This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
Since locale reading code not resistent against stack overflowing or
similar intruder attacks, don't allow PATH_LOCALE env variable action
for s-bit programs (non-standard locale path setting)
strdup() it to prevent unsetenv() or setenv() effects. Check its length to
not allow user to overflow internal locale buffer. Move PATH_LOCALE
handling code into one place.
POSIX: make better stub for LC_MONETARY & LC_NUMERIC, now it check
locale directory existance instead of refusing all non-C non-POSIX
locales. POSIX treats empty locale env variable as unset variable
while our old code treats it as "C" locale, fix it. Implement previous locale
restoring, if locale setting fails. Old code assumes success if some
of LC_ALL subset is successed even other fails, POSIX treats it as
failure with previous locale restoring, fix it.
Remove unneccessary length checking in currentlocale()
by me). This probably loses for multibyte characters, but I have no
way of telling. I'll let ache decide whether to add this support to
startup_setlocale. Note that for this to make any sense at all, the
symlinks in /usr/share/locale must go. (For the moment, this doesn't
make any difference since there are no locales supplied.)
Obtained from: Arthur David Olson <ado@elsie.nci.nih.gov>