xref: /aosp_15_r20/external/cronet/base/win/scoped_hstring.h (revision 6777b5387eb2ff775bb5750e3f5d96f37fb7352b)
1 // Copyright 2017 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef BASE_WIN_SCOPED_HSTRING_H_
6 #define BASE_WIN_SCOPED_HSTRING_H_
7 
8 #include <hstring.h>
9 
10 #include <string>
11 #include <string_view>
12 
13 #include "base/scoped_generic.h"
14 
15 namespace base {
16 
17 namespace internal {
18 
19 // Scoped HSTRING class to maintain lifetime of HSTRINGs allocated with
20 // WindowsCreateString().
21 struct BASE_EXPORT ScopedHStringTraits {
InvalidValueScopedHStringTraits22   static HSTRING InvalidValue() { return nullptr; }
23   static void Free(HSTRING hstr);
24 };
25 
26 }  // namespace internal
27 
28 namespace win {
29 
30 // ScopedHString is a wrapper around an HSTRING.
31 //
32 // Example use:
33 //
34 //   ScopedHString string = ScopedHString::Create(L"abc");
35 //
36 // Also:
37 //
38 //   HSTRING win_string;
39 //   HRESULT hr = WindowsCreateString(..., &win_string);
40 //   ScopedHString string(win_string);
41 //
42 class BASE_EXPORT ScopedHString
43     : public ScopedGeneric<HSTRING, base::internal::ScopedHStringTraits> {
44  public:
45   // Constructs a ScopedHString from an HSTRING, and takes ownership of |hstr|.
46   explicit ScopedHString(HSTRING hstr);
47 
48   static ScopedHString Create(std::wstring_view str);
49   static ScopedHString Create(std::string_view str);
50 
51   // Returns a view into the memory buffer managed by the instance. The returned
52   // std::string_view is only valid during the lifetime of this ScopedHString
53   // instance.
54   std::wstring_view Get() const;
55 
56   // Returns a copy of the instance as a UTF-8 string.
57   std::string GetAsUTF8() const;
58 };
59 
60 }  // namespace win
61 }  // namespace base
62 
63 #endif  // BASE_WIN_SCOPED_HSTRING_H_
64