Fix#5133 changed builtins to acquire the terminal, but this regressed
caused fish to be stopped when running in background via `sudo fish`.
Fix this by only acquiring the terminal if the terminal was owned by the
builtin's pgroup.
Fixes#5147
When running a builtin, if we are an interactive shell and stdin is a tty,
then acquire ownership of the terminal via tcgetpgrp() before running the
builtin, and set it back after.
Fixes#4540
While supported by gcc and clang, \e is a gcc-specific extension and not
formally defined in the C or C++ standards.
See [0] for a list of valid escapes.
[0]: https://stackoverflow.com/a/10220539/17027
Turns out the process-exit is only ever used in conjunction with
`%self`. Make that explicit by just adding a new "fish_exit" event,
and deprecate the general process-exit machinery.
Fixes#4700.
This concerns block nodes with redirections, like
begin ... end | grep ...
Prior to this fix, we passed in a pointer to the node. Switch to passing
in the tnode and parsed source ref. This improves type safety and better
aligns with the function-node plans.
There were several issues with the way that the include tests for curses.h
were being done that were ultimately causing fish to use the headers from
ncurses but link against curses on platforms that provide an actual
libcurses.so that isn't just a symlink to libncurses.so
In particular, the old code was first testing for curses's cureses.h and then
falling back to libncurses's implementation of the same - but that logic was
reversed when it came to including term.h, in which case it was testing for
the ncurses term.h and falling back to the curses.h header. Long story short,
while cmake will link against libcurses.so if both libcurses.so and
libncurses.so are present (unless CURSES_NEED_NCURSES evaluates to TRUE, but
that makes ncurses a hard requirement), but we were brining in some of the
defines from the ncurses headers, causing SIGSEGV panics when fish ultimately
tried to access variables that weren't exported or were mapped to undefined
areas of memory in the other library.
Additionally it is an error to include termios.h prior to including the plain
Jane curses.h (not ncurses/curses.h), causing errors about unimplemented types
SGTTY/chtype. So far as I can tell, both curses.h and ncurses/curses.h pull in
termios.h themselves so it shouldn't even be necessary to manually include it,
but I have just moved its #include below that of curses.h
No longer using RAII wrappers around pthread_mutex_t and pthread_cond_t
in favor of the C++11 std::mutex, std::recursive_mutex, and
std::condition_variable data types.
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.
Setting the process group in a fork/exec scenario is a well-documented
race condition in pretty much any job control mechanism [0] [1]. The
Wikipedia article contradicts the glibc article and suggests that the
best approach is for the parent to wait for the child to become the
process group leader, while the glibc article suggests that both should
make it so (which is what fish did previously). However, I'm running
into cases where tcsetpgrp is causing an EPERM error, which it isn't
documented to do except if the session id for the calling process
differs from that of the target process group (which is never the case
in fish since they are all part of the same session), which should cause
a _different_ error (SIGTTOU to be sent to all members of the calling
process' group).
In all cases, this is easily remedied by checking if the process group
in question is already in control of the terimnal. There's still the
off-chance that in the time between we check that and the time that the
command completes that situation may have changed, but the parent
process is supposed to ignore the result of this call if it errors out.
[0]: https://en.wikipedia.org/wiki/Process_group
[1]: https://www.gnu.org/software/libc/manual/html_node/Launching-Jobs.html
PR #3691 made most calls to `signal_block()` and `signal_unblock()`
no-ops unless a magic env var is set when fish starts running. It's
been seven months since that change was made and no problems have been
reported. This finishes that work by removing those no-op function calls
and support for the magic env var in our next major release (which won't
happen till at least six months from now).
This implements `status is-breakpoint` that returns true if the current
shell prompt is displayed in the context of a `breakpoint` command.
This also fixes several bugs. Most notably making `breakpoint` a no-op if
the shell isn't interactive. Also, typing `breakpoint` at an interactive
prompt should be an error rather than creating a new nested debugging
context.
Partial fix for #1310
This came up in the context of issue #4068. This change makes it more
likely that the correct translation from english to another language
will be done for the "Job ... has {ended,stopped}" message.
0 is not a good default PGID, because it's possible for a kernel process
to have the PGID of 0 under Linux.
This meant that job_get_from_pid could return incorrect jobs, as the PGID
for internal, non-forked jobs was the same as kernel processes.
Avoid this by using an invalid PGID as the initial PGID.
It is possible for fish to not be the process group leader; avoid
signalling the process group containing the current process by checking
with getpgrp() rather than assuming that getpid() is enough.
This is the next step in determining whether we can disable blocking
signals without a good reason to do so. This makes not blocking signals
the default behavior. If someone finds a problem they can add this to
their ~/config/fish/config.fish file:
set FISH_NO_SIGNAL_BLOCK 0
Alternatively set that env var before starting fish. I won't be surprised
if people report problems. Till now we have relied on people opting in
to this behavior to tell us whether it causes problems. This makes the
experimental behavior the default that has to be opted out of. This will
give us a lot more confidence this change doesn't cause problems before
the next minor release.
Note that there are still a few places where we force blocking of
signals. Primarily to keep SIGTSTP from interfering with the shell in
response to manipulating the controlling tty. Bash is more selective
in the signals it blocks around the problematic syscalls (c.f., its
`git_terminal_to()` function). However, I don't see any value in that
refinement.
I recently upgraded the software on my macOS server and was dismayed to
see that cppcheck reported a huge number of format string errors due to
mismatches between the format string and its arguments from calls to
`assert()`. It turns out they are due to the macOS header using `%lu`
for the line number which is obviously wrong since it is using the C
preprocessor `__LINE__` symbol which evaluates to a signed int.
I also noticed that the macOS implementation writes to stdout, rather
than stderr. It also uses `printf()` which can be a problem on some
platforms if the stream is already in wide mode which is the normal case
for fish.
So implement our own `assert()` implementation. This also eliminates
double-negative warnings that we get from some of our calls to
`assert()` on some platforms by oclint.
Also reimplement the `DIE()` macro in terms of our internal
implementation.
Rewrite `assert(0 && msg)` statements to `DIE(msg)` for clarity and to
eliminate oclint warnings about constant expressions.
Fixes#3276, albeit not in the fashion I originally envisioned.
