Flutter Engine
icu_util.cc
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1 // Copyright 2013 The Flutter 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 "flutter/fml/icu_util.h"
6 
7 #include <memory>
8 #include <mutex>
9 
10 #include "flutter/fml/build_config.h"
11 #include "flutter/fml/logging.h"
12 #include "flutter/fml/mapping.h"
13 #include "flutter/fml/native_library.h"
14 #include "flutter/fml/paths.h"
15 #include "third_party/icu/source/common/unicode/udata.h"
16 
17 namespace fml {
18 namespace icu {
19 
20 class ICUContext {
21  public:
22  explicit ICUContext(const std::string& icu_data_path) : valid_(false) {
23  valid_ = SetupMapping(icu_data_path) && SetupICU();
24  }
25 
26  explicit ICUContext(std::unique_ptr<Mapping> mapping)
27  : mapping_(std::move(mapping)) {
28  valid_ = SetupICU();
29  }
30 
31  ~ICUContext() = default;
32 
33  bool SetupMapping(const std::string& icu_data_path) {
34  // Check if the path exists and it readable directly.
35  auto fd =
36  fml::OpenFile(icu_data_path.c_str(), false, fml::FilePermission::kRead);
37 
38  // Check the path relative to the current executable.
39  if (!fd.is_valid()) {
40  auto directory = fml::paths::GetExecutableDirectoryPath();
41 
42  if (!directory.first) {
43  return false;
44  }
45 
46  std::string path_relative_to_executable =
47  paths::JoinPaths({directory.second, icu_data_path});
48 
49  fd = fml::OpenFile(path_relative_to_executable.c_str(), false,
51  }
52 
53  if (!fd.is_valid()) {
54  return false;
55  }
56 
57  std::initializer_list<FileMapping::Protection> protection = {
59 
60  auto file_mapping =
61  std::make_unique<FileMapping>(fd, std::move(protection));
62 
63  if (file_mapping->GetSize() != 0) {
64  mapping_ = std::move(file_mapping);
65  return true;
66  }
67 
68  return false;
69  }
70 
71  bool SetupICU() {
72  if (GetSize() == 0) {
73  return false;
74  }
75 
76  UErrorCode err_code = U_ZERO_ERROR;
77  udata_setCommonData(GetMapping(), &err_code);
78  return (err_code == U_ZERO_ERROR);
79  }
80 
81  const uint8_t* GetMapping() const {
82  return mapping_ ? mapping_->GetMapping() : nullptr;
83  }
84 
85  size_t GetSize() const { return mapping_ ? mapping_->GetSize() : 0; }
86 
87  bool IsValid() const { return valid_; }
88 
89  private:
90  bool valid_;
91  std::unique_ptr<Mapping> mapping_;
92 
93  FML_DISALLOW_COPY_AND_ASSIGN(ICUContext);
94 };
95 
96 void InitializeICUOnce(const std::string& icu_data_path) {
97  static ICUContext* context = new ICUContext(icu_data_path);
98  FML_CHECK(context->IsValid())
99  << "Must be able to initialize the ICU context. Tried: " << icu_data_path;
100 }
101 
102 std::once_flag g_icu_init_flag;
103 void InitializeICU(const std::string& icu_data_path) {
104  std::call_once(g_icu_init_flag,
105  [&icu_data_path]() { InitializeICUOnce(icu_data_path); });
106 }
107 
108 void InitializeICUFromMappingOnce(std::unique_ptr<Mapping> mapping) {
109  static ICUContext* context = new ICUContext(std::move(mapping));
110  FML_CHECK(context->IsValid())
111  << "Unable to initialize the ICU context from a mapping.";
112 }
113 
114 void InitializeICUFromMapping(std::unique_ptr<Mapping> mapping) {
115  std::call_once(g_icu_init_flag, [mapping = std::move(mapping)]() mutable {
116  InitializeICUFromMappingOnce(std::move(mapping));
117  });
118 }
119 
120 } // namespace icu
121 } // namespace fml
void InitializeICUFromMappingOnce(std::unique_ptr< Mapping > mapping)
Definition: icu_util.cc:108
void InitializeICU(const std::string &icu_data_path)
Definition: icu_util.cc:103
void InitializeICUFromMapping(std::unique_ptr< Mapping > mapping)
Definition: icu_util.cc:114
Definition: ref_ptr.h:252
std::once_flag g_icu_init_flag
Definition: icu_util.cc:102
bool SetupMapping(const std::string &icu_data_path)
Definition: icu_util.cc:33
Definition: ascii_trie.cc:9
std::pair< bool, std::string > GetExecutableDirectoryPath()
std::string JoinPaths(std::initializer_list< std::string > components)
Definition: paths.cc:14
ICUContext(const std::string &icu_data_path)
Definition: icu_util.cc:22
ICUContext(std::unique_ptr< Mapping > mapping)
Definition: icu_util.cc:26
#define FML_CHECK(condition)
Definition: logging.h:68
size_t GetSize() const
Definition: icu_util.cc:85
const uint8_t * GetMapping() const
Definition: icu_util.cc:81
fml::UniqueFD OpenFile(const char *path, bool create_if_necessary, FilePermission permission)
This can open a directory on POSIX, but not on Windows.
Definition: file_posix.cc:64
void InitializeICUOnce(const std::string &icu_data_path)
Definition: icu_util.cc:96
bool IsValid() const
Definition: icu_util.cc:87