private static void GetDevicesFromSocket(IPEndPoint multicastIPEndpoint, IProgress <Device> deviceFoundCallback, Socket ssdpSocket, Dictionary <string, Device> devices)
{
ssdpSocket.SendTo(
Encoding.ASCII.GetBytes(string.Format(DeviceLocator._ssdpMessage, multicastIPEndpoint.Address)),
SocketFlags.None,
multicastIPEndpoint
);
var stopWatch = Stopwatch.StartNew();
try
{
while (stopWatch.Elapsed < TimeSpan.FromSeconds(1))
{
try // Catch socket read exception
{
int available = ssdpSocket.Available;
if (available > 0)
{
var buffer = new byte[available];
int numberOfBytesRead = ssdpSocket.Receive(buffer, SocketFlags.None);
if (numberOfBytesRead > 0)
{
string response = Encoding.UTF8.GetString(buffer.Take(numberOfBytesRead).ToArray());
Device device = DeviceLocator.GetDeviceInformationFromSsdpMessage(response);
if (!devices.ContainsKey(device.Hostname))
{
devices.Add(device.Hostname, device);
deviceFoundCallback?.Report(device);
}
}
}
}
catch (SocketException)
{
// Ignore SocketException and continue polling
}
Thread.Sleep(TimeSpan.FromMilliseconds(10));
}
}
finally
{
stopWatch.Stop();
}
}
private static List <Task <List <Device> > > CreateDiscoverTasks(NetworkInterface netInterface, int retryCount)
{
var devices = new ConcurrentDictionary <string, Device>();
var tasks = new List <Task <List <Device> > >();
if (netInterface.NetworkInterfaceType != NetworkInterfaceType.Wireless80211 &&
netInterface.NetworkInterfaceType != NetworkInterfaceType.Ethernet)
{
return(tasks);
}
foreach (UnicastIPAddressInformation ip in netInterface.GetIPProperties().UnicastAddresses)
{
if (ip.Address.AddressFamily != AddressFamily.InterNetwork)
{
continue;
}
for (var count = 0; count < retryCount; count++)
{
Task <List <Device> > t = Task.Run(
async() =>
{
var stopWatch = new Stopwatch();
try
{
using (var ssdpSocket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp)
{
Blocking = false,
Ttl = 1,
UseOnlyOverlappedIO = true,
MulticastLoopback = false
})
{
ssdpSocket.Bind(new IPEndPoint(ip.Address, 0));
ssdpSocket.SetSocketOption(
SocketOptionLevel.IP,
SocketOptionName.AddMembership,
new MulticastOption(DeviceLocator._multicastEndPoint.Address));
ssdpSocket.SendTo(
DeviceLocator._ssdpDiagram,
SocketFlags.None,
DeviceLocator._multicastEndPoint);
stopWatch.Start();
while (stopWatch.Elapsed < TimeSpan.FromSeconds(1))
{
try
{
int available = ssdpSocket.Available;
if (available > 0)
{
var buffer = new byte[available];
int i = ssdpSocket.Receive(buffer, SocketFlags.None);
if (i > 0)
{
string response = Encoding.UTF8.GetString(buffer.Take(i).ToArray());
Device device = DeviceLocator.GetDeviceInformationFromSsdpMessage(response);
//add only if no device already matching
if (devices.TryAdd(device.Hostname, device))
{
DeviceLocator.OnDeviceFound?.Invoke(null, new DeviceFoundEventArgs(device));
}
}
}
}
catch (SocketException)
{
// Continue polling
}
await Task.Delay(TimeSpan.FromMilliseconds(10));
}
stopWatch.Stop();
}
}
catch (SocketException)
{
return(devices.Values.ToList());
}
finally
{
stopWatch.Stop();
}
return(devices.Values.ToList());
});
tasks.Add(t);
}
}
return(tasks);
}