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.
This is useful so that callers know whether anything at all and how much
was flushed.
This patches through users of this functions to ensure that the return
values > 0 which may be returned now are not propagated in public APIs.
Also, users that ignore the return value are changed to do so explicitly
now.
In libudev (which es much older code than the rest of systemd), we
propagate errors in functions not returning an int, via (positive) errno
(i.e. libc-style), and as negative Exyz values in those returning an int
(much preferred, i.e. Linux kernel style). Let's fix up a few place,
where this was incorrectly done, or not done at all.
Fixes: #6613
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.
For two releases those exported with version 183 by mistake, and then
they were fixed to have version 215 (015419c0df libudev: fix symbol
version for udev_queue_flush() and udev_queue_get_fd()). But that
breaks ABI compatibility for binaries compiled with udev from before
that commit. There most likely very few such binaries, if any, but as
a matter of principle we should export the old symbols too, in order
to keep full compatibility.
The way the kernel namespaces have been implemented breaks assumptions
udev made regarding uevent sequence numbers. Creating devices in a
namespace "steals" uevents and its sequence numbers from the host. It
confuses the "udevadmin settle" logic, which might block until util a
timeout is reached, even when no uevent is pending.
Remove any assumptions about sequence numbers and deprecate libudev's
API exposing these numbers; none of that can reliably be used anymore
when namespaces are involved.
Returning anything else but NULL would suggest the caller's reference
might still be valid, but it isn't, because the caller just invoked
_unref() after all.
This turns the return value into a typesafe shortcut that allows
unreffing and resetting a reference in one line. In contrast to
solutions for this which take a pointer to a pointer to accomplish the
same this solution is just syntactic sugar the developer can make use of
but doesn't have to, and this is particularly useful when immediately
unreffing objects returned by function calls.
There is no apparent justification for using util_strscpyl
on the filename since it's a plain hardcoded path.
Older versions used:
util_strscpyl(filename, sizeof(filename), SOME_DIR, "/queue.bin", NULL);
and when changed nobody bothered to simplify it.