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[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION const char16_t *qustrcasechr(QStringView str, char16_t ch) noexcept;
28
29[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QStringView lhs, QStringView rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
30[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QStringView lhs, QLatin1StringView rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
31[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QStringView lhs, QBasicUtf8StringView<false> rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
32[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QLatin1StringView lhs, QStringView rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
33[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QLatin1StringView lhs, QLatin1StringView rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
34[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QLatin1StringView lhs, QBasicUtf8StringView<false> rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
35[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QBasicUtf8StringView<false> lhs, QStringView rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
36[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QBasicUtf8StringView<false> lhs, QLatin1StringView rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
37[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION int compareStrings(QBasicUtf8StringView<false> lhs, QBasicUtf8StringView<false> rhs, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
38
39[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QStringView lhs, QStringView rhs) noexcept;
40[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QStringView lhs, QLatin1StringView rhs) noexcept;
41[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QStringView lhs, QBasicUtf8StringView<false> rhs) noexcept;
42[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QLatin1StringView lhs, QStringView rhs) noexcept;
43[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QLatin1StringView lhs, QLatin1StringView rhs) noexcept;
44[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QLatin1StringView lhs, QBasicUtf8StringView<false> rhs) noexcept;
45[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QBasicUtf8StringView<false> lhs, QStringView rhs) noexcept;
46[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QBasicUtf8StringView<false> lhs, QLatin1StringView rhs) noexcept;
47[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool equalStrings(QBasicUtf8StringView<false> lhs, QBasicUtf8StringView<false> rhs) noexcept;
48
49[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool startsWith(QStringView haystack, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
50[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool startsWith(QStringView haystack, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
51[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool startsWith(QLatin1StringView haystack, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
52[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool startsWith(QLatin1StringView haystack, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
53
54[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool endsWith(QStringView haystack, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
55[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool endsWith(QStringView haystack, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
56[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool endsWith(QLatin1StringView haystack, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
57[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool endsWith(QLatin1StringView haystack, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
58
59[[nodiscard]] inline qsizetype findString(QStringView str, qsizetype from, QChar needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
60[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype findString(QStringView haystack, qsizetype from, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
61[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype findString(QStringView haystack, qsizetype from, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
62[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype findString(QLatin1StringView haystack, qsizetype from, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
63[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype findString(QLatin1StringView haystack, qsizetype from, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
64
65[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype lastIndexOf(QStringView haystack, qsizetype from, char16_t needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
66[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype lastIndexOf(QStringView haystack, qsizetype from, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
67[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype lastIndexOf(QStringView haystack, qsizetype from, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
68[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype lastIndexOf(QLatin1StringView haystack, qsizetype from, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
69[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype lastIndexOf(QLatin1StringView haystack, qsizetype from, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
70
71[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION QStringView trimmed(QStringView s) noexcept;
72[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION QLatin1StringView trimmed(QLatin1StringView s) noexcept;
73
74[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isLower(QStringView s) noexcept;
75[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isUpper(QStringView s) noexcept;
76
77[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype count(QStringView haystack, QChar needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
78[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype count(QStringView haystack, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
79[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype count(QStringView haystack, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive);
80[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype count(QLatin1StringView haystack, QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive);
81[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype count(QLatin1StringView haystack, QStringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive);
82[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION qsizetype count(QLatin1StringView haystack, QChar needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
83
84#if QT_CONFIG(regularexpression)
85// ### Qt 7: unify these overloads;
86// remove the ones taking only a QStringView, export the others, adjust callers
87[[nodiscard]] qsizetype indexOf(QStringView viewHaystack,
88 const QString *stringHaystack,
89 const QRegularExpression &re,
90 qsizetype from = 0,
91 QRegularExpressionMatch *rmatch = nullptr);
92[[nodiscard]] Q_CORE_EXPORT qsizetype indexOf(QStringView haystack,
93 const QRegularExpression &re,
94 qsizetype from = 0,
95 QRegularExpressionMatch *rmatch = nullptr);
96[[nodiscard]] qsizetype lastIndexOf(QStringView viewHaystack,
97 const QString *stringHaystack,
98 const QRegularExpression &re,
99 qsizetype from = -1,
100 QRegularExpressionMatch *rmatch = nullptr);
101[[nodiscard]] Q_CORE_EXPORT qsizetype lastIndexOf(QStringView haystack,
102 const QRegularExpression &re,
103 qsizetype from = -1,
104 QRegularExpressionMatch *rmatch = nullptr);
105[[nodiscard]] bool contains(QStringView viewHaystack,
106 const QString *stringHaystack,
107 const QRegularExpression &re,
108 QRegularExpressionMatch *rmatch = nullptr);
109[[nodiscard]] Q_CORE_EXPORT bool contains(QStringView haystack,
110 const QRegularExpression &re,
111 QRegularExpressionMatch *rmatch = nullptr);
112[[nodiscard]] Q_CORE_EXPORT qsizetype count(QStringView haystack, const QRegularExpression &re);
113#endif
114
115[[nodiscard]] Q_CORE_EXPORT QString convertToQString(QAnyStringView s);
116
117[[nodiscard]] Q_CORE_EXPORT QByteArray convertToLatin1(QStringView str);
118[[nodiscard]] Q_CORE_EXPORT QByteArray convertToUtf8(QStringView str);
119[[nodiscard]] Q_CORE_EXPORT QByteArray convertToLocal8Bit(QStringView str);
120[[nodiscard]] Q_CORE_EXPORT QList<uint> convertToUcs4(QStringView str); // ### Qt 7 char32_t
121
122[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isRightToLeft(QStringView string) noexcept;
123
124[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isAscii(QLatin1StringView s) noexcept;
125[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isAscii(QStringView s) noexcept;
126[[nodiscard]] constexpr inline bool isLatin1(QLatin1StringView s) noexcept;
127[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isLatin1(QStringView s) noexcept;
128[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION bool isValidUtf16(QStringView s) noexcept;
129
130template <typename Char, size_t N> [[nodiscard]] constexpr Q_ALWAYS_INLINE
131qsizetype lengthHelperContainerLoop(const Char (&str)[N])
132{
133#if defined(__cpp_lib_constexpr_algorithms) && defined(Q_CC_GNU_ONLY)
134 // libstdc++'s std::find / std::find_if manages to execute more steps
135 // than the loop below
136 const auto it = std::find(str, str + N, Char(0));
137 return it - str;
138#else
139 // std::char_traits<C> is deprecated for C not one of the standard char
140 // types, so we have to roll out our own loop.
141 for (size_t i = 0; i < N; ++i) {
142 if (str[i] == Char(0))
143 return qsizetype(i);
144 }
145 return qsizetype(N);
146#endif
147}
148
149template <typename Char, size_t N> [[nodiscard]] constexpr Q_ALWAYS_INLINE
150std::enable_if_t<sizeof(Char) == sizeof(char16_t), qsizetype>
151lengthHelperContainer(const Char (&str)[N])
152{
153 // The following values were empirically determined to detect the threshold
154 // at which the compiler gives up pre-calculating the std::find() below and
155 // instead inserts code to be executed at runtime.
156 constexpr size_t RuntimeThreshold =
157#if defined(Q_CC_CLANG)
158 // tested on Clang 15, 16 & 17
159 1023
160#elif defined(Q_CC_GNU)
161 // tested through GCC 13.1 at -O3 compilation level
162 // note: at -O2, GCC always generates a loop!
163 __cplusplus >= 202002L ? 39 : 17
164#else
165 0
166#endif
167 ;
168 if constexpr (N == 1) {
169 return str[0] == Char(0) ? 0 : 1;
170 } else if constexpr (N > RuntimeThreshold) {
171#ifdef QT_SUPPORTS_IS_CONSTANT_EVALUATED
172 if (!q20::is_constant_evaluated())
173 return QtPrivate::qustrnlen(str: reinterpret_cast<const char16_t *>(str), maxlen: N);
174#endif
175 }
176
177 return lengthHelperContainerLoop(str);
178}
179
180inline qsizetype qstrnlen_helper(const char *str, size_t maxlen)
181{
182#if !defined(Q_COMPILER_SLOW_QSTRNLEN_COMPILATION)
183 return qstrnlen(str, maxlen);
184#else
185 return strnlen_s(str, maxlen);
186#endif
187}
188
189template <typename Char, size_t N> [[nodiscard]] constexpr inline
190std::enable_if_t<sizeof(Char) == 1, qsizetype> lengthHelperContainer(const Char (&str)[N])
191{
192#ifdef QT_SUPPORTS_IS_CONSTANT_EVALUATED
193 if (!q20::is_constant_evaluated())
194 return qstrnlen_helper(str: reinterpret_cast<const char *>(str), maxlen: N);
195#endif
196
197 return lengthHelperContainerLoop(str);
198}
199
200template <typename Container>
201constexpr qsizetype lengthHelperContainer(const Container &c) noexcept
202{
203 return qsizetype(std::size(c));
204}
205} // namespace QtPrivate
206
207QT_END_NAMESPACE
208
209#endif // QSTRINGALGORTIHMS_H
210

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source code of qtbase/src/corelib/text/qstringalgorithms.h