This might create deadlocks and we need to avoid holding element
specific lock while posting messages
For example a deadlock will happen if while posting the message,
someone connected on the bus (sync) tries to DOT the pipeline.
https://bugzilla.gnome.org/show_bug.cgi?id=737102
It might cause deadlocks to post messages while holding the queue2
lock. To avoid this a new boolean flag is set whenever a new
buffering percent is found. The message is posted after the lock
is released.
To make sure the buffering messages are posted in the right order, messages
are posted holding another lock. This prevents 2 threads trying to post
messages at the same time.
https://bugzilla.gnome.org/show_bug.cgi?id=736969
It might cause deadlocks to post messages while holding the multiqueue
lock. To avoid this a new boolean flag is set whenever a new buffering percent
is found. The message is posted after the lock can be released.
To make sure the buffering messages are posted in the right order, messages
are posted holding another lock. This prevents 2 threads trying to post
messages at the same time.
https://bugzilla.gnome.org/show_bug.cgi?id=736295
Don't re-start the queue push task on the source pad when a
flush-stop event comes in and we're in the process of shutting
down, otherwise that task will never be stopped again.
When the element is set to READY state, the pads get de-activated.
The source pad gets deactivated before the queue's own activate_mode
function on the source pads gets called (which will stop the thread),
so checking whether the pad is active before re-starting the task on
receiving flush-stop should be fine. The problem would happen when the
flush-stop handler was called just after the queue's activate mode
function had stopped the task.
Spotted and debugged by Linus Svensson <linux.svensson@axis.com>
https://bugzilla.gnome.org/show_bug.cgi?id=734688
Otherwise it would only be proxied for the active pad which can lead
upstream to use an incompatible caps for the downstream element.
Even if a reconfigure event is sent upstream when the pad is activated, this
will save the caps reconfiguration if it is already using an acceptable caps.
Imagine the following 'pipeline'
--------------
p1/| 'fullqueue' |--- 'laggy' downstream
--------- / | |
-| demuxer | | multiqueue |
--------- \ | |
p2\| 'emptyqueue' |--- 'fast' downstream
--------------
In the case downstream of one single queue (fullqueue) has (a lot of) latency
(for example for reverse playback with video), we can end up having the other
SingleQueue (emptyqueue) emptied, before that fullqueue gets
unblocked. In the meantime, the demuxer tries to push on fullqueue, and
is blocking there.
In that case the current code will post a BUFFERING message on the bus when
emptyqueue gets emptied, that leads to the application setting the pipeline state to
PAUSED. So now we end up in a situation where 'laggy downstream' is
prerolled and will not unblock anymore because the pipeline is set to
PAUSED, the fullequeue does not have a chance to be emptied and
the emptyqueue can not get filled anymore so no more BUFERRING message
will be posted and the pipeline is stucked in PAUSED for the eternity.
Making sure that we do not try to "buffer" if one of the single queue
does not need buffering, prevents this situtation from happening though it lets the
oportunity for buffering in all other cases.
That implements a new logic where we need all singlequeue to need
buffering for the multiqueue to actually state buffering is needed,
taking the maximum buffering of the single queue as the reference point.
https://bugzilla.gnome.org/show_bug.cgi?id=734412
After EOS there will be no further buffer which could propagate the
error upstream, so nothing is going to post an error message and
the pipeline just idles around.
When eos events are forwarded simultaneouly from two sinkpads on
funnel, it doesnot forward the eos to sourcepad. The reason is
sticky events are stored after the event callbacks are returned.
Therefore while one is about to store the sticky events on the its
sinkpad, other sinkpad starts checking for the eos events on all other
sinkpads and assumes eos is not present yet.
https://bugzilla.gnome.org/show_bug.cgi?id=732851
Avoid relocations and refactor so that we don't calculate
the fixed and known at compile time maximum string size
every time. Also skip the mini object flags which we are
not going to print anyway.
The initial buffers (that were used for timestamping) might have PTS
and DTS set. In order to forward those properly, get the initial
PTS/DTS from the adapter and set them on the reconstructed output
buffer.
https://bugzilla.gnome.org/show_bug.cgi?id=733291
We always work in passthrough mode so there's no point in doing
something more clever in basetransform. Also the basetransform
code leads to problems with incomplete caps and downstream
elements that use GST_PAD_FLAG_ACCEPT_INTERSECT.
https://bugzilla.gnome.org/show_bug.cgi?id=732559
When no data is coming from sinkpads and eos events
arrived at one of the sinkpad, funnel forwards the EOS
event to downstream. It forwards the EOS because lastsink pad
is NULL. Also the unit testcase of the funnel is not checking
the correct behavior as it should. The unit test case should
fail if one of the sink pad has already EOS present on it and
we are trying to push one more EOS.
https://bugzilla.gnome.org/show_bug.cgi?id=731716
The start and stop should represent the currently downloading region.
The estimated-total should represent the remaining time to download
the currently downloading region. This makes it a lot more useful
for applications because they can then use those values to update
the fill region and use the estimated time to delay playback.
Update the docs with this clarification.
When the first segment has position != 0 and position > max-size-time
it will immediatelly cause the multiqueue to signal overrun.
This can happen easily with adaptive streams when switching bitrates
and starting a new group. The segment for this new group will have
a position that is much greater than 0 and will lead to this issue.
This is particularly harmful when the adaptive stream uses mpegts
that doesn't emit no-more-pads and it might happen that only one
of the stream pads was added when the multiqueue overruns and gets
the group ready for exposing. So the user will only get audio or
video.
The solution is to fallback to the sink segment while the source pad
has no segment.
https://bugzilla.gnome.org/show_bug.cgi?id=729124
They are very confusing for people, and more often than not
also just not very accurate. Seeing 'last reviewed: 2005' in
your docs is not very confidence-inspiring. Let's just remove
those comments.
The qlock is released between popping a buffer from the queue
and pushing it. When this buffer causes the sink to wait in
preroll, this lets a query see that the queue is empty, and
push the query then wait for it to be serviced. However, this
will not be done till after peroll, and this will thus block.
If upstream was waiting on buffering to reach 100% before
switching to PLAYING, a deadlock would ensue.
This had been fixed recently by failing queries when the
queue2 was buffering, but this happens to break some other
case (playbin on a local http server and matroska), while
this patch works for both.
See https://bugzilla.gnome.org/show_bug.cgi?id=728345
This should never happen theoretically, but since a transient
failure would get us to silently read wrong data, it's worth
erroring out. And it silence this:
Coverity 206034
The qlock is released between popping a buffer from the queue
and pushing it. When this buffer causes the sink to wait in
preroll, this lets a query see that the queue is empty, and
push the query then wait for it to be serviced. However, this
will not be done till after peroll, and this will thus block.
If upstream was waiting on buffering to reach 100% before
switching to PLAYING, a deadlock would ensue.
We fix it by refusing the query when buffering, as per Wim's
recommendation on IRC.
Use the pad as object for logging to get more context. Use
gst_pad_store_sticky_event() instead of sending the event. This avoids a warning
as here the pad is not yet linked and we actually don't want to send anyway.
Use the last result as a default when pushing a item from a single queue,
otherwise the status gets reset to _OK when pushing events.
This causes problems when mistakenly activating a not-linked stream
that is being ignored upstream as it is not being used (adaptive
scenarios), it will make the multiqueue post a buffering message
on a pad that won't receive buffers
https://bugzilla.gnome.org/show_bug.cgi?id=725917
Make a method to get the seeking threshold. If data is further away from
this threshold we want to perform a seek upstream.
When the current downloaded range can merge with the next range,
actually include the data of the next range into the current range
instead of discarding it. Also decide if we seek to the write position
of the merged range or continue reading.
If the segment event is allowed to be pushed to all pads it
will lead to an assertion of 'sticky event misordering:
segment received before caps' in case the pad-negotiation-mode
is set to 'active' or 'none'.
This patch fixes this by making all sticky events follow the
property like the caps event to prevent misordering warnings.
When a new pad is activated the current sticky events on the
sinkpad are forwarded to it in the proper order.
https://bugzilla.gnome.org/show_bug.cgi?id=723266
When the single queue size was just bumped by 1 to allow more buffers to
be added, the buffers limit could be reduced to the current level when
setting the max-size-buffers property. This would result in a stall
since the queue would not grow anymore at this point.
Prevent this by not reducing a single queue size below the current
number of buffers + 1.
https://bugzilla.gnome.org/show_bug.cgi?id=712597
In the case where one singlequeue is full and all other are not linked, the
growing of the full queue does not work correctly. The result depends on if
the full queue is last in the queue list or not.
https://bugzilla.gnome.org/show_bug.cgi?id=722891
It is already stored inside the GstSegment struct and
was only duplicating information. Also removed some
weird positon if/else that would possibly change the
segment that was going to be pushed downstream
When prerolling/buffering, multiqueue has its buffers limit set
to 0, this means it can take an infinite amount of buffers.
When prerolling/buffering finishes, its limit is set back to 5, but
only if the current level is lower than 5. It should (almost) never be
and this will cause prerolling/buffering to need to wait to reach the
hard bytes and time limits, which are much higher.
This can lead to a very long startup time. This patch fixes this
by setting the single queues to the max(current, new_value) instead
of simply ignoring the new value and letting it as infinite(0)
https://bugzilla.gnome.org/show_bug.cgi?id=712597
The offset can be -1 when we are configured in TIME format. Instead of
failing the seek and erroring, do what and offset of -1 is supposed to
do and simply read from the current offset.
It was used for pad-alloc in 0.10 but currently is completely unused
and not necessary. All pad access is protected by the tee object lock
and keeping another reference to the current pad.
This makes buffering stop in case a stream switch happens. This is
important for adaptive streams that can disable not-linked streams
to avoid consuming the network bandwidth.
https://bugzilla.gnome.org/show_bug.cgi?id=719575
After patch bda406c4, the state of the singlequeue was set to OK, but nothing
would then wake up the thread, as the other wakeup functions only look at
singlequeues that are marked as having received as not-linked.
https://bugzilla.gnome.org/show_bug.cgi?id=708200
* add many missing declarations to sections
* GstController has been removed, update docs
* skip GstIndex when generating documentation
* rephrase so gtkdoc doesn't imagine return value
* add missing argument description for gst_context_new()
* document GstOutputSelectorPadNegotiationMode and move to header-file
https://bugzilla.gnome.org/show_bug.cgi?id=719614
Use gap events to advance the selector's pad position.
This is relevant to keep sync_streams mode working when one of the
streams doesn't have data all the time.
Since the refactoring of GstContext (commits
qc9fa2771b508e9aaeecc700e66e958190476f,
a7f5dc8b8a,
690326f906dc82e41ea58b81cdb2e3e88b754,
d367dc1b0d4ecb37f4d27267e03d7bf0c6c06a6, and
82d158aed3f2e8545e1e7d35085085ff58f18) I am no longer able to get
a shared context for an element that is used twice in a pipeline.
I used the documentation and eglglessink as my reference for
implementing the GstContext logic.
As the code was tied to a hardware decoder, I have ported the
GstContext code to fakesink to show the problem. Using the old
API a single ExampleMgr instance is created, but using the new
API each element is creating its own instance.
In some cases the wait for more data was happening without updating
the buffering state, meaning the API user would not be able to notice
it should pause the pipeline and update UI to indicate that is the
case, the video would likely stutter instead.
https://bugzilla.gnome.org/show_bug.cgi?id=707648
If the multiqueue has automatically grown chances are good that
we will cause the pipeline to starve if the maximum level is reduced
below that automatically grown size.
https://bugzilla.gnome.org/show_bug.cgi?id=707156
When a buffering query is handled it uses the get_buffering_percent()
function to get some statitics. Unfortunately this function also
calculates whether the queue should be buffering and adapts the
global queue2 state in case of state transitions from/to buffering
(including whether a buffering message was posted on the bus!).
This means that there is a race which can cause buffering messages
to never posted if the global state changes happen as a result of aa
query instead of resulting from bytes flowing in/out.
Spotted by Sjoerd Simons.
Change to only query state in get_buffering_percent() and update
state only in update_buffering().
https://bugzilla.gnome.org/show_bug.cgi?id=705332
When in download buffering mode queue2 didn't check if a range offset is
in a undownloaded range before the currently in-progress range. Causing
seeks to an earlier offset to, well, take a while.
When asked about the scheduling flags first check with upstream and
simply add the _SEEKABLE flag when using a temporary file as storage.
This enables the forwarding of _SEQUENTIAL and _BANDWIDTH_LIMITED from
sources if needed.
https://bugzilla.gnome.org/show_bug.cgi?id=704927
A new active pad might not be notified in some cases, which results
in the current track number not being set in playbin.
The active-pad notification is only sent in the chain and sink_event
functions, and only when the buffer or event that triggered the active
pad selection is from the newly activated pad. So in the other case
the notification will never be sent.
https://bugzilla.gnome.org/show_bug.cgi?id=704691
We must be certain that we don't cause a deadlock when blocking the serialized
queries. One such deadlock can happen when we are buffering and downstream is
blocked in preroll and a serialized query arrives. Downstream will not unblock
(and allow our query to execute) until we complete buffering and buffering will
not complete until we can answer the query..
https://bugzilla.gnome.org/show_bug.cgi?id=702840
Otherwise we might get deadlocks caused by lock order inversion:
During the chain function the stream lock is first locked and then the
inputselector lock. During pad release we first locked the inputselector
lock and then deactivating the pad would lock the stream lock.
There's no reason why the inputselector lock should be required while
deactivating and removing the pad, it's only needed before.
https://bugzilla.gnome.org/show_bug.cgi?id=704002
We must be certain that we don't cause a deadlock when blocking the serialized
queries. One such deadlock can happen when we are buffering and downstream is
blocked in preroll and a serialized query arrives. Downstream will not unblock
(and allow our query to execute) until we complete buffering and buffering will
not complete until we can answer the query..
Fixes https://bugzilla.gnome.org/show_bug.cgi?id=702840
During FLUSH_START the query needs to be unblocked already, otherwise
it can lead to deadlocks if the FLUSH_START is the result of something
done from the streaming thread of the srcpad (the queue will never be
emptied!).
Fixes some deadlocks during flushing.
And store queue items differently to not accidentially read
already unreffed queries when flushing. Queries are owned by
upstream and not us.
