SIGTERM should be considered a clean exit code for daemons (i.e. long-running
processes, as a daemon without SIGTERM handler may be shut down without issues
via SIGTERM still) while it should not be considered a clean exit code for
commands (i.e. short-running processes).
Let's add two different clean checking modes for this, and use the right one at
the appropriate places.
Fixes: #4275
Let's get rid of is_clean_exit_lsb(), let's move the logic for the special
handling of the two LSB exit codes into the sysv-generator by writing out
appropriate SuccessExitStatus= lines if the LSB header exists. This is not only
semantically more correct, bug also fixes a bug as the code in service.c that
chose between is_clean_exit_lsb() and is_clean_exit() based this check on
whether a native unit files was available for the unit. However, that check was
bogus since a long time, since the SysV generator was introduced and native
SysV script support was removed from PID 1, as in that case a unit file always
existed.
Do not make up our own type for ExitStatus, but use the type used by POSIX for
this, which is "int". In particular as we never used that type outside of the
definition of exit_status_to_string() where we internally cast the paramter to
(int) every single time we used it.
Hence, let's simplify things, drop the type and use the kernel type directly.
Lennart Poettering
Daniel Mack
Thomas Hindoe Paaboel Andersen
Sungbae Yoo
Michael Olbrich
Kay Sievers