tests: fix newlines in skip message

tests: turn check if manager cannot be intialized into macro We need to check the same thing in multiple tests. Use a shared macro to make it easier to update the list of errnos. Change the errno code for "unitialized cgroup fs" for ENOMEDIUM. Exec format error looks like something more serious. This fixes test-execute invocation in mock.

test-path: move all related test files to a specific directory To avoid polluting test/

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

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

tests: Skip tests which need to access /sys/fs/cgroup if that is not available Commit efdb023 ("core: unified cgroup hierarchy support") introduced a new error ENOEXEC in cg_unified() if /sys/fs/cgroup/ is not available. Adjust the "skip" checks in various tests accordingly. Add a corresponding "skip" check to test-bus-creds as well, as sd_bus_creds_new_from_pid() now calls cg_unified() as well. This re-fixes "make check" in build chroots without /sys/fs/cgroup. https://github.com/systemd/systemd/issues/1132

core: rename SystemdRunningAs to ManagerRunningAs It's primarily just a property of the Manager object after all, and we try to refer to PID 1 as "manager" instead of "systemd", hence let's to stick to this here too.

test: test-path and test-execute only need units in test/

util: rework rm_rf() logic - Move to its own file rm-rf.c - Change parameters into a single flags parameter - Remove "honour sticky" logic, it's unused these days

fix gcc warnings about uninitialized variables like: src/shared/install.c: In function ‘unit_file_lookup_state’: src/shared/install.c:1861:16: warning: ‘r’ may be used uninitialized in this function [-Wmaybe-uninitialized] return r < 0 ? r : state; ^ src/shared/install.c:1796:13: note: ‘r’ was declared here int r; ^

util: rework strappenda(), and rename it strjoina() After all it is now much more like strjoin() than strappend(). At the same time, add support for NULL sentinels, even if they are normally not necessary.

test-path: do not skip tests if we are not root We can properly run the tests without being root

tree-wide: spelling fixes https://github.com/vlajos/misspell_fixer https://github.com/torstehu/systemd/commit/b6fdeb618cf2f3ce1645b3315f15f482710c7ffa Thanks to Torstein Husebo <torstein@huseboe.net>.

manager: allow test run to catch SIGCHLD events Otherwise we cannot know when a service exited

tests: add test-path It tests all available directives of Path units: - PathChanged - PathModified - PathExists - PathExisysGlob - DirectoryNotEmpty - MakeDirectory - DirectoryMode - Unit