tree-wide: remove Emacs lines from all files This should be handled fine now by .dir-locals.el, so need to carry that stuff in every file.

util-lib: make sure usec_sub() doesn't degrade USEC_INFINITY As suggested in: https://github.com/systemd/systemd/pull/2542#issuecomment-181877820

time-util: make timespec_load_nsec() static The timespec_load_nsec() function has no callers outside of the time-util.c, so we can make it static.

time-util: introduce usec_sub() The dual_timestamp_from_realtime(), dual_timestamp_from_monotonic() and dual_timestamp_from_boottime_or_monotonic() shares the same code for comparison given ts with delta. Let's move it to the separate inline function to prevent code duplication.

util: add check that makes sure time_t and TIME_T_MAX work the way we assume they do

util: add usec_add() which adds two usec_t values with overflow handling

basic: include only what we use This is a cleaned up result of running iwyu but without forward declarations on src/basic.

time-util: add parse_time(), which is like parse_sec() but allows specification of default time unit if none is specified This is useful if we want to parse RLIMIT_RTTIME values where the common UNIX syntax is without any units but refers to a non-second unit (µs in this case), but where we want to allow specification of units.

Time-util: introduce usec to jiffies

basic: add mktime_or_timegm and localtime_or_gmtime_r to time-util.h. They take an extra argument `bool utc`.

basic: nicer xsprintf and xstrftime assert messages It's nicer if the assertion failure message from a bad use of xsprintf actually mentions xsprintf instead of the expression the macro is implemented as. The assert_message_se macro was added in the previous commit as an internal helper, but it can also be used for customizing assertion failure messages like in this case. Example: char buf[10]; xsprintf(buf, "This is a %s message.\n", "long"); Before: Assertion '(size_t) snprintf(buf, ELEMENTSOF(buf), "This is a %s message.\n", "long") < ELEMENTSOF(buf)' failed at foo.c:6, function main(). Aborting. After: Assertion 'xsprintf: buf[] must be big enough' failed at foo.c:6, function main(). Aborting.

cgtop: major modernizations In preparation of the unified cgroup support, let's clean up cgtop: a) rework time code to be based on "nsec_t" rather than "struct timespec" b) Introduce long option --order= for selecting ordering c) count number of processes only in the main hierarchy, don't bother with the controller hierarchies. We don't allow orthogonal hierarchies in systemd anymore, hence there's no point to check the other hierarchies. d) Deal with non-monotonic cpuacct values (see #749) e) When sorting groups, don't do prefix compare when ordering by number of tasks, since this is not accumulative for all children. f) Actually make --cpu without parameter work g) Don't output control characters when we get them as input. Fixes #749.

time-util: add new get_timezone() call to get local timezone Let's move the timedated-specific code to time-util.h and make it generic.

machined: introduce pseudo-machine ".host" refererring to the host system Some of the operations machined/machinectl implement are also very useful when applied to the host system (such as machinectl login, machinectl shell or machinectl status), hence introduce a pseudo-machine by the name of ".host" in machined that refers to the host system, and may be used top execute operations on the host system with. This copies the pseudo-image ".host" machined already implements for image related commands. (This commit also adds a PK privilege for opening a PTY in a container, which was previously not accessible for non-root.)

build-sys: split internal basic/ library from shared/ basic/ can be used by everything cannot use anything outside of basic/ libsystemd/ can use basic/ cannot use shared/ shared/ can use libsystemd/