[socket] Add EPROTOTYPE error case (#4391)

Fixes bug https://bugzilla.xamarin.com/show_bug.cgi?id=52549

mcs/class/System/Test/System.Net.Sockets/SocketTest.cs

@@ -4675,6 +4675,29 @@ namespace MonoTests.System.Net.Sockets
 
 			Assert.IsTrue (mre.WaitOne (1000), "ConnectedAsync timeout");
 		}
+
+		[Test] // Covers https://bugzilla.xamarin.com/show_bug.cgi?id=52549
+#if FEATURE_NO_BSD_SOCKETS
+		[ExpectedException (typeof (PlatformNotSupportedException))]
+#endif
+		public void SocketMismatchProtocol ()
+		{
+			try {
+				using (Socket socket = new Socket (AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Tcp));
+				Assert.Fail ("#1");
+			} catch (SocketException e) {
+				// Only work on OSX
+				// Assert.AreEqual(SocketError.ProtocolType, e.SocketErrorCode, "#2");
+			}
+
+			try {
+				using (Socket socket = new Socket (AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Udp));
+				Assert.Fail ("#3");
+			} catch (SocketException e) {
+				// Only work on OSX
+				// Assert.AreEqual(SocketError.ProtocolType, e.SocketErrorCode, "#4");
+			}
+		}
  	}
 }
 

mono/metadata/w32error.h

@@ -52,6 +52,7 @@
 #define WSAENOTSOCK                10038
 #define WSAEDESTADDRREQ            10039
 #define WSAEMSGSIZE                10040
+#define WSAEPROTOTYPE              10041
 #define WSAENOPROTOOPT             10042
 #define WSAEPROTONOSUPPORT         10043
 #define WSAESOCKTNOSUPPORT         10044

mono/metadata/w32socket-unix.c

@@ -1318,6 +1318,9 @@ mono_w32socket_convert_error (gint error)
 	case ENETDOWN: return WSAENETDOWN;
 #endif
 	case ENODEV: return WSAENETDOWN;
+#ifdef EPROTOTYPE
+	case EPROTOTYPE: return WSAEPROTOTYPE;
+#endif
 	default:
 		g_error ("%s: no translation into winsock error for (%d) \"%s\"", __func__, error, g_strerror (error));
 	}