Sometimes people write strange things like "assert(x), something();"
and this will not work if "assert(x)" expands to "".
So make it expand to ((void)0) instead.
- Remove goofy _r suffix from syscall names.
- Don't take a signed buffer size.
- Use Userspace<T>.
- Make TTY::tty_name() return a String instead of a StringView.
This syscall allows a parent process to disown a child process, setting
its parent PID to 0.
Unparented processes are automatically reaped by the kernel upon exit,
and no sys$waitid() is required. This will make it much nicer to do
spawn-and-forget which is common in the GUI environment.
This commit adds an implementation of memmem, using the Bitap text
search algorithm for needles smaller than 32 bytes, and a naive loop
search for longer needles.
"0" was interpreted as a base-8 prefix, and the parse pointer was then
unconditionally advanced, causing us to consume zero characters.
This unbreaks the git port. :^)
(We should really have tests for LibC..)
This being inline somehow broke the binutils autoconf scripts. It used
to work, so I suspect that some other change to LibC has caused those
autoconf scripts to go down a new path.
Regardless, this seems perfectly sensible.
There's no great advantage to using MMX instructions here on modern
processors, since REP MOVSB/STOSB are optimized in microcode anyway
and tend to run much faster than MMX/SSE/AVX variants.
This also makes it much easier to implement high-level emulation of
memcpy/memset in UserspaceEmulator once we get there. :^)
While profiling I noticed that gettid() was hitting gs register
twice, once for the initial fetch of s_cache_tid out of TLS for
the initialization check, and then again when we return the actual
value.
Optimize the implementation to cache the value so we avoid the
double fetch during the 99% case where it's already set. With
this change gettid() goes from being the 3rd most sampled function
in test-js, to pretty much disappearing into ~20th place.
Additionally add the same optimization to getpid().
This works the same as gettid(). No sense in making a syscall to the
kernel every time you ask for the PID since it won't change.
Just like gettid(), the cache is invalidated on fork().
For now, only the non-standard _SC_NPROCESSORS_CONF and
_SC_NPROCESSORS_ONLN are implemented.
Use them to make ninja pick a better default -j value.
While here, make the ninja package script not fail if
no other port has been built yet.
These new syscalls allow you to send and receive file descriptors over
a local domain socket. This will enable various privilege separation
techniques and other good stuff. :^)
ppoll() is similar() to poll(), but it takes its timeout
as timespec instead of as int, and it takes an additional
sigmask parameter.
Change the sys$poll parameters to match ppoll() and implement
poll() in terms of ppoll().
pselect() is similar() to select(), but it takes its timeout
as timespec instead of as timeval, and it takes an additional
sigmask parameter.
Change the sys$select parameters to match pselect() and implement
select() in terms of pselect().
And rewrite the timeval functions as inline functions.
Also add the non-standard but fairly common and useful
TIMEVAL_TO_TIMESPEC / TIMESPEC_TO_TIMEVAL functions.
posix_spawn() tries to present semantics as if no fork() is happening
behind the scenes, so running arbitrary atexit handlers of the parent
in the child seems like the wrong thing to do.
It looks like they're considered a bad idea, so let's not add
them before we need them. I figured it's good to have them in
git history if we ever do need them though, hence the add/remove
dance.
Add seteuid()/setegid() under _POSIX_SAVED_IDS semantics,
which also requires adding suid and sgid to Process, and
changing setuid()/setgid() to honor these semantics.
The exact semantics aren't specified by POSIX and differ
between different Unix implementations. This patch makes
serenity follow FreeBSD. The 2002 USENIX paper
"Setuid Demystified" explains the differences well.
In addition to seteuid() and setegid() this also adds
setreuid()/setregid() and setresuid()/setresgid(), and
the accessors getresuid()/getresgid().
Also reorder uid/euid functions so that they are the
same order everywhere (namely, the order that
geteuid()/getuid() already have).
All the file actions stuff is still missing for now,
as is POSIX_SPAWN_SETSCHEDULER (not sure what that's
supposed to do) and POSIX_SPAWN_RESETIDS.
Implemented in userspace for now. Once there are users,
it'll likely make sense to make this a syscall for
performance reasons.
A simple test program of the form
extern char **environ;
int main(int argc, char* argv[])
{
pid_t pid;
char* args[] = { "ls", NULL };
posix_spawnp(&pid, "ls", nullptr, nullptr, args, environ);
}
works fine.
We were getting a little overly memey in some places, so let's scale
things back to business-casual.
Informal language is fine in comments, commits and debug logs,
but let's keep the runtime nice and presentable. :^)
