private void PingElapsed(object sender, NetMQTimerEventArgs e)
{
Assumes.NotNull(m_transmit);
SendUdpFrame(m_transmit);
}
private void Configure(string interfaceName, int port)
{
Assumes.NotNull(m_poller);
Assumes.NotNull(m_pipe);
// In case the beacon was configured twice
if (m_udpSocket != null)
{
m_poller.Remove(m_udpSocket);
#if NET35
m_udpSocket.Close();
#else
m_udpSocket.Dispose();
#endif
}
m_udpPort = port;
m_udpSocket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
m_poller.Add(m_udpSocket, OnUdpReady);
// Ask operating system for broadcast permissions on socket
m_udpSocket.EnableBroadcast = true;
// Allow multiple owners to bind to socket; incoming
// messages will replicate to each owner
m_udpSocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);
IPAddress?bindTo = null;
IPAddress?sendTo = null;
if (interfaceName == "*")
{
bindTo = IPAddress.Any;
sendTo = IPAddress.Broadcast;
}
else if (interfaceName == "loopback")
{
bindTo = IPAddress.Loopback;
sendTo = IPAddress.Broadcast;
}
else
{
var interfaceCollection = new InterfaceCollection();
var interfaceAddress = !string.IsNullOrEmpty(interfaceName)
? IPAddress.Parse(interfaceName)
: null;
foreach (var @interface in interfaceCollection)
{
if (interfaceAddress == null || @interface.Address.Equals(interfaceAddress))
{
// because windows and unix differ in how they handle broadcast addressing this needs to be platform specific
// on windows any interface can receive broadcast by requesting to enable broadcast on the socket
// on linux to receive broadcast you must bind to the broadcast address specifically
//bindTo = @interface.Address;
sendTo = @interface.BroadcastAddress;
#if NET45 || NET47_OR_GREATER
if (Environment.OSVersion.Platform == PlatformID.Unix)
#else
if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
#endif
{
bindTo = @interface.BroadcastAddress;
}
else
{
bindTo = @interface.Address;
}
sendTo = @interface.BroadcastAddress;
break;
}
}
}
if (bindTo != null)
{
m_broadcastAddress = new IPEndPoint(sendTo, m_udpPort);
m_udpSocket.Bind(new IPEndPoint(bindTo, m_udpPort));
}
m_pipe.SendFrame(bindTo?.ToString() ?? "");
}
/// <summary>
/// Runs the poller on the caller's thread. Only returns when <see cref="Stop"/> or <see cref="StopAsync"/> are called from another thread.
/// </summary>
private void RunPoller()
{
try
{
// Recalculate all timers now
foreach (var timer in m_timers)
{
if (timer.Enable)
{
timer.When = Clock.NowMs() + timer.Interval;
}
}
// Run until stop is requested
while (!m_stopSignaler.IsStopRequested)
{
if (m_isPollSetDirty)
{
RebuildPollset();
}
var pollStart = Clock.NowMs();
// Set tickless to "infinity"
long tickless = pollStart + int.MaxValue;
// Find the When-value of the earliest timer..
foreach (var timer in m_timers)
{
// If it is enabled but no When is set yet,
if (timer.When == -1 && timer.Enable)
{
// Set this timer's When to now plus it's Interval.
timer.When = pollStart + timer.Interval;
}
// If it has a When and that is earlier than the earliest found thus far,
if (timer.When != -1 && tickless > timer.When)
{
// save that value.
tickless = timer.When;
}
}
// Compute a timeout value - how many milliseconds from now that the earliest-timer will expire.
var timeout = tickless - pollStart;
// Use zero to indicate it has already expired.
if (timeout < 0)
{
timeout = 0;
}
var isItemAvailable = false;
Assumes.NotNull(m_pollSet);
if (m_pollSet.Length != 0)
{
isItemAvailable = m_netMqSelector.Select(m_pollSet, m_pollSet.Length, timeout);
}
else if (timeout > 0)
{
//TODO: Do we really want to simply sleep and return, doing nothing during this interval?
//TODO: Should a large value be passed it will sleep for a month literally.
// Solution should be different, but sleep is more natural here than in selector (timers are not selector concern).
Debug.Assert(timeout <= int.MaxValue);
Thread.Sleep((int)timeout);
}
// Get the expected end time in case we time out. This looks redundant but, unfortunately,
// it happens that Poll takes slightly less than the requested time and 'Clock.NowMs() >= timer.When'
// may not true, even if it is supposed to be. In other words, even when Poll times out, it happens
// that 'Clock.NowMs() < pollStart + timeout'
var expectedPollEnd = !isItemAvailable ? pollStart + timeout : -1L;
// that way we make sure we can continue the loop if new timers are added.
// timers cannot be removed
foreach (var timer in m_timers)
{
if ((Clock.NowMs() >= timer.When || expectedPollEnd >= timer.When) && timer.When != -1)
{
timer.InvokeElapsed(this);
if (timer.Enable)
{
timer.When = Clock.NowMs() + timer.Interval;
}
}
}
for (var i = 0; i < m_pollSet.Length; i++)
{
NetMQSelector.Item item = m_pollSet[i];
if (item.Socket != null)
{
Assumes.NotNull(m_pollact);
NetMQSocket socket = m_pollact[i];
if (item.ResultEvent.HasError())
{
if (++socket.Errors > 1)
{
Remove(socket);
item.ResultEvent = PollEvents.None;
}
}
else
{
socket.Errors = 0;
}
if (item.ResultEvent != PollEvents.None)
{
socket.InvokeEvents(this, item.ResultEvent);
}
}
else if (item.ResultEvent.HasError() || item.ResultEvent.HasIn())
{
Assumes.NotNull(item.FileDescriptor);
if (m_pollinSockets.TryGetValue(item.FileDescriptor, out Action <Socket> action))
{
action(item.FileDescriptor);
}
}
}
}
#if !NET35
// Try to dequeue and execute all pending tasks before stopping poller
while (m_tasksQueue.TryDequeue(out Task? task, TimeSpan.Zero))
{
TryExecuteTask(task);
}
#endif
}
finally
{
foreach (var socket in m_sockets.ToList())
{
Remove(socket);
}
}
}
