Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

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

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

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

Compile contrib/tzcode/stdtime/localtime.c with -fwrapv, since it relies
on signed integer overflow wrapping. Otherwise mktime(3) and timegm(3)
can hang, in case the timestamp passed in struct tm is not representable
in a time_t. Specifically, any timestamp after 2038-01-19 03:14:07, in
combination with a 32-bit time_t.

Note that it would be better to change the code to not rely on undefined
behaviour, but it is contributed code, and it is not entirely trivial to
fix the issue properly.

MFC after: 3 days

Add more locale-specific functions to the relevant man pages and
Makefiles:
- libc/stdtime/strftime.3
- libc/stdtime/strptime.3
- libc/stdlib/strfmon.3

Reviewed by: theraven
Approved by: gabor (mentor)

Split the contributed code from libc/stdtime from lib/libc/stdtime
to contrib/tzcode/stdtime.

Add each directory's symbol map file to SYM_MAPS.

libc_r wasn't so tied to libc for 22 months.

Add routines to convert time_t to/from fixed-bit fields. These routines
serve two purposes: (1) so we can maintain backwards compatibility with
protocols (rwhod, dump, etc...) that either assume time_t is 32 bits or
assume sizeof(time_t) == sizeof(int), or make other similar assumptions.
(2) To tag such routines (by the presence of these calls) for future
cleanup/extension work.

The 32->64 routine, time32_to_time() (when time_t is 64 bits, that is),
is defined specifically to implement temporal locality to properly set the
msb bits of a 64 bit time_t quantity, using the 50 year rule. The locality
code has not been implemented yet (and doesn't need to be for a while),
but that is the intent. This will allow us to maintain backwards protocol
compatibility past 2038.

These routines are intended to be platform and time_t agnostic.

MFC after: 1 week

MAN[1-9] -> MAN.

Rewrite __time_load_locale() using ldpart.c::__part_load_locale()

Reviewed by: ache

Create the links for the reentrant time functions.

PR: docs/22644
Submitted by: andrew@ugh.net.au

$Id$ -> $FreeBSD$

Describe timegm()

Sorted lists.

Removed the subdirectory paths from the definitions of MAN[1-9]. They
were a workaround for limitations in bsd.man.mk that were fixed about
2 years ago.

Import strptime(3) into libc. We've got permission by Kevin Ruddy to
modify the original `no modifications' copyright message, and i've
included his mail into the source file.

The common localization functions between strptime(3) and strftime(3)
have been broken out into timelocal.[ch].

Changed all paths to be relative to src/lib instead of src/lib/libc
so that all these makefiles can be used to build libc_r too.

Added .if ${LIB} == "c" tests to restrict man page builds to libc
to avoid needlessly building them with libc_r too.

Split libc Makefile into Makefile and Makefile.inc to allow the
libc_r Makefile to include Makefile.inc too.

Add some missing manual page links.

Use latest Arthur Olson timezone code rather than that supplied with
4.4. The code is almost identical to the 4.4 versions, but this organization
should make it easier to merge new versions in the future.

Port to FreeBSD. Not ready for inclusion in libc just yet, but here
so we can compile zic.