/// <summary>
/// Writes the message to a memory mapped file, where the memory mapped file name is WebsocketPipe.Address + id.
/// mmf format: [wasread? 1 byte][datasize(int)][length(int)][msg][length(int)][msg]...
/// If wasread=0, then writes the new message to the end of the message list and advances the number of messages +1.
/// If wasread=1, clears the mmf and then writes the new message.
/// </summary>
/// <param name="wp">The calling WebsocketPipe</param>
/// <param name="msg">The message to write.</param>
/// <param name="to">The stream to write the mmf filename to.</param>
/// <param name="id">The id of the targer we are writing to, since there may be many we open a mmf for each</param>
public virtual void WriteMessage(WebsocketPipeMessageInfo msg, Stream to)
{
if (msg.Data.Length < this.UseInternalPacketDataSendingIfMsgByteSizeIsLessThen)
{
// write that this is an internal message.
to.WriteByte(1);
WebsocketAsInternalDataSocket.WriteMessage(msg, to);
return;
}
// write that this is a mmf msg.
to.WriteByte(0);
// make the id and write it to the stream.
string id = MakeValidMmfID(msg.DataSocketId);
byte[] mmfnamebuffer = ASCIIEncoding.ASCII.GetBytes(id);
to.Write(mmfnamebuffer, 0, mmfnamebuffer.Length);
Mutex mu = new Mutex(false, id + "_mutex");
if (!mu.WaitOne(MemoryMappedFileAccessTimeout))
{
throw new Exception("Memory mapped file access timedout.");
}
// The data size for a single message.
int totalDataSize = msg.Data.Length + sizeof(int) + 1;
// Creating/Opening the stream.
MemoryMappedViewStream strm = GetDataWritingMemoryMappedViewStream(id, ref totalDataSize);
// we are at the position of the write, and are ready for the message write.
msg.WriteToStream(strm);
strm.Flush();
strm.Close();
strm.Dispose();
strm = null;
// release the mutex.
mu.ReleaseMutex();
}
public virtual void WriteMessage(WebsocketPipeMessageInfo msg, Stream to)
{
msg.WriteToStream(to);
}
