Let's switch things around, and move the internals of safe_fork_full() into
pidref_safe_fork_full() and make safe_fork_full() a trivial wrapper on top
of pidref_safe_fork_full().
So far we'd leave the cursor at the end of the Press any key to proceed
message as long as the user didn't type in anything yet, and generated
the newline only after.
Let's switch this around: let's output the newline before.
This should make boot-time output nicer since it means concurrent output
while we wait will start at the beginning of line, and not in the middle.
This adds TAB-based auto-completion to various fields we query from the
user, such as locale, keymap, timezone, group membership.
It makes it a lot easier to quickly iterate through firstboot without
typing too much.
This modernizes the function a bit, and adds some bits:
1. whether to show numbers before entries is now optional, and if they
are shown they are displayed in grey.
2. a common prefix can now be grayed out (later useful for completion
support)
3. some variables have been named to clarify their purpose
4. the table display dimensions can now be auto-sized (by specifying
SIZE_MAX and number of columns and column width)
1. Make the message a bit more visible, by adding ANSI color. This
matters in particular during boot, where the message otherwise might
be overprinted by other output
2. Let's turn off terminal echo so that whatever key is entered is not
made visible on screen, and we can handle newline and other keys
reasonably uniformly.
CLONE_PIDFD was introduced in v5.2 and in sched.h in glibc-2.31 so
without this, building with older version fails with:
src/basic/raw-clone.h:41:108: error: 'CLONE_PIDFD' undeclared (first use in this function); did you mean 'CLONE_FILES'?
Added in 6140be90ec
However, when O_PATH fds are encountered we'd have to go by
/proc/self/fd/ still, since the kernel people are reluctant
to make the new syscalls work with them
(https://lore.kernel.org/linux-fsdevel/20250206-steril-raumplanung-733224062432@brauner/)
Hence getxattrat() and listxattrat() are not employed.
While at it, remove the discrepancy between path being NULL
and empty - I don't grok the "security issue" claimed earlier,
but nowadays even the kernel treats the two as identical:
e896474fe4
tty_is_vc() is more often than not used for simple "categorization"
than validity check. E.g. in logind, we first recognize the tty
"looks like vc", and then use vtnr_from_tty() where range check
is performed and vtnr is extracted. In such cases, we want to reject
invalid vtnr from clients rather than silently carry on, hence
let's remove bound check in tty_is_vc().
Fixes#36166
Replaces #36167 and #36175
Sometimes it's nice being able to store dev_t as pointer values in
hashmaps/tables, instead of having to allocate memory for them and using
devt_hash_ops. After all dev_t is weird on Linux/glibc: glibc defines it
as 64bit entity (which hence appears as something we cannot encode in a
pointer value for compat with 32bit archs) but it actually is 32bit in
the kernel apis. Hence we can safely cut off the upper 32bit, and still
retain compat with all archs.
But let's hide this in new macros, and validate this is all correct via
a test.
systemctl has a --job-mode= argument, and adding the same argument to
systemd-run is useful for starting transient scopes with dependencies.
For example, if a transient scope BindsTo a service that is stopping,
specifying --job-mode=replace will wait for the service to stop before
starting it again, while the default job mode of "fail" will cause the
systemd-run invocation to fail.
