This is the more correct fix for #5447, as regardless of which process
in the job (be it the first or the last) finished first, once we have
waited on a process without ~WNOHANG we don't do that for any subsequent
processes in the job.
It is also a waste to call into the kernel to wait for a process we
already know is completed!
@ridiculousfish had introduced this in 3a45cad12e
to work around an issue with Coverity Scan where it couldn't tell the
mutex was correctly locked, but even with the `fish_mutex_t` hack, it
still emits the same warnings, so there's no pointing in keeping it.
This is necessary for the history race condition test to succeed.
(That test is permanently disabled under WSL (as it always fails) so I
didn't catch this on my end.)
Use `pthread_atfork()` to mark child processes as dirty when `fork()` is
invoked rather than needing to call into the kernel each time
`ASSERT_IS_NOT_FORKED_CHILD()` is called.
This makes simple test cases that hit `ASSERT_IS_NOT_FORKED_CHILD()` 1.8x faster.
------------------------
With a7998c4829 reverted but before this optimization:
```
mqudsi@ZBOOK ~/r/fish-shell> hyperfine -S build/fish 'for i in (seq 100000); test 1 = 1; end'
Benchmark #1: for i in (seq 100000); test 1 = 1; end
Time (mean ± σ): 717.8 ms ± 14.9 ms [User: 503.4 ms, System: 216.2 ms]
Range (min … max): 692.3 ms … 740.2 ms
```
With a7998c4829 reverted and with this optimization:
```
mqudsi@ZBOOK ~/r/fish-shell> hyperfine -S build/fish 'for i in (seq 100000); test 1 = 1; end'
Benchmark #1: for i in (seq 100000); test 1 = 1; end
Time (mean ± σ): 397.2 ms ± 22.3 ms [User: 322.1 ms, System: 79.3 ms]
Range (min … max): 376.0 ms … 444.0 ms
```
Without a7998c4829 reverted and with this optimization:
mqudsi@ZBOOK ~/r/fish-shell> hyperfine -S build/fish 'for i in (seq 100000); test 1 = 1; end'
Benchmark #1: for i in (seq 100000); test 1 = 1; end
Time (mean ± σ): 423.4 ms ± 51.6 ms [User: 363.2 ms, System: 61.3 ms]
Range (min … max): 378.4 ms … 541.1 ms
```
By using a user-land thread-local integer and lock-free (at least under
x86/x64) atomics, we can implement a safe `assert_is_main_thread()`
without calling into the kernel. Thread-local variables are part of
C++11.
This is called a lot in some performance-sensitive areas, so it is worth
optimizing.
This fixes#5438 by having fish block while waiting on a foreground job
via its individual processes by enumerating the procs in reverse order,
such that we hang waiting for the last job in the IO chain to terminate,
rather than the first.
If it's a foreground job, it is related to the currently running exec.
This fixes exec in functions, i.e.
function reload
exec fish
end
would previously always ask about the "function reload" job.
Fixes#5449.
Fixesoh-my-fish/oh-my-fish#664.
Mainly this removes the "TYPE_MASK" macro that just masks off the
higher bits, which I don't think were ever actually used.
Much of this seems like anticipation of future direction, but we're
going somewhere else.
This removes the need to run c-compilation on one file, and allows us
to in future c++-ify this a bit.
There's a lot of bit-fiddling here that is quite unnecessary, better
error-handling would be nice...
So far this removes a few more unused things (because I would have had
to port them), including:
- Functions with ARITY > 3 (even 3 isn't used, but just so we don't
get complacent)
- Variables
- Most functions moved out of the header, because only te_interp is used.
- The te_print function
The function `add_disowned_pgid` adds process *group* ids and not
process ids. It multiplies the value by negative 1 to indicate a wait
on a process group, so the original value must be positive.
If a job is disowned that, for some reason, has a pgid that is special
to waitpid, like 0 (process with pgid of the calling process), -1 (any
process), or our actual pgid, that would lead to us waiting for too
many processes when we later try to reap the disowned processes (to
stop zombies from appearing).
And that means we'd snag away the processes we actually do want to
wait for, which would end with us in a waiting loop.
This is tough to reproduce, the easiest I've found was
fish -ic 'sleep 5 &; disown; set -g __fish_git_prompt_showupstream auto; __fish_git_prompt'
in a git repo.
What we do is to not allow special pgids in the disowned_pids list.
That means we might leave a zombie around (though we probably wait on
0 somewhere), but that's preferable to infinitely looping.
See #5426.
* Severely extended the sorin theme
This theme should now mostly match the original.
* Removed superfluous whitespace
* Inlined external links as ASCII art
* Made myself the author of the sorin theme
* Removed superfluous read delemiter
* Renamed __fish_git_action to fish_print_git_action
* Adde a minor comment
