Let's hope this doesn't causes build failures for e.g. musl: I just
know it's good on macOS and our Linux CI.
It's been a long time.
One fix this brings, is I discovered we #include assert.h or cassert
in a lot of places. If those ever happen to be in a file that doesn't
include common.h, or we are before common.h gets included, we're
unawaringly working with the system 'assert' macro again, which
may get disabled for debug builds or at least has different
behavior on crash. We undef 'assert' and redefine it in common.h.
Those were all eliminated, except in one catch-22 spot for
maybe.h: it can't include common.h. A fix might be to
make a fish_assert.h that *usually* common.h exports.
This is a big cleanup to how tty transfer works. Recall that when job
control is active, we transfer the tty to jobs via tcsetpgrp().
Previously, transferring was done "as needed" in continue_job. That is, if
we are running a job, and the job wants the terminal and does not have it,
we will transfer the tty at that point.
This got pretty weird when running mixed pipelines. For example:
cmd1 | func1 | cmd2
Here we would run `func1` before calling continue_job. Thus the tty
would be transferred by the nested function invocation, and also restored
by that invocation, potentially racing with tty manipulation from cmd1 or
cmd2.
In the new model, migrate the tty transfer responsibility outside of
continue_job. The caller of continue_job is then responsible for setting up
the tty. There's two places where this gets done:
1. In `exec_job`, where we run a job for the first time.
2. In `builtin_fg` where we continue a stopped job in the foreground.
Fixes#8699
FISH_USE_POSIX_SPAWN is always defined, thanks to the line
#define FISH_USE_POSIX_SPAWN HAVE_SPAWN_H
So replace #ifdef with #if to fix compilation on platforms lacking
spawn.h. Also make the spawn.h inclusion condition consistent across
files.
This changes how fish attempts to protect itself from calling tcsetpgrp() too
aggressively. Recall that tcsetpgrp() will "force" itself, if SIGTTOU is
ignored (which it is in fish when job control is enabled).
Prior to this fix, we avoided SIGTTINs by only transferring the tty ownership
if fish was already the owner. This dated from a time before we had really
nailed down how pgroups should be assigned. Now we more deliberately assign a
job's pgroup so we don't need this conservative check.
However we still need logic to avoid transferring the tty if fish is not the
owner. The bad case is when job control is enabled while fish is running in the
background - here fish would transfer the tty and "steal" from the foreground
process.
So retain the checks of the current tty owner but migrate them to the point of
calling tcsetpgrp() itself.
Prior to this change, the posix_spawn code paths used a fair amount of
manual management around its allocated structures (attrs and file actions).
Encapsulate this into a new class that manages memory management and error
handling.
Prior to this, jobs all had a pgid, and fish has to work hard to ensure
that pgids were inherited properly for nested jobs. But now the job tree
is the source of truth and there is only one location for the pgid.
Soon we will have more complicated logic around whether to call tcsetpgrp.
Prepare to centralize the logic by passing in the new term owner pgrp,
instead of having child_setup_process perform the decision.
25afc9b377 made this unnecessary by
having child processes wait for a signal after fork(), but this change
was later reverted. If we artificially slow down fish (e.g. with a sleep)
after the fork call, we see commands getting backgrounded by mistake.
Put back the tcsetgrp() call.
Now that we use an internal process to perform builtin output, simplify the
logic around how it is performed. In particular we no longer have to be
careful about async-safe functions since we do not fork.
Also fix a bunch of comments that no longer apply.
This switches IO redirections after fork() to use the dup2_list_t,
instead of io_chain_t. This results in simpler code with much simpler
error handling.
This switches IO redirections after fork() to use the dup2_list_t,
instead of io_chain_t. This results in simpler code with much simpler
error handling.
The job control functions were a bit messy, in particular
`set_child_group`'s name would imply that all it does is set the child
group, but in reality it used to set the child group (via `setpgid`),
set the job's pgrp if it hasn't been set, and possibly assign control of
the terminal to the newly-created job.
These have been split into separate functions. Now `set_child_group`
does just (and only) that, `maybe_assign_terminal` might assign the
terminal to the new pgrp, and `on_process_created` is used to set the
job properties the first time an external process is created. This might
also speed things up (but probably not noticeably) as there are no more
repeated calls to `getpgrp()` if JOB_CONTROL is not set.
Additionally, this closes#4715 by no longer unconditionally calling
`setpgid` on all new processes, including those created by `posix_spawn`
which does not need this since the child's pgrep is set at in the
arguments to that API call.
keepalive processes are typically killed by the main shell process.
However if the main shell exits the keepalive may linger. In WSL
keepalives are used more often, and the lingering keepalives are both
leaks and prevent the tests from finishing.
Have keepalives poll for their parent process ID and exit when it
changes, so they can clean themselves up. The polling frequency can be
low.
There is no more race condition between parent and child with
regards to setting the process groups. Each child sets it for themselves
and then blocks indefinitely until the parent does what it needs to for
them (having waited for them to set their process groups). They are not
SIGCONT'd until the next process in the chain (if any) starts so that
that process can join their process group and open the pipes.
I'm starting to wonder if IWYU is worth the effort. Nonetheless, this
makes it lint clean on macOS and reduces the number of warnings on
FreeBSD and Linux.
If an interactive shell has its tty invalidated attempts to write to
stdout or stderr can trigger this bug:
https://sourceware.org/bugzilla/show_bug.cgi?id=20632
Avoid that by reopening the stdio streams on /dev/null if we're getting
an ENOTTY error when trying to do things like give or take ownership of
the tty.
This includes some unrelated style cleanups but including them seems
reasonable.
Fixes#3644
Remove the "make iwyu" build target. Move the functionality into the
recently introduced lint.fish script. Fix a lot, but not all, of the
include-what-you-use errors. Specifically, it fixes all of the IWYU errors
on my OS X server but only removes some of them on my Ubuntu 14.04 server.
Fixes#2957
This change moves source files into a src/ directory,
and puts object files into an obj/ directory. The Makefile
and xcode project are updated accordingly.
Fixes#1866
