I am really not a fan of full code lines passed to macros as parameters.
Let's get rid of the 3rd parameter of FOREACH_OPTION() hence:
1. Let's return errors just as a regular value (though a negative one),
that can be handled via a OPTION_ERROR case statement for the switch.
This normalizes handling of the error, just like any other event
returned by the option parser.
2. In order to avoid exploding the amount of boilerplate in each use
(that just propagates the error on OPTION_ERROR), let's then
introduce an explicit FOREACH_OPTION_OR_RETURN(), that returns from
the calling function on its own (and makes that clear in the name).
Together this cleans up, normalizes the logic and shortens the code.
It was requested to make the 'c', 'opt', and 'arg' params the same, i.e.
defined through the FOREACH_OPTION macro. But we can't do that easily,
because 'c' was defined in the for loop definition, and we can only
define variables of the same type in that way. Also, in some cases we
need only 'c', in other cases with need 'c' and 'arg, in some cases 'c'
and 'opt', and in other cases all three. We'd need to either
conditionalize or mark those variables with _unused_ to deal with
compiler warnings. But a different approach works quite nicely: add
state.opt and state.arg to show the current option and it's argument.
(The short names are picked on purpose to reduce verbosity since those
are used a lot.)
We generally want to print an error message if table_print()
fails. Add a helper function for this and use it consistently.
This does one of the three things depending on the call site:
- a no-change reformatting of the code
- change from a custom message to the generic one
- addition of the error message where previously none was printed
In the third case, the actual use impact is very small, since the
table formatting is very unlikely to fail. But if it did, we would
often return an error without any message whatsoever, which we
never want to do.
Almost all callers of table_print() specify stdout or NULL (equivalent
to stdout) as the output stream. Simplify things by not requiring the
the stream to be specified.
In almost all cases, the printing of the table is surrounded by normal
printfs() that don't do explicit flushing and for which we don't check
the output stream status. Let's simplify most callers and skip this
step. The reason is not so much to avoid the extra step itself, but
instead to avoid the _handling_ of the potential failure. We generally
only want to print an error message for ENOMEM and other "internal"
errors, so strictly speaking we should filter out the errors from the
stream. By skipping the flush&check step we implicitly do this.
--help output changes: description is now highlighted, "Options:" header
added, option order follows declaration order, column width is auto-computed.
Co-developed-by: Claude <claude@anthropic.com>
This commit cleans up the includes for all the small tools across
the tree.
A few cases of returning EXIT_SUCCESS are replaced with returning
0 to avoid including <stdlib.h>.
Split out of #37344.
Now that the necessary functions from log.h have been moved to macro.h,
we can stop including log.h in macro.h. This requires modifying source
files all over the tree to include log.h instead.
These days we have a mechanism for safely returning errnos in enum
types, via definining -ERRNO_MAX as one special enu value. Let's use
that for Virtualization.
No change in behaviour, just some typesafety improvement.
In general we almost never hit those asserts in production code, so users see
them very rarely, if ever. But either way, we just need something that users
can pass to the developers.
We have quite a few of those asserts, and some have fairly nice messages, but
many are like "WTF?" or "???" or "unexpected something". The error that is
printed includes the file location, and function name. In almost all functions
there's at most one assert, so the function name alone is enough to identify
the failure for a developer. So we don't get much extra from the message, and
we might just as well drop them.
Dropping them makes our code a tiny bit smaller, and most importantly, improves
development experience by making it easy to insert such an assert in the code
without thinking how to phrase the argument.
I think this formatting was originally used because it simplified
adding new options to the help messages. However, these days, most
tools their help message end with "\nSee the %s for details.\n" so
the final line almost never has to be edited which eliminates the
benefit of the custom formatting used for printf() help messages.
Let's make things more consistent and use the same formatting for
printf() help messages that we use everywhere else.
Prompted by https://github.com/systemd/systemd/pull/18355#discussion_r567241580
Presently, CLI utilities such as systemctl will check whether they have a tty
attached or not to decide whether to parse /proc/cmdline or EFI variable
SystemdOptions looking for systemd.log_* entries.
But this check will be misleading if these tools are being launched by a
daemon, such as a monitoring daemon or automation service that runs in
background.
Make log handling of CLI tools uniform by never checking /proc/cmdline or EFI
variables to determine the logging level.
Furthermore, introduce a new log_setup_cli() shortcut to set up common options
used by most command-line utilities.
When emitting the calendarspec warning we want to see some color.
Follow-up for 04220fda5c.
Exceptions:
- systemctl, because it has a lot hand-crafted coloring
- tmpfiles, sysusers, stdio-bridge, etc, because they are also used in
services and I'm not sure if this wouldn't mess up something.
Ideally, coccinelle would strip unnecessary braces too. But I do not see any
option in coccinelle for this, so instead, I edited the patch text using
search&replace to remove the braces. Unfortunately this is not fully automatic,
in particular it didn't deal well with if-else-if-else blocks and ifdefs, so
there is an increased likelikehood be some bugs in such spots.
I also removed part of the patch that coccinelle generated for udev, where we
returns -1 for failure. This should be fixed independently.
This way, we can extend the macro a bit with stuff pulled in from other
headers without this affecting everything which pulls in macro.h, which
is one of our most basic headers.
This is just refactoring, no change in behaviour, in prepartion for
later changes.
This is a bit like the info link in most of GNU's --help texts, but we
don't do info but man pages, and we make them properly clickable on
terminal supporting that, because awesome.
I think it's generally advisable to link up our (brief) --help texts and
our (more comprehensive) man pages a bit, so this should be an easy and
straight-forward way to do it.
These lines are generally out-of-date, incomplete and unnecessary. With
SPDX and git repository much more accurate and fine grained information
about licensing and authorship is available, hence let's drop the
per-file copyright notice. Of course, removing copyright lines of others
is problematic, hence this commit only removes my own lines and leaves
all others untouched. It might be nicer if sooner or later those could
go away too, making git the only and accurate source of authorship
information.
This part of the copyright blurb stems from the GPL use recommendations:
https://www.gnu.org/licenses/gpl-howto.en.html
The concept appears to originate in times where version control was per
file, instead of per tree, and was a way to glue the files together.
Ultimately, we nowadays don't live in that world anymore, and this
information is entirely useless anyway, as people are very welcome to
copy these files into any projects they like, and they shouldn't have to
change bits that are part of our copyright header for that.
hence, let's just get rid of this old cruft, and shorten our codebase a
bit.
Files which are installed as-is (any .service and other unit files, .conf
files, .policy files, etc), are left as is. My assumption is that SPDX
identifiers are not yet that well known, so it's better to retain the
extended header to avoid any doubt.
I also kept any copyright lines. We can probably remove them, but it'd nice to
obtain explicit acks from all involved authors before doing that.
Various things don't work when we're running in a user namespace, but it's
pretty hard to reliably detect if that is true.
A function is added which looks at /proc/self/uid_map and returns false
if the default "0 0 UINT32_MAX" is found, and true if it finds anything else.
This misses the case where an 1:1 mapping with the full range was used, but
I don't know how to distinguish this case.
'systemd-detect-virt --private-users' is very similar to
'systemd-detect-virt --chroot', but we check for a user namespace instead.
This also allows us to drop build.h from a ton of files, hence do so.
Since we touched the #includes of those files, let's order them properly
according to CODING_STYLE.
Introduce a proper enum, and don't pass around string ids anymore. This
simplifies things quite a bit, and makes virtualization detection more
similar to architecture detection.
This patch removes includes that are not used. The removals were found with
include-what-you-use which checks if any of the symbols from a header is
in use.
As a followup to 086891e5c1 "log: add an "error" parameter to all
low-level logging calls and intrdouce log_error_errno() as log calls
that take error numbers", use sed to convert the simple cases to use
the new macros:
find . -name '*.[ch]' | xargs sed -r -i -e \
's/log_(debug|info|notice|warning|error|emergency)\("(.*)%s"(.*), strerror\(-([a-zA-Z_]+)\)\);/log_\1_errno(-\4, "\2%m"\3);/'
Multi-line log_*() invocations are not covered.
And we also should add log_unit_*_errno().
getopt is usually good at printing out a nice error message when
commandline options are invalid. It distinguishes between an unknown
option and a known option with a missing arg. It is better to let it
do its job and not use opterr=0 unless we actually want to suppress
messages. So remove opterr=0 in the few places where it wasn't really
useful.
When an error in options is encountered, we should not print a lengthy
help() and overwhelm the user, when we know precisely what is wrong
with the commandline. In addition, since help() prints to stdout, it
should not be used except when requested with -h or --help.
Also, simplify things here and there.
After all, we ended up calling detect_container() more often than
detect_virtualization(), hence the former one should cache the results,
since the latter is only a wrapper around the former.
