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
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
/****************************************************************************
**
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "qstringbuilder.h"
#include <QtCore/qtextcodec.h>
QT_BEGIN_NAMESPACE
/*!
\class QLatin1Literal
\internal
\reentrant
\since 4.6
\brief The QLatin1Literal class provides a thin wrapper around string
literals used in source code.
\ingroup tools
\ingroup shared
\ingroup string-processing
Unlike \c QLatin1String, a \c QLatin1Literal can retrieve its size
without iterating over the literal.
The main use of \c QLatin1Literal is in conjunction with \c QStringBuilder
to reduce the number of reallocations needed to build up a string from
smaller chunks.
\sa QStringBuilder, QLatin1String, QString, QStringRef
*/
/*! \fn int QLatin1Literal::size() const
Returns the number of characters in the literal \e{excluding} the trailing
NULL char.
*/
/*! \fn QLatin1Literal::QLatin1Literal(const char str)
Constructs a new literal from the string \a str.
*/
/*! \fn const char *QLatin1Literal::data() const
Returns a pointer to the first character of the string literal.
The string literal is terminated by a NUL character.
*/
/*!
\class QStringBuilder
\internal
\reentrant
\since 4.6
\brief The QStringBuilder class is a template class that provides a facility to build up QStrings from smaller chunks.
\ingroup tools
\ingroup shared
\ingroup string-processing
To build a QString by multiple concatenations, QString::operator+()
is typically used. This causes \e{n - 1} reallocations when building
a string from \e{n} chunks.
QStringBuilder uses expression templates to collect the individual
chunks, compute the total size, allocate the required amount of
memory for the final QString object, and copy the chunks into the
allocated memory.
The QStringBuilder class is not to be used explicitly in user
code. Instances of the class are created as return values of the
operator%() function, acting on objects of type QString,
QLatin1String, QLatin1Literal, QStringRef, QChar, QCharRef,
QLatin1Char, and \c char.
Concatenating strings with operator%() generally yields better
performance then using \c QString::operator+() on the same chunks
if there are three or more of them, and performs equally well in other
cases.
\sa QLatin1Literal, QString
*/
/*! \fn QStringBuilder::QStringBuilder(const A &a, const B &b)
Constructs a QStringBuilder from \a a and \a b.
*/
/* \fn QStringBuilder::operator%(const A &a, const B &b)
Returns a \c QStringBuilder object that is converted to a QString object
when assigned to a variable of QString type or passed to a function that
takes a QString parameter.
This function is usable with arguments of type \c QString,
\c QLatin1String, \c QLatin1Literal, \c QStringRef,
\c QChar, \c QCharRef, \c QLatin1Char, and \c char.
*/
/*! \fn QByteArray QStringBuilder::toLatin1() const
Returns a Latin-1 representation of the string as a QByteArray. The
returned byte array is undefined if the string contains non-Latin1
characters.
*/
/*!
\fn operator QStringBuilder::QString() const
Converts the \c QLatin1Literal into a \c QString object.
*/
/*! \internal
Note: The len contains the ending \0
*/
void QAbstractConcatenable::convertFromAscii(const char *a, int len, QChar *&out)
{
#ifndef QT_NO_TEXTCODEC
if (QString::codecForCStrings && len) {
QString tmp = QString::fromAscii(a, len > 0 ? len - 1 : -1);
memcpy(out, reinterpret_cast<const char *>(tmp.constData()), sizeof(QChar) * tmp.size());
out += tmp.length();
return;
}
#endif
if (len == -1) {
while (*a)
*out++ = QLatin1Char(*a++);
} else {
for (int i = 0; i < len - 1; ++i)
*out++ = QLatin1Char(a[i]);
}
}
/*! \internal */
void QAbstractConcatenable::convertToAscii(const QChar* a, int len, char*& out)
{
#ifndef QT_NO_TEXTCODEC
if (QString::codecForCStrings) {
QByteArray tmp = QString::codecForCStrings->fromUnicode(a, len);
memcpy(out, tmp.constData(), tmp.size());
out += tmp.length();
return;
}
#endif
if (len == -1) {
while (a->unicode())
convertToLatin1(*a++, out);
} else {
for (int i = 0; i < len; ++i)
convertToLatin1(a[i], out);
}
}
QT_END_NAMESPACE
|
