[gstreamer-bugs] [Bug 533619] New: udpsink dies when Linux fails (for no reason) sendto() with non-posix errno

[GStreamer (bugzilla.gnome.org)]

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  GStreamer | gst-plugins-good | Ver: 0.10.x
           Summary: udpsink dies when Linux fails (for no reason) sendto()
                    with non-posix errno
           Product: GStreamer
           Version: 0.10.x
          Platform: Other
        OS/Version: All
            Status: UNCONFIRMED
          Severity: normal
          Priority: Normal
         Component: gst-plugins-good
        AssignedTo: gstreamer-bugs at lists.sourceforge.net
        ReportedBy: g.rantila at gmail.com
         QAContact: gstreamer-bugs at lists.sourceforge.net
     GNOME version: 2.21/2.22
   GNOME milestone: Unspecified


Please describe the problem:
I don't know why, perhaps it is when my firewall-scripts (using
iptables/netfilter) are restarting, Linux fails udp sendto() and sets errno to
EPERM, which is NOT conforming to POSIX. This errno shouldn't be used for
sendto().
I've tried to see why this happens, but found nothing wrong in the udp
implementation in Linux, but the IO syscalls are filtered in a rather messy way
in Linux, to "secure" syscalls, for instance with SELinux (which I am NOT using
btw).
Well, EPERM is set anyway, and I'm using a plain vanilla kernel.

The problem is, when this happens, the stream dies. I'm streaming over network
to a set-top-box connected to my TV. When sendto() fails, this is not
visible/noticeable, so to just ignore the few hundred (at most) failing
sendto()'s is fine, whenever it happens.

The attached patches fixes this issue, by ignoring sendo() failures where errno
is non-POSIX EPERM.
The 'talking' patch prints a warning the first time this happens.
The 'silent' patch just fixes the problem.

Please use any of the patches (preferably the silent one).

Steps to reproduce:
1. Run Linux and make sure it sets errno to EPERM (don't ask me how)
2. Use udpsink


Actual results:
Stream dies

Expected results:
I don't really know what to expect when Linux doesn't conform to POSIX, but
reasonably "try as good as you can". This patch makes sure udpsink really
tries.

Does this happen every time?
Yes

Other information:


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