FFmpeg is retarded enough not to give us any indication whether it is
(unless we query fields not in the ABI/API). I bet FFmpeg developers
love it when library users have to litter their code with duplicated
information.
Quitting is slightly asynchronous, so the status line can be updated
again. Normally, that's fine, but if quitting comes with a message (such
as with quit_watch_later), it will print the status line again after the
message, which looks annoying. So flush and clear the status message if
it's updated during quitting.
If anyone happened to build with GL disabled, this could lead to option
changes not always refreshing the screen. Since vo_gpu is always enabled
now (just not necessarily any backend for it), we can drop the #if
completely.
(The way this works is a bit idiotic - the option cache exists only to
grab the change notification, which will trigger a redraw and make
vo_gpu update its own second copy of them. But at least it avoids some
layering issues for now.)
Avoids 100% CPU usage due to terminal code retrying read(). Seems like
this was "forgotten" (or there was somehow the assumption poll() would
not signal POLLIN anymore).
Fixes#5842.
This is working towards a change intended in the future: nothing should
write to the option struct directly, but use functions that raise proper
notifications. Until this is complete it will take a while, and this
commit does not change all cases of direct access, just some simple
ones.
In all of these 3 changes, the actual write access is done by the
generic property-option bridge.
C11 can access atomic variables normally (in which case they use the
strictest memory access semantics). But the mpv stdatomic wrapper for
C99 compilers does not allow it, because it couldn't give any
guarantees. This means we always need to access them with atomic macros.
While we're at, use relaxed semantics for the m_config_cache field,
since because it's accessed from a single thread only (essentially
used in a non-atomic way). Switch the comparison arguments to make the
formatting look slightly less weird.
Although the new code actually fires update notifications only when
needed, m_config_cache_update() itself returned a rather coarse change
value, which could indicate change even if none of the cached options
were changed. On top of that, some code (like vo_gpu) calls the update
function on every frame, which would reconfigure the renderer even on
unrelated option changes.
This was always a legacy thing. Remove it by applying an orgy of
mp_get_config_group() calls, and sometimes m_config_cache_alloc() or
mp_read_option_raw().
win32 changes untested.
The --hwdec* options are a good fit for the vd_lavc local option
struct. This annoyingly requires manual prefixing of most of these
options with --vd-lavc (could be avoided by using more sub-struct
craziness, but let's not).
The path functions need to access the option that forces non-default
config directories. Just add it as a field to mpv_global - it seems
justified. The accessed options were always enforced as immutable after
init, so there's not much of a change.
Passing NULL to mp_get_config_group() returns the main option struct.
This is just a dumb hack to deal with inconsistencies caused by legacy
things (as I'll claim), and will probably be changed in the future. So
before littering the whole code base with hard to find NULL parameters,
require using callers an easy to find separate define.
Options with dynamic memory allocations (such as strings) require some
care. They need to be fully copied on initialization, and if a static
default value was declared, we must not free that value either.
Instead of going through the entire thing even for simple types like
integers, really run it only for options with dynamic allocations. To
distinguish types which use dynamic allocations, we can use the fact
that they require a free callback (otherwise they would leak). As a
result initialization of simple types becomes chaper, and the init
function does nothing at all if src==dst for a simple type.
(It's funny how mplayer had M_OPT_TYPE_DYNAMIC since 2002, until we
replaced it by the same heuristic as used here in commit 3bb134969e.
It's also funny how the new check was used only for some asserts, and
finally removed in commit 7539928c1c. I guess at this time I felt like
having uniform code was more important than pointless
micro-optimizations.)
The src==NULL case is removed because it can't happen.
C99 still works, but in theory we're using C11 features already, such as
stdatomic.h. gcc/clang let us use it in C99 mode too, but using C11 is
at least more proper.
Actually rewrite most of the option management code. This affects how
options are allocated, and how thread-safe access to them is done.
One thing that is nicer is that creating m_config_cache does not need to
ridiculously recreate and store the entire option list again. Instead,
option metadata and option storage are now separated. m_config contains
the metadata, and m_config_data all or parts of the actual option
values. (m_config_cache simply uses the metadata part of m_config, which
is immutable after creation.)
The mentioned hack was introduced in commit 1a2319f3e4, and is the
global state around g_group_mutex. Although it was "benign" global
state, it's good that it's finally removed.
For some reason shadow_offset is a int16_t variable (to save some space
or something), which means the static part of the entire option list
must be below 32KB. This is fine, but still add a check against
overflows. (Currently it's 3.6KB. This does not include dynamic
allocations like strings.)
Until now, stopping playback aborted the demuxer and I/O layer violently
by signaling mp_cancel (bound to libavformat's AVIOInterruptCB
mechanism). Change it to try closing them gracefully.
The main purpose is to silence those libavformat errors that happen when
you request termination. Most of libavformat barely cares about the
termination mechanism (AVIOInterruptCB), and essentially it's like the
network connection is abruptly severed, or file I/O suddenly returns I/O
errors. There were issues with dumb TLS warnings, parsers complaining
about incomplete data, and some special protocols that require server
communication to gracefully disconnect.
We still want to abort it forcefully if it refuses to terminate on its
own, so a timeout is required. Users can set the timeout to 0, which
should give them the old behavior.
This also removes the old mechanism that treats certain commands (like
"quit") specially, and tries to terminate the demuxers even if the core
is currently frozen. This is for situations where the core synchronized
to the demuxer or stream layer while network is unresponsive. This in
turn can only happen due to the "program" or "cache-size" properties in
the current code (see one of the previous commits). Also, the old
mechanism doesn't fit particularly well with the new one. We wouldn't
want to abort playback immediately on a "quit" command - the new code is
all about giving it a chance to end it gracefully. We'd need some sort
of watchdog thread or something equally complicated to handle this. So
just remove it.
The change in osd.c is to prevent that it clears the status line while
waiting for termination. The normal status line code doesn't output
anything useful at this point, and the code path taken clears it, both
of which is an annoying behavior change, so just let it show the old
one.
Before this, mpctx->playing was often used to determine whether certain
new state could be added to the playback state. In particular this
affected external files (which added tracks and demuxers). The variable
was checked to prevent that they were added before the corresponding
uninit code. We want to make a small part of uninit asynchronous, but
mpctx->playing needs to stay in the place where it is. It can't be used
for this purpose anymore.
Use mpctx->stop_play instead. Make it never have the value 0 outside of
loading/playback. On unloading, it obviously has to be non-0.
Change some other code in playloop.c to use this, because it seems
slightly more correct. But mostly this is preparation for the following
commit.
This will enable the player core to terminate the demuxers in a "nicer"
way without having to block on network. If it just used demux_free(), it
would either have to block on network, or like currently, essentially
kill all I/O forcefully.
The API is slightly awkward, because demuxer lifetime is bound to its
allocation. On the other hand, changing that would also be awkward, and
introduce weird in-between states that would have to be handled in tons
of places.
Currently unused, to be user later.
Alway give each demuxer its own mp_cancel instance. This makes
management of the mp_cancel things much easier. Also, instead of having
add/remove functions for mp_cancel slaves, replace them with a simpler
to use set_parent function. Remove cancel_and_free_demuxer(), which had
mpctx as parameter only to check an assumption. With this commit,
demuxers have their own mp_cancel, so add demux_cancel_and_free() which
makes use of it.
Them being separate is just dumb. Replace them with a single
demux_free() function, and free its stream by default. Not freeing the
stream is only needed in 1 special case (demux_disc.c), use a special
flag to not free the stream in this case.
The player fully restarts playback when the edition or disk title is
changed. Before this, the player tried to reinitialized playback
partially. For example, it did not print a new "Playing: <file>"
message, and did not send playback end to libmpv users (scripts or
applications).
This playback restart code was a bit messy and could have unforeseen
interactions with various state. There have been bugs before. Since it's
a mostly cosmetic thing for an obscure feature, just change it to a full
restart. This works well, though since it may have consequences for
scripts or client API users, mention it in interface-changes.rst.
The properties/commands touched in this commit are all for obscure
special inputs (BD/DVD/DVB/TV), and they all block on the demuxer/stream
layer. For network streams, this blocking is very unwelcome. They will
affect playback and probably introduce pauses and frame drops. The
player can even freeze fully, and the logic that tries to make playback
abortable even if frozen complicates the player.
Since the mentioned accesses are not needed for network streams, but
they will block on network streams even though they're going to fail,
add a flag that coarsely enables/disables these accesses. Essentially it
establishes a whitelist of demuxers/streams which support them.
In theory you could to access BD/DVD images over network (or add such
support, I don't think it's a thing in mpv). In these cases these
controls still can block and could even "freeze" the player completely.
Writing to the "program" and "cache-size" properties still can block
even for network streams. Just don't use them if you don't want freezes.
Don't allow it to freeze everything when loading a playlist from network
(although you definitely shouldn't do that, but whatever).
This also affects the really obscure --ordered-chapters-files option.
The --playlist option on the other hand has no choice but to freeze the
shit, because there's no concept of aborting the player during command
line parsing.
Until now, they could be aborted only by ending playback, and calling
mpv_abort_async_command didn't do anything.
This requires furthering the mess how playback abort is done. The main
reason why mp_cancel exists at all is to avoid that a "frozen" demuxer
(blocked on network I/O or whatever) cannot freeze the core. The core
should always get its way. Previously, there was a single mp_cancel
handle, that could be signaled, and all demuxers would unfreeze. With
external files, we might want to abort loading of a certain external
file, which automatically means they need a separate mp_cancel. So give
every demuxer its own mp_cancel, and "slave" it to whatever parent
mp_cancel handles aborting.
Since the mpv demuxer API conflates creating the demuxer and reading the
file headers, mp_cancel strictly need to be created before the demuxer
is created (or we couldn't abort loading). Although we give every
demuxer its own mp_cancel (as "enforced" by cancel_and_free_demuxer),
it's still rather messy to create/destroy it along with the demuxer.
