core: add transient units

Transient units can be created via the bus API. They are configured via
the method call parameters rather than on-disk files. They are subject
to normal GC. Transient units currently may only be created for
services (however, we will extend this), and currently only ExecStart=
and the cgroup parameters can be configured (also to be extended).

Transient units require a unique name, that previously had no
configuration file on disk.

A tool systemd-run is added that makes use of this functionality to run
arbitrary command lines as transient services:

$ systemd-run /bin/ping www.heise.de

Will cause systemd to create a new transient service and run ping in it.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/core/load-fragment.c b/src/core/load-fragment.c
index 57c8156fdd..2b10d72ab3 100644
--- a/src/core/load-fragment.c
+++ b/src/core/load-fragment.c
@@ -2439,14 +2439,14 @@ static int load_from_path(Unit *u, const char *path) {
         if (null_or_empty(&st))
                 u->load_state = UNIT_MASKED;
         else {
+                u->load_state = UNIT_LOADED;
+
                 /* Now, parse the file contents */
                 r = config_parse(u->id, filename, f, UNIT_VTABLE(u)->sections,
                                  config_item_perf_lookup,
                                  (void*) load_fragment_gperf_lookup, false, true, u);
                 if (r < 0)
                         goto finish;
-
-                u->load_state = UNIT_LOADED;
         }
 
         free(u->fragment_path);