UAPI.15 requires:
* No C0 Control Characters (`\x00-\x1f`)
* No DEL character (`\x7f`)
The following would be nice, but requires a `sed` implementation that is
aware of UTF-8: `-e $'y/\x00-\x1f\x7f/␀-␟␡/'`.
References:
[0] https://uapi-group.org/specifications/specs/osc_context/#general-syntax
Bash does not provide an easy way to discern if an exit status came from
a signal, or was a legitimate non-zero exit (i.e. a failure). It can be
done, by using job control or by invoking another program; however, such
approaches require modifying the command entered by a user and are, thus,
invasive and risky.
Since an exit status of 129 on a command could either indicate it exited
cleanly with `exit(129)` or was interrupted by `SIGHUP`, the osc context
should report both possibilities, to acknowledge our uncertainty. Given
we have no idea what happened, besides an unsuccessful exit, the exit is
described as `exit=failure`.
Moreover, discerning between an `interrupt` and a `crash` with a command
likely involves categorizing every signal. It is fairly obvious `SIGINT`
is an interrupt and also obvious, IMO, that `SIGSEGV` is a crash. Avoid
the complication (and potential disagreements) by using the encompassing,
generic value — one that remains true if no signal occurred.
References:
[0] https://stackoverflow.com/a/66431355
Symlinks to files inside sysconfdir are now only installed if
ìnstall_sysconfdir=true (which is the default).
If sshconfdir,sshdconfdir,shellprofiledir are not inside sysconfdir and
install_sysconfidr=false, these symlinks are still installed to the
configured directory.
Let's do the check early and skip most of the file if appropriate. Also, treat
missing $TERM same as "dumb". We're almost certainly at a dump terminal in that
case.
In https://github.com/systemd/systemd/issues/39114 users are reporting
that our script overrides PROMPT_COMMAND that they had. After looking
at /etc/bashrc in Fedora, I see that it only sets PROMPT_COMMAND if
[ -z "$PROMPT_COMMAND" ]. Let's adjust the script so this continues to
work.
Fixes https://github.com/systemd/systemd/issues/39114.
(This is a bit of a stretch. 39114 was originally about SecureCRT,
but that was resolved in SecureCRT. But there was a lot of dicussion
about the prompt being overriden, which this commit should fix.)
While we can safely assume that `/proc/sys/kernel/random/boot_id`
exists, the same can't be said for `/etc/machine-id` in environments
where systemd is installed, but not running. An example would be OCI
containers like with the official Arch Linux image, see [0].
Without this check the prompt would constantly output `/etc/machine-id:
no such file or directory` with the OSC events introduced in dadbb34
(v258).
[0] https://gitlab.archlinux.org/archlinux/archlinux-docker/-/issues/107
Now our baseline of meson is 0.62, hence install_symlink() can be used.
Note, install_symlink() implies install_emptydir() for specified
install_dir. Hence, this also drops several unnecessary
install_emptydir() calls.
Note, the function currently does not support 'relative' and 'force' flags,
so several 'ln -frsT' inline calls cannot be replaced.
If - for whatever reason - a script uses set -u (nounset) and includes
/etc/profile.d/70-systemd-shell-extra.sh (e.g. transitively via
/etc/profile) the script would fail with:
/etc/profile.d/70-systemd-shell-extra.sh: line 15: SHELL_PROMPT_PREFIX: unbound variable
For example:
$ cat > foo.sh <<EOF
#!/bin/sh
set -u
source /etc/profile
EOF
$ chmod 700 foo.sh
$ ./foo.sh
/etc/profile.d/70-systemd-shell-extra.sh: line 15: SHELL_PROMPT_PREFIX: unbound variable
Fix this by using shell parameter substitution[^1] (which is a POSIX
shell concept) to set the $SHELL_* variables to the empty string if
undefined.
[^1]: https://pubs.opengroup.org/onlinepubs/9699919799.2018edition/utilities/V3_chap02.html
Frantisek Sumsal
Chris Lindee
nikstur
Lennart Poettering
Yu Watanabe
Zbigniew Jędrzejewski-Szmek
Justin Kromlinger
Tobias Klauser