| /* uselocale -- fetch and set the current per-thread locale |
| Copyright (C) 2002-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <locale.h> |
| #include "localeinfo.h" |
| #include <ctype.h> |
| |
| /* Switch the current thread's locale to DATASET. |
| If DATASET is null, instead just return the current setting. |
| The special value LC_GLOBAL_LOCALE is the initial setting |
| for all threads, and means the thread uses the global |
| setting controlled by `setlocale'. */ |
| locale_t |
| __uselocale (locale_t newloc) |
| { |
| locale_t oldloc = _NL_CURRENT_LOCALE; |
| |
| if (newloc != NULL) |
| { |
| const locale_t locobj |
| = newloc == LC_GLOBAL_LOCALE ? &_nl_global_locale : newloc; |
| __libc_tsd_set (locale_t, LOCALE, locobj); |
| |
| #ifdef NL_CURRENT_INDIRECT |
| /* Now we must update all the per-category thread-local variables to |
| point into the new current locale for this thread. The magic |
| symbols _nl_current_LC_FOO_used are defined to meaningless values |
| if _nl_current_LC_FOO was linked in. By using weak references to |
| both symbols and testing the address of _nl_current_LC_FOO_used, |
| we can avoid accessing the _nl_current_LC_FOO thread-local |
| variable at all when no code referring to it was linked in. We |
| need the special bogus symbol because while TLS symbols can be |
| weak, there is no reasonable way to test for the default-zero |
| value as with a heap symbol (taking the address would just use |
| some bogus offset from our thread pointer). */ |
| |
| # define DEFINE_CATEGORY(category, category_name, items, a) \ |
| { \ |
| extern char _nl_current_##category##_used; \ |
| weak_extern (_nl_current_##category##_used) \ |
| weak_extern (_nl_current_##category) \ |
| if (&_nl_current_##category##_used != 0) \ |
| _nl_current_##category = &locobj->__locales[category]; \ |
| } |
| # include "categories.def" |
| # undef DEFINE_CATEGORY |
| #endif |
| |
| /* Update the special tsd cache of some locale data. */ |
| __libc_tsd_set (const uint16_t *, CTYPE_B, (void *) locobj->__ctype_b); |
| __libc_tsd_set (const int32_t *, CTYPE_TOLOWER, |
| (void *) locobj->__ctype_tolower); |
| __libc_tsd_set (const int32_t *, CTYPE_TOUPPER, |
| (void *) locobj->__ctype_toupper); |
| } |
| |
| return oldloc == &_nl_global_locale ? LC_GLOBAL_LOCALE : oldloc; |
| } |
| libc_hidden_def (__uselocale) |
| weak_alias (__uselocale, uselocale) |
