Remove $FreeBSD$: one-line .h pattern

Remove /^\s*\*+\s*\$FreeBSD\$.*$\n/

Vendor import of stripped libc++ trunk r366426 (just before the release_90 branch
point):

https://llvm.org/svn/llvm-project/libcxx/trunk@366426

include: General further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified 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.

Vendor import of libc++ trunk r256633:
https://llvm.org/svn/llvm-project/libcxx/trunk@256633

Commit log from Dragonfly:

FreeBSD extended ctypes to include numbers (e.g. isnumber()) but never
actually implemented it. The isnumber() function was equivalent to the
isdigit() function in every case.

Now that DragonFly's ctype source files have number definitions, the
number ctype can finally be implemented. It's given a new flag _CTYPE_N.
The isalnum() and iswalnum() functions have been changed to use this
flag rather than the _CTYPE_D digit flag.

While isalnum(), isnumber(), and their wide equivalents now return
different values in locale cases, the ishexnumber() and iswhexnumber()
functions are unchanged. They are still aliases for isxdigit() and
iswxdigit().

Also change ctype.h for isdigit and isxdigit to use sbistype like the
other functions.

Obtained from: dragonfly

Reapply 227753 (xlocale cleanup), plus some fixes so that it passes build
universe with gcc.

Approved by: dim (mentor)

Revert r231673 and r231682 for now, until we can run a full make
universe with them. Sorry for the breakage.

Pointy hat to: me and brooks

Cleanup of xlocale:

- Address performance regressions encountered by das@ by caching per-thread
data in TLS where available.
- Add a __NO_TLS flag to cdefs.h to indicate where not available.
- Reorganise the xlocale.h definitions into xlocale/*.h so that they can be
included from multiple places.
- Export the POSIX2008 subset of xlocale when POSIX2008 says it should be
exported, independently of whether xlocale.h is included.
- Fix the bug where programs using ctype functions always assumed ASCII unless
recompiled.
- Fix some style(9) violations.

Reviewed by: brooks (mentor)
Approved by: dim (mentor)

Don't expose the wctype.h macros in C++ mode. They cause problems when
people try to invoke the namespaced versions of the functions of the
same names.

Approved by: dim (mentor)

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Create the altix project branch. The altix project will add support
for the SGI Altix 350 to FreeBSD/ia64. The hardware used for porting
is a two-module system, consisting of a base compute module and a
CPU expansion module. SGI's NUMAFlex architecture can be an excellent
platform to test CPU affinity and NUMA-aware features in FreeBSD.

- Import the HEAD csup code which is the basis for the cvsmode work.

Back out iswascii change from prev. commit, iswascii was right,
some overlook from me.

The problem is: currently our single byte ctype(3) functions are broken
for wide characters locales in the argument range >= 0x80 - they may
return false positives.

Example 1: for UTF-8 locale we currently have:
iswspace(0xA0)==1 and isspace(0xA0)==1
(because iswspace() and isspace() are the same code)
but must have
iswspace(0xA0)==1 and isspace(0xA0)==0
(because there is no such character and all others in the range
0x80..0xff for the UTF-8 locale, it keeps ASCII only in the single byte
range because our internal wchar_t representation for UTF-8 is UCS-4).

Example 2: for all wide character locales isalpha(arg) when arg > 0xFF may
return false positives (must be 0).
(because iswalpha() and isalpha() are the same code)

This change address this issue separating single byte and wide ctype
and also fix iswascii() (currently iswascii() is broken for
arguments > 0xFF).
This change is 100% binary compatible with old binaries.

Reviewied by: i18n@

Include _ctype.h instead of ctype.h to avoid namespace pollution.

Add a function to iterate over all characters in a particular character
class. This is necessary in order to implement tr(1) efficiently in
multibyte locales, since the brute force method of finding all characters
in a class is infeasible with a 32-bit (or wider) wchar_t.

Use __isctype() instead of __istype() for iswdigit() and iswxdigit() for
consistency with <ctype.h>.

o Merge <machine/ansi.h> and <machine/types.h> into a new header
called <machine/_types.h>.
o <machine/ansi.h> will continue to live so it can define MD clock
macros, which are only MD because of gratuitous differences between
architectures.
o Change all headers to make use of this. This mainly involves
changing:
#ifdef _BSD_FOO_T_
typedef _BSD_FOO_T_ foo_t;
#undef _BSD_FOO_T_
#endif
to:
#ifndef _FOO_T_DECLARED
typedef __foo_t foo_t;
#define _FOO_T_DECLARED
#endif

Concept by: bde
Reviewed by: jake, obrien

Whitespace formatting changes: line up macro bodies, function names,
place tabs after #define and typedef. Sort typedefs by name.

Requested by: mike

Implement the missing <wctype.h> functions: isw*() (iswalnum() etc.),
towlower() and towupper() required by ISO C90 Amd. 1.

iswascii(), iswhexnumber(), iswideogram(), iswnumber(), iswphonogram(),
iswrune() and iswspecial() have also been implemented for consistency
with the BSD extensions in <ctype.h>.

Change wctype_t to an unsigned type to avoid warnings.

Add the ISO C90 Amd. 1 wctrans(3) and towctrans(3) functions.

Add ISO C90 Amd. 1 wctype(3) and iswctype(3) functions.

Breath deep and take __P out of the system include files.

# This appears to not break X11, but I'm having problems compiling the
# glide part of the server with or without this patch, so I can't tell
# for sure.

VCS ID fixup

adapt to FreeBSD.
- add #define NULL 0 instead of sys/null.h.
- enable locale-insensitive functions:
wcscat.c wcschr.c wcscmp.c wcscpy.c wcscspn.c wcslcat.c wcslcpy.c
wcslen.c wcsncat.c wcsncmp.c wcsncpy.c wcspbrk.c wcsrchr.c wcsspn.c
wcsstr.c wmemchr.c wmemcmp.c wmemcpy.c wmemmove.c wmemset.c
- disable some locale-sensitive functions defined in wchar.h temporarily:
mbrlen mbrtowc mbsinit mbsrtowcs wcrtomb wcsrtombs wcwidth wcswidth
- disable all functions defined in wctype.h temporarily:
is* tow*

initial import of wchar.h and wctype.h

Obtained from: NetBSD and Citrus XPG4DL