;
s = s.m_pNext;
total += pktlen;
}
m_pLastBlock = s;
lock (m_BufLock)
{
m_iCount += size;
}
return total;
}
