This adds fozr new flags:
- If CONF_FILES_DIRECTORY is specified conf_file_list() and friends
will look for directories only.
- Similar CONF_FILES_REGULAR means we'll look only for regular files.
- If CONF_FILES_BASENAME is specified the resulting list will contain
only the basenames of all discovered files or directories, not the
full paths.
- If CONF_FILES_FILTER_MASKED is specified the resulting list will have
masked entries removed (i.e. those symlinked to /dev/null and
suchlike)
These four flags are useful for discovering portable service profile
information.
While we are at it, also improve a couple of other things:
- More debug logging
- use path_hash_ops instead of string_hash_ops when putting together the
path lists
Files which are installed as-is (any .service and other unit files, .conf
files, .policy files, etc), are left as is. My assumption is that SPDX
identifiers are not yet that well known, so it's better to retain the
extended header to avoid any doubt.
I also kept any copyright lines. We can probably remove them, but it'd nice to
obtain explicit acks from all involved authors before doing that.
This new flag will cause safe_fork() to wait for the forked off child
before returning. This allows us to unify a number of cases where we
immediately wait on the forked off child, witout running any code in the
parent after the fork, and without direct interest in the precise exit
status of the process, except recgonizing EXIT_SUCCESS vs everything
else.
This renames wait_for_terminate_and_warn() to
wait_for_terminate_and_check(), and adds a flags parameter, that
controls how much to log: there's one flag that means we log about
abnormal stuff, and another one that controls whether we log about
non-zero exit codes. Finally, there's a shortcut flag value for logging
in both cases, as that's what we usually use.
All callers are accordingly updated. At three occasions duplicate logging
is removed, i.e. where the old function was called but logged in the
caller, too.
This adds a new safe_fork() wrapper around fork() and makes use of it
everywhere. The new wrapper does a couple of things we previously did
manually and separately in a safer, more correct and automatic way:
1. Optionally resets signal handlers/mask in the child
2. Sets a name on all processes we fork off right after forking off (and
the patch assigns useful names for all processes we fork off now,
following a systematic naming scheme: always enclosed in () – in order
to indicate that these are not proper, exec()ed processes, but only
forked off children, and if the process is long-running with only our
own code, without execve()'ing something else, it gets am "sd-" prefix.)
3. Optionally closes all file descriptors in the child
4. Optionally sets a PR_SET_DEATHSIG to SIGTERM in the child, in a safe
way so that the parent dying before this happens being handled
safely.
5. Optionally reopens the logs
6. Optionally connects stdin/stdout/stderr to /dev/null
7. Debug logs about the forked off processes.
In the future we might want to allow additional syntax (for example
"unset VAR". But let's check that the data we're getting does not contain
anything unexpected.
The output of processes can be gathered, and passed back to the callee.
(This commit just implements the basic functionality and tests.)
After the preparation in previous commits, the change in functionality is
relatively simple. For coding convenience, alarm is prepared *before* any
children are executed, and not before. This shouldn't matter usually, since
just forking of the children should be pretty quick. One could also argue that
this is more correct, because we will also catch the case when (for whatever
reason), forking itself is slow.
Three callback functions and three levels of serialization are used:
- from individual generator processes to the generator forker
- from the forker back to the main process
- deserialization in the main process
v2:
- replace an structure with an indexed array of callbacks
Essentially the same logic as in conf_files_list() was independently implemented in
do_execute(). With previous commit, do_execute() can just call conf_files_list() to
get a list of executable paths.
