138 lines
4.7 KiB
C++
138 lines
4.7 KiB
C++
/****************************************************************************
|
|
**
|
|
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
|
|
** Contact: http://www.qt-project.org/legal
|
|
**
|
|
** This file is part of the QtCore module of the Qt Toolkit.
|
|
**
|
|
** $QT_BEGIN_LICENSE:LGPL$
|
|
** Commercial License Usage
|
|
** Licensees holding valid commercial Qt licenses may use this file in
|
|
** accordance with the commercial license agreement provided with the
|
|
** Software or, alternatively, in accordance with the terms contained in
|
|
** a written agreement between you and Digia. For licensing terms and
|
|
** conditions see http://qt.digia.com/licensing. For further information
|
|
** use the contact form at http://qt.digia.com/contact-us.
|
|
**
|
|
** 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, Digia gives you certain additional
|
|
** rights. These rights are described in the Digia Qt LGPL Exception
|
|
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
|
|
**
|
|
** GNU General Public License Usage
|
|
** Alternatively, this file may be used under the terms of the GNU
|
|
** General Public License version 3.0 as published by the Free Software
|
|
** Foundation and appearing in the file LICENSE.GPL included in the
|
|
** packaging of this file. Please review the following information to
|
|
** ensure the GNU General Public License version 3.0 requirements will be
|
|
** met: http://www.gnu.org/copyleft/gpl.html.
|
|
**
|
|
**
|
|
** $QT_END_LICENSE$
|
|
**
|
|
****************************************************************************/
|
|
|
|
#include "qstringbuilder.h"
|
|
#include <QtCore/qtextcodec.h>
|
|
|
|
QT_BEGIN_NAMESPACE
|
|
|
|
/*!
|
|
\class QStringBuilder
|
|
\inmodule QtCore
|
|
\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, 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 QLatin1String, 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 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 QByteArray QStringBuilder::toUtf8() const
|
|
Returns a UTF-8 representation of the string as a QByteArray.
|
|
*/
|
|
|
|
|
|
/*!
|
|
\internal
|
|
*/
|
|
void QAbstractConcatenable::convertFromAscii(const char *a, int len, QChar *&out)
|
|
{
|
|
if (len == -1) {
|
|
if (!a)
|
|
return;
|
|
while (*a && uchar(*a) < 0x80U)
|
|
*out++ = QLatin1Char(*a++);
|
|
if (!*a)
|
|
return;
|
|
} else {
|
|
int i;
|
|
for (i = 0; i < len && uchar(a[i]) < 0x80U; ++i)
|
|
*out++ = QLatin1Char(a[i]);
|
|
if (i == len)
|
|
return;
|
|
a += i;
|
|
len -= i;
|
|
}
|
|
|
|
// we need to complement with UTF-8 appending
|
|
QString tmp = QString::fromUtf8(a, len);
|
|
memcpy(out, reinterpret_cast<const char *>(tmp.constData()), sizeof(QChar) * tmp.size());
|
|
out += tmp.size();
|
|
}
|
|
|
|
QT_END_NAMESPACE
|