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
130
131
132
133
134
|
/*
* Copyright (c) 2019-2020, Sergey Bugaev <bugaevc@serenityos.org>
* Copyright (c) 2021, Max Wipfli <mail@maxwipfli.ch>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/String.h>
#include <AK/StringView.h>
#include <AK/Types.h>
namespace AK {
class Utf8View;
class Utf8CodePointIterator {
friend class Utf8View;
public:
Utf8CodePointIterator() = default;
~Utf8CodePointIterator() = default;
bool operator==(Utf8CodePointIterator const&) const = default;
bool operator!=(Utf8CodePointIterator const&) const = default;
Utf8CodePointIterator& operator++();
u32 operator*() const;
// NOTE: This returns {} if the peek is at or past EOF.
Optional<u32> peek(size_t offset = 0) const;
ssize_t operator-(const Utf8CodePointIterator& other) const
{
return m_ptr - other.m_ptr;
}
// Note : These methods return the information about the underlying UTF-8 bytes.
// If the UTF-8 string encoding is not valid at the iterator's position, then the underlying bytes might be different from the
// decoded character's re-encoded bytes (which will be an `0xFFFD REPLACEMENT CHARACTER` with an UTF-8 length of three bytes).
// If your code relies on the decoded character being equivalent to the re-encoded character, use the `UTF8View::validate()`
// method on the view prior to using its iterator.
size_t underlying_code_point_length_in_bytes() const;
ReadonlyBytes underlying_code_point_bytes() const;
bool done() const { return m_length == 0; }
private:
Utf8CodePointIterator(u8 const* ptr, size_t length)
: m_ptr(ptr)
, m_length(length)
{
}
u8 const* m_ptr { nullptr };
size_t m_length { 0 };
};
class Utf8View {
public:
using Iterator = Utf8CodePointIterator;
Utf8View() = default;
explicit Utf8View(String& string)
: m_string(string.view())
{
}
explicit Utf8View(StringView string)
: m_string(string)
{
}
~Utf8View() = default;
explicit Utf8View(String&&) = delete;
const StringView& as_string() const { return m_string; }
Utf8CodePointIterator begin() const { return { begin_ptr(), m_string.length() }; }
Utf8CodePointIterator end() const { return { end_ptr(), 0 }; }
Utf8CodePointIterator iterator_at_byte_offset(size_t) const;
const unsigned char* bytes() const { return begin_ptr(); }
size_t byte_length() const { return m_string.length(); }
size_t byte_offset_of(const Utf8CodePointIterator&) const;
size_t byte_offset_of(size_t code_point_offset) const;
Utf8View substring_view(size_t byte_offset, size_t byte_length) const { return Utf8View { m_string.substring_view(byte_offset, byte_length) }; }
Utf8View substring_view(size_t byte_offset) const { return substring_view(byte_offset, byte_length() - byte_offset); }
Utf8View unicode_substring_view(size_t code_point_offset, size_t code_point_length) const;
Utf8View unicode_substring_view(size_t code_point_offset) const { return unicode_substring_view(code_point_offset, length() - code_point_offset); }
bool is_empty() const { return m_string.is_empty(); }
bool is_null() const { return m_string.is_null(); }
bool starts_with(const Utf8View&) const;
bool contains(u32) const;
Utf8View trim(const Utf8View& characters, TrimMode mode = TrimMode::Both) const;
size_t iterator_offset(const Utf8CodePointIterator& it) const
{
return byte_offset_of(it);
}
bool validate(size_t& valid_bytes) const;
bool validate() const
{
size_t valid_bytes;
return validate(valid_bytes);
}
size_t length() const
{
if (!m_have_length) {
m_length = calculate_length();
m_have_length = true;
}
return m_length;
}
private:
u8 const* begin_ptr() const { return (u8 const*)m_string.characters_without_null_termination(); }
u8 const* end_ptr() const { return begin_ptr() + m_string.length(); }
size_t calculate_length() const;
StringView m_string;
mutable size_t m_length { 0 };
mutable bool m_have_length { false };
};
}
using AK::Utf8CodePointIterator;
using AK::Utf8View;
|
