syslogd(8) privileged and non-privileged parts now separate binaries

In OpenBSD, the syslogd(8) system logger has already for a while now fork(2)ed the privileged from the non-privileged parts.

Now Alexander Bluhm (bluhm@) decided it's time to split these parts into separate binaries in order to provide even better separation. The final commit message reads,

List:       openbsd-cvs
Subject:    CVS: cvs.openbsd.org: src
From:       Alexander Bluhm <bluhm () openbsd ! org>
Date:       2026-06-11 15:41:33

CVSROOT:	/cvs
Module name:	src
Changes by:	bluhm@cvs.openbsd.org	2026/06/11 09:41:33

Modified files:
	usr.sbin/syslogd: Makefile privsep.c syslogd.c syslogd.h 
	etc/rc.d       : syslogd 
Added files:
	usr.sbin/syslogd: Makefile.inc parent.c 
	usr.sbin/syslogd/parent: Makefile 
	usr.sbin/syslogd/syslogd: Makefile 

Log message:
Provide a separate executable file for syslogd parent.

syslogd(8) forks and execs its parent process to keep privileged
parts separated.  This parent process can be easily implemented as
a separate program.  It gets its own main() and minimal debug logging
functions.  The splitted parent process image is smaller, especially
without additional libs.
Use additional directories to build both parts.  The rcctl script
has to be adopted, as the parent process has a different name.

OK deraadt@

The code should be in snapshots by the time you read this. So please fire up that sysupgrade -s if you're already on snapshots!