This macro will read a pointer of any type, return it, and set the
pointer to NULL. This is useful as an explicit concept of passing
ownership of a memory area between pointers.
This takes inspiration from Rust:
https://doc.rust-lang.org/std/option/enum.Option.html#method.take
and was suggested by Alan Jenkins (@sourcejedi).
It drops ~160 lines of code from our codebase, which makes me like it.
Also, I think it clarifies passing of ownership, and thus helps
readability a bit (at least for the initiated who know the new macro)
Let's replace usage of fputc_unlocked() and friends by __fsetlocking(f,
FSETLOCKING_BYCALLER). This turns off locking for the entire FILE*,
instead of doing individual per-call decision whether to use normal
calls or _unlocked() calls.
This has various benefits:
1. It's easier to read and easier not to forget
2. It's more comprehensive, as fprintf() and friends are covered too
(as these functions have no _unlocked() counterpart)
3. Philosophically, it's a bit more correct, because it's more a
property of the file handle really whether we ever pass it on to another
thread, not of the operations we then apply to it.
This patch reworks all pieces of codes that so far used fxyz_unlocked()
calls to use __fsetlocking() instead. It also reworks all places that
use open_memstream(), i.e. use stdio FILE* for string manipulations.
Note that this in some way a revert of 4b61c87511.
For files which are vital to boot
1. Avoid opening any window where power loss will zero them out or worse.
I know app developers all coded to the ext3 implementation, but
the only formal documentation we have says we're broken if we actually
rely on it. E.g.
* `man mount`, search for `auto_da_alloc`.
* http://www.linux-mtd.infradead.org/faq/ubifs.html#L_atomic_change
* https://thunk.org/tytso/blog/2009/03/15/dont-fear-the-fsync/
2. If we tell the kernel we're interested in writing them to disk, it will
tell us if that fails. So at minimum, this means we play our part in
notifying the user about errors.
I refactored error-handling in `udevadm-hwdb` a little. It turns out I did
exactly the same as had already been done in the `systemd-hwdb` version,
i.e. commit d702dcd.
One of the benefits of updating a file "atomically", is to avoid losing the
old version. For example, if we run out of disk space half-way through.
Fix localed to enjoy this benefit.
As a follow-up for db3f45e2d2 let's do the
same for all other cases where we create a FILE* with local scope and
know that no other threads hence can have access to it.
For most cases this shouldn't change much really, but this should speed
dbus introspection and calender time formatting up a bit.
This adds (undocumented) environment variables SYSTEMD_KBD_MODEL_MAP
and SYSTEMD_LANGUAGE_FALLBACK_MAP, which, if set, override compiled-in
locations of those two files.
Instead of skipping tests when the maps are not installed, just use
the one from the source dir. We still cannot do the mappings the other
way if /usr/lib/kbd/keymaps is not present, so truncate the tests in
that case.
Also tweak the debug messages a bit to make it easier to see
which function is failing.
As discovered by Adam Williamson in
https://bugzilla.redhat.com/show_bug.cgi?id=1333998#c32, after the changes in
81fd105a5f we would only match compound layouts, i.e. a comma would be
required after 'ru' to match. This seems wrong, and we should match single
layouts like too. So 'ru', 'ru,us' now both match.
startswith_comma is changed to not require a comma, i.e. check that the prefix
matches until a comma or the end of the string. Note that startswith_comma is
called twice. At the first site, we check that strings are not equal
beforehand, so this change to startswith_comma has no effect. At the second
site, it does have an effect, as described above.
Rework the code a bit where find_converted_keymap cannot (and should not) be
called with a null layout, so streq can be used instead of streq_ptr, etc.
Note that the behaviour of vconsole_convert_to_x11 and x11_convert_to_vconsole
is not symmetrical. When the latter cannot find a match, it simply makes the
vconsole mapping empty. But vconsole_convert_to_x11 leaves the x11 layout
unchanged. I don't know what the proper solution is here, so I'm just adding
more verbose logging without changing the logic.
I was puzzled why "localectl set-keymap pl" does not change the X11 keymap.
Output a message at notice level, becuase not converting the X11 keymap
is most likely an error. We usually do not output non-debug messages
from "library" code, but this isn't really library code, it's split out
to a separate file only to allow it to be called from tests.
(pl is not converted because we only have a mapping for pl2. This is
intentional, even though we might want to change this. In any case, the
conversion code works correctly.)
When converting an empty x11 variant, we would not delete vconsole mapping
properly.
find_legacy_keymap() is made non-static. I think it's important to be able to
test it. In principle we could also test it through the higher-level interface
of x11_convert_to_vconsole, but x11_convert_to_vconsole also uses
find_converted_keymap, and it's better to test at this lower level.
Note that find_legacy_keymap might be a bit of a misnomer, because we'd probably
want to keep kbd-model-map even if the "legacy" layouts went away. So we might
want to change this name, but I'm leaving that for another commit.
Lennart Poettering