Re: [PATCH] poll: fix regression in Win32 emulation of poll function

[Bruno Haible]

Daniel P. Berrange wrote:
> Perhaps I'm mis-understanding, but I was looking at this code:
> 
>       h = (HANDLE) _get_osfhandle (pfd[i].fd);
>       assure (h != NULL);
>       if (IsSocketHandle (h))
>         {
>           int requested = FD_CLOSE;
> 
>           /* see above; socket handles are mapped onto select.  */
>           if (sought & (POLLIN | POLLRDNORM))
>             {
>               requested |= FD_READ | FD_ACCEPT;
>               FD_SET ((SOCKET) h, &rfds);
>             }
>           if (sought & (POLLOUT | POLLWRNORM | POLLWRBAND))
>             {
>               requested |= FD_WRITE | FD_CONNECT;
>               FD_SET ((SOCKET) h, &wfds);
>             }
>           if (sought & (POLLPRI | POLLRDBAND))
>             {
>               requested |= FD_OOB;
>               FD_SET ((SOCKET) h, &xfds);
>             }
> 
> which takes the 'FD' and gets the associated SOCKET / HANDLE.
> The 'xfds' fd_set is thus populated with a SOCKET, not a FD.

You're perfectly right. I misread the code. I'm applying this:


2017-05-11 Bruno Haible  <br...@clisp.org>

        poll: Fix confusion between SOCKETs and FDs on native Windows.
        Fix proposed by Daniel P. Berrange <berra...@redhat.com>.
        * lib/poll.c [WINDOWS_NATIVE]: Undefine select.

diff --git a/lib/poll.c b/lib/poll.c
index c4b2127..818a2cd 100644
--- a/lib/poll.c
+++ b/lib/poll.c
@@ -80,6 +80,10 @@
    first argument, not any possible gnulib override.  */
 # undef recv
 
+/* Here we need the select() function from Windows, because we pass bit masks
+   of SOCKETs, not bit masks of FDs.  */
+# undef select
+
 static BOOL IsConsoleHandle (HANDLE h)
 {
   DWORD mode;