/// <summary>
///
/// </summary>
/// <param name="items"> (must not be null)</param>
/// <param name="itemsCount"></param>
/// <param name="timeout">a time-out period, in milliseconds</param>
/// <returns></returns>
/// <exception cref="FaultException">items must not be null, or the internal call to Select failed</exception>
public bool Select(SelectItem[] items, int itemsCount, int timeout)
{
if (items == null)
{
throw new FaultException("Selector.Select called with items equal to null.");
}
if (itemsCount == 0)
{
if (timeout == 0)
return false;
//TODO: Do we really want to simply sleep and return, doing nothing during this interval?
Thread.Sleep(timeout);
return false;
}
bool firstPass = true;
int numberOfEvents = 0;
Stopwatch stopwatch = null;
while (true)
{
int currentTimeoutMicroSeconds;
if (firstPass)
{
currentTimeoutMicroSeconds = 0;
}
else if (timeout == -1)
{
currentTimeoutMicroSeconds = -1;
}
else
{
currentTimeoutMicroSeconds = (int)((timeout - stopwatch.ElapsedMilliseconds) * 1000);
if (currentTimeoutMicroSeconds < 0)
{
currentTimeoutMicroSeconds = 0;
}
}
m_checkRead.Clear();
m_checkWrite.Clear();
m_checkError.Clear();
for (int i = 0; i < itemsCount; i++)
{
var pollItem = items[i];
if (pollItem.Socket != null)
{
if (pollItem.Event != PollEvents.None && pollItem.Socket.Handle.Connected)
{
m_checkRead.Add(pollItem.Socket.Handle);
}
}
else
{
if ((pollItem.Event & PollEvents.PollIn) == PollEvents.PollIn)
{
m_checkRead.Add(pollItem.FileDescriptor);
}
if ((pollItem.Event & PollEvents.PollOut) == PollEvents.PollOut)
{
m_checkWrite.Add(pollItem.FileDescriptor);
}
}
}
try
{
SocketUtility.Select(m_checkRead, m_checkWrite, m_checkError, currentTimeoutMicroSeconds);
}
catch (SocketException x)
{
#if DEBUG
string textOfListRead = StringLib.AsString(m_checkRead);
string textOfListWrite = StringLib.AsString(m_checkWrite);
string textOfListError = StringLib.AsString(m_checkError);
string xMsg = string.Format("In Selector.Select, Socket.Select({0}, {1}, {2}, {3}) threw a SocketException: {4}", textOfListRead, textOfListWrite, textOfListError, currentTimeoutMicroSeconds, x.Message);
Debug.WriteLine(xMsg);
throw new FaultException(innerException: x, message: xMsg);
#else
throw new FaultException(innerException: x, message: "Within SocketUtility.Select");
#endif
}
for (int i = 0; i < itemsCount; i++)
{
var selectItem = items[i];
selectItem.ResultEvent = PollEvents.None;
if (selectItem.Socket != null)
{
PollEvents events = (PollEvents)selectItem.Socket.GetSocketOption(ZmqSocketOptions.Events);
if ((selectItem.Event & PollEvents.PollIn) == PollEvents.PollIn && (events & PollEvents.PollIn) == PollEvents.PollIn)
{
selectItem.ResultEvent |= PollEvents.PollIn;
}
if ((selectItem.Event & PollEvents.PollOut) == PollEvents.PollOut &&
(events & PollEvents.PollOut) == PollEvents.PollOut)
{
selectItem.ResultEvent |= PollEvents.PollOut;
}
}
else
{
if (m_checkRead.Contains(selectItem.FileDescriptor))
{
selectItem.ResultEvent |= PollEvents.PollIn;
}
if (m_checkWrite.Contains(selectItem.FileDescriptor))
{
selectItem.ResultEvent |= PollEvents.PollOut;
}
}
if (selectItem.ResultEvent != PollEvents.None)
{
numberOfEvents++;
}
}
if (timeout == 0)
{
break;
}
if (numberOfEvents > 0)
{
break;
}
if (timeout < 0)
{
if (firstPass)
{
firstPass = false;
}
continue;
}
if (firstPass)
{
stopwatch = Stopwatch.StartNew();
firstPass = false;
continue;
}
if (stopwatch.ElapsedMilliseconds > timeout)
{
break;
}
}
return numberOfEvents > 0;
}
private void RebuildPollset()
{
m_pollSize = m_sockets.Count + m_pollinSockets.Count;
// Recreate the m_pollset and m_pollact arrays.
m_pollset = new SelectItem[m_pollSize];
m_pollact = new NetMQSocket[m_sockets.Count];
// For each socket in m_sockets,
// put a corresponding SelectItem into the m_pollset array and a reference to the socket itself into the m_pollact array.
uint itemNbr = 0;
foreach (var socket in m_sockets)
{
m_pollset[itemNbr] = new SelectItem(socket.SocketHandle, socket.GetPollEvents());
m_pollact[itemNbr] = socket;
itemNbr++;
}
foreach (var socket in m_pollinSockets)
{
m_pollset[itemNbr] = new SelectItem(socket.Key, PollEvents.PollError | PollEvents.PollIn);
itemNbr++;
}
// Mark this as NOT having any fresh events to attend to, as yet.
m_isDirty = false;
}
