/// <summary>
/// Write packet header into
/// <paramref name="pkt"/>
/// ,
/// return the length of the header written.
/// </summary>
private int WritePacketHeader(ByteBuffer pkt, int dataLen, int packetLen)
{
pkt.Clear();
// both syncBlock and syncPacket are false
PacketHeader header = new PacketHeader(packetLen, offset, seqno, (dataLen == 0),
dataLen, false);
int size = header.GetSerializedSize();
pkt.Position(PacketHeader.PktMaxHeaderLen - size);
header.PutInBuffer(pkt);
return(size);
}
/// <summary>Write the full packet, including the header, to the given output stream.
/// </summary>
/// <param name="stm"/>
/// <exception cref="System.IO.IOException"/>
internal virtual void WriteTo(DataOutputStream stm)
{
lock (this)
{
CheckBuffer();
int dataLen = dataPos - dataStart;
int checksumLen = checksumPos - checksumStart;
int pktLen = HdfsConstants.BytesInInteger + dataLen + checksumLen;
PacketHeader header = new PacketHeader(pktLen, offsetInBlock, seqno, lastPacketInBlock
, dataLen, syncBlock);
if (checksumPos != dataStart)
{
// Move the checksum to cover the gap. This can happen for the last
// packet or during an hflush/hsync call.
System.Array.Copy(buf, checksumStart, buf, dataStart - checksumLen, checksumLen);
checksumPos = dataStart;
checksumStart = checksumPos - checksumLen;
}
int headerStart = checksumStart - header.GetSerializedSize();
System.Diagnostics.Debug.Assert(checksumStart + 1 >= header.GetSerializedSize());
System.Diagnostics.Debug.Assert(headerStart >= 0);
System.Diagnostics.Debug.Assert(headerStart + header.GetSerializedSize() == checksumStart
);
// Copy the header data into the buffer immediately preceding the checksum
// data.
System.Array.Copy(header.GetBytes(), 0, buf, headerStart, header.GetSerializedSize
());
// corrupt the data for testing.
if (DFSClientFaultInjector.Get().CorruptPacket())
{
buf[headerStart + header.GetSerializedSize() + checksumLen + dataLen - 1] ^= unchecked (
(int)(0xff));
}
// Write the now contiguous full packet to the output stream.
stm.Write(buf, headerStart, header.GetSerializedSize() + checksumLen + dataLen);
// undo corruption.
if (DFSClientFaultInjector.Get().UncorruptPacket())
{
buf[headerStart + header.GetSerializedSize() + checksumLen + dataLen - 1] ^= unchecked (
(int)(0xff));
}
}
}
