[Bug 10032] New: Wine must not use unix select() for networking where there might be high fd's

http://bugs.winehq.org/show_bug.cgi?id=10032

Summary: Wine must not use unix select() for networking where
                    there might be high fd's
           Product: Wine
           Version: CVS/GIT
          Platform: Other
        OS/Version: other
            Status: NEW
          Keywords: patch
          Severity: normal
          Priority: P2
         Component: wine-net
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]

select() cannot handle fds higher than FD_SETSIZE.
Thus if you open a lot of plain old files, then 
create one socket and try to use a networking function
based on select(), you're hosed.

This actually happened recently during soak testing of an app doing
lots of wininet stuff, which tickled a socket leak
in wininet (see
http://winehq.org/pipermail/wine-patches/2007-October/045089.html
for the leak fix).  This was a wake-up call for us; the
app in question is fine after the leak fix, but an app
that really used lots of file descriptors would hit the bug 
in a bad way.

Here's how to find all the suspicious calls to select():
$ find . -name '*.c' | xargs grep '[^a-z]select[^a-zA-Z]*(.*&' | grep -v
'/tests/'
Calls where select is used with no fd's are ok, since they can't run into the
problem.  Calls which use a winsock select() instead of a unix select()
might be ok (e.g. netapi32/nbt.c), since winsock's select doesn't
have a fixed FD_SETSIZE.  Only two problematic calls remain:

wininet/internet.c:        if (select(nSocket+1,&infd,NULL,NULL,&tv) > 0)
wininet/netconnection.c:     if
(select(connection->socketFD+1,&infd,NULL,NULL,&tv) > 0)

These must be replaced with poll(), which can handle high fd's.

This was discussed last November,
 http://www.winehq.org/pipermail/wine-devel/2006-November/052099.html
and Damjan submitted patches to fix them:
http://www.winehq.org/pipermail/wine-patches/2006-November/032529.html
http://www.winehq.org/pipermail/wine-patches/2006-November/032530.html
but these patches don't seem to have been applied yet.  Time to get them in!

[Bug 10032] Wine must not use unix select() for networking where there might be high fd's

http://bugs.winehq.org/show_bug.cgi?id=10032

Dan Kegel  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |1.0.0

--- Comment #1 from Dan Kegel   2007-10-14 11:18:59 ---
This is a 1.0 must-fix bug.

[Bug 10032] Wine must not use unix select() for networking where there might be high fd's

http://bugs.winehq.org/show_bug.cgi?id=10032

Damjan Jovanovic  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |[e-mail]

--- Comment #2 from Damjan Jovanovic   2007-10-15 00:39:42 ---
I believe the complication with wininet's select() was that if you use poll()
instead, you can't compile a native DLL with mingw.

[Bug 10032] Wine must not use unix select() for networking where there might be high fd's

http://bugs.winehq.org/show_bug.cgi?id=10032

--- Comment #3 from Dan Kegel   2007-11-25 23:48:26 ---
Why do we care if you can build a wininet.dll with mingw?

[Bug 10032] Wine must not use unix select() for networking where there might be high fd's

http://bugs.winehq.org/show_bug.cgi?id=10032

--- Comment #4 from Damjan Jovanovic   2007-11-25 23:56:30 ---
It makes it possible to use wine's DLLs on Windows for testing and such.
Wininet already supports being built with mingw, it would be a shame to lose
that. My patches got mingw building with both wine and mingw (I had #ifdef
sections which use poll on Linux and select on Windows), but for some reason
they weren't accepted.

[Bug 10032] Wine must not use unix select() for networking where there might be high fd's

http://bugs.winehq.org/show_bug.cgi?id=10032

--- Comment #5 from Dan Kegel   2007-11-26 06:08:09 ---
Thanks for the explanation.

Would you consider resubmitting without the #ifdef's,
and maintaining the mingw compatibility patch out of tree?

[Bug 10032] Wine must not use unix select() for networking where there might be high fd's

http://bugs.winehq.org/show_bug.cgi?id=10032

Steven Edwards  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |[e-mail]

--- Comment #6 from Steven Edwards   2007-12-19 06:21:02 ---
> Would you consider resubmitting without the #ifdef's,
> and maintaining the mingw compatibility patch out of tree?

-1 on maintaining compatibility patches out of the tree. I spent a lot of time
getting wininet working and building mingw/msvc and this amounts to throwing
away my work. It can and should be fixed for both cases.

[Bug 10032] Wine must not use unix select() for networking where there might be high fd's

http://bugs.winehq.org/show_bug.cgi?id=10032

--- Comment #7 from Alexandre Julliard   2007-12-19 13:15:26 ---
There's no reason to clutter up the code with #ifdefs. It's easy to provide a
poll() substitute in libport for Mingw.

[Bug 10032] Wine must not use unix select() for networking where there might be high fd's

http://bugs.winehq.org/show_bug.cgi?id=10032

Kai Blin  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED

--- Comment #8 from Kai Blin   2008-03-24 07:13:11 ---
Patch sent.

[Bug 10032] Wine must not use unix select() for networking where there might be high fd's

http://bugs.winehq.org/show_bug.cgi?id=10032

Kai Blin  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED

--- Comment #9 from Kai Blin   2008-03-24 09:21:25 ---
Committed in 63504e9e80acb35666f8689526c67dd99c4fb3ba

[Bug 10032] Wine must not use unix select() for networking where there might be high fd's

http://bugs.winehq.org/show_bug.cgi?id=10032

Alexandre Julliard  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |CLOSED

--- Comment #10 from Alexandre Julliard   2008-04-04 10:06:03 ---
Closing bugs fixed in 0.9.59.

[Bug 10032] Wine must not use unix select() for networking where there might be high fd's

http://bugs.winehq.org/show_bug.cgi?id=10032

Austin English  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
            Version|CVS/GIT                     |unspecified