| xf.li | bdd93d5 | 2023-05-12 07:10:14 -0700 | [diff] [blame^] | 1 | /* uselocale -- fetch and set the current per-thread locale |
| 2 | Copyright (C) 2002-2016 Free Software Foundation, Inc. |
| 3 | This file is part of the GNU C Library. |
| 4 | |
| 5 | The GNU C Library is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2.1 of the License, or (at your option) any later version. |
| 9 | |
| 10 | The GNU C Library is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with the GNU C Library; if not, see |
| 17 | <http://www.gnu.org/licenses/>. */ |
| 18 | |
| 19 | #include <locale.h> |
| 20 | #include "localeinfo.h" |
| 21 | #include <ctype.h> |
| 22 | |
| 23 | /* Switch the current thread's locale to DATASET. |
| 24 | If DATASET is null, instead just return the current setting. |
| 25 | The special value LC_GLOBAL_LOCALE is the initial setting |
| 26 | for all threads, and means the thread uses the global |
| 27 | setting controlled by `setlocale'. */ |
| 28 | locale_t |
| 29 | __uselocale (locale_t newloc) |
| 30 | { |
| 31 | locale_t oldloc = _NL_CURRENT_LOCALE; |
| 32 | |
| 33 | if (newloc != NULL) |
| 34 | { |
| 35 | const locale_t locobj |
| 36 | = newloc == LC_GLOBAL_LOCALE ? &_nl_global_locale : newloc; |
| 37 | __libc_tsd_set (__locale_t, LOCALE, locobj); |
| 38 | |
| 39 | #ifdef NL_CURRENT_INDIRECT |
| 40 | /* Now we must update all the per-category thread-local variables to |
| 41 | point into the new current locale for this thread. The magic |
| 42 | symbols _nl_current_LC_FOO_used are defined to meaningless values |
| 43 | if _nl_current_LC_FOO was linked in. By using weak references to |
| 44 | both symbols and testing the address of _nl_current_LC_FOO_used, |
| 45 | we can avoid accessing the _nl_current_LC_FOO thread-local |
| 46 | variable at all when no code referring to it was linked in. We |
| 47 | need the special bogus symbol because while TLS symbols can be |
| 48 | weak, there is no reasonable way to test for the default-zero |
| 49 | value as with a heap symbol (taking the address would just use |
| 50 | some bogus offset from our thread pointer). */ |
| 51 | |
| 52 | # define DEFINE_CATEGORY(category, category_name, items, a) \ |
| 53 | { \ |
| 54 | extern char _nl_current_##category##_used; \ |
| 55 | weak_extern (_nl_current_##category##_used) \ |
| 56 | weak_extern (_nl_current_##category) \ |
| 57 | if (&_nl_current_##category##_used != 0) \ |
| 58 | _nl_current_##category = &locobj->__locales[category]; \ |
| 59 | } |
| 60 | # include "categories.def" |
| 61 | # undef DEFINE_CATEGORY |
| 62 | #endif |
| 63 | |
| 64 | /* Update the special tsd cache of some locale data. */ |
| 65 | __libc_tsd_set (const uint16_t *, CTYPE_B, (void *) locobj->__ctype_b); |
| 66 | __libc_tsd_set (const int32_t *, CTYPE_TOLOWER, |
| 67 | (void *) locobj->__ctype_tolower); |
| 68 | __libc_tsd_set (const int32_t *, CTYPE_TOUPPER, |
| 69 | (void *) locobj->__ctype_toupper); |
| 70 | } |
| 71 | |
| 72 | return oldloc == &_nl_global_locale ? LC_GLOBAL_LOCALE : oldloc; |
| 73 | } |
| 74 | libc_hidden_def (__uselocale) |
| 75 | weak_alias (__uselocale, uselocale) |