1 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "base/win/i18n.h"
6
7 #include <windows.h>
8
9 #include "base/logging.h"
10
11 namespace {
12
13 // Keep this enum in sync with kLanguageFunctionNames.
14 enum LanguageFunction {
15 SYSTEM_LANGUAGES,
16 USER_LANGUAGES,
17 PROCESS_LANGUAGES,
18 THREAD_LANGUAGES,
19 NUM_FUNCTIONS
20 };
21
22 const char kSystemLanguagesFunctionName[] = "GetSystemPreferredUILanguages";
23 const char kUserLanguagesFunctionName[] = "GetUserPreferredUILanguages";
24 const char kProcessLanguagesFunctionName[] = "GetProcessPreferredUILanguages";
25 const char kThreadLanguagesFunctionName[] = "GetThreadPreferredUILanguages";
26
27 // Keep this array in sync with enum LanguageFunction.
28 const char *const kLanguageFunctionNames[] = {
29 &kSystemLanguagesFunctionName[0],
30 &kUserLanguagesFunctionName[0],
31 &kProcessLanguagesFunctionName[0],
32 &kThreadLanguagesFunctionName[0]
33 };
34
35 COMPILE_ASSERT(NUM_FUNCTIONS == arraysize(kLanguageFunctionNames),
36 language_function_enum_and_names_out_of_sync);
37
38 // Calls one of the MUI Get*PreferredUILanguages functions, placing the result
39 // in |languages|. |function| identifies the function to call and |flags| is
40 // the function-specific flags (callers must not specify MUI_LANGUAGE_ID or
41 // MUI_LANGUAGE_NAME). Returns true if at least one language is placed in
42 // |languages|.
GetMUIPreferredUILanguageList(LanguageFunction function,ULONG flags,std::vector<wchar_t> * languages)43 bool GetMUIPreferredUILanguageList(LanguageFunction function, ULONG flags,
44 std::vector<wchar_t>* languages) {
45 DCHECK(0 <= function && NUM_FUNCTIONS > function);
46 DCHECK_EQ(0U, (flags & (MUI_LANGUAGE_ID | MUI_LANGUAGE_NAME)));
47 DCHECK(languages);
48
49 HMODULE kernel32 = GetModuleHandle(L"kernel32.dll");
50 if (NULL != kernel32) {
51 typedef BOOL (WINAPI* GetPreferredUILanguages_Fn)(
52 DWORD, PULONG, PZZWSTR, PULONG);
53 GetPreferredUILanguages_Fn get_preferred_ui_languages =
54 reinterpret_cast<GetPreferredUILanguages_Fn>(
55 GetProcAddress(kernel32, kLanguageFunctionNames[function]));
56 if (NULL != get_preferred_ui_languages) {
57 const ULONG call_flags = flags | MUI_LANGUAGE_NAME;
58 ULONG language_count = 0;
59 ULONG buffer_length = 0;
60 if (get_preferred_ui_languages(call_flags, &language_count, NULL,
61 &buffer_length) &&
62 0 != buffer_length) {
63 languages->resize(buffer_length);
64 if (get_preferred_ui_languages(call_flags, &language_count,
65 &(*languages)[0], &buffer_length) &&
66 0 != language_count) {
67 DCHECK(languages->size() == buffer_length);
68 return true;
69 } else {
70 DPCHECK(0 == language_count)
71 << "Failed getting preferred UI languages.";
72 }
73 } else {
74 DPCHECK(0 == buffer_length)
75 << "Failed getting size of preferred UI languages.";
76 }
77 } else {
78 VLOG(2) << "MUI not available.";
79 }
80 } else {
81 NOTREACHED() << "kernel32.dll not found.";
82 }
83
84 return false;
85 }
86
GetUserDefaultUILanguage(std::wstring * language,std::wstring * region)87 bool GetUserDefaultUILanguage(std::wstring* language, std::wstring* region) {
88 DCHECK(language);
89
90 LANGID lang_id = ::GetUserDefaultUILanguage();
91 if (LOCALE_CUSTOM_UI_DEFAULT != lang_id) {
92 const LCID locale_id = MAKELCID(lang_id, SORT_DEFAULT);
93 // max size for LOCALE_SISO639LANGNAME and LOCALE_SISO3166CTRYNAME is 9
94 wchar_t result_buffer[9];
95 int result_length =
96 GetLocaleInfo(locale_id, LOCALE_SISO639LANGNAME, &result_buffer[0],
97 arraysize(result_buffer));
98 DPCHECK(0 != result_length) << "Failed getting language id";
99 if (1 < result_length) {
100 language->assign(&result_buffer[0], result_length - 1);
101 region->clear();
102 if (SUBLANG_NEUTRAL != SUBLANGID(lang_id)) {
103 result_length =
104 GetLocaleInfo(locale_id, LOCALE_SISO3166CTRYNAME, &result_buffer[0],
105 arraysize(result_buffer));
106 DPCHECK(0 != result_length) << "Failed getting region id";
107 if (1 < result_length)
108 region->assign(&result_buffer[0], result_length - 1);
109 }
110 return true;
111 }
112 } else {
113 // This is entirely unexpected on pre-Vista, which is the only time we
114 // should try GetUserDefaultUILanguage anyway.
115 NOTREACHED() << "Cannot determine language for a supplemental locale.";
116 }
117 return false;
118 }
119
GetPreferredUILanguageList(LanguageFunction function,ULONG flags,std::vector<std::wstring> * languages)120 bool GetPreferredUILanguageList(LanguageFunction function, ULONG flags,
121 std::vector<std::wstring>* languages) {
122 std::vector<wchar_t> buffer;
123 std::wstring language;
124 std::wstring region;
125
126 if (GetMUIPreferredUILanguageList(function, flags, &buffer)) {
127 std::vector<wchar_t>::const_iterator scan = buffer.begin();
128 language.assign(&*scan);
129 while (!language.empty()) {
130 languages->push_back(language);
131 scan += language.size() + 1;
132 language.assign(&*scan);
133 }
134 } else if (GetUserDefaultUILanguage(&language, ®ion)) {
135 // Mimic the MUI behavior of putting the neutral version of the lang after
136 // the regional one (e.g., "fr-CA, fr").
137 if (!region.empty())
138 languages->push_back(std::wstring(language)
139 .append(1, L'-')
140 .append(region));
141 languages->push_back(language);
142 } else {
143 return false;
144 }
145
146 return true;
147 }
148
149 } // namespace
150
151 namespace base {
152 namespace win {
153 namespace i18n {
154
GetUserPreferredUILanguageList(std::vector<std::wstring> * languages)155 bool GetUserPreferredUILanguageList(std::vector<std::wstring>* languages) {
156 DCHECK(languages);
157 return GetPreferredUILanguageList(USER_LANGUAGES, 0, languages);
158 }
159
GetThreadPreferredUILanguageList(std::vector<std::wstring> * languages)160 bool GetThreadPreferredUILanguageList(std::vector<std::wstring>* languages) {
161 DCHECK(languages);
162 return GetPreferredUILanguageList(
163 THREAD_LANGUAGES, MUI_MERGE_SYSTEM_FALLBACK | MUI_MERGE_USER_FALLBACK,
164 languages);
165 }
166
167 } // namespace i18n
168 } // namespace win
169 } // namespace base
170