Mostly on comments.

No need for the snprintf/asprintf dance; use fixed width formats.

Obtained from:	NetBSD (CVS rev. 1.8)
MFC after:	1 week

load of _l suffixed versions of various standard library functions that use
the global locale, making them take an explicit locale parameter.  Also
adds support for per-thread locales.  This work was funded by the FreeBSD
Foundation.

Please test any code you have that uses the C standard locale functions!

Reviewed by:    das (gdtoa changes)
Approved by:    dim (mentor)

http://www.freebsd.org/cgi/query-pr.cgi?pr=bin/143350
Empty string test gone wrong.

Testing this requires that you have a locale that has the sign string
unset but has int_n_sign_posn set (the default locale falls through to
use "()" around negative numbers which is probably another bug).

I created that setup by hand and indeed without this fix negative
numbers are put out as positive numbers (doesn't fall through to use
"-" as default indicator).

Unfixed example in nl_NL.ISO8859-1 with lc->negative_sign set to empty
string:
  strfmon(buf, sizeof(buf), "%-8i", -42.0);
==>
example2: 'EUR  42,00' 'Eu 42,00'

Fixed:
example2: 'EUR  42,00-' 'Eu 42,00-'

This file and suggested fix are identical in at least freebsd-8.
Backport might be appropriate but some expert on locales should
probably have a look at us defaulting to negative numbers in
parenthesis when LC_* is default.  That doesn't look right and is not
what other OSes are doing.

PR:		143350
Submitted by:	Corinna Vinschen
Reviewed by:	bug reporter submitted, tested by me

conversion specifiers for them are present.

Submitted by:	Maxim Dounin <mdounin@mdounin.ru>
Obtained from:	NetBSD (partially)
MFC after:	3 days

There were no checks for left and right precisions at all, and
a check for field width had integer overflow bug.

Reported by:	Maksymilian Arciemowicz
Security:	http://securityreason.com/achievement_securityalert/53
Submitted by:	Maxim Dounin <mdounin@mdounin.ru>
MFC after:	3 days

the function definition.