When this happens, network calls are forcibly aborted (more or less),
but demuxers might keep going, as most of them do not check for forced
exits properly. This can possibly lead to broken packets being added.
Also do not attempt to read more packets in this situation.
Also do not print a stream open failed message if opening was aborted
anyway.
Naturally, there's more than one fourcc that indicates an mjpeg
stream.
I have a particular ancient webcam here (Logitech QuickCam Messanger)
that only supports the single 'JPEG' format, but there are other
devices out there which support both 'JPEG' and 'MJPG' with no visible
differences, and others where the streams are slightly different.
Regardless of those details, it remains correct to treat 'JPEG'
the same as 'MJPG' from a stream consumption perspective.
Do this because retrying reading on higher levels (like the demuxer)
usually causes tons of problems. A hack like this is simpler and could
allow to remove some of the higher level retry behavior.
This works by trying to detect whether the file is appended. If we reach
EOF, check if the file size changed compared to the initial value. If it
did, it means the file was appended at least once, and we set the
p->appending flag. If that flag is set, we simply retry reading more
data every time we encounter EOF. The only way to do this is polling,
and we poll for at most 10 times, after waiting for 200ms every time.
The use of the FFmpeg hls protocol (as opposed to demuxer) is
"discouraged", and probably only causes additional potential security
problems at best, so drop it.
This commit eliminates the following clang warning:
warning: macro expansion producing 'defined' has undefined behavior [-Wexpansion-to-defined]
Going by the clang commit message, this seems to be explicitly specified
as UB by the standard, and they added this warning because MSVC
apparently results in different behavior. Whatever, we can just avoid
the warning with some small changes.
For quite some time, msg.c hasn't output partial log messages anymore,
and instead buffered them in memory. This means the MP_INFO() statement
here just kept appending the message to memory, instead of outputting
it.
Easy enough to fix by abusing the status line (which means the frontend
and this code will "fight" for the status line, but this code seems to
win usually, as the frontend doesn't update it so often).
Users should probably really switch to --cache-pause-initial.
Fixes#5360.
Remove our own hacky reconnection code, and use libavformat's feature for
that. It's disabled by default, and until recently it did not work too
well. This has been fixed in recent ffmpeg git master[1], so there's no reason
to keep our own code.
[1] FFmpeg/FFmpeg@8a108bdea0
We set "reconnect_delay_max" to 7, which limits the maximum time it
waits. Since libavformat doubles the wait time on each reconnect attempt
(starting with 1), and stops trying to reconnect once the wait time is
over the reconnect_delay_max value, this allows for 4 reconnection
attempts which should add to 11 seconds maximum wait time. The default
is 120, which seems too high for normal playback use.
(The user can still override these parameters with --stream-lavf-o.)
Don't drop the stream buffers, because the read call (that must have
been failing) might try to extend an existing read buffer in the first
place. Just move the messy seek logic to stream_lavf.c. (In theory,
stream_lavf should probably make libavformat connect at the correct
offset instead of using a seek to reconnect it again. This patch doesn't
fix it, but at least it's a good argument to have the messing with the
position not in the generic code.)
Also update the comment about avio not supporting reconnecting. It has
that feature now. Maybe we should use it, but only after it gets fixed.
In commit 1199c1e3, we added checks to every libarchive API call to make
sure the archive was closed on ARCHIVE_FATAL - otherwise, libarchive
could endow us with free CVEs (such as it apparently happens when you
continue reading a rar archive that uses features not yet supported by
libarchive).
This broke the fallback for seeking in unseekable archive formats. Of
course libarchive won't tell us directly whether a format implementation
has seek support or not - and OF COURSE it returns ARCHIVE_FATAL if it
has no seek support. (The error string, which you can retrieve via API,
is actually more detailed, and also claims it's an "internal error". I
don't think so, libarchive.) Returning ARCHIVE_FATAL means we have to
assume free CVEs are ahead, and we have to close the archive. Which
breaks the fallback in a dumb way (we have no way of telling which of
those cases happened anyway).
Fix this by assuming that all seek errors are potentially due to lack of
seek support. If the seek call fails, reopen the archive, and set a flag
so the seek API is never tried again. (This means we can still skip
ahead for forward seeks, which is more efficient than skipping from the
start of the archive entry.)
Also fix an old typo in an error message.
Reduce it from 75MB in both directions (forward/backwards) to 10MB each.
The stream cache is kind of becoming useless in favor of the demuxer
cache. Using both doesn't make much sense, because they will contain
duplicated data for no reason.
Still leave it at 10MB, which may help with mp4 a bit. libavformat's mp4
demuxer tends to seek too much, so we try to avoid triggering network
level seeks by having some caching in the stream layer.
I've decided that MP_TRACE means “noisy spam per frame”, whereas
MP_DBG just means “more verbose debugging messages than MSGL_V”.
Basically, MSGL_DBG shouldn't create spam per frame like it currently
does, and MSGL_V should make sense to the end-user and provide mostly
additional informational output.
MP_DBG is basically what I want to make the new default for --log-file,
so the cut-off point for MP_DBG is if we probably want to know if for
debugging purposes but the user most likely doesn't care about on the
terminal.
Also, the debug callbacks for libass and ffmpeg got bumped in their
verbosity levels slightly, because being external components they're a
bit less relevant to mpv debugging, and a bit too over-eager in what
they consider to be relevant information.
I exclusively used the "try it on my machine and remove messages from
MSGL_* until it does what I want it to" approach of refactoring, so
YMMV.
Fix that libarchive fails to return filenames for UTF-8/UTF-16 entries.
The reason is that it uses locales and all that garbage, and mpv does
not set a locale.
Both C locales and wchar_t are shitfucked retarded legacy braindeath. If
the C/POSIX standard committee had actually competent members, these
would have been deprecated or removed long ago. (I mean, they managed to
remove gets().) To justify this emotional outbreak potentially insulting
to unknown persons, I will write a lot of text. Those not comfortable
with toxic language should pretend this is a religious text.
C locales are supposed to be a way to support certain languages and
cultures easier. One example are character codepages. Back when UTF-8
was not invented yet, there were only 255 possible characters, which is
not enough for anything but English and some european languages. So they
decided to make the meaning of a character dependent on the current
codepage. The locale (LC_CTYPE specifically) determines what character
encoding is currently used.
Of course nowadays, this is legacy nonsense. Everything uses UTF-8 for
"char", and what doesn't is broken and terrible anyway. But the old ways
stayed with us, and the stupidity of it as well.
C locales were utterly moronic even when they were invented. The locale
(via setlocale()) is global state, and global state is not a reasonable
way to do anything. It will break libraries, or well modularized code.
(The latter would be forced to strictly guard all entrypoints set
set/restore locales, assuming a single threaded world.)
On top of that, setting a locale randomly changes the semantics of a
bunch of standard functions. If a function respects locale, you suddenly
can't rely on it to behave the same on all systems. Some behavior can
come as a surprise, and of course it will be dependent on the region of
the user (it doesn't help that most software is US-centric, and the US
locale is almost like the C locale, i.e. almost what you expect).
Idiotically, locales were not just used to define the current character
encoding, but the concept was used for a whole lot of things, like e. g.
whether numbers should use "," or "." as decimal separaror. The latter
issue is actually much worse, because it breaks basic string conversion
or parsing of numbers for the purpose of interacting with file formats
and such.
Much can be said about how retarded locales are, even beyond what I just
wrote, or will wrote below. They are so hilariously misdesigned and
insufficient, I can't even fathom how this shit was _standardized_. (In
any case, that meant everyone was forced to implement it.) Many C
functions can't even do it correctly. For example, the character set
encoding can be a multibyte encoding (not just UTF-8, but awful garbage
like Shift JIS (sometimes called SHIT JIZZ), yet functions like
toupper() can return only 1 byte. Or just take the fact that the locale
API tries to define standard paper sizes (LC_PAPER) or telephone number
formatting (LC_TELEPHONE). Who the fuck uses this, or would ever use
this?
But the badness doesn't stop here. At some point, they invented threads.
And they put absolutely no thought into how threads should interact with
locales. So they kept locales as global state. Because obviously, you
want to be able to change the semantics of basic string processing
functions _while_ they're running, right? (Any thread can call
setlocale() at any time, and it's supposed to change the locale of all
other threads.)
At this point, how the fuck are you supposed to do anything correctly?
You can't even temporarily switch the locale with setlocale(), because
it would asynchronously fuckup the other threads. All you can do is to
enforce a convention not to set anything but the C local (this is what
mpv does), or to duplicate standard functions using code that doesn't
query locale (this is what e.g. libass does, a close dependency of mpv).
Imagine they had done this for certain other things. Like errno, with
all the brokenness of the locale API. This simply wouldn't have worked,
shit would just have been too broken. So they didn't. But locales give a
delicious sweet spot of brokenness, where things are broken enough to
cause neverending pain, but not broken enough that enough effort would
have spent to fix it completely.
On that note, standard C11 actually can't stringify an error value. It
does define strerror(), but it's not thread safe, even though C11
supports threads. The idiots could just have defined it to be thread
safe. Even if your libc is horrible enough that it can't return string
literals, it could just just some thread local buffer. Because C11 does
define thread local variables. But hey, why care about details, if you
can just create a shitty standard?
(POSIX defines strerror_r(), which "solves" this problem, while still
not making strerror() thread safe.)
Anyway, back to threads. The interaction of locales and threads makes no
sense. Why would you make locales process global? Who even wanted it to
work this way? Who decided that it should keep working this way, despite
being so broken (and certainly causing implementation difficulties in
libc)? Was it just a fucked up psychopath?
Several decades later, the moronic standard committees noticed that this
was (still is) kind of a bad situation. Instead of fixing the situation,
they added more garbage on top of it. (Probably for the sake of
"compatibility"). Now there is a set of new functions, which allow you
to override the locale for the current thread. This means you can
temporarily override and restore the local on all entrypoints of your
code (like you could with setlocale(), before threads were invented).
And of course not all operating systems or libcs implement this. For
example, I'm pretty sure Microsoft doesn't. (Microsoft got to fuck it up
as usual, and only provides _configthreadlocale(). This is shitfucked on
its own, because it's GLOBAL STATE to configure that GLOBAL STATE should
not be GLOBAL STATE, i.e. completely broken garbage, because it requires
agreement over all modules/libraries what behavior should be used. I
mean, sure, makign setlocale() affect only the current thread would have
been the reasonable behavior. Making this behavior configurable isn't,
because you can't rely on what behavior is active.)
POSIX showed some minor decency by at least introducing some variations
of standard functions, which have a locale argument (e.g. toupper_l()).
You just pass the locale which you want to be used, and don't have to do
the set locale/call function/restore locale nonense. But OF COURSE they
fucked this up too. In no less than 2 ways:
- There is no statically available handle for the C locale, so you have
to initialize and store it somewhere, which makes it harder to make
utility functions safe, that call locale-affected standard functions
and expect C semantics. The easy solution, using pthread_once() and a
global variable with the created locale, will not be easily accepted
by pedantic assholes, because they'll worry about allocation failure,
or leaking the locale when using this in library code (and then
unloading the library). Or you could have complicated library
init/uninit functions, which bring a big load of their own mess.
Same for automagic DLL constructors/destructors.
- Not all functions have a variant that takes a locale argument, and
they missed even some important ones, like snprintf() or strtod() WHAT
THE FUCK WHAT THE FUCK WHAT THE FUCK WHAT THE FUCK WHAT THE FUCK WHAT
THE FUCK WHAT THE FUCK WHAT THE FUCK WHAT THE FUCK
I would like to know why it took so long to standardize a half-assed
solution, that, apart from being conceptually half-assed, is even
incomplete and insufficient. The obvious way to fix this would have
been:
- deprecate the entire locale API and their use, and make it a NOP
- make UTF-8 the standard character type
- make the C locale behavior the default
- add new APIs that explicitly take locale objects
- provide an emulation layer, that can be used to transparently build
legacy code without breaking them
But this wouldn't have been "compatible", and the apparently incompetent
standard committees would have never accepted this. As if anyone
actually used this legacy garbage, except other legacy garbage. Oh yeah,
and let's care a lot about legacy compatibility, and let's not care at
all about modern code that either has to suffer from this, or subtly
breaks when the wrong locales are active.
Last but not least, the UTF-8 locale name is apparently not even
standardized. At the moment I'm trying to use "C.UTF-8", which is
apparently glibc _and_ Debian specific. Got to use every opportunity to
make correct usage of UTF-8 harder. What luck that this commit is only
for some optional relatively obscure mpv feature.
Why is the C locale not UTF-8? Why did POSIX not standardize an UTF-8
locale? Well, according to something I heard a few years ago, they're
considering disallowing UTF-8 as locale, because UTF-8 would violate
certain ivnariants expected by C or POSIX. (But I'm not sure if I
remember this correctly - probably better not to rage about it.)
Now, on to libarchive.
libarchive intentionally uses the locale API and all the broken crap
around it to "convert" UTF-8 or UTF-16 (as contained in reasonably sane
archive formats) to "char*". This is a good start!
Since glibc does not think that the C locale uses UTF-8, this fails for
mpv. So trying to use archive_entry_pathname() to get the archive entry
name fails if the name contains non-ASCII characters.
Maybe use archive_entry_pathname_utf8()? Surely that should return
UTF-8, since its name seems to indicate that it returns UTF-8. But of
fucking course it doesn't! libarchive's horribly convoluted code (that
is full of locale API usage and other legacy shit, as well as ifdefs and
OS specific code, including Windows and fucking Cygwin) somehow fucks up
and fails if the locale is not set to UTF-8. I made a PR fixing this in
libarchive almost 2 years ago, but it was ignored.
So, would archive_entry_pathname_w() as fallback work? No, why would it?
Of course this _also_ involves shitfucked code that calls shitfucked
standard functions (or OS specific ifdeffed shitfuck). The truth is that
at least glibc changes the meaning of wchar_t depending on the locale.
Unlike most people think, wchar_t is not standardized to be an UTF
variant (or even unicode) - it's an encoding that uses basic units that
can be larger than 8 bit. It's an implementation defined thing. Windows
defines it to 2 bytes and UTF-16, and glibc defines it to 4 bytes and
UTF-32, but only if an UTF-8 locale is set (apparently).
Yes. Every libarchive function dealing with strings has 3 variants:
plain, _utf8, and _w. And none of these work if the locale is not set.
I cannot fathom why they even have a wchar_t variant, because it's
redundant and fucking useless for any modern code.
Writing a UTF-16 to UTF-8 conversion routine is maybe 3 pages of code,
or a few lines if you use iconv. But libarchive uses all this glorious
bullshit, and ends up with 3 not working API functions, and with over
4000 lines of its own string abstraction code with gratuitous amounts of
ifdefs and OS dependent code that breaks in a fairly common use case.
So what we do is:
- Use the idiotic POSIX 2008 API (uselocale() etc.) (Too bad for users
who try to build this on a system that doesn't have these - hopefully
none are left in 2017. But if there are, torturing them with obscure
build errors is probably justified. Might be bad for Windows though,
which is a very popular platform except on phones.)
- Use the "C.UTF-8" locale, which is probably not 100% standards
compliant, but works on my system, so it's fine.
- Guard every libarchive call with uselocale() + restoring the locale.
- Be lazy and skip some libarchive calls. Look forward to the unlikely
and astonishingly stupid bugs this could produce.
We could also just set a C UTF-8 local in main (since that would have no
known negative effects on the rest of the code), but this won't work for
libmpv.
We assume that uselocale() never fails. In an unexplainable stroke of
luck, POSIX made the semantics of uselocale() nice enough that user code
can fail failures without introducing crash or security bugs, even if
there should be an implementation fucked up enough where it's actually
possible that uselocale() fails even with valid input.
With all this shitty ugliness added, it finally works, without fucking
up other parts of the player. This is still less bad than that time when
libquivi fucked up OpenGL rendering, because calling a libquvi function
would load some proxy abstraction library, which in turn loaded a KDE
plugin (even if KDE was not used), which in turn called setlocale()
because Qt does this, and consequently made the mpv GLSL shader
generation code emit "," instead of "." for numbers, and of course only
for users who had that KDE plugin installed, and lived in a part of the
world where "." is not used as decimal separator.
All in all, I believe this proves that software developers as a whole
and as a culture produce worse results than drug addicted butt fucked
monkeys randomly hacking on typewriters while inhaling the fumes of a
radioactive dumpster fire fueled by chinese platsic toys for children
and Elton John/Justin Bieber crossover CDs for all eternity.
According to
https://github.com/libarchive/libarchive/pull/773#issuecomment-334892291
we're not allowed to "continue reading" (post above) or performing "more
operations" (comments in archive.h header), whatever that means. Assume
closing and freeing the archive is still ok.
Since the codec already includes logic for closing and reopening the
archive for seeking in unseekable archives, this probably isn't too bad.
Untested due to lack of crashing sample (I lost my original test case,
and as recently user-provided one didn't crash).
In the extreme case, reading 1 byte would wake up the cache to make the
cache thread read 1 byte. This would be extremely inefficient. This will
not normally happen in our cache implementation, but it's still present
to some lesser degree. Normally you'd set a predefined "cache too low"
boundary, after which you would restart reading. For some reason
something like this is already present using a hardcoded value
(FILL_LIMIT - I don't even know the deeper reason why this exists). So
use that to reduce wakeups.
This doesn't fix redundant wakeups on EOFs, which is especially visible
should something keep retrying reading on EOF (like in an endless loop).
This should actually cover all of them, if you take into account that
some unchanged GPL source files include header files with such checks.
Also this was done already for the libaf derived code.
This is only for "safety" and to avoid misunderstandings.
ATSC is a mix of terrestrial and cable,
and depending on modulation is actually using
DVBC_ANNEX_B. Thus, we need to override the delivery
system depending on the modulation, channel by channel.
Signed-off-by: Oliver Freyermuth <o.freyermuth@googlemail.com>
These values are kept with a different unit in VDR style config
for all delivery systems, not only for DVB-S / DVB-S2.
Signed-off-by: Oliver Freyermuth <o.freyermuth@googlemail.com>
Dump the complete raw tuning commands to allow for debugging
on low level.
Also, remove code duplication and some variable shadowing.
Signed-off-by: Oliver Freyermuth <o.freyermuth@googlemail.com>
Also, in case tuning fails with timeout even though the ioctl
was accepted by the device, fall back to DVBv3 tuning.
This may go wrong for multi-delivery-system cards,
so issue an error message in that case.
Signed-off-by: Oliver Freyermuth <o.freyermuth@googlemail.com>
iive agreed to relicense things that are still in mpv to LGPLv2.1. So
change the licenses of the affected files, and rename the configure
switch for LGPL mode to --enable-preliminary-lgpl2.
(The "preliminary" part will probably be removed from the configure
switch soon as well.)
Also player/main.c hasn't had GPL parts since a few commits ago.
This affects small seeks backwards while within the buffer. Demuxers
usually avoid this, so it's probably not triggered very often. (Although
demux_mkv.c potentially triggers it often, and it uses stream_peek() to
explicitly guarantee that it can use this code to seek back.) The
condition is complex enough to warrant an assertion.
Parsing the texture data as raw strings makes the textures the most
portable and self-contained. In order to facilitate different types of
shaders, the parse_user_shader interaction has been changed to instead
have it loop through blocks and call the passed functions for each valid
block parsed. This is more modular and also cleaner, with better code
separation.
Closes#4586.
While this is perfectly OK on Unix, it causes annoying valgrind
warnings, and might be otherwise confusing to others.
On Windows, the runtime can actually abort the process if this is
called.
push.c part taken from a patch by Pedro Pombeiro.
While I'm not particularly attached to this, the history is pretty
simple, and all relevant authors have agreed.
2f004875: removed in 2c693a47, patch author was not asked.
1ef239a4: removed, author was not asked.
cehoyos, who did not agree to the relicensing, added bcb5c78ce3. If
there was copyright, we consider it gone, because the table changed. It
does not map file extension to a FourCC anymore, and codecs.conf is
gone. The new mapping is a libavcodec codec name (happens to be the same
as the file extension).
The same applies to commits 60ecafec, b749836b, 5b3e3be1. None of these
authors were contacted. These were before the code was replaced with a
table (in d0326807). The parts outside of demux_mf.c were removed a long
time ago. Like in the previous comment, we don't think any copyright
applies at least to the new code (at least after the FourCC removal).
iive authored 0aa37a0d, which is probably still left in some form, and
makes demux_mf.c "LGPL 3 or later".
stream_avdevice.c (unrelated) has been marked as LGPL before.
If they are copyrightable, iive's changes (commits listed in cache.c)
would make them LGPL 3+. To avoid that options.c becoming LGPL 3, move
the option declarations to cache.c. struct mp_cache_opts is still in
options.h, but we consider that irrelevant, and options.h will become
LGPL 2.1+ later.
The user bugmen0t was apparently a shared github account with publicly
available login. Thus, we can't get LGPL relicensing permission from the
people who used this account. To relicense successfully, we have to
remove all their changes.
This commit should remove 20d1fc13, f26fb009, defbe48d. It also should
remove whatever test fragments were copied from the ancient configure,
as well as some configure logic (potentially that device path stuff).
I think this change still preserves the most important use-cases of OSS:
BSDs, and the Linux OSS emulation (the latter for testing only).
According to an OSS user, the 4front checks were probably broken anyway.
The SunAudio stuff was probably for (Open)Solaris, which is dead.
ao_oss.c itself will remain GPL, and still contains bugmen0t changes.
All relevant authors have agreed.
There are two exceptions, patches by authors who could not be reached.
This commit tries to remove their copyright.
a0f08fbe: messes with the seeking code corner cases. The EOF flag logic
was changed at some point, and always had a flaky history (see e.g.
347cf97250274ca370411f275999efb90d5e6084ff08d0c32e2f77e3de5566f09554a844, all which happened after that patch, MPlayer ones without that
patch). I claim that all of the copyright the patch might have added is
gone. Except the message in stream_seek(), which this commit removes.
The other code removed/changed in stream_seek() is probably not from
that patch, but it doesn't hurt to be sure, and also makes it more
readable. (It might change the behavior so that sometimes the eof flag
is set after a seek, but it doesn't matter here.)
2aa6acd9: it looks like the seek_forward() modified by this patch was
later moved to stream.c and renamed to stream_skip_read() in a790f2133.
(Looking closer at it, it was actually modified again a bunch of times,
fixing the logic.) I rewrote it in this commit. The code ended up rather
similar, which probably could lead to doubts whether this was done
properly, but I guess the reader of this will just have to believe me. I
knew what stream_skip_read() was supposed to do (which was reinforced
when I tried to replace it on the caller side), without reading the
pre-existing code in detail. I had to "relearn" the logic how buf_pos
and bug_len work - it was actually easy to see from stream_read_char()
how to skip the data, essentially by generalizing its logic from 1 byte
to N bytes. From the old code I only "used" the fact that it's obviously
a while(len>0) look, that has to call stream_fill_buffer repeatedly to
make progress. At first I actually didn't use stream_fill_buffer_by(),
but the variant without _by, but readded it when I checked why the old
code used it (see cd7ec016e7). This has to be good enough. In the end,
it's hard to argue that this could be implemented in a way not using
such a loop.
Other than this, I could add the usual remarks about how this code was
not modularized in the past, and how stream.c contained DVD code, and
how this was later modularized, moving the copyright to other files, and
so on. Also, if someone wrote a stream module, and was not asked about
LGPL relicensing, we don't consider the entry in stream_list[]
copyrightable.
This file is an leftover from when img_format.h was changed from using
the ancient FourCCs (based on Microsoft multimedia conventions) for
pixel formats to a simple enum. The remaining cases still inherently
used FourCCs for whatever reasons.
Instead of worrying about residual copyrights in this file, just move it
into code we don't want to relicense (the ancient Linux TV code). We
have to fix some other code depending on it. For the most part, we just
replace the MP_FOURCC macro with libavutil's MKTAG (although the macro
definition is exactly the same). In demux_raw, we drop some pre-defined
FourCCs, but it's not like it matters. (Instead of
--demuxer-rawvideo-format use --demuxer-rawvideo-mp-format.)
All authors agreed.
The author of 1ee8ce75 did not respond, but it was a mpv pull request,
and at this time DOCS/contribute.md and the "Copyright" file stated that
all contributions must include LGPL relicensing permission. But you
could claim that this was too "hidden". Sort of a corner case, I guess,
but not my problem.
The original functions come from 24c6f11c8b, which says that these
functions were copied from another project. This other project is GPL
and was written by an unknown author, so there is no hope to relicense
them to LGPL.
Replace the existing functions with code written by Avi Halachmi. He did
not see the old code, but wrote it based on the function signature and
an extended description of what they should do (http://sprunge.us/edia).
Some additional help was provided by me (in particular the function of
the "ok" parameter and how to implement it - not in the original
ASFRecorder code).
Some of the code is hilariously similar, but these are coincidences. The
name of the variable "c" probably "leaked" from me, but "o" is a true
coincidence.
The code was integrated by me - my only change is changing the function
names to the old ones, moving the order of the top-level declarations,
and changing "default_ok" to "url_default_ok", and changing the strings
from char* to char[].
The author of the new code is Avi Halachmi.
Commit 374600cec0 ("cache: propagate seek failures") changed
stream-level seeks to be done in the calling thread so possible errors
could be reported. This commit included some rationale why doing the
stream-level seeks synchronously was not a big issue. However, the
following fixup commit f4d62dc4a0 changed the seek code to always
synchronize with the cache thread and do seek handling there. This is
a problem because it affects even seeks within already cached data
(which require no stream-level seek). With a network server that sends
data in bursts, the cache thread can be blocked in a read call for a
long time; the added synchronization means that seeking within already
downloaded data can have unnecessary long delays.
Change cache_seek() to check whether the seek is expected to result in
a stream-level seek, and skip synchronization if it is not. This means
that seeks within the cached portion of the file now again happen
immediately without possibly waiting for network.
Signed-off-by: wm4 <wm4@nowhere>
