Unified to throw NotSupportedException when SendFile() for connectionless sockets (#87108)

* Unified to throw NotSupportedException when SendFile() for connectionless sockets

The issue was that the Socket.SendFile() threw inconsistent exceptions when the platform was Windows and the protocol was UDP.
The first call would throw a SocketException, while the second call would throw a NotSupportedException.

With this commit, SendFile() will consistently throw NotSupportException on all platforms when the protocol is UDP.

Fix #47472

* Change to throws `NotSupportedException` if `!IsConnectionOriented` or `!Connected`.

Before:.

    Throws `NotSupportedException` on UDP.

After:

    Throws `NotSupportedException` if `!IsConnectionOriented` or `!Connected`.

* Changed test case `UdpConnection_ThrowsException` to run regardless of platform.

* Update src/libraries/System.Net.Sockets/src/System/Net/Sockets/Socket.Tasks.cs

Co-authored-by: Karel Zikmund <[email protected]>

---------

Co-authored-by: Karel Zikmund <[email protected]>

Author: rhirano0715

src/libraries/System.Net.Sockets/src/System/Net/Sockets/Socket.Tasks.cs

@@ -749,8 +749,8 @@ public ValueTask SendFileAsync(string? fileName, ReadOnlyMemory<byte> preBuffer,
 
             if (!IsConnectionOriented)
             {
-                var soex = new SocketException((int)SocketError.NotConnected);
-                return ValueTask.FromException(soex);
+                var ex = new NotSupportedException(SR.net_notconnected);
+                return ValueTask.FromException(ex);
             }
 
             int packetsCount = 0;

src/libraries/System.Net.Sockets/src/System/Net/Sockets/Socket.cs

@@ -1258,7 +1258,7 @@ public void SendFile(string? fileName, ReadOnlySpan<byte> preBuffer, ReadOnlySpa
         {
             ThrowIfDisposed();
 
-            if (!Connected)
+            if (!IsConnectionOriented || !Connected)
             {
                 throw new NotSupportedException(SR.net_notconnected);
             }

src/libraries/System.Net.Sockets/tests/FunctionalTests/SendFile.cs

@@ -62,7 +62,6 @@ public async Task FileDoesNotExist_ThrowsFileNotFoundException(bool useOverloadW
         [Theory]
         [InlineData(false)]
         [InlineData(true)]
-        [PlatformSpecific(TestPlatforms.Windows)]
         public async Task UdpConnection_ThrowsException(bool usePreAndPostbufferOverload)
         {
             // Create file to send
@@ -77,16 +76,14 @@ public async Task UdpConnection_ThrowsException(bool usePreAndPostbufferOverload
 
             client.Connect(listener.LocalEndPoint);
 
-            SocketException ex;
             if (usePreAndPostbufferOverload)
             {
-                ex = await Assert.ThrowsAsync<SocketException>(() => SendFileAsync(client, tempFile.Path, Array.Empty<byte>(), Array.Empty<byte>(), TransmitFileOptions.UseDefaultWorkerThread));
+                await Assert.ThrowsAsync<NotSupportedException>(() => SendFileAsync(client, tempFile.Path, Array.Empty<byte>(), Array.Empty<byte>(), TransmitFileOptions.UseDefaultWorkerThread));
             }
             else
             {
-                ex = await Assert.ThrowsAsync<SocketException>(() => SendFileAsync(client, tempFile.Path));
+                await Assert.ThrowsAsync<NotSupportedException>(() => SendFileAsync(client, tempFile.Path));
             }
-            Assert.Equal(SocketError.NotConnected, ex.SocketErrorCode);
         }
 
         public static IEnumerable<object[]> SendFile_MemberData()