This code seems to work quickly and nicely for a bunch of modern
terminals. Setting $TERM automatically removes an common annoyance for
users. This code will not work for all terminal emulators, but by adding
it in systemd we'll entice maintainers of those terminals to add support
for the sequences. For the terminals that don't support the sequence, we
get a bit of a slowdown of `< 1 ms`, which seems hardly noticeable. The
user can always set TERM explicitly to avoid this if upgrading to a
newer terminal emulator is not possible.
Closes https://github.com/systemd/systemd/issues/36994.
query_term_for_tty() is used in two places: in fixup_environment(),
which affects PID1 itself, and in build_environment(), which affects
spawned services. There is obviously some cost to the extra call,
but I think it's worthwhile to do it. When $TERM is set incorrectly,
basic output works OK, but then there are various annoying corner
cases. In particular, we get the support for color (or lack of it)
wrong, and when output is garbled, users are annoyed. Things like
text editors are almost certain to behave incorrectly. Testing in
test-terminal-util indicates that the time required to make a successful
query is on the order of a dozen microseconds, and an unsuccessful
query costs as much as our timeout, i.e. currently 1/3 ms. I think
this is an acceptable tradeoff.
No caching is used, because fixup_environment() is only called once,
and the other place in build_environment(), only affects services
which are connected to a tty, which is only a handful of services,
and often only started in special circumstances.
Fixes https://github.com/systemd/systemd/issues/36994.
With c960ca2be1, logind triggers uevents
for devices with uaccess tag, and waits for the events being processed
by udevd.
However, logind received not all triggered events, and might lose some
events. That causes session and user state file not updated, and many
desktop environment application handled the session and user were inactive.
This introduces one more device monitor instance which monitor events
for devices with 'uaccess' tag. Hence, all triggered events will be
recieved by logind, and session and user state file will be updated.
Follow-up for c960ca2be1.
Fixes#37579.
Two constants are described in the man page, but are not defined by a header.
The third constant is described in the kernel docs. Use explicit values to
show that those are values are defined externally.
A new core_pattern specifier was added, %F, to provide a PIDFD
to the usermode helper process referring to the crashed process.
This removes all possible race conditions, ensuring only the
crashed process gets inspected by systemd-coredump.
The check looks plausible, but when I started checking whether it needs
to be lowered for the recent changes, I realized that it doesn't make
much sense.
context_parse_iovw() is called from a few places, e.g.:
- process_socket(), where the other side controls the contents of the
message. We already do other checks on the correctness of the message
and this assert is not needed.
- gather_pid_metadata_from_argv(), which is called after
inserting MESSAGE_ID= and PRIORITY= into the array, so there is no
direct relation between _META_ARGV_MAX and the number of args in the
iovw.
- gather_pid_metadata_from_procfs(), where we insert a bazillion fields,
but without any relation to _META_ARGV_MAX.
Since we already separately check if the required stuff was set, drop this
misleading check.
The kernel provides %d which is documented as
"dump mode—same as value returned by prctl(2) PR_GET_DUMPABLE".
We already query /proc/pid/auxv for this information, but unfortunately this
check is subject to a race, because the crashed process may be replaced by an
attacker before we read this data, for example replacing a SUID process that
was killed by a signal with another process that is not SUID, tricking us into
making the coredump of the original process readable by the attacker.
With this patch, we effectively add one more check to the list of conditions
that need be satisfied if we are to make the coredump accessible to the user.
Reportedy-by: Qualys Security Advisory <qsa@qualys.com>
In principle, %d might return a value other than 0, 1, or 2 in the future.
Thus, we accept those, but emit a notice.
Add endpoint for listing boots. Output format mimics `journalctl
--list-boots -o json`, so it's a plain array containing index, boot ID
and timestamps of the first and last entry. Initial implementation
returns boots ordered starting with the current one and doesn't allow
any filtering (i.e. equivalent of --lines argument).
Fixes: #37573
A "string" is a concept in C. In a text-based API, this is implicit, especially
if we say that something was "formatted". So change occurences of "decimal
string" to just "decimal". Similarly, "numerics" is unclear, say "digits".
Also, a "timestamp is in a clock" just sounds wrong. Reword those sentences.
This renames e.g. struct bus_body_part -> BusMessageBodyPart to
follow our usual coding style. Also, several struct and enum
declarations are moved to relevant headers.
Also, this introduces bus-forward.h.
