/// <summary>
/// WaitForMessage - have the server wait for a message
/// </summary>
/// <returns>a non-null MessageStream if it got a message, null if timed out or error
/// </returns>
public MemoryStream WaitForMessage()
{
bool fullyRead = false;
string errMsg = "";
int errCode = 0;
// They want to talk to us, read their messages and write replies
MemoryStream receiveStream = new MemoryStream();
byte[] buffer = new byte[_receiveBufferSize];
byte[] _numReadWritten = new byte[4];
// Need to read the whole message and put it in one message byte buffer
do
{
// Read the response from the pipe
if (!NamedPipeInterop.ReadFile(
_handle, // Pipe handle
buffer, // Buffer to receive reply
(uint)_receiveBufferSize, // Size of buffer
_numReadWritten, // Number of bytes read
0)) // Not overlapped
{
// Failed, not just more data to come
errCode = Marshal.GetLastWin32Error( );
if (errCode != NamedPipeInterop.ERROR_MORE_DATA)
{
break;
}
else
{
errMsg = string.Format("Could not read from pipe with error {0}", errCode);
Trace.WriteLine(errMsg);
throw new Win32Exception(errCode, errMsg);
}
}
else
{
// We succeeded and no more data is coming
fullyRead = true;
}
// Concat the message bytes to the stream
receiveStream.Write(buffer, 0, buffer.Length);
} while (!fullyRead);
// Return the message we received if any
if (receiveStream.Length > 0)
{
return(receiveStream);
}
else // Didn't receive anything
{
return(null);
}
}
/// <summary>
/// CreatePipe - create the named pipe
/// </summary>
/// <returns>true is pipe created</returns>
public bool CreatePipe()
{
// Make a named pipe in message mode
_handle = NamedPipeInterop.CreateNamedPipe(_pipeName,
NamedPipeInterop.PIPE_ACCESS_DUPLEX,
NamedPipeInterop.PIPE_TYPE_MESSAGE | NamedPipeInterop.PIPE_READMODE_MESSAGE | NamedPipeInterop.PIPE_WAIT,
NamedPipeInterop.PIPE_UNLIMITED_INSTANCES,
PIPE_SERVER_BUFFER_SIZE,
PIPE_SERVER_BUFFER_SIZE,
NamedPipeInterop.NMPWAIT_WAIT_FOREVER,
IntPtr.Zero);
// Make sure we got a good one
if (_handle.IsInvalid)
{
Debug.WriteLine("Could not create the pipe (" + _pipeName + ") - os returned " + Marshal.GetLastWin32Error());
return(false);
}
return(true);
}
/// <summary>
/// WaitForClientConnect - wait for a client to connect to this pipe
/// </summary>
/// <returns>true if connected, false if timed out</returns>
public bool WaitForClientConnect()
{
// Wait for someone to talk to us.
return(NamedPipeInterop.ConnectNamedPipe(_handle, IntPtr.Zero));
}