* libc/include/sys/_types.h (_mbstate_t): Changed to use
unsigned char internally.
* libc/sys/linux/sys/_types.h: Ditto.
* libc/include/sys/reent.h
* libc/stdlib/mblen.c (mblen): Use function-specific state
value from default reentrancy structure.
* libc/stdlib/mblen_r.c (_mblen_r): If return code from
_mbtowc_r is less than 0, reset state __count value and
return -1.
* libc/stdlib/mbrlen.c (mbrlen): If the input state pointer
is NULL, use the function-specific pointer provided in the
default reentrancy structure.
* libc/stdlib/mbrtowc.c: Add reentrant form of function.
If input state pointer is NULL, use function-specific area
provided in reentrancy structure.
* libc/stdlib/mbsrtowcs.c: Ditto.
* libc/stdlib/wcrtomb.c: Ditto.
* libc/stdlib/wcsrtombs.c: Ditto.
* libc/stdlib/mbstowcs.c: Reformat.
* libc/stdlib/wcstombs.c: Ditto.
* libc/stdlib/mbstowcs_r.c (_mbstowcs_r): If an error occurs,
reset the state's __count value and return -1.
* libc/stdlib/mbtowc.c: Ditto.
* libc/stdlib/mbtowc_r.c (_mbtowc_r): Add restartable functionality.
If number of bytes is used up before completing a valid multibyte
character, return -2 and save the state.
* libc/stdlib/wctomb_r.c (_wctomb_r): Define __state as __count
and change some __count references to __state for clarity.
* libc/include/sys/reent.h (_REENT_INIT_PTR): New macro for
initializing a struct _reent that has been dynamically allocated.
(_REENT_CHECK_MISC): New macro that checks _misc struct for
_REENT_SMALL and does nothing otherwise.
(_REENT_STRTOK_LAST): New macro for reentrant strtok.
(_REENT_MBLEN_STATE): New macro for reentrant mblen.
(_REENT_MBTOWC_STATE): New macro for reentrant mbtowc.
(_REENT_WCTOMB_STATE): New macro for reentrant wctomb.
[_REENT_SMALL](struct _misc_reent): New structure containing
miscellaneous reentrant areas needed by newlib.
[_REENT_SMALL](struct _reent): Add _misc pointer.
[_REENT_SMALL](_REENT_INIT_MISC): New macro.
* libc/string/strtok (strtok): Change to use _REENT_CHECK_MISC
and _REENT_STRTOK_LAST macros.
* libc/stdlib/mblen (mblen): Change to use _REENT_CHECK_MISC
and _REENT_MBLEN_STATE macros.
* libc/stdlib/mbtowc (mbtowc): Change to use _REENT_CHECK_MISC
and _REENT_MBTOWC_STATE macros.
* libc/stdlib/wctomb (wctomb): Change to use _REENT_CHECK_MISC
and _REENT_WCTOMB_STATE macros.