MFC r326276:

various: general adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.

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

Sync apmd(8) with DragonflyBSD, bringing WARNS to 3

Reviewed by: ed (partial, long time ago)

de-__P()

Add battery state monitoring to apmd.

The new syntax available in the config file is:

apm_battery [0-9]+(%|[Mm) (dis|)charging { ... }

The stuff in the braces is the same as the existing case. nn% checks for
a certain percentage of life remaining and nnM checks for a cerain
number of minutes remaining. Specifying "discharge" means that you're
interested in knowing when the battery reaches a certain level while AC
power is off, "charging" the opposite.

The man page needs to be updated.

The code can be fooled. If you SIGHUP the daemon and the battery level
matches a rule it will be performed once per SIGHUP. If the battery
level matches a rule and you repeatedly apply and take away AC power,
the rule will be run once per occurance. This, however, is a feature.
:-) The code also only runs when select() times out, so getting APM
events more often than the timeout interval will result in the rules not
being run. These are things that remain to be overcome.

$Id$ -> $FreeBSD$

This commit was generated by cvs2svn to compensate for changes in r48730,
which included commits to RCS files with non-trunk default branches.

The apmd package provides a means of handling various APM events from
userland code. Using apmd.conf, the apmd(8) configuration file, you
can select the APM events to be handled from userland and specify the
commands for a given event, allowing APM behaviour to be configured
flexibly.

Have Fun!

Submitted by: iwasaki, KOIE Hidetaka <hide@koie.org>
Reviewed by: -hackers, -mobile and bsd-nomads ML folks.
Contributed by: Warner Losh <imp@FreeBSD.org>,
Hiroshi Yamashita <bluemoon@msj.biglobe.ne.jp>,
Yoshihiko SARUMARU <mistral@imasy.or.jp>,
Norihiro Kumagai <kuma@nk.rim.or.jp>,
NAKAGAWA Yoshihisa <nakagawa@jp.FreeBSD.org>, and
Nick Hilliard <nick@foobar.org>.