Joachim Wiberg
6b03a1ec8f
Aaron Andersen points out in the #492 discussion that the *Directory settings carry more contract than create-and-chown: per-directory modes, specific ownership rules, and cleanup toggles. Without them config-dir was chowned to the service user, which systemd never does, an existing directory with drifted ownership was left wrong, and the runtime directory could not survive a restart. Now matching systemd.exec(5), and where the man page is vague, the code in setup_exec_directory(): - each directory takes a matching -mode key, octal with the leading zero, default 0755. The mode of the named directory is locked down again on every start, also when it already exists - config-dir is created but never chowned - the contents of an existing directory are left alone as long as the owner is right; on drift everything under it is chowned back - runtime-dir-preserve = no | restart | yes maps RuntimeDirectoryPreserve=. A service still qualified to run when the runtime directory would be removed is restarting, not stopping, which is what svc_enabled() answers The dir mechanics move to mksubsysd(), taking resolved ids, with mksubsys() reduced to a name-resolving wrapper for the dbus plugin. The child resolves uid/gid once for both directory setup and privilege drop. The symlink form, RuntimeDirectory=foo:bar, is not adopted. Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
This section provides an overview of Finit's configuration system. For detailed information on specific topics, see the individual sections in the navigation menu.
Configuration File Syntax
A .conf file is a series of blocks. Every setting is a key inside
one, so nothing has to be remembered by position:
service sysklogd {
description = "System log daemon"
runlevel = "S123456789"
envfile = "-/etc/default/sysklogd"
command = "syslogd -F $SYSLOGD_ARGS"
}
Values are quoted strings, bare words, or integers. Lists use braces, and a block may carry a title, which becomes the service identity:
# shell comment
// C++ comment
/* C comment */
key = "value" # string
number = 20 # integer
flag = true # boolean
list = { "one", "two" } # string list
block title { key = "value" } # titled section
path = "${HOME}/thing" # environment expansion
include("/etc/finit.d/extra.conf") # include another file
Bare words work wherever a string is expected, so memory.max = 65M
and restart = always need no quotes.
Two conventions
Keys are kebab-case, never snake_case or CamelCase: restart-sec,
stop-timeout, reboot-watchdog.
Keys that take a list are plural: conditions, conflicts,
capabilities, modules, extra-groups. Two imperatives keep their
singular form because they are verbs rather than nouns: mknod and
include.
Short forms
Nine keys have an alias. An alias may abbreviate the canonical name, or preserve the spelling the line-based format used; it never renames.
| Canonical | Alias | Canonical | Alias |
|---|---|---|---|
description |
desc |
manual-start |
manual |
conditions |
cond |
remain-after-exit |
remain |
capabilities |
caps |
stop-signal |
halt |
modules |
mod |
stop-timeout |
kill |
envfile |
env |
Optional paths
A leading - on a path means carry on if it is not there:
service foo {
envfile = "-/etc/default/foo" # skip the file if missing
command = "-/usr/sbin/foo" # skip the whole block if missing
}
That is the only mark meaning "optional". Two others mean something
else: ! on runlevel inverts the set, e.g. runlevel = "!12345",
and ~ on a condition propagates a reload from the service it names.
Both are covered where they apply.
Both Formats Are Read
Finit also reads the line-based format it has always used, where a stanza is a keyword followed by values whose meaning comes from their position:
service [S123456789] env:-/etc/default/sysklogd syslogd -F $SYSLOGD_ARGS -- System log daemon
That format still works and is not going away. It is frozen at the Finit 4.x feature set, so new settings appear only in the block format, and the documentation is written in blocks throughout.
There is no new file extension and no marker line. Every file is still
*.conf, and Finit decides which format a file is in by reading it: if
it parses as blocks it is a block file, otherwise it goes to the
line-based parser. A file is one format or the other, never a mix.
Because the two are told apart before either parser commits, a typo reports its own file and line instead of being mistaken for the other format:
parse error: /etc/finit.d/foo.conf:3: no such option 'commnad'
The .conf files /etc/finit.conf and /etc/finit.d/* support many
settings. Some are restricted, e.g., only available at bootstrap,
runlevel S. Read on in Files & Layout for more on how
to structure your .conf files.
For details on restrictions, see Limitations.