1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef ANDROID_BASE_UTF8_H
18 #define ANDROID_BASE_UTF8_H
19 
20 #ifdef _WIN32
21 #include <string>
22 #else
23 // Bring in prototypes for standard APIs so that we can import them into the utf8 namespace.
24 #include <fcntl.h>      // open
25 #include <stdio.h>      // fopen
26 #include <sys/stat.h>   // mkdir
27 #include <unistd.h>     // unlink
28 #endif
29 
30 namespace android {
31 namespace base {
32 
33 // Only available on Windows because this is only needed on Windows.
34 #ifdef _WIN32
35 // Convert size number of UTF-16 wchar_t's to UTF-8. Returns whether the
36 // conversion was done successfully.
37 bool WideToUTF8(const wchar_t* utf16, const size_t size, std::string* utf8);
38 
39 // Convert a NULL-terminated string of UTF-16 characters to UTF-8. Returns
40 // whether the conversion was done successfully.
41 bool WideToUTF8(const wchar_t* utf16, std::string* utf8);
42 
43 // Convert a UTF-16 std::wstring (including any embedded NULL characters) to
44 // UTF-8. Returns whether the conversion was done successfully.
45 bool WideToUTF8(const std::wstring& utf16, std::string* utf8);
46 
47 // Convert size number of UTF-8 char's to UTF-16. Returns whether the conversion
48 // was done successfully.
49 bool UTF8ToWide(const char* utf8, const size_t size, std::wstring* utf16);
50 
51 // Convert a NULL-terminated string of UTF-8 characters to UTF-16. Returns
52 // whether the conversion was done successfully.
53 bool UTF8ToWide(const char* utf8, std::wstring* utf16);
54 
55 // Convert a UTF-8 std::string (including any embedded NULL characters) to
56 // UTF-16. Returns whether the conversion was done successfully.
57 bool UTF8ToWide(const std::string& utf8, std::wstring* utf16);
58 
59 // Convert a file system path, represented as a NULL-terminated string of
60 // UTF-8 characters, to a UTF-16 string representing the same file system
61 // path using the Windows extended-lengh path representation.
62 //
63 // See https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247(v=vs.85).aspx#MAXPATH:
64 //   ```The Windows API has many functions that also have Unicode versions to
65 //   permit an extended-length path for a maximum total path length of 32,767
66 //   characters. To specify an extended-length path, use the "\\?\" prefix.
67 //   For example, "\\?\D:\very long path".```
68 //
69 // Returns whether the conversion was done successfully.
70 bool UTF8PathToWindowsLongPath(const char* utf8, std::wstring* utf16);
71 #endif
72 
73 // The functions in the utf8 namespace take UTF-8 strings. For Windows, these
74 // are wrappers, for non-Windows these just expose existing APIs. To call these
75 // functions, use:
76 //
77 // // anonymous namespace to avoid conflict with existing open(), unlink(), etc.
78 // namespace {
79 //   // Import functions into anonymous namespace.
80 //   using namespace android::base::utf8;
81 //
82 //   void SomeFunction(const char* name) {
83 //     int fd = open(name, ...);  // Calls android::base::utf8::open().
84 //     ...
85 //     unlink(name);              // Calls android::base::utf8::unlink().
86 //   }
87 // }
88 namespace utf8 {
89 
90 #ifdef _WIN32
91 FILE* fopen(const char* name, const char* mode);
92 int mkdir(const char* name, mode_t mode);
93 int open(const char* name, int flags, ...);
94 int unlink(const char* name);
95 #else
96 using ::fopen;
97 using ::mkdir;
98 using ::open;
99 using ::unlink;
100 #endif
101 
102 }  // namespace utf8
103 }  // namespace base
104 }  // namespace android
105 
106 #endif  // ANDROID_BASE_UTF8_H
107