1// Copyright (C) 2017 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Marc Mutz <marc.mutz@kdab.com>
2// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
3
4#ifndef QSTRINGALGORITHMS_H
5#define QSTRINGALGORITHMS_H
6
7#include <QtCore/qbytearrayalgorithms.h>
8#include <QtCore/qcontainerfwd.h>
9#include <QtCore/qnamespace.h>
10#include <QtCore/qstringfwd.h>
11#if 0
12#pragma qt_class(QStringAlgorithms)
13#endif
14
15#include <algorithm> // std::find
16#include <iterator> // std::size
17
18#include <QtCore/q20type_traits.h> // q20::is_constant_evaluated
19
20QT_BEGIN_NAMESPACE
21
22namespace QtPrivate {
23
24[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype qustrlen(const char16_t *str) noexcept;
25[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype qustrnlen(const char16_t *str, qsizetype maxlen) noexcept;
26[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION const char16_t *qustrchr(QStringView str, char16_t ch) noexcept;
27
28[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QStringView lhs, QStringView rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
29[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QStringView lhs, QLatin1StringView rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
30[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QStringView lhs, QBasicUtf8StringView<false> rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
31[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QLatin1StringView lhs, QStringView rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
32[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QLatin1StringView lhs, QLatin1StringView rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
33[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QLatin1StringView lhs, QBasicUtf8StringView<false> rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
34[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QBasicUtf8StringView<false> lhs, QStringView rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
35[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QBasicUtf8StringView<false> lhs, QLatin1StringView rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
36[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QBasicUtf8StringView<false> lhs, QBasicUtf8StringView<false> rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
37
38[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QStringView lhs, QStringView rhs) noexcept;
39[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QStringView lhs, QLatin1StringView rhs) noexcept;
40[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QStringView lhs, QBasicUtf8StringView<false> rhs) noexcept;
41[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QLatin1StringView lhs, QStringView rhs) noexcept;
42[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QLatin1StringView lhs, QLatin1StringView rhs) noexcept;
43[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QLatin1StringView lhs, QBasicUtf8StringView<false> rhs) noexcept;
44[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QBasicUtf8StringView<false> lhs, QStringView rhs) noexcept;
45[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QBasicUtf8StringView<false> lhs, QLatin1StringView rhs) noexcept;
46[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QBasicUtf8StringView<false> lhs, QBasicUtf8StringView<false> rhs) noexcept;
47
48[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool startsWith(QStringView haystack, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
49[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool startsWith(QStringView haystack, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
50[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool startsWith(QLatin1StringView haystack, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
51[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool startsWith(QLatin1StringView haystack, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
52
53[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool endsWith(QStringView haystack, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
54[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool endsWith(QStringView haystack, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
55[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool endsWith(QLatin1StringView haystack, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
56[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool endsWith(QLatin1StringView haystack, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
57
58[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype findString(QStringView haystack, qsizetype from, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
59[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype findString(QStringView haystack, qsizetype from, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
60[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype findString(QLatin1StringView haystack, qsizetype from, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
61[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype findString(QLatin1StringView haystack, qsizetype from, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
62
63[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype lastIndexOf(QStringView haystack, qsizetype from, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
64[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype lastIndexOf(QStringView haystack, qsizetype from, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
65[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype lastIndexOf(QLatin1StringView haystack, qsizetype from, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
66[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype lastIndexOf(QLatin1StringView haystack, qsizetype from, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
67
68[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION QStringView trimmed(QStringView s) noexcept;
69[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION QLatin1StringView trimmed(QLatin1StringView s) noexcept;
70
71[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isLower(QStringView s) noexcept;
72[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isUpper(QStringView s) noexcept;
73
74[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype count(QStringView haystack, QChar needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
75[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype count(QStringView haystack, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
76[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype count(QStringView haystack, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive);
77[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype count(QLatin1StringView haystack, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive);
78[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype count(QLatin1StringView haystack, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive);
79[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype count(QLatin1StringView haystack, QChar needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
80
81#if QT_CONFIG(regularexpression)
82// ### Qt 7: unify these overloads;
83// remove the ones taking only a QStringView, export the others, adjust callers
84[[nodiscard]] qsizetype indexOf(QStringView viewHaystack,
85 const QString *stringHaystack,
86 const QRegularExpression &re,
87 qsizetype from = 0,
88 QRegularExpressionMatch *rmatch = nullptr);
89[[nodiscard]] Q_CORE_EXPORT qsizetype indexOf(QStringView haystack,
90 const QRegularExpression &re,
91 qsizetype from = 0,
92 QRegularExpressionMatch *rmatch = nullptr);
93[[nodiscard]] qsizetype lastIndexOf(QStringView viewHaystack,
94 const QString *stringHaystack,
95 const QRegularExpression &re,
96 qsizetype from = -1,
97 QRegularExpressionMatch *rmatch = nullptr);
98[[nodiscard]] Q_CORE_EXPORT qsizetype lastIndexOf(QStringView haystack,
99 const QRegularExpression &re,
100 qsizetype from = -1,
101 QRegularExpressionMatch *rmatch = nullptr);
102[[nodiscard]] bool contains(QStringView viewHaystack,
103 const QString *stringHaystack,
104 const QRegularExpression &re,
105 QRegularExpressionMatch *rmatch = nullptr);
106[[nodiscard]] Q_CORE_EXPORT bool contains(QStringView haystack,
107 const QRegularExpression &re,
108 QRegularExpressionMatch *rmatch = nullptr);
109[[nodiscard]] Q_CORE_EXPORT qsizetype count(QStringView haystack, const QRegularExpression &re);
110#endif
111
112[[nodiscard]] Q_CORE_EXPORT QString convertToQString(QAnyStringView s);
113
114[[nodiscard]] Q_CORE_EXPORT QByteArray convertToLatin1(QStringView str);
115[[nodiscard]] Q_CORE_EXPORT QByteArray convertToUtf8(QStringView str);
116[[nodiscard]] Q_CORE_EXPORT QByteArray convertToLocal8Bit(QStringView str);
117[[nodiscard]] Q_CORE_EXPORT QList<uint> convertToUcs4(QStringView str); // ### Qt 7 char32_t
118
119[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isRightToLeft(QStringView string) noexcept;
120
121[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isAscii(QLatin1StringView s) noexcept;
122[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isAscii(QStringView s) noexcept;
123[[nodiscard]] constexpr inline bool isLatin1(QLatin1StringView s) noexcept;
124[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isLatin1(QStringView s) noexcept;
125[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isValidUtf16(QStringView s) noexcept;
126
127template <typename Char, size_t N> [[nodiscard]] constexpr Q_ALWAYS_INLINE
128qsizetype lengthHelperContainerLoop(const Char (&str)[N])
129{
130#if defined(__cpp_lib_constexpr_algorithms) && defined(Q_CC_GNU_ONLY)
131 // libstdc++'s std::find / std::find_if manages to execute more steps
132 // than the loop below
133 const auto it = std::find(str, str + N, Char(0));
134 return it - str;
135#else
136 // std::char_traits<C> is deprecated for C not one of the standard char
137 // types, so we have to roll out our own loop.
138 for (size_t i = 0; i < N; ++i) {
139 if (str[i] == Char(0))
140 return qsizetype(i);
141 }
142 return qsizetype(N);
143#endif
144}
145
146template <typename Char, size_t N> [[nodiscard]] constexpr Q_ALWAYS_INLINE
147std::enable_if_t<sizeof(Char) == sizeof(char16_t), qsizetype>
148lengthHelperContainer(const Char (&str)[N])
149{
150 // The following values were empirically determined to detect the threshold
151 // at which the compiler gives up pre-calculating the std::find() below and
152 // instead inserts code to be executed at runtime.
153 constexpr size_t RuntimeThreshold =
154#if defined(Q_CC_CLANG)
155 // tested on Clang 15, 16 & 17
156 1023
157#elif defined(Q_CC_GNU)
158 // tested through GCC 13.1 at -O3 compilation level
159 // note: at -O2, GCC always generates a loop!
160 __cplusplus >= 202002L ? 39 : 17
161#else
162 0
163#endif
164 ;
165 if constexpr (N == 1) {
166 return str[0] == Char(0) ? 0 : 1;
167 } else if constexpr (N > RuntimeThreshold) {
168#ifdef QT_SUPPORTS_IS_CONSTANT_EVALUATED
169 if (!q20::is_constant_evaluated())
170 return QtPrivate::qustrnlen(str: reinterpret_cast<const char16_t *>(str), maxlen: N);
171#endif
172 }
173
174 return lengthHelperContainerLoop(str);
175}
176
177inline qsizetype qstrnlen_helper(const char *str, size_t maxlen)
178{
179#if !defined(Q_COMPILER_SLOW_QSTRNLEN_COMPILATION)
180 return qstrnlen(str, maxlen);
181#else
182 return strnlen_s(str, maxlen);
183#endif
184}
185
186template <typename Char, size_t N> [[nodiscard]] constexpr inline
187std::enable_if_t<sizeof(Char) == 1, qsizetype> lengthHelperContainer(const Char (&str)[N])
188{
189#ifdef QT_SUPPORTS_IS_CONSTANT_EVALUATED
190 if (!q20::is_constant_evaluated())
191 return qstrnlen_helper(str: reinterpret_cast<const char *>(str), maxlen: N);
192#endif
193
194 return lengthHelperContainerLoop(str);
195}
196
197template <typename Container>
198constexpr qsizetype lengthHelperContainer(const Container &c) noexcept
199{
200 return qsizetype(std::size(c));
201}
202} // namespace QtPrivate
203
204QT_END_NAMESPACE
205
206#endif // QSTRINGALGORTIHMS_H
207