[glib: 1/2] Windows: fix FD_READ condition flag still set on recoverable UDP socket errors.

[Sebastian Dröge <sdroege src gnome org>]

commit 43b13d7a1ac1170394fdaef1bc628d84ee747f60
Author: Marco Mastropaolo <marco mastropaolo com>
Date:   Thu Dec 24 09:08:40 2020 +0000

    Windows: fix FD_READ condition flag still set on recoverable UDP socket errors.
    
    Contrary to what the WSARecvFrom seem to imply, a UDP socket is perfectly recoverable and usable after a 
WSAECONNRESET error (and, I assume, WSAENETRESET).
    However GSocket condition has the FD_READ bit set after a UDP socket fails with WSAECONNRESET, even if no 
data is available on the socket anymore; this causes select calls to report the socket as readable when, in 
fact, it's not.
    
    The change resets FD_READ flag on a socket upon the above error conditions; there's no 'if' to filter 
between datagram and stream sockets as the change should be harmless in the case of stream sockets which are, 
however, very unlikely to be usable after a WSAECONNRESET.

 gio/gsocket.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gio/gsocket.c b/gio/gsocket.c
index 0f8f9259f..e911de781 100644
--- a/gio/gsocket.c
+++ b/gio/gsocket.c
@@ -5475,10 +5475,10 @@ g_socket_receive_message_with_timeout (GSocket                 *socket,
            if (errsv == WSAEINTR)
              continue;
 
+           win32_unset_event_mask (socket, FD_READ);
+
             if (errsv == WSAEWOULDBLOCK)
               {
-                win32_unset_event_mask (socket, FD_READ);
-
                 if (timeout_us != 0)
                   {
                     if (!block_on_timeout (socket, G_IO_IN, timeout_us,