Similar to de30de865cd, this allows to follow the flow of events as they
arrive to a pad rather than only when they are pushed to a peer.
The hook is installed in gst_pad_send_event_unchecked() instead of
gst_pad_send_event() because the latter is often omitted: that is the
case especifically in gst_pad_push_event_unchecked(), where most event
propagation occurs.
This patch also makes use of the new hooks in the log tracer to log the
begining and end of the send_event processing.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/8330>
Previously, the tracer pad-push-event was only signalled on
gst_pad_push_event(). However, the sticky event handling code in
GStreamer uses gst_pad_push_event_unchecked() instead, which meant those
events were not logged.
This patch extends the definition of the pad-push-event tracer to cover
both calls to gst_pad_push_event() and any direct calls to
gst_pad_push_event_unchecked() that skip the former inside GstPad
private code.
gst_pad_push_event_unchecked() returns GstFlowReturn instead of
gboolean like gst_pad_push_event(). To maintain API compatibility, the
GstFlowReturn is converted to gboolean.
Fixes https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/4182
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/8342>
In the case where the bufferlist is writable, send the
buffers immediately without adding to the refcount. This
allows writable buffers to maintain their writability, even
without implementing a chain_list function on the element.
Adds a test to verify this property, where a writable list
maintains refcount 1, but a readonly list increases it.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/7894>
FLUSH_STOP is meant to clear the flushing state of pads and elements
downstream, not to process data. Hence, a FLUSH_STOP should not
propagate sticky events. This is also consistent with how flushes are a
special case for probes.
Currently this is almost always the case, since a FLUSH_STOP is
__usually__ preceded by a FLUSH_START, and events (sticky or not) are
discarded while a pad has the FLUSHING flag active (set by FLUSH_START).
However, it is currently assumed that a FLUSH_STOP not preceded by a
FLUSH_START is correct behavior, and this will occur while autoplugging
pipelines are constructed. This leaves us with an unhandled edge case!
This patch explicitly disables sending sticky events when pushing a
FLUSH_STOP, instead of relying on the flushing flag of the pad, which
will break in the edge case of a FLUSH_STOP not preceded by a
FLUSH_START.
If sticky events are propagated in response to a FLUSH_STOP, the
flushing thread can end up deadlocked in blocking code of a downstream
pad, such as a blocking probe. Instead, those events should be
propagated from the streaming thread of the pad when handling a
non-flushing synchronized event or buffer.
This fixes a deadlock found in WebKit with playbin3 when seeks occur
before preroll, where the seeking thread ended up stuck in the blocking
probe of playsink:
https://github.com/WebPlatformForEmbedded/WPEWebKit/issues/1367
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/7632>
This commit makes sure that pads are valid for linking
after the pads has been temporarily unlocked in the linking process.
Not doing this opens up for a race condition where
pads potentially can be linked twice.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5670>
When the task already exists, we forgot to free the passed `user_data`.
This wasn't an issue for most C code, which doesn't pass a
`GDestroyNotify`, but bindings such as gstreamer-rs do!
That said, allocating a trampoline in gstreamer-rs just for it to get
thrown away again is awkward. Maybe we need a `gst_pad_resume_task`?
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3920>
The event type for instant-rate-change events was poorly chosen,
leading to them being re-sent too late and even after EOS.
Add a mechanism in GstPad for the sticky event order to be
different to the value of the event type to fix that up.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3387>
The scenario is the following:
* Thread 1 is pushing an EOS event on a sinkpad
* Thread 2 is pushing a STREAM_START event on the same sinkpad before Thread 1
returns. Note : It starts pushing the event after Thread 1 took the object lock.
There is a potential race between:
* The moment Thread 1 sets the EOS flag once it has finished sending the
event (via store_sticky_event). When it does that it has both the STREAM and
OBJECT lock
* The moment Thread 2 sends the STREAM_START event (Which should release that
EOS status), but removing the EOS flag is only done while holding the OBJECT
lock and not the STREAM_LOCK, which means it could be re-set by Thread 1 before
it then checks again the EOS flag (without the STREAM lock taken).
The EOS flag unsetting by STREAM_START should be done with the STREAM lock
taken, otherwise it will be racy.
Fixes https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/1452
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3320>
With non-serialized sticky events, such as GST_EVENT_INSTANT_RATE, we both want
to store the event (for later re-linking) *AND* push the event in a non-blocking
way.
We therefore must *not* propagate pending sticky events if the event is "sticky
or serialized" but only if it's "serialized"
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3254>
