glibc/wcsmbs
Carlos O'Donell 61af4bbb2a mbstowcs: Document, test, and fix null pointer dst semantics (Bug 25219)
The function mbstowcs, by an XSI extension to POSIX, accepts a null
pointer for the destination wchar_t array.  This API behaviour allows
you to use the function to compute the length of the required wchar_t
array i.e. does the conversion without storing it and returns the
number of wide characters required.

We remove the __write_only__ markup for the first argument because it
is not true since the destination may be a null pointer, and so the
length argument may not apply.  We remove the markup otherwise the new
test case cannot be compiled with -Werror=nonnull.

We add a new test case for mbstowcs which exercises the destination is
a null pointer behaviour which we have now explicitly documented.

The mbsrtowcs and mbsnrtowcs behave similarly, and mbsrtowcs is
documented as doing this in C11, even if the standard doesn't come out
and call out this specific use case.  We add one note to each of
mbsrtowcs and mbsnrtowcs to call out that they support a null pointer
for the destination.

The wcsrtombs function behaves similarly but in the other way around
and allows you to use a null destination pointer to compute how many
bytes you would need to convert the wide character input.  We document
this particular case also, but leave wcsnrtombs as a references to
wcsrtombs, so the reader must still read the details of the semantics
for wcsrtombs.
2020-06-01 12:26:32 -04:00
..
bits Rename __LONG_DOUBLE_USES_FLOAT128 to __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI 2020-04-30 08:52:08 -05:00
btowc.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
c16rtomb.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
c32rtomb.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
Depend
isoc99_fwscanf.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
isoc99_swscanf.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
isoc99_vfwscanf.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
isoc99_vswscanf.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
isoc99_vwscanf.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
isoc99_wscanf.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
Makefile mbstowcs: Document, test, and fix null pointer dst semantics (Bug 25219) 2020-06-01 12:26:32 -04:00
mbrlen.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
mbrtoc16.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
mbrtoc32.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
mbrtowc.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
mbsinit.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
mbsnrtowcs.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
mbsrtowcs_l.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
mbsrtowcs.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
test-char-types.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
test-wcpcpy.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
test-wcpncpy.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
test-wcscat.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
test-wcschr.c
test-wcschrnul.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
test-wcscmp.c
test-wcscpy.c
test-wcscspn.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
test-wcslen.c
test-wcsncat.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
test-wcsncmp.c
test-wcsncpy.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
test-wcsnlen.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
test-wcspbrk.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
test-wcsrchr.c
test-wcsspn.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
test-wmemchr.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
test-wmemcmp.c
test-wmemset.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-btowc.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-c16-surrogate.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-c16c32-1.c
tst-c32-state.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-fgetwc-after-eof.c [BZ 1190] Make EOF sticky in stdio. 2018-03-13 08:31:56 -04:00
tst-mbrtowc2.c
tst-mbrtowc.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-mbsrtowcs.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-mbstowcs.c mbstowcs: Document, test, and fix null pointer dst semantics (Bug 25219) 2020-06-01 12:26:32 -04:00
tst-wchar-h.c
tst-wcpncpy.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-wcrtomb.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-wcsnlen.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-wcstod-nan-locale.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-wcstod-nan-sign.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-wcstod-round.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
tst-wcstof.c
tst-wcstol-locale.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
uchar.h Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
Versions Add _Float32 function aliases. 2017-12-07 00:48:31 +00:00
wchar.h Rename __LONG_DOUBLE_USES_FLOAT128 to __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI 2020-04-30 08:52:08 -05:00
wcpcpy.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcpncpy.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcrtomb.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsatcliff.c
wcscasecmp_l.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcscasecmp.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcscat.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcschr.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcschrnul.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcscmp.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcscoll_l.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcscoll.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcscpy.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcscspn.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsdup.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcslen.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsmbs-tst1.c
wcsmbsload.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsmbsload.h Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsncase_l.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsncase.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsncat.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsncmp.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsncpy.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsnlen.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsnrtombs.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcspbrk.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsrchr.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsrtombs.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsspn.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsstr.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstod_l.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstod_nan.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstod.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstof_l.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstof_nan.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstof.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstok.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstol_l.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstol.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstold_l.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstold_nan.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstold.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstoll_l.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstoll.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstoul_l.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstoul.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstoull_l.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcstoull.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcswidth.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsxfrm_l.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcsxfrm.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wctob.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcwidth.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wcwidth.h Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wmemchr.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wmemcmp.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wmemcpy.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wmemmove.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wmempcpy.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
wmemset.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00