1 /***
2 *towupper.cpp - convert wide character to upper case
3 *
4 * Copyright (c) Microsoft Corporation. All rights reserved.
5 *
6 *Purpose:
7 * Defines towupper().
8 *
9 *******************************************************************************/
10 #include <corecrt_internal.h>
11 #include <ctype.h>
12 #include <locale.h>
13
14 /***
15 *wint_t _towupper_l(c, ptloci) - convert wide character to upper case
16 *
17 *Purpose:
18 * Multi-thread function only! Non-locking version of towupper.
19 *
20 *Entry:
21 *
22 *Exit:
23 *
24 *Exceptions:
25 *
26 *******************************************************************************/
27
_towupper_l(wint_t const c,_locale_t const plocinfo)28 extern "C" wint_t __cdecl _towupper_l(
29 wint_t const c,
30 _locale_t const plocinfo
31 )
32 {
33 if (c == WEOF)
34 {
35 return c;
36 }
37
38 _LocaleUpdate _loc_update(plocinfo);
39 auto const locinfo = _loc_update.GetLocaleT()->locinfo;
40
41 if (locinfo->_public._locale_lc_codepage == CP_UTF8)
42 {
43 // For 128 <= c < 256, the toupper map would consider the wide character as it is in UTF-8, not UTF-16.
44 // Below 128, UTF-8 and UTF-16 have the same encodings, so we can use the table.
45 if (c < 128)
46 {
47 return _towupper_fast_internal(static_cast<unsigned char>(c), _loc_update.GetLocaleT());
48 }
49 }
50 else
51 {
52 // For 128 <= c < 256, the toupper map will consider the wide character as it would be in the current narrow code page,
53 // which can lead to unexpected behavior. This behavior is maintained for backwards compatibility.
54 if (c < 256)
55 {
56 return _towupper_fast_internal(static_cast<unsigned char>(c), _loc_update.GetLocaleT());
57 }
58
59 if (locinfo->locale_name[LC_CTYPE] == nullptr)
60 {
61 // If the locale is C, then the only characters that would be transformed are <256
62 // and have been processed already.
63 return c;
64 }
65 }
66
67 wint_t widechar;
68 if (0 == __acrt_LCMapStringW(
69 locinfo->locale_name[LC_CTYPE],
70 LCMAP_UPPERCASE,
71 (LPCWSTR)&c,
72 1,
73 (LPWSTR)&widechar,
74 1))
75 {
76 return c;
77 }
78
79 return widechar;
80 }
81
82 /***
83 *wint_t towupper(c) - convert wide character to upper case
84 *
85 *Purpose:
86 * towupper() returns the uppercase equivalent of its argument
87 *
88 *Entry:
89 * c - wint_t value of character to be converted
90 *
91 *Exit:
92 * if c is a lower case letter, returns wint_t value of upper case
93 * representation of c. otherwise, it returns c.
94 *
95 *Exceptions:
96 *
97 *******************************************************************************/
98
towupper(wint_t c)99 extern "C" wint_t __cdecl towupper (
100 wint_t c
101 )
102 {
103
104 return _towupper_l(c, nullptr);
105 }
106