By default, Newlib uses a huge object of type struct _reent to store
thread-specific data. This object is returned by __getreent() if the
__DYNAMIC_REENT__ Newlib configuration option is defined.
The reentrancy structure contains for example errno and the standard input,
output, and error file streams. This means that if an application only uses
errno it has a dependency on the file stream support even if it does not use
it. This is an issue for lower end targets and applications which need to
qualify the software according to safety standards (for example ECSS-E-ST-40C,
ECSS-Q-ST-80C, IEC 61508, ISO 26262, DO-178, DO-330, DO-333).
If the new _REENT_THREAD_LOCAL configuration option is enabled, then struct
_reent is replaced by dedicated thread-local objects for each struct _reent
member. The thread-local objects are defined in translation units which use
the corresponding object.
Add a _REENT_ERRNO() macro to encapsulate the access to the
_errno member of struct reent. This will help to replace the
structure member with a thread-local storage object in a follow
up patch.
Replace uses of __errno_r() with _REENT_ERRNO(). Keep __errno_r() macro for
potential users outside of Newlib.
- Remove charset parameter from low level __foo_wctomb/__foo_mbtowc calls.
- Instead, create array of function for ISO and Windows codepages to point
to function which does not require to evaluate the charset string on
each call. Create matching helper functions. I.e., __iso_wctomb,
__iso_mbtowc, __cp_wctomb and __cp_mbtowc are functions returning the
right function pointer now.
- Create __WCTOMB/__MBTOWC macros utilizing per-reent locale and replace
calls to __wctomb/__mbtowc with calls to __WCTOMB/__MBTOWC.
- Drop global __wctomb/__mbtowc vars.
- Utilize aforementioned changes in Cygwin to get rid of charset in other,
calling functions and simplify the code.
- In Cygwin restrict global cygheap locale info to the job performed
by internal_setlocale. Use UTF-8 instead of ASCII on the fly in
internal conversion functions.
- In Cygwin dll_entry, make sure to initialize a TLS area with a NULL
_REENT->_locale pointer. Add comment to explain why.
Signed-off by: Corinna Vinschen <corinna@vinschen.de>
_mbtowc_r with direct call to __mbtowc.
* libc/stdio/vfscanf.c: Ditto.
* libc/stdlib/btowc.c: Include local.h. Replace call to _mbtowc_r
with direct call to __mbtowc.
* libc/stdlib/mblen.c: Ditto.
* libc/stdlib/mblen_r.c: Ditto.
* libc/stdlib/mbrtowc.c: Ditto.
* libc/stdlib/mbstowcs_r.c: Ditto.
* libc/stdlib/mbtowc.c: Ditto.
* libc/stdlib/wcrtomb.c: Include local.h. Replace call to _wctomb_r
with direct call to __wctomb.
* libc/stdlib/wcsnrtombs.c: Ditto.
(_wcsnrtombs_r): Ditto.
* libc/stdlib/wcstombs_r.c: Ditto.
* libc/stdlib/wctob.c: Ditto.
* libc/stdlib/wctomb.c: Ditto.
* libc/stdlib/mbrtowc.c (mbrtowc): Implement independently from
_mbrtowc_r, unless PREFER_SIZE_OVER_SPEED or __OPTIMIZE_SIZE__ are
defined.
* libc/stdlib/wcrtomb.c (wcrtomb): Implement independently from
_wcrtomb_r, unless PREFER_SIZE_OVER_SPEED or __OPTIMIZE_SIZE__ are
defined.
* libc/stdlib/mbtowc_r.c (__utf8_mbtowc): Drop unnecessary test for
ch >= 0.
Matt Joyce
Yaakov Selkowitz
Corinna Vinschen
Jon TURNEY
Joel Sherrill