/// <summary>
/// Convert a message to a packet using packet length and specific header
/// </summary>
/// <param name="messageData">The message data to convert.</param>
/// <param name="offset">The offset of the message data.</param>
/// <param name="count">The count of bytes to convert.</param>
/// <param name="sendBuffer">The send buffer which is associated with each connection. It is used to avoid allocating memory every time.</param>
/// <returns>The packed byte array segment with length and header tag if UseMakePacket property is true; otherwise the input message data with doing nothing.</returns>
public ArraySegment <byte> MakePacket(byte[] messageData, int offset, int count, DynamicBufferStream sendBuffer)
{
Contract.Assert(messageData != null && count > 0);
if (!UseMakePacket)
{
return(new ArraySegment <byte>(messageData, offset, count));
}
int dataLen = count;
int packetLen = dataLen;
if (UseNetworkByteOrder)
{
packetLen = IPAddress.HostToNetworkOrder(dataLen);
}
sendBuffer.SetLength(8 + dataLen);
//write header
Buffer.BlockCopy(BitConverter.GetBytes(_headerTag), 0, sendBuffer.Buffer, 0, 4);
//write message length
Buffer.BlockCopy(BitConverter.GetBytes(packetLen), 0, sendBuffer.Buffer, 4, 4);
if (dataLen > 0)
{
Buffer.BlockCopy(messageData, offset, sendBuffer.Buffer, 8, dataLen);
}
return(new ArraySegment <byte>(sendBuffer.Buffer, 0, (int)sendBuffer.Length));
}
/// <summary>
/// Convert a message to a packet using end mark.
/// </summary>
/// <param name="messageData">The message data to convert.</param>
/// <param name="offset">The offset of the message data.</param>
/// <param name="count">The count of bytes to convert.</param>
/// <param name="sendBuffer">The send buffer which is associated with each connection. It is used to avoid allocating memory every time.</param>
/// <returns>The packed byte array segment with end mark if UseMakePacket property is true; otherwise the input message data with doing nothing.</returns>
public ArraySegment <byte> MakePacket(byte[] messageData, int offset, int count, DynamicBufferStream sendBuffer)
{
Contract.Requires(messageData != null && messageData.Length > 0);
if (!UseMakePacket)
{
return(new ArraySegment <byte>(messageData, offset, count));
}
sendBuffer.SetLength(count + _endMark.Length);
//write data
Buffer.BlockCopy(messageData, offset, sendBuffer.Buffer, 0, count);
//write end mark
Buffer.BlockCopy(_endMark, 0, sendBuffer.Buffer, count, _endMark.Length);
return(new ArraySegment <byte>(sendBuffer.Buffer, 0, (int)sendBuffer.Length));
}
