source files. Add a dependency rule for ctype_o to note
changes in ctype_iso.h and ctype_cp.h.
* libc/ctype/Makefile.in: Regenerate.
* libc/ctype/_tolower.c: Remove file.
* libc/ctype/_toupper.c: Remove file.
* libc/ctype/ctype_.c: Make sure ALLOW_NEGATIVE_CTYPE_INDEX
is always defined on Cygwin.
(_ctype_b): Don't make `static const' on Cygwin.
(ctype_iso.h): Include if _MB_EXTENDED_CHARSETS_ISO is set.
(ctype_cp.h): Include if _MB_EXTENDED_CHARSETS_WINDOWS is set.
(__ctype_ptr): Drop definition.
(__ctype_ptr__): De-constify. Mark as __EXPORT symbol.
(_ctype_): Add Cygwin-specifc asm define.
(__set_ctype): New function to set __ctype_ptr__ according to
current charset.
* libc/ctype/ctype_cp.h: New file containing Windows codepage
specific character class tables.
* libc/ctype/ctype_iso.h: New file containing ISO-8859-x
specific character class tables.
* libc/ctype/tolower.c (tolower): Reimplement to support any singlebyte
charset if one of the extended charsets is enabled.
* libc/ctype/toupper.c (toupper): Ditto.
* libc/include/ctype.h (_tolower): Define as macro per POSIX.
(_toupper): Ditto.
(__ctype_ptr__): De-constify.
(toupper): Disable macro on systems supporting extended charsets.
(tolower): Ditto.
* libc/include/sys/config.h (__EXPORT): Define empty if not defined.
* libc/locale/locale.c (__mb_cur_max): Mark as __EXPORT symbol.
(__set_ctype): Declare unconditionally.
(loadlocale): Remove __CYGWIN__ guard around __set_ctype call.
