core: don't reset /dev/console if stdin/stdout/stderr as passed as fd in a transient service Otherwise we might end resetting /dev/console all the time when a transient service starts or stops. Fixes #2377 Fixes #2198 Fixes #2061

basic/terminal-util: introduce SYSTEMD_COLORS environment variable ... to determine if color output should be enabled. If the variable is not set, fall back to using on_tty(). Also, rewrite existing code to use colors_enabled() where appropriate.

tree-wide: check if errno is greater then zero gcc is confused by the common idiom of return errno ? -errno : -ESOMETHING and thinks a positive value may be returned. Replace this condition with errno > 0 to help gcc and avoid many spurious warnings. I filed a gcc rfe a long time ago, but it hard to say if it will ever be implemented [1]. Both conventions were used in the codebase, this change makes things more consistent. This is a follow up to bcb161b0230f. [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61846

basic: re-sort includes My previous patch to only include what we use accidentially placed the added inlcudes in non-sorted order.

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

doc: correct punctuation and improve typography in documentation

util-lib: split out allocation calls into alloc-util.[ch]

util-lib: move status printing stuff into src/core/ It's very specific to the core, and not used elsewhere, hence move it out of terminal-util.[ch].

util-lib: split stat()/statfs()/stavfs() related calls into stat-util.[ch]

util-lib: move a number of fs operations into fs-util.[ch]

util-lib: split string parsing related calls from util.[ch] into parse-util.[ch]

socket-util: move remaining socket-related calls from util.[ch] to socket-util.[ch]

util-lib: split out IO related calls to io-util.[ch]

util-lib: split out fd-related operations into fd-util.[ch] There are more than enough to deserve their own .c file, hence move them over.

util-lib: split our string related calls from util.[ch] into its own file string-util.[ch] There are more than enough calls doing string manipulations to deserve its own files, hence do something about it. This patch also sorts the #include blocks of all files that needed to be updated, according to the sorting suggestions from CODING_STYLE. Since pretty much every file needs our string manipulation functions this effectively means that most files have sorted #include blocks now. Also touches a few unrelated include files.

util: minor modernization of vt_disallocate()

util: do not reset terminal in acquire_terminal() Before, we'd always reset acquired terminals, which is not really desired, as we expose a setting TTYReset= which is supposed to control whether the TTY is reset or not. Previously that setting would only enable a second resetting of the TTY, which is of course pointless... Hence, move the implicit resetting out of acquire_terminal() and make the callers do it if they need it.

machined: when opening a shell via machined, pass tty fds in With this change we'll open the shell's tty right from machined and then pass it to the transient unit we create. This way we make sure the pty is opened exactly as long as the transient service is around, and no longer, and vice versa. This way pty forwarders do not have to deal with EIO problems due to vhangup, as the pty is open all the time from the point we set things up to the point where the service goes away.

basic: move two more terminal-related calls into terminal-util.[ch]

logind: remove warn_melody() logic The internal speaker is usually not available on modern latops that support suspend, and even if it is available in the hardware, most distributions turned support for it off in the kernel. And even if it is enabled, it's probably still a bad idea to make use of it for the suspend-failures. If anything a proper sound should be played. Long story short, let's remove support of this anachronism.

core: rework crash handling This introduces a new systemd.crash_reboot=1 kernel command line option that triggers a reboot after crashing. This also cleans up crash VT handling. Specifically, it cleans up the configuration setting, to be between 1..63 or a boolean. This is to replace the previous logic where "-1" meant disabled. We continue to accept that setting, but only document the boolean syntax instead. This also brings the documentation of the default settings in sync with what actually happens. The CrashChVT= configuration file setting is renamed to CrashChangeVT=, following our usual logic of not abbreviating unnecessarily. The old setting stays support for compat reasons. Fixes #1300

cgtop: underline table header Let's underline the header line of the table shown by cgtop, how it is customary for tables. In order to do this, let's introduce new ANSI underline macros, and clean up the existing ones as side effect.

machined: introduce a ptsname_namespace() call and make use of it The call is like ptsname() but does not assume the pty path was accessible in the local namespace. It uses the same internal ioctl though.

terminal-util: no real reason to assert on O_CREAT That's just handle this as a normal error.

terminal-util: cast a couple of ioctl()s to void

terminal-util: when resetting terminals, don't wait for carrier In case of non-CLOCAL lines (i.e. those with carrier detect configured) we shouldnt wait for a carrier if all we try to do is reset the TTY. Hence, whenever we open such a TTY pass O_NONBLOCK. Note that we continue to open ttys we intend to write to without O_ONBLOCK, we only add it in cases we invoke ioctl()s or other terminal operations without reading or writing to the device. Fixes #835.

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/