We want to distinguish actual errors, and just aborting the program
intentionally.
Also be a bit more careful with handling the wait() exit status: do not
called WEXITSTATUS() without checking WIFEXITED() first.
This will be used in the following commit, which adds screenshot_raw.
The reasoning is that this will be better for binding scripting
languages.
One could special-case the screenshot_raw commit and define fixed
semantics for passing through a pointer using the current API, like
formatting a pointer as string. But that would be ridiculous and
unclean.
It simply doesn't work, and is hard to make work. Lua 5.3 is a different
language from 5.1 and 5.2, and is different enough to make adding
support a major issue. Most importantly, 5.3 introduced integer types,
which completely mess up any code which deals with numbers.
I tried to make this a compile time check, but failed. Still at least
try to avoid selecting the 5.3 pkg-config package when the generic "lua"
name is used (why can't Lua upstream just provide an official .pc
file...). Maybe this actually covers all cases.
Fixes#1729 (kind of).
It was already accidentally used unconditionally by command.c.
Apparently this worked well for us, so don't change anything about,
but should it be unavailable, fail at configure time instead of compile
time.
When used with mp.get_screen_size(), mp.get_screen_margins() allows a
Lua script to determine what portion of the mpv window actually has the
video in it.
Before this commit, this was defined to trigger undefined behavior. This
was nice because it required less code; but on the other hand, Lua as
well as IPC support had to check these things manually. Do it directly
in the API to avoid code duplication, and to make the API more robust.
(The total code size still grows, though...)
Since all of the failure cases were originally meant to ruin things
forever, there is no way to return error codes. So just print the
errors.
- --lua and --lua-opts change to --script and --script-opts
- 'lua' default script dirs change to 'scripts'
- DOCS updated
- 'lua-settings' dir was _not_ modified
The old lua-based names/dirs still work, but display a warning.
Signed-off-by: wm4 <wm4@nowhere>
The subprocess code was already split into fairly general functions,
separate from the Lua code. It's getting pretty big though, especially
the Windows-specific parts, so move it into its own files.
Normally, when creating a process with inherited handles on Windows, the
process inherits all inheritable handles from the parent, including ones
that were created on other threads. This can cause a race condition,
where unintended handles are copied into the new process, preventing
them from being closed correctly while the process is running. The only
way to prevent this on Windows XP was to serialise the creation of all
inheritable handles, which is clearly unacceptable for libmpv.
Windows Vista solves this problem by allowing programs to specify
exactly which handles are inherited, so do that on Vista and up.
See http://blogs.msdn.com/b/oldnewthing/archive/2011/12/16/10248328.aspx
The CREATE_NO_WINDOW flag is used to prevent the subprocess from
creating an empty console window when mpv is not running in a console.
When mpv is running in a console, it causes the subprocess to detach
itself, and prevents it from seeing Ctrl+C events, so it hangs around in
the background after mpv is killed.
Fix this by only specifying CREATE_NO_WINDOW when mpv is not attached to
a console. When it is attached to a console, subprocesses will
automatically inherit the console and correctly receive Ctrl+C events.
I'm not sure if this is necessary, but it can't hurt, and it's what
you're supposed to do before leaving the stack frame that contains the
OVERLAPPED object and the buffer. If there is no pending I/O, CancelIo
will do nothing and GetOverlappedResult will silently fail.
Instead of threads, use overlapped (asynchronous) I/O to read from both
stdout and stderr. Like in d0643fa, stdout and stderr could be closed at
different times, so a sparse_wait function is added to wrap
WaitForMultipleObjects and skip NULL handles.
Now that the code for stderr and stdout does exactly the same things,
and the specialization is in the callbacks, this is blatantly
duplicated.
Also, define a typedef for those callbacks to reduce the verbosity.
Pretty much a fringe-feature, but also it's awkward if something appears
on the terminal with no indication for the source.
This is made quite awkward by the fact that stderr and stdout could be
closed at different times, and that poll() doesn't accept "holes" in its
FD list. Invalid (.e.g negative) FDs just make it return immediately, as
required by the standard. So sparse_poll() takes care of the messy
details.
What was the purpose of that? Probably none.
Also simplify another thing: if we get the cancel signal through FD,
there's no reason to check it separately.
Because Lua is so terrible, it's easy to confuse temporary values pushed
to the Lua stack with arguments if the arguments are checked after that.
Add a hack that should fix this.
Thanks to the recently introduced mp_lua_PITA(), this is "simple" now.
It fixes leaks on Lua errors. The hack to avoid stack overflows
manually isn't needed anymore, and the Lua error handler will take
care of this.
The JSON parser was introduced for the IPC protocol, but I guess it's
useful here too.
The motivation for this commit is the same as with 8e4fa5fc (again).
Because 1) Lua is terrible, and 2) popen() is terrible. Unfortunately,
since Unix is also terrible, this turned out more complicated than I
hoped. As a consequence and to avoid that this code has to be maintained
forever, add a disclaimer that any function in Lua's utils module can
disappear any time. The complexity seems a bit ridiculous, especially
for a feature so far removed from actual video playback, so if it turns
out that we don't really need this function, it will be dropped again.
The motivation for this commit is the same as with 8e4fa5fc.
Note that there is an "#ifndef __GLIBC__". The GNU people are very
special people and thought it'd be convenient to actually declare
"environ", even though the POSIX people, which are also very special
people, state that no header declares this and that the user has to
declare this manually. Since the GNU people overtook the Unix world with
their very clever "embrace, extend, extinguish" strategy, but not 100%,
and trying to build without _GNU_SOURCE is hopeless; but since there
might be Unix environments which support _GNU_SOURCE features partially,
this means that in practice "environ" will be randomly declared or not
declared by system headers. Also, gcc was written by very clever people
too, and prints a warning if an external variable is declared twice (I
didn't check, but I suppose redeclaring is legal C, and not even the gcc
people are clever enough to only warn against a definitely not legal C
construct, although sometimes they do this), ...and since we at mpv hate
compiler warnings, we seek to silence them all. Adding a configure test
just for a warning seems too radical, so we special-case this against
__GLIBC__, which is hopefully not defined on other libcs, especially not
libcs which don't implement all aspects of _GNU_SOURCE, and redefine
"environ" on systems even if the headers define it already (because they
support _GNU_SOURCE - as I mentioned before, the clever GNU people wrote
software THAT portable that other libcs just gave up and implemented
parts of _GNU_SOURCE, although probably not all), which means that
compiling mpv will print a warning about "environ" being redefined, but
at least this won't happen on my system, so all is fine. However, should
someone complain about this warning, I will force whoever complained
about this warning to read this ENTIRE commit message, and if possible,
will also force them to eat a printed-out copy of the GNU Manifesto, and
if that is not enough, maybe this person could even be forced to
convince the very clever POSIX people of not doing crap like this:
having the user to manually declare somewhat central symbols - but I
doubt it's possible, because the POSIX people are too far gone and only
care about maintaining compatibility with old versions of AIX and HP-UX.
Oh, also, this code contains some subtle and obvious issues, but writing
about this is not fun.
Using the Lua API is a big PITA because it uses longjmp() error
handling. That is, a Lua API function could any time raise an error and
longjmp() to a lower part of the stack. This kind of "exception
handling" is completely foreign to C, and there are no proper ways to
clean up the "skipped" stack frames.
Other than avoiding such situations entirely, the only way to deal with
this is using Lua "userdata", which is basically a malloc'ed data block
managed by the Lua GC, and which can have a destructor function
associated (__gc metamethod).
This requires an awful lot of code (because the Lua API is just so
terrible), so I avoided this utnil now. But it looks like this will make
some of the following commits much easier, so here we go.
mp_stat() instead of stat() was used in the normal code (i.e. even
on Unix), because MinGW-w64 has an unbelievable macro-mess in place,
which prevents solving this elegantly.
Add some dirty workarounds to hide mp_stat() from the normal code
properly. This now requires replacing all functions that use the
struct stat type. This includes fstat, lstat, fstatat, and possibly
others. (mpv currently uses stat and fstat only.)
Merges pull request #1094, with some minor changes. mpv expects IEEE,
and IEEE allows divisions by 0 for floats, so these shouldn't actually
be a problem, but do it anyway for the sake of clang.
Signed-off-by: wm4 <wm4@nowhere>
bstr.c doesn't really deserve its own directory, and compat had just
a few files, most of which may as well be in osdep. There isn't really
any justification for these extra directories, so get rid of them.
The compat/libav.h was empty - just delete it. We changed our approach
to API compatibility, and will likely not need it anymore.
The OSD is marked as changed, but the core isn't notified and this
doesn't immediately wakeup. (Possibly the OSD code should wakeup the
core instead, but maybe that woudl be overkill.)
Observed when using "mp.use_suspend = false" in the OSC, and pausing,
and moving the mouse pointer out of the window. The last part of the
fade remained visible for longer than intended.
