Crash in GstBaseSink on EOF

[Marko Mikkonen]

I'm developing a custom source plugin on Windows using MinGW and I'm 
experiencing a crash at EOF event in GstBaseSink. My pipeline looks like 
this:

my_source_plugin ! decodebin2 ! directsoundsink

My source plugin is essentially outputting an mp3 file. The sound comes 
out without problems. At the end of file gstreamer goes to wait for the 
playing to stop (afaik, on the basis that I've understood from debugging 
these files). Then in gst_poll_wait, in the switch-case block 
"GST_POLL_MODE_WINDOWS", WSAWaitForMultipleEvents is called with zero 
event handle count and null event array pointer as arguments. The 
function doesn't seem to like something and crashes. I can't debug any 
further, because it's a Windows kernel function. I haven't found any 
documentation which would say anything about the case when these 
arguments are zero so I don't know if this is the real problem (but I 
feel like it is).

I'm not sure what my plugin is doing wrong. Maybe it's sending a wrong 
length of media or something, but I still think GstBaseSink should not 
crash in this case.

The traceback of the crash point looks like this:

Thread [8] 0 (Suspended : Breakpoint)
Crash somewhere in here ->    WSAWaitForMultipleEvents()
     gst_poll_wait() at gstpoll.c:1 376 0x6b7016a7
     gst_system_clock_id_wait_jitter_unlocked() at gstsystemclock.c:619 
0x6b712a91
     gst_clock_id_wait() at gstclock.c:467 0x6b6d4fe8
     gst_base_sink_wait_clock() at gstbasesink.c:2 129 0x6caca295
     gst_base_sink_wait_eos() at gstbasesink.c:2 324 0x6cad1283
     gst_base_audio_sink_drain() at gstbaseaudiosink.c:866 0x7068853e
     gst_base_audio_sink_event() at gstbaseaudiosink.c:894 0x7068deaf
     gst_base_sink_render_object() at gstbasesink.c:2 908 0x6caca790
     gst_base_sink_queue_object_unlocked() at gstbasesink.c:3 156 
0x6cacfcae
     gst_base_sink_event() at gstbasesink.c:3 315 0x6cad0905
     gst_pad_send_event() at gstpad.c:5 365 0x6b6f645d
     gst_pad_push_event() at gstpad.c:5 217 0x6b6f6a15
     gst_base_transform_sink_event() at gstbasetransform.c:1 956 0x6cadb27a
     gst_pad_send_event() at gstpad.c:5 365 0x6b6f645d
     gst_pad_push_event() at gstpad.c:5 217 0x6b6f6a15
     gst_pad_send_event() at gstpad.c:5 365 0x6b6f645d
     gst_pad_push_event() at gstpad.c:5 217 0x6b6f6a15
     gst_pad_send_event() at gstpad.c:5 365 0x6b6f645d
     gst_pad_push_event() at gstpad.c:5 217 0x6b6f6a15
     gst_pad_send_event() at gstpad.c:5 365 0x6b6f645d
<...more frames...>

The last function, WSAWaitForMultipleEvents, is called like this:

         wait_ret = WSAWaitForMultipleEvents (set->active_events->len,
             (HANDLE *) set->active_events->data, FALSE, t, FALSE);

Here set->active_events->len and set->active_events->data are both null. 
Variable t has some value (about 100-300, it varies).

I have compiled everything myself and the gstreamer package is 
gstreamer-0.10.32. I don't know how else to clarify this situation. You 
can email me and ask for the values of variables in any of the functions 
in the stack, if you need them.

The question is of course: What is the problem and how to fix it?

-Marko