/// <summary>
/// Continue receiving body
/// </summary>
public void ContinueReceivingBody(byte[] buffer, int offset, int length)
{
//NOTE::
//need to call this method many times until all body receive complete
_toBeReceiveData = new SocketReceiveState(buffer, offset, length);
beginReceiveData(_toBeReceiveData);
}
/// <summary>
/// receive data callback
/// </summary>
/// <param name="result"></param>
private void receiveDataCallback(IAsyncResult result)
{
SocketReceiveState receiveState = (SocketReceiveState)result.AsyncState;
int recByte = 0;
try
{
recByte = _workingSocket.EndReceive(result);
receiveState.Offset += recByte;
if (!_isReceivingHeader)
{
_receivingProgress.Completed += recByte;
}
}
catch (Exception ex)
{
onClose(ex);
return;
}
if (recByte > 0)
{
try
{
analyzeData(receiveState);
}
catch (Exception ex)
{
onClose(ex);
return;
}
}
else
{
onClose(new AsyncSocketException("Connection has been closed"));
}
}
/// <summary>
/// Begin receive data
/// </summary>
/// <param name="header"></param>
/// <param name="buffer"></param>
/// <param name="offset"></param>
/// <param name="length"></param>
public void Receive(IProtocolHeader header, byte[] buffer, int offset, int length)
{
//the buffer length must large than TRANSFER_BLOCK_LENGTH
if (buffer.Length - offset < TRANSFER_BLOCK_LENGTH ||
length < TRANSFER_BLOCK_LENGTH)
{
throw new ArgumentException("Buffer length must large than TRANSFER_BLOCK_LENGTH");
}
if (_isClosing)
{
throw new AsyncSocketException("Connection has closed");
}
_lastReceiveHeader = header;
_toBeReceiveData = new SocketReceiveState(buffer, offset, length);
_receivingProgress.Reset();
SocketReceiveState receiveState = new SocketReceiveState(
_headerBuffer, 0, _headerBuffer.Length);
beginReceiveData(receiveState);
}
/// <summary>
/// begin receive data
/// </summary>
private void beginReceiveData(SocketReceiveState receiveState)
{
try
{
//calculate the length need to be receive at this time
int receiveByte = receiveState.Length - (receiveState.Offset - receiveState.StartIndex);
if (receiveByte > TRANSFER_BLOCK_LENGTH)
{
receiveByte = TRANSFER_BLOCK_LENGTH;
}
_workingSocket.BeginReceive(
receiveState.Data,
receiveState.Offset,
receiveByte,
SocketFlags.None,
new AsyncCallback(receiveDataCallback),
receiveState);
}
catch (Exception ex)
{
onClose(ex);
}
}
/// <summary>
/// analyze the received data
/// </summary>
/// <param name="receiveState"></param>
private void analyzeData(SocketReceiveState receiveState)
{
//a flag to indicate whether the header/body has received complete
bool receiveCompleted = true;
if (_isReceivingHeader)
{
//seek the split-symbol between the header and body
int position = seekSplitSymbolPosition(receiveState.Data, receiveState.Offset);
if (position < 0)
{
//continue receive header
receiveCompleted = false;
if (receiveState.Offset >= HEADER_BUFFER_LENGTH)
{
onClose(new AsyncSocketException("Header data overflow"));
return;
}
}
else
{
//parse the header string
//byte[] headerData = new byte[position];
//Buffer.BlockCopy(receiveState.Data, 0, headerData, 0, headerData.Length);
//_lastReceiveHeader.HeaderRawData = headerData;
_lastReceiveHeader.SetHeaderRawData(receiveState.Data, 0, position);
//raise ReceiveHeaderComplete event
ReceiveHeaderCompleteEventArgs arg = new ReceiveHeaderCompleteEventArgs(_lastReceiveHeader);
try
{
ReceiveHeaderComplete(this, arg);
//NOTE::
//here, caller must specify the "arg.TotalPlanReceivingLength" value,
//to indicate whether continue receive body or not
}
catch (Exception ex)
{
onClose(ex);
return;
}
if (arg.TotalPlanReceivingLength > 0)
{
//need receive body
_isReceivingHeader = false;
_receivingProgress.Total = arg.TotalPlanReceivingLength;
//check this data whether it contains partial body
int tailLength = receiveState.Offset - position - 4;
if (tailLength > 0)
{
Buffer.BlockCopy(receiveState.Data, position + 4,
_toBeReceiveData.Data, _toBeReceiveData.Offset, tailLength);
_toBeReceiveData.Offset += tailLength;
_receivingProgress.Completed = tailLength;
}
//replace the receive state object
receiveState = _toBeReceiveData;
}
}
}
//to judge if the body has receive complete
if (!_isReceivingHeader)
{
if (receiveState.Offset - receiveState.StartIndex < receiveState.Length &&
_receivingProgress.Completed < _receivingProgress.Total)
{
//not complete yet
receiveCompleted = false;
}
else
{
//receive body complete
if (_receivingProgress.Completed >= _receivingProgress.Total)
{
//all body receive complete, reset this flag
_isReceivingHeader = true;
}
//raise the ReceiveBodyComplete event
ReceiveBodyCompleteEventArgs arg = new ReceiveBodyCompleteEventArgs(
_lastReceiveHeader,
receiveState.Data,
receiveState.Offset,
receiveState.StartIndex,
_receivingProgress.Completed,
_receivingProgress.Total);
try
{
ReceiveBodyComplete(this, arg);
}
catch (Exception ex)
{
onClose(ex);
return;
}
}
}
//continue to receiving header or body data
if (!receiveCompleted)
{
beginReceiveData(receiveState);
}
}