MFC: Fix calendar -a processing of files included in the user's home directory

The existing code performed a chdir() into the home directory, but the
parser fell back to using the invoking user's home directory as the base
directory for the search for an include file.

Since use of the -a option is limited to UID==0, the directory searched
was typically ~root/.calendar, not the .calendar directory of the user
whose file is being processed.

PR: 205580
Reported by: greg.bal4@gmail.com (Greg Balfour)
MFC after: 3 days

(cherry picked from commit 3fa2a149d68d22fa32ba7b6c09773388ac490fd1)

The code in -CURRENT is quite different (forks sub-processes tp
process the files for each user) but this change should provide the
same functionality as the referenced commit to -CURRENT.

Git Hash: f1031f07fb8b3994ffe14b5d780304e4de1f32fb
Git Author: se@FreeBSD.org

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

calendar(1): don't segfault in invalid input

When the user supplies an invalid number of days provide a useful error message
instead of segfaulting.

PR: bin/186697
Reported by: kaltheat <kaltheat@gmail.com>
Submitted by: oliver <oliver@beefrankly.org> (older version)

Revert revision 251648. style(9) requires an empty line here.

Reported by: mdf@

style(9)

MFC after: 2 weeks

More -Wmissing-variable-declarations fixes.

In addition to adding `static' where possible:

- bin/date: Move `retval' into extern.h to make it visible to date.c.
- bin/ed: Move globally used variables into ed.h.
- sbin/camcontrol: Move `verbose' into camcontrol.h and fix shadow warnings.
- usr.bin/calendar: Remove unneeded variables.
- usr.bin/chat: Make `line' local instead of global.
- usr.bin/elfdump: Comment out unneeded function.
- usr.bin/rlogin: Use _Noreturn instead of __dead2.
- usr.bin/tset: Pull `Ospeed' into extern.h.
- usr.sbin/mfiutil: Put global variables in mfiutil.h.
- usr.sbin/pkg: Remove unused `os_corres'.
- usr.sbin/quotaon, usr.sbin/repquota: Remove unused `qfname'.

Tidy up command line processing:
- Add ? option to optstring.
- Sort options alphabetically.
- Vertical space.

Tidy up usage() function.

Bring man page in sync with source.

Ensure that debug code is only executed with the -d option.

Submitted by: Christiane Yeardley

On request of joel@:

- Remove the 3rd clause of the UC Berkeley copyrighted files.
- For the files added copyrighted by me, move the "All rights
reserved" to the next line.

Long awaited update to the calendar system:

- Repeating events which span multiple years (because of -A, -B or
just the three days before the end of the year).

- Support for lunar events (full moon, new moon) and solar events
(equinox and solstice, chinese new year). Because of this, the
options -U (UTC offset) and -l (longitude) are available to
compensate if reality doesn't match the calculated values.

MFC after: 1 month

- Remove times.h from C programs that does not manipulate with time at
all.
- Remove pathnames.h from all but io.c since it's the only module that
used these definations.

Revert most part of 200420 as requested, as more review and polish is
needed.

Remove unneeded header includes from usr.bin/ except contributed code.

Tested with: make universe

Move functions which are only locally used into their C files and
make them static.

usage() in calendar.c
event_*() in io.c

PR: bin/118644
Approved by: bde@ (mentor)

style(9)ify usr.bin/calendar

PR: bin/118644
Approved by: bde@ (mentor)
MFC after: 1 week

ANSIfy function definitions.
Move some extern declarations to a header file.
Remove an unneeded extern declaration for optarg.

Fix the usage() to match style(9).

Add two new options:

-W is like -A (number of days in the future to consider, but also
specifies that we don't want special treatment at weekends.
-F changes our notion of "Friday" (the day before the weekend).

Arguably, calendar(1) is broken to have special treatment of weekends
by default, but this method maintains POLA.

Style improvements recommended by Bruce as a follow up to some
of the recent WARNS commits. The idea is:

1) FreeBSD id tags should follow vendor tags.
2) Vendor tags should not be compiled (though copyrights probably should).
3) There should be no blank line between including cdefs and __FBSDIF.

WARNS=2 fixup (mostly. Some are Hard To Fix(tm), so NO_WERROR is set)
Use __FBSDID().
Sort some headers.

Remove redundant declaration of optind. It has been declared in unistd.h
for ages.

List the -t option in usage().

PR: 21734
Submitted by: Giorgos Keramidas <keramida@ceid.upatras.gr>

Add missing $FreeBSD$ tags

Don't add '?' to getopt's options.

compare return value from getopt against -1 rather than EOF, per the final
posix standard on the topic.

Initialize the group list when we switch uids when run as
root with "calendar -a". Drop all privs when execing other
programs.

Obtained from: OpenBSD

Localize it
Handle Orthodox Eastern
-Wall cleanup

- handle events that move around from year to year, i.e.,
``the last Monday in April'
- handle easter

new options
-f calendarfile
-A days
-B days

Calendar HOME directory ~/.calendar
don't sent mail if ~/.calendar/nomail exist

Change error diagnostic to be less confusing:
no calendar file -> no calendar file in current directory

Remove hack inserted by me long time ago (cd $HOME for user-called case),
no other system do it and it can cause problem with multi-calendars
for single user.

Delete bogus referneces to timezone code internal header file `tzfile.h',
which is no longer bogusly installed in /usr/include.

Remove trailing whitespace.

Fix for two problems:
Calendar not cd $HOME when running by user
Calendar calls cpp with # lines allowed

This commit was generated by cvs2svn to compensate for changes in r1590,
which included commits to RCS files with non-trunk default branches.

BSD 4.4 Lite Usr.bin Sources