[UCRT] Import Microsoft.Windows.SDK.CRTSource version 10.0.22621.3

Imported from https://www.nuget.org/packages/Microsoft.Windows.SDK.CRTSource/10.0.22621.3
License: MIT

sdk/lib/ucrt/string/wcsnicmp.cpp

@@ -0,0 +1,132 @@
+/***
+*wcsnicmp.cpp - compare n chars of wide-character strings, ignoring case
+*
+*       Copyright (c) Microsoft Corporation. All rights reserved.
+*
+*Purpose:
+*       defines _wcsnicmp() - Compares at most n characters of two wchar_t
+*       strings, without regard to case.
+*
+*******************************************************************************/
+#include <corecrt_internal.h>
+#include <ctype.h>
+#include <corecrt_internal_securecrt.h>
+#include <locale.h>
+#include <string.h>
+
+/***
+*int _wcsnicmp(lhs, rhs, count) - compares count wchar_t of strings,
+*       ignore case
+*
+*Purpose:
+*       Compare the two strings for ordinal order.  Stops the comparison
+*       when the following occurs: (1) strings differ, (2) the end of the
+*       strings is reached, or (3) count characters have been compared.
+*       For the purposes of the comparison, upper case characters are
+*       converted to lower case (wide-characters).
+*
+*Entry:
+*       wchar_t *lhs, *rhs - strings to compare
+*       size_t count - maximum number of characters to compare
+*
+*Exit:
+*       Returns -1 if lhs < rhs
+*       Returns 0 if lhs == rhs
+*       Returns 1 if lhs > rhs
+*       Returns _NLSCMPERROR if something went wrong
+*       This range of return values may differ from other *cmp/*coll functions.
+*
+*Exceptions:
+*       Input parameters are validated. Refer to the validation section of the function.
+*
+*******************************************************************************/
+
+extern "C" int __cdecl _wcsnicmp_l (
+        wchar_t const * const lhs,
+        wchar_t const * const rhs,
+        size_t          const count,
+        _locale_t       const plocinfo
+        )
+{
+    /* validation section */
+    _VALIDATE_RETURN(lhs != nullptr, EINVAL, _NLSCMPERROR);
+    _VALIDATE_RETURN(rhs != nullptr, EINVAL, _NLSCMPERROR);
+
+    if (count == 0)
+    {
+        return 0;
+    }
+
+    _LocaleUpdate _loc_update(plocinfo);
+
+    // This check is still worth doing for wide but not narrow because
+    // we need to consult the UTF-16 ctype map for towlower operations.
+    if (_loc_update.GetLocaleT()->locinfo->locale_name[LC_CTYPE] == nullptr)
+    {
+        return __ascii_wcsnicmp(lhs, rhs, count);
+    }
+
+    unsigned short const * lhs_ptr = reinterpret_cast<unsigned short const *>(lhs);
+    unsigned short const * rhs_ptr = reinterpret_cast<unsigned short const *>(rhs);
+
+    int result;
+    int lhs_value;
+    int rhs_value;
+    size_t remaining = count;
+    do
+    {
+        lhs_value = _towlower_internal(*lhs_ptr++, _loc_update.GetLocaleT());
+        rhs_value = _towlower_internal(*rhs_ptr++, _loc_update.GetLocaleT());
+        result = lhs_value - rhs_value;
+    }
+    while (result == 0 && lhs_value != 0 && --remaining != 0);
+
+    return result;
+}
+
+extern "C" int __cdecl __ascii_wcsnicmp(
+        wchar_t const * const lhs,
+        wchar_t const * const rhs,
+        size_t          const count
+        )
+{
+    if (count == 0)
+    {
+        return 0;
+    }
+
+    unsigned short const * lhs_ptr = reinterpret_cast<unsigned short const *>(lhs);
+    unsigned short const * rhs_ptr = reinterpret_cast<unsigned short const *>(rhs);
+
+    int result;
+    int lhs_value;
+    int rhs_value;
+    size_t remaining = count;
+    do
+    {
+        lhs_value = __ascii_towlower(*lhs_ptr++);
+        rhs_value = __ascii_towlower(*rhs_ptr++);
+        result = lhs_value - rhs_value;
+    }
+    while (result == 0 && lhs_value != 0 && --remaining != 0);
+
+    return result;
+}
+
+extern "C" int __cdecl _wcsnicmp (
+        wchar_t const * const lhs,
+        wchar_t const * const rhs,
+        size_t          const count
+        )
+{
+    if (!__acrt_locale_changed())
+    {
+        /* validation section */
+        _VALIDATE_RETURN(lhs != nullptr, EINVAL, _NLSCMPERROR);
+        _VALIDATE_RETURN(rhs != nullptr, EINVAL, _NLSCMPERROR);
+
+        return __ascii_wcsnicmp(lhs, rhs, count);
+    }
+
+    return _wcsnicmp_l(lhs, rhs, count, nullptr);
+}