Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Use ANSI C prototypes. Eliminates -Wold-style-definition warnings.

Remove clause 3 and 4 from TNF licenses

Per the NetBSD Foundation statement
Third parties are encouraged to change the license on any files which
have a 4-clause license contributed to the NetBSD Foundation to a
2-clause license.

Add missing header needed by free()

Reported by: tinderbox

fix memory leak from reading nsswitch.conf

MFC after: 1 week

`cache' couldn't co-exist with `compat'.

Submitted by: "Michael Bushkov" <bushman__at__rsu.ru>

= Implement name service switch modules (NSS modules). NSS modules
may be built into libc (`static NSS modules') or dynamically loaded
via dlopen (`dynamic NSS modules'). Modules are loaded/initialized
at configuration time (i.e. when nsdispatch is called and nsswitch.conf
is read or re-read).

= Make the nsdispatch(3) core thread-safe.

= New status code for nsdispatch(3) `NS_RETURN', currently used to
signal ERANGE-type issues.

= syslog(3) problems, don't warn/err/abort.

= Try harder to avoid namespace pollution.

= Implement some shims to assist in porting NSS modules written for
the GNU C Library nsswitch interface.

Sponsored by: DARPA, Network Associates Laboratories

Remove __P() usage.

Don't ignore unknown characters. The previous code treated a line like:

hosts:!!!!!!!!@@@@@$%^&*()()*$(files{}{}|||++!)(dns

exactly the same as:

hosts: files dns

Recover from parse errors by looking for the end of a line; this
allows entries without errors to still be parsed even if there is
an erroneous entry earlier in the file.

Add nsswitch support. By creating an /etc/nsswitch.conf file, you can
configure FreeBSD so that various databases such as passwd and group can be
looked up using flat files, NIS, or Hesiod.

= Hesiod has been added to libc (see hesiod(3)).

= A library routine for parsing nsswitch.conf and invoking callback
functions as specified has been added to libc (see nsdispatch(3)).

= The following C library functions have been modified to use nsdispatch:
. getgrent, getgrnam, getgrgid
. getpwent, getpwnam, getpwuid
. getusershell
. getaddrinfo
. gethostbyname, gethostbyname2, gethostbyaddr
. getnetbyname, getnetbyaddr
. getipnodebyname, getipnodebyaddr, getnodebyname, getnodebyaddr

= host.conf has been removed from src/etc. rc.network has been modified
to warn that host.conf is no longer used at boot time. In addition, if
there is a host.conf but no nsswitch.conf, the latter is created at boot
time from the former.

Obtained from: NetBSD