1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
|
#include "cru/win/String.hpp"
#include "cru/win/Exception.hpp"
#include <type_traits>
namespace cru::platform::win {
std::string ToUtf8String(const std::wstring_view& string) {
if (string.empty()) return std::string{};
const auto length = ::WideCharToMultiByte(
CP_UTF8, WC_ERR_INVALID_CHARS, string.data(),
static_cast<int>(string.size()), nullptr, 0, nullptr, nullptr);
if (length == 0) {
throw Win32Error(::GetLastError(),
"Failed to convert wide string to UTF-8.");
}
std::string result;
result.resize(length);
if (::WideCharToMultiByte(CP_UTF8, WC_ERR_INVALID_CHARS, string.data(),
static_cast<int>(string.size()), result.data(),
static_cast<int>(result.size()), nullptr,
nullptr) == 0)
throw Win32Error(::GetLastError(),
"Failed to convert wide string to UTF-8.");
return result;
}
std::wstring ToUtf16String(const std::string_view& string) {
if (string.empty()) return std::wstring{};
const auto length =
::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, string.data(),
static_cast<int>(string.size()), nullptr, 0);
if (length == 0) {
throw Win32Error(::GetLastError(),
"Failed to convert wide string to UTF-16.");
}
std::wstring result;
result.resize(length);
if (::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, string.data(),
static_cast<int>(string.size()), result.data(),
static_cast<int>(result.size())) == 0)
throw win::Win32Error(::GetLastError(),
"Failed to convert wide string to UTF-16.");
return result;
}
template <typename UInt, int number_of_bit>
inline std::enable_if_t<std::is_unsigned_v<UInt>, CodePoint> ExtractBits(
UInt n) {
return static_cast<CodePoint>(n & ((1u << number_of_bit) - 1));
}
CodePoint Utf16Iterator::Next() {
if (position_ == static_cast<Index>(string_.length()))
return k_code_point_end;
const auto cu0 = static_cast<std::uint16_t>(string_[position_++]);
if (cu0 < 0xd800u || cu0 >= 0xe000u) { // 1-length code point
return static_cast<CodePoint>(cu0);
} else if (cu0 <= 0xdbffu) { // 2-length code point
if (position_ == static_cast<Index>(string_.length())) {
throw TextEncodeException(
"Unexpected end when reading second code unit of surrogate pair.");
}
const auto cu1 = static_cast<std::uint16_t>(string_[position_++]);
#ifdef CRU_DEBUG
if (cu1 < 0xDC00u || cu1 > 0xdfffu) {
throw TextEncodeException(
"Unexpected bad-format second code unit of surrogate pair.");
}
#endif
const auto s0 = ExtractBits<std::uint16_t, 10>(cu0) << 10;
const auto s1 = ExtractBits<std::uint16_t, 10>(cu1);
return s0 + s1 + 0x10000;
} else {
throw TextEncodeException(
"Unexpected bad-format first code unit of surrogate pair.");
}
}
Index IndexUtf8ToUtf16(const std::string_view& utf8_string, Index utf8_index,
const std::wstring_view& utf16_string) {
if (utf8_index >= static_cast<Index>(utf8_string.length()))
return utf16_string.length();
Index cp_index = 0;
Utf8Iterator iter{utf8_string};
while (iter.CurrentPosition() <= utf8_index) {
iter.Next();
cp_index++;
}
Utf16Iterator result_iter{utf16_string};
for (Index i = 0; i < cp_index - 1; i++) {
if (result_iter.Next() == k_code_point_end) break;
}
return result_iter.CurrentPosition();
}
Index IndexUtf16ToUtf8(const std::wstring_view& utf16_string, Index utf16_index,
const std::string_view& utf8_string) {
if (utf16_index >= static_cast<Index>(utf16_string.length()))
return utf8_string.length();
Index cp_index = 0;
Utf16Iterator iter{utf16_string};
while (iter.CurrentPosition() <= utf16_index) {
iter.Next();
cp_index++;
}
Utf8Iterator result_iter{utf8_string};
for (Index i = 0; i < cp_index - 1; i++) {
if (result_iter.Next() == k_code_point_end) break;
}
return result_iter.CurrentPosition();
}
} // namespace cru::platform::win
|