More conservative umask

Set the file creation mask consistently because the files these scripts
create can become part of an iso image.

Deprecate extsrc/, EXTSRCSRCDIR, MKEXTSRC

Remove support for building extsrc/:
1. Makefile: remove do-extsrc target.
2. build.sh: remove options -y and -Y extsrcdir.
3. distrib/sets: remove support for extsrc in various tools
including the options -L ext and -y, and the extsrc sets.
4. doc/BUILDING.mdoc: remove docs for extsrc/, EXTSRCSRCDIR, MKEXTSRC (etc)
5. bsd.own.mk and various Makefiles: remove support for extsrc/,
EXTSRCSRCDIR, MKEXTSRC.

As proposed on tech-kern and tech-userlevel on 2022-01-07
and followed up on 2022-08-21.

Fix syntax error on OSX 10.5.
While here, simplify handling with OPTARG using IFS.

developped with and 'go for it' dsl@

Support "extsrc", externally added programs and libraries. Users can write
their own reach-overs, cross-build, install, and get set files just like base
and X11 / X.org. (These sets are not included as TNF releases.)

branches: 1.29.20;
No space in "function()", "command;" or "$(command)".
Requested by christos.

Add quotes to some shell variables overlooked in previous commit.

Ensure that (almost) all shell variables in distrib/sets/* scripts are
used with curly braces and quotes, as in "${var}".

Also ensure that command substitution is quoted, as in "$(command)", and
convert `command` to $(command).

Reviewed by agc

Add shell variables defined in sets.subr for almost all commands used
by scripts in distrib/sets/*. This is intended to be useful when cross
building. Only trivial commands like echo, cat, and rm are excluded
from this treatment.

While I am here, make ${MTREE} and ${DB} follow the pattern used by most
other such variables.

Reviewed by agc.

Don't remove empty obsolete lists; it unnecessarily complicates etc/Makefile

branches: 1.24.2;
Make all the sets scripts work even when not run from the directory that
they reside in.
Change any uses of dirname to use shell variable substitution instead.

rename all the <bsd.own.mk> derived variables to uppercase, and export
them to the environment.

Significant overhaul of how the sets are used:

* Add an optional third field to the sets file which is a list of
comma separated keywords that control if the line is printed.
Currently supported keywords
kerberos4 ${MKKERBEROS4} != no
kerberos ${MKKERBEROS} != no
lint ${MKLINT} != no
obsolete ${obsolete} != 0.
In this case, non obsolete files are not printed.
(This will allow future support for builds with variables such as
MKHESIOD and MKYP set to "no".)

* Use sh(1)'s getopts where appropriate, and otherwise cleanup the
various scripts.

* Move defaults for sets.subr from sets.defaults into sets.subr.
Move replicated code for determining stuff such as shlibs type
from various scripts into sets.subr.

* Merge the obsolete.*, krb.*, krb4.* and lint.* into the appropriate
main lists with the relevant third field keyword(s).

Redo creation of sets/sums so this can be parallelized if using -j.
Suggested in PR#20115 and PR#20116

Export use_tools_toolchain. Change last use of have_gcc3 to
use_tools_toolchain

Factor duplicated code for setting variables such as machine_cpu
and machine_arch to their defaults into sets.defaults, and source
it at the top of each script.

Also, to be consistent with variable naming, s/arch/machine_arch/.

sets.defaults introduces two new variables, krb and krb4, which
will affect whether Kerberos- or Kerberos IV-only files are put
into the set lists.

Fix sets handling so that GCC specific lists are really used.

etc/postinstall
* Improve message display in find_file_in_dirlist()
* do_obsolete(): instead of running distrib/sets/makeobsolete to
temporarily generate the obsolete sets lists, look for them in
${SRC_DIR}/etc/obsolete/* or ${DEST_DIR}/etc/obsolete/*.
The obsolete check now works for "extracted etc.tgz" as the source dir.

etc/Makefile (install-etc-files), distrib/sets/lists/*
* Install obsolete set lists into /etc/obsolete/
* Tweak how pwd_mkdb files are added to METALOG

distrib/sets/makeobsolete
* Don't bother with "_obsolete" suffix on generated file names.

use ${make} instead of ${MAKE} in the shell scripts, to prevent weird
lossage with the modified ${MAKE} getting passed to child make's

explicitly add " -f `dirname $0`/Makefile " to ${MAKE}, so that
these scripts do not need to be run from this directory in order
to function correctly

grammar fix

remove unnecessary code, and add minor code formatting tweak

use ${MAKE} print_machine(_arch)? where appropriate

set MAKE="${MAKE:-make} -j 1" to prevent problems where the output
of make -j N>1 would result in junk in various shell variables

branches: 1.10.2;
Adapt support for XFree86 3.3.6/4.x lists to match behaviour of
"makeflist".

Fix problem with building X11 release "tar" archives after support for
XFree86 4.x sets has been added. Problem noted by Richard Earnshaw in
private e-mail.

sh3e[bl] -> sh3.
sh3 has no shlib yet.

retire secr here, too.

Sort obsolete file lists in reverse order, so that subdirectories come
before their parent dirs. Avoids 'directory not empty' problems when
removing directories.

Obliterate "man/md_share". The difference is negligible relative to the
size of the man set, and with all architectures' man pages in "man", we
can now share both "man" and "misc" on all platforms (CD-ROM space saver).

Add the xmisc set.

Look for and use `obsolete.md_share'.

branches: 1.2.4;
Compatible upgrade to set list behavior -- any (whitespace separated) fields
after the first in each line of a set list are ignored. This introduces
no change in current set list behavior, but will need to be revisited if
we wish to distribute files with spaces in their names -- in this case we can
move to tab separated fields or some other behavior.

Current set lists work exactly as before, but in the future set lists may
have additional fields for use in a system packaging script.

I will post a detailed work plan for the system package system which uses
this to tech-pkg and tech-install in the next day or so.

branches: 1.1.2;
Generate the /dist/obsolete_* files used by sysinst from the obsolete lists
in sets/lists/*. The sript sets/makeobsolete concatenates the mi and md
obsolete list files all or a specified set and dumps it in a file, in a
subdir specified on the command line (inspired from the maketar and makeflist
files).
Use this for all the sysinst-based installs.
Untested for non-i386, and the md obsolete list may be wrong or incomplete.
Each postmaster is supposed to check this on his port.