reactos/sdk/lib/ucrt/locale/setlocale.cpp
2025-01-16 14:18:53 +02:00

118 lines
4.4 KiB
C++

/***
*setlocal.c - Contains the setlocale function
*
* Copyright (c) Microsoft Corporation. All rights reserved.
*
*Purpose:
* Contains the _wsetlocale() function.
*
*******************************************************************************/
#include <corecrt_internal.h>
#include <locale.h>
#include <stdlib.h>
static wchar_t* __cdecl call_wsetlocale(int const category, char const* const narrow_locale)
{
if (narrow_locale == nullptr)
return _wsetlocale(category, nullptr);
size_t size;
_ERRCHECK_EINVAL_ERANGE(mbstowcs_s(&size, nullptr, 0, narrow_locale, INT_MAX));
__crt_unique_heap_ptr<wchar_t> wide_locale(_calloc_crt_t(wchar_t, size));
if (wide_locale.get() == nullptr)
return nullptr;
if (_ERRCHECK_EINVAL_ERANGE(mbstowcs_s(nullptr, wide_locale.get(), size, narrow_locale, _TRUNCATE)) != 0)
return nullptr;
return _wsetlocale(category, wide_locale.get());
}
extern "C" char* __cdecl setlocale(int _category, char const* _locale)
{
// Deadlock Avoidance: See the comment in _wsetlocale on usage of this function.
__acrt_eagerly_load_locale_apis();
return __acrt_lock_and_call(__acrt_locale_lock, [&]() -> char*
{
// Convert ASCII string into a wide character string:
wchar_t* const outwlocale = call_wsetlocale(_category, _locale);
if (outwlocale == nullptr)
{
return nullptr;
}
__acrt_ptd* const ptd = __acrt_getptd();
__crt_locale_pointers locale;
locale.locinfo = ptd->_locale_info;
locale.mbcinfo = ptd->_multibyte_info;
// We now have a locale string, but the global locale can be changed by
// another thread. If we allow this thread's locale to be updated before
// we're done with this string, it might be freed from under us. We call
// the versions of the wide-to-multibyte conversions that do not update the
// current thread's locale.
size_t size = 0;
if (_ERRCHECK_EINVAL_ERANGE(_wcstombs_s_l(&size, nullptr, 0, outwlocale, 0, &locale)) != 0)
{
return nullptr;
}
long* const refcount = static_cast<long*>(_malloc_crt(size + sizeof(long)));
if (refcount == nullptr)
{
return nullptr;
}
char* outlocale = reinterpret_cast<char*>(&refcount[1]);
/* convert return value to ASCII */
if (_ERRCHECK_EINVAL_ERANGE(_wcstombs_s_l(nullptr, outlocale, size, outwlocale, _TRUNCATE, &locale)) != 0)
{
_free_crt(refcount);
return nullptr;
}
__crt_locale_data* ptloci = locale.locinfo;
_ASSERTE((ptloci->lc_category[_category].locale != nullptr && ptloci->lc_category[_category].refcount != nullptr) ||
(ptloci->lc_category[_category].locale == nullptr && ptloci->lc_category[_category].refcount == nullptr));
if (ptloci->lc_category[_category].refcount != nullptr &&
_InterlockedDecrement(ptloci->lc_category[_category].refcount) == 0)
{
_free_crt(ptloci->lc_category[_category].refcount);
ptloci->lc_category[_category].refcount = nullptr;
}
if (__acrt_should_sync_with_global_locale(ptd))
{
if (ptloci->lc_category[_category].refcount != nullptr &&
_InterlockedDecrement(ptloci->lc_category[_category].refcount) == 0)
{
_free_crt(ptloci->lc_category[_category].refcount);
ptloci->lc_category[_category].refcount = nullptr;
}
}
/*
* Note that we are using a risky trick here. We are adding this
* locale to an existing __crt_locale_data struct, and thus starting
* the locale's refcount with the same value as the whole struct.
* That means all code which modifies both __crt_locale_data::refcount
* and __crt_locale_data::lc_category[]::refcount in structs that are
* potentially shared across threads must make those modifications
* under the locale lock. Otherwise, there's a race condition
* for some other thread modifying __crt_locale_data::refcount after
* we load it but before we store it to refcount.
*/
*refcount = ptloci->refcount;
ptloci->lc_category[_category].refcount = refcount;
ptloci->lc_category[_category].locale = outlocale;
return outlocale;
});
}