Fix different behavior for Mono framework.

dotnet · May 18, 2024 · 1d1a4c7 · 1d1a4c7
1 parent 1afcf3c
commit 1d1a4c7
Showing 1 changed file with 21 additions and 2 deletions.
diff --git a/Source/MQTTnet/Implementations/CrossPlatformSocket.cs b/Source/MQTTnet/Implementations/CrossPlatformSocket.cs
@@ -202,9 +202,28 @@ public async Task ConnectAsync(EndPoint endPoint, CancellationToken cancellation
                 using (cancellationToken.Register(_socketDisposeAction))
                 {
 #if NET452 || NET461
-                    await Task.Factory.FromAsync(_socket.BeginConnect, _socket.EndConnect, endPoint, null).ConfigureAwait(false);
+                    // This is a fix for Mono which behaves differently than dotnet.
+                    // The connection will not be established when the DNS endpoint is used.
+                    if (endPoint is DnsEndPoint dns && dns.AddressFamily == AddressFamily.Unspecified)
+                    {
+                        await Task.Factory.FromAsync(_socket.BeginConnect, _socket.EndConnect, dns.Host, dns.Port, null).ConfigureAwait(false);
+                    }
+                    else
+                    {
+                        await Task.Factory.FromAsync(_socket.BeginConnect, _socket.EndConnect, endPoint, null).ConfigureAwait(false);
+                    }
 #else
-                    await _socket.ConnectAsync(endPoint).ConfigureAwait(false);
+
+                    // This is a fix for Mono which behaves differently than dotnet.
+                    // The connection will not be established when the DNS endpoint is used.
+                    if (endPoint is DnsEndPoint dns && dns.AddressFamily == AddressFamily.Unspecified)
+                    {
+                        await _socket.ConnectAsync(dns.Host, dns.Port).ConfigureAwait(false);
+                    }
+                    else
+                    {
+                        await _socket.ConnectAsync(endPoint).ConfigureAwait(false);
+                    }
 #endif
                 }
 #endif