summaryrefslogtreecommitdiffstats
path: root/src/corelib/tools/qstringbuilder.h
blob: 9efec28c86109aeda9059f9a20a773f18dc82396 (plain)
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
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** GNU Lesser General Public License Usage
** 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.
**
** 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.
**
** Other Usage
** Alternatively, this file may be used in accordance with the terms and
** conditions contained in a signed written agreement between you and Nokia.
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef QSTRINGBUILDER_H
#define QSTRINGBUILDER_H

#if 0
// syncqt can not handle the templates in this file, and it doesn't need to
// process them anyway because they are internal.
#pragma qt_sync_stop_processing
#endif

#include <QtCore/qstring.h>
#include <QtCore/qbytearray.h>

#include <string.h>

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE


struct Q_CORE_EXPORT QAbstractConcatenable
{
protected:
    static void convertFromAscii(const char *a, int len, QChar *&out);
    static inline void convertFromAscii(char a, QChar *&out)
    {
        *out++ = QLatin1Char(a);
    }
};

template <typename T> struct QConcatenable {};

namespace QtStringBuilder {
    template <typename A, typename B> struct ConvertToTypeHelper
    { typedef A ConvertTo; };
    template <typename T> struct ConvertToTypeHelper<T, QString>
    { typedef QString ConvertTo; };
}

template<typename Builder, typename T>
struct QStringBuilderCommon
{
    T toUpper() const { return resolved().toUpper(); }
    T toLower() const { return resolved().toLower(); }

protected:
    const T resolved() const { return *static_cast<const Builder*>(this); }
};

template<typename Builder, typename T>
struct QStringBuilderBase : public QStringBuilderCommon<Builder, T>
{
};

template<typename Builder>
struct QStringBuilderBase<Builder, QString> : public QStringBuilderCommon<Builder, QString>
{
    QByteArray toLatin1() const { return this->resolved().toLatin1(); }
    QByteArray toLocal8Bit() const { return this->resolved().toLocal8Bit(); }
};

template <typename A, typename B>
class QStringBuilder : public QStringBuilderBase<QStringBuilder<A, B>, typename QtStringBuilder::ConvertToTypeHelper<typename QConcatenable<A>::ConvertTo, typename QConcatenable<B>::ConvertTo>::ConvertTo>
{
public:
    QStringBuilder(const A &a_, const B &b_) : a(a_), b(b_) {}
private:
    friend class QByteArray;
    friend class QString;
    template <typename T> T convertTo() const
    {
        const uint len = QConcatenable< QStringBuilder<A, B> >::size(*this);
        T s(len, Qt::Uninitialized);

        typename T::iterator d = s.data();
        typename T::const_iterator const start = d;
        QConcatenable< QStringBuilder<A, B> >::appendTo(*this, d);

        if (!QConcatenable< QStringBuilder<A, B> >::ExactSize && int(len) != d - start) {
            // this resize is necessary since we allocate a bit too much
            // when dealing with variable sized 8-bit encodings
            s.resize(d - start);
        }
        return s;
    }

    typedef QConcatenable<QStringBuilder<A, B> > Concatenable;
    typedef typename Concatenable::ConvertTo ConvertTo;
public:
    operator ConvertTo() const { return convertTo<ConvertTo>(); }

    int size() const { return Concatenable::size(*this); }

    const A &a;
    const B &b;
};

template <>
class QStringBuilder <QString, QString> : public QStringBuilderBase<QStringBuilder<QString, QString>, QString>
{
    public:
        QStringBuilder(const QString &a_, const QString &b_) : a(a_), b(b_) {}

        operator QString() const
        { QString r(a); r += b; return r; }

        const QString &a;
        const QString &b;
};

template <>
class QStringBuilder <QByteArray, QByteArray> : public QStringBuilderBase<QStringBuilder<QByteArray, QByteArray>, QByteArray>
{
    public:
        QStringBuilder(const QByteArray &a_, const QByteArray &b_) : a(a_), b(b_) {}

        operator QByteArray() const
        { QByteArray r(a); r += b; return r; }

        const QByteArray &a;
        const QByteArray &b;
};


template <> struct QConcatenable<char> : private QAbstractConcatenable
{
    typedef char type;
    typedef QByteArray ConvertTo;
    enum { ExactSize = true };
    static int size(const char) { return 1; }
#ifndef QT_NO_CAST_FROM_ASCII
    static inline QT_ASCII_CAST_WARN void appendTo(const char c, QChar *&out)
    {
        QAbstractConcatenable::convertFromAscii(c, out);
    }
#endif
    static inline void appendTo(const char c, char *&out)
    { *out++ = c; }
};

template <> struct QConcatenable<QLatin1Char>
{
    typedef QLatin1Char type;
    typedef QString ConvertTo;
    enum { ExactSize = true };
    static int size(const QLatin1Char) { return 1; }
    static inline void appendTo(const QLatin1Char c, QChar *&out)
    { *out++ = c; }
    static inline void appendTo(const QLatin1Char c, char *&out)
    { *out++ = c.toLatin1(); }
};

template <> struct QConcatenable<QChar> : private QAbstractConcatenable
{
    typedef QChar type;
    typedef QString ConvertTo;
    enum { ExactSize = true };
    static int size(const QChar) { return 1; }
    static inline void appendTo(const QChar c, QChar *&out)
    { *out++ = c; }
};

template <> struct QConcatenable<QChar::SpecialCharacter> : private QAbstractConcatenable
{
    typedef QChar::SpecialCharacter type;
    typedef QString ConvertTo;
    enum { ExactSize = true };
    static int size(const QChar::SpecialCharacter) { return 1; }
    static inline void appendTo(const QChar::SpecialCharacter c, QChar *&out)
    { *out++ = c; }
};

template <> struct QConcatenable<QCharRef> : private QAbstractConcatenable
{
    typedef QCharRef type;
    typedef QString ConvertTo;
    enum { ExactSize = true };
    static int size(const QCharRef &) { return 1; }
    static inline void appendTo(const QCharRef &c, QChar *&out)
    { *out++ = QChar(c); }
};

template <> struct QConcatenable<QLatin1String>
{
    typedef QLatin1String type;
    typedef QString ConvertTo;
    enum { ExactSize = true };
    static int size(const QLatin1String &a) { return a.size(); }
    static inline void appendTo(const QLatin1String &a, QChar *&out)
    {
        for (const char *s = a.data(); *s; )
            *out++ = QLatin1Char(*s++);
    }
    static inline void appendTo(const QLatin1String &a, char *&out)
    {
        for (const char *s = a.data(); *s; )
            *out++ = *s++;
    }
};

template <> struct QConcatenable<QString> : private QAbstractConcatenable
{
    typedef QString type;
    typedef QString ConvertTo;
    enum { ExactSize = true };
    static int size(const QString &a) { return a.size(); }
    static inline void appendTo(const QString &a, QChar *&out)
    {
        const int n = a.size();
        memcpy(out, reinterpret_cast<const char*>(a.constData()), sizeof(QChar) * n);
        out += n;
    }
};

template <int N> struct QConcatenable<QStaticStringDataPtr<N> > : private QAbstractConcatenable
{
    typedef QStaticStringDataPtr<N> type;
    typedef QString ConvertTo;
    enum { ExactSize = true };
    static int size(const type &) { return N; }
    static inline void appendTo(const type &a, QChar *&out)
    {
        memcpy(out, reinterpret_cast<const char*>(a.ptr->data), sizeof(QChar) * N);
        out += N;
    }
};

template <> struct QConcatenable<QStringRef> : private QAbstractConcatenable
{
    typedef QStringRef type;
    typedef QString ConvertTo;
    enum { ExactSize = true };
    static int size(const QStringRef &a) { return a.size(); }
    static inline void appendTo(const QStringRef &a, QChar *&out)
    {
        const int n = a.size();
        memcpy(out, reinterpret_cast<const char*>(a.constData()), sizeof(QChar) * n);
        out += n;
    }
};

template <int N> struct QConcatenable<char[N]> : private QAbstractConcatenable
{
    typedef char type[N];
    typedef QByteArray ConvertTo;
    enum { ExactSize = false };
    static int size(const char[N]) { return N - 1; }
#ifndef QT_NO_CAST_FROM_ASCII
    static inline void QT_ASCII_CAST_WARN appendTo(const char a[N], QChar *&out)
    {
        QAbstractConcatenable::convertFromAscii(a, N - 1, out);
    }
#endif
    static inline void appendTo(const char a[N], char *&out)
    {
        while (*a)
            *out++ = *a++;
    }
};

template <int N> struct QConcatenable<const char[N]> : private QAbstractConcatenable
{
    typedef const char type[N];
    typedef QByteArray ConvertTo;
    enum { ExactSize = false };
    static int size(const char[N]) { return N - 1; }
#ifndef QT_NO_CAST_FROM_ASCII
    static inline void QT_ASCII_CAST_WARN appendTo(const char a[N], QChar *&out)
    {
        QAbstractConcatenable::convertFromAscii(a, N - 1, out);
    }
#endif
    static inline void appendTo(const char a[N], char *&out)
    {
        while (*a)
            *out++ = *a++;
    }
};

template <> struct QConcatenable<const char *> : private QAbstractConcatenable
{
    typedef char const *type;
    typedef QByteArray ConvertTo;
    enum { ExactSize = false };
    static int size(const char *a) { return qstrlen(a); }
#ifndef QT_NO_CAST_FROM_ASCII
    static inline void QT_ASCII_CAST_WARN appendTo(const char *a, QChar *&out)
    { QAbstractConcatenable::convertFromAscii(a, -1, out); }
#endif
    static inline void appendTo(const char *a, char *&out)
    {
        if (!a)
            return;
        while (*a)
            *out++ = *a++;
    }
};

template <> struct QConcatenable<QByteArray> : private QAbstractConcatenable
{
    typedef QByteArray type;
    typedef QByteArray ConvertTo;
    enum { ExactSize = false };
    static int size(const QByteArray &ba) { return ba.size(); }
#ifndef QT_NO_CAST_FROM_ASCII
    static inline QT_ASCII_CAST_WARN void appendTo(const QByteArray &ba, QChar *&out)
    {
        QAbstractConcatenable::convertFromAscii(ba.constData(), ba.size(), out);
    }
#endif
    static inline void appendTo(const QByteArray &ba, char *&out)
    {
        const char *a = ba.constData();
        const char * const end = ba.end();
        while (a != end)
            *out++ = *a++;
    }
};

template <int N> struct QConcatenable<QStaticByteArrayDataPtr<N> > : private QAbstractConcatenable
{
    typedef QStaticByteArrayDataPtr<N> type;
    typedef QByteArray ConvertTo;
    enum { ExactSize = false };
    static int size(const type &) { return N; }
#ifndef QT_NO_CAST_FROM_ASCII
    static inline QT_ASCII_CAST_WARN void appendTo(const type &a, QChar *&out)
    {
        QAbstractConcatenable::convertFromAscii(a.ptr->data, N, out);
    }
#endif
    static inline void appendTo(const type &ba, char *&out)
    {
        ::memcpy(out, ba.ptr->data, N);
        out += N;
    }
};

template <typename A, typename B>
struct QConcatenable< QStringBuilder<A, B> >
{
    typedef QStringBuilder<A, B> type;
    typedef typename QtStringBuilder::ConvertToTypeHelper<typename QConcatenable<A>::ConvertTo, typename QConcatenable<B>::ConvertTo>::ConvertTo ConvertTo;
    enum { ExactSize = QConcatenable<A>::ExactSize && QConcatenable<B>::ExactSize };
    static int size(const type &p)
    {
        return QConcatenable<A>::size(p.a) + QConcatenable<B>::size(p.b);
    }
    template<typename T> static inline void appendTo(const type &p, T *&out)
    {
        QConcatenable<A>::appendTo(p.a, out);
        QConcatenable<B>::appendTo(p.b, out);
    }
};

template <typename A, typename B>
QStringBuilder<typename QConcatenable<A>::type, typename QConcatenable<B>::type>
operator%(const A &a, const B &b)
{
   return QStringBuilder<typename QConcatenable<A>::type, typename QConcatenable<B>::type>(a, b);
}

// QT_USE_FAST_OPERATOR_PLUS was introduced in 4.7, QT_USE_QSTRINGBUILDER is to be used from 4.8 onwards
// QT_USE_FAST_OPERATOR_PLUS does not remove the normal operator+ for QByteArray
#if defined(QT_USE_FAST_OPERATOR_PLUS) || defined(QT_USE_QSTRINGBUILDER)
template <typename A, typename B>
QStringBuilder<typename QConcatenable<A>::type, typename QConcatenable<B>::type>
operator+(const A &a, const B &b)
{
   return QStringBuilder<typename QConcatenable<A>::type, typename QConcatenable<B>::type>(a, b);
}
#endif

template <typename A, typename B>
QByteArray &operator+=(QByteArray &a, const QStringBuilder<A, B> &b)
{
#ifndef QT_NO_CAST_TO_ASCII
    if (sizeof(typename QConcatenable< QStringBuilder<A, B> >::ConvertTo::value_type) == sizeof(QChar)) {
        //it is not save to optimize as in utf8 it is not possible to compute the size
        return a += QString(b);
    }
#endif
    int len = a.size() + QConcatenable< QStringBuilder<A, B> >::size(b);
    a.reserve(len);
    char *it = a.data() + a.size();
    QConcatenable< QStringBuilder<A, B> >::appendTo(b, it);
    a.resize(len); //we need to resize after the appendTo for the case str+=foo+str
    return a;
}

template <typename A, typename B>
QString &operator+=(QString &a, const QStringBuilder<A, B> &b)
{
    int len = a.size() + QConcatenable< QStringBuilder<A, B> >::size(b);
    a.reserve(len);
    QChar *it = a.data() + a.size();
    QConcatenable< QStringBuilder<A, B> >::appendTo(b, it);
    a.resize(it - a.constData()); //may be smaller than len if there was conversion from utf8
    return a;
}


QT_END_NAMESPACE

QT_END_HEADER

#endif // QSTRINGBUILDER_H