Fixes to 8-bit character handling

[Hallvard B Furuseth <h.b.furuseth@usit.uio.no>]

devel-980915 patch in <URL:http://www.uio.no/~hbf/openldap-0916.diff>:

Page 1:  Various fixes:

  liblutil/lutil_sha1.h	uses __P, but nobody defines it.
  liblutil/sha1.c	O_RDONLY was not defined.
			(I don't know how portable this patch is.)
  ldapd/main.c		Pointer-type error.

Page 2:  Fix handling of 8-bit characters (gcc -Wchar-subscripts):

  isXXX(ch) -> isXXX((unsigned char)ch) for ctype.h functions,
  because their domain is (EOF, 0 - UCHAR_MAX).
  Only modified if ch is a char, not if it's an int (which can be -1).

  I've probably "fixed" a number of instances that wil never happen,
  but that was easier than to look closely at each item and decide if
  the character can be 8-bit.

  Also changed a few non-pointer NULLs to 0 or '\0'.

Page 3:  Just some `gcc -Wcomment' cleanup, while I'm patching anyway.


BTW, how should I send/install patches like this?
I suspect something about CVS is the clue, but I don't know how.


PS:

openldap-devel.tgz points to
	openldap-devel/openldap-stable-980915.tgz
instead of
	openldap-devel/openldap-devel-980915.tgz

-- 
Hallvard