|author||wm4 <wm4@nowhere>||2014-10-19 01:42:28 +0200|
|committer||wm4 <wm4@nowhere>||2014-10-19 05:51:37 +0200|
lua: add an utility function for starting processes
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.
Diffstat (limited to 'old-configure')
1 files changed, 1 insertions, 0 deletions
diff --git a/old-configure b/old-configure
index cf2c4c9cde..26fee13711 100755
@@ -989,6 +989,7 @@ cat > $TMPC << EOF
#define HAVE_NANOSLEEP 1
#define HAVE_SDL1 0
#define HAVE_WAIO 0
+#define HAVE_POSIX_SPAWN 1
#define DEFAULT_CDROM_DEVICE "/dev/cdrom"
#define DEFAULT_DVD_DEVICE "/dev/dvd"