summaryrefslogtreecommitdiffstats
path: root/src/xmlpatterns/parser/qxquerytokenizer_p.h
blob: aa22b2806616ceec497789463461cbea8223d8a6 (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
/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/
**
** This file is part of the QtXmlPatterns 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.
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
#ifndef Patternist_XQueryTokenizer_H
#define Patternist_XQueryTokenizer_H

#include <QHash>
#include <QSet>
#include <QStack>
#include <QString>
#include <QUrl>

#include "qtokenizer_p.h"

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

namespace QPatternist
{
    struct TokenMap;

    /**
     * @short A hand-written tokenizer which tokenizes XQuery 1.0 & XPath 2.0,
     * and delivers tokens to the Bison generated parser.
     *
     * @author Frans Englich <frans.englich@nokia.com>
     */
    class XQueryTokenizer : public Tokenizer
    {
    public:
        /**
         * Tokenizer states. Organized alphabetically.
         */
        enum State
        {
            AfterAxisSeparator,
            AposAttributeContent,
            Axis,
            Default,
            ElementContent,
            EndTag,
            ItemType,
            KindTest,
            KindTestForPI,
            NamespaceDecl,
            NamespaceKeyword,
            OccurrenceIndicator,
            Operator,
            Pragma,
            PragmaContent,
            ProcessingInstructionContent,
            ProcessingInstructionName,
            QuotAttributeContent,
            StartTag,
            VarName,
            XMLComment,
            XMLSpaceDecl,
            XQueryVersion
        };

        XQueryTokenizer(const QString &query,
                        const QUrl &location,
                        const State startingState = Default);

        virtual Token nextToken(YYLTYPE *const sourceLocator);
        virtual int commenceScanOnly();
        virtual void resumeTokenizationFrom(const int position);

        /**
         * Does nothing.
         */
        virtual void setParserContext(const ParserContext::Ptr &parseInfo);

    private:

        /**
         * Returns the character corresponding to the builtin reference @p
         * reference. For instance, passing @c gt will give you '>' in return.
         *
         * If @p reference is an invalid character reference, a null QChar is
         * returned.
         *
         * @see QChar::isNull()
         */
        QChar charForReference(const QString &reference);

        inline Token tokenAndChangeState(const TokenType code,
                                         const State state,
                                         const int advance = 1);
        inline Token tokenAndChangeState(const TokenType code,
                                         const QString &value,
                                         const State state);
        inline Token tokenAndAdvance(const TokenType code,
                                     const int advance = 1);
        QString tokenizeCharacterReference();

        inline Token tokenizeStringLiteral();
        inline Token tokenizeNumberLiteral();

        /**
         * @returns the character @p length characters from the current
         * position.
         */
        inline char peekAhead(const int length = 1) const;

        /**
         * @returns whether the stream, starting from @p offset from the
         * current position, matches @p chs. The length of @p chs is @p len.
         */
        inline bool aheadEquals(const char *const chs,
                                const int len,
                                const int offset = 1) const;

        inline Token tokenizeNCName();
        static inline bool isOperatorKeyword(const TokenType);

        static inline bool isDigit(const char ch);
        static inline Token error();
        inline TokenType consumeWhitespace();

        /**
         * @short Returns the character at the current position, converted to
         * @c ASCII.
         *
         * Equivalent to calling:
         *
         * @code
         * current().toAscii();
         * @endcode
         */
        inline char peekCurrent() const;

        /**
         * Disregarding encoding conversion, equivalent to calling:
         *
         * @code
         * peekAhead(0);
         * @endcode
         */
        inline const QChar current() const;

        /**
         * @p hadWhitespace is always set to a proper value.
         *
         * @returns the length of whitespace scanned before reaching "::", or
         * -1 if something else was found.
         */
        int peekForColonColon() const;

        static inline bool isNCNameStart(const QChar ch);
        static inline bool isNCNameBody(const QChar ch);
        static inline const TokenMap *lookupKeyword(const QString &keyword);
        inline void popState();
        inline void pushState(const State state);
        inline State state() const;
        inline void setState(const State s);
        static bool isTypeToken(const TokenType t);

        inline Token tokenizeNCNameOrQName();
        /**
         * Advances m_pos until content is encountered.
         *
         * Returned is the length stretching from m_pos when starting, until
         * @p content is encountered. @p content is not included in the length.
         */
        int scanUntil(const char *const content);

        /**
         * Same as calling:
         * @code
         * pushState(currentState());
         * @endcode
         */
        inline void pushState();

        /**
         * Consumes only whitespace, in the traditional sense. The function exits
         * if non-whitespace is encountered, such as the start of a comment.
         *
         * @returns @c true if the end was reached, otherwise @c false
         */
        inline bool consumeRawWhitespace();

        /**
         * @short Parses comments: <tt>(: comment content :)</tt>. It recurses for
         * parsing nested comments.
         *
         * It is assumed that the start token for the comment, "(:", has
         * already been parsed.
         *
         * Typically, don't call this function, but ignoreWhitespace().
         *
         * @see <a href="http://www.w3.org/TR/xpath20/#comments">XML Path Language (XPath)
         * 2.0, 2.6 Comments</a>
         * @returns
         * - SUCCESS if everything went ok
         * - ERROR if there was an error in parsing one or more comments
         * - END_OF_FILE if the end was reached
         */
        Tokenizer::TokenType consumeComment();

        /**
         * Determines whether @p code is a keyword
         * that is followed by a second keyword. For instance <tt>declare
         * function</tt>.
         */
        static inline bool isPhraseKeyword(const TokenType code);

        /**
         * A set of indexes into a QString, the one being passed to
         * normalizeEOL() whose characters shouldn't be normalized. */
        typedef QSet<int> CharacterSkips;

        /**
         * Returns @p input, normalized according to
         * <a href="http://www.w3.org/TR/xquery/#id-eol-handling">XQuery 1.0:
         * An XML Query Language, A.2.3 End-of-Line Handling</a>
         */
        static QString normalizeEOL(const QString &input,
                                    const CharacterSkips &characterSkips);

        inline bool atEnd() const
        {
            return m_pos == m_length;
        }

        Token nextToken();
        /**
         * Instead of recognizing and tokenizing embedded expressions in
         * direct attriute constructors, this function is essentially a mini
         * recursive-descent parser that has the necessary logic to recognize
         * embedded expressions and their potentially interfering string literals, in
         * order to scan to the very end of the attribute value, and return the
         * whole as a string.
         *
         * There is of course syntax errors this function will not detect, but
         * that is ok since the attributes will be parsed once more.
         *
         * An inelegant solution, but which gets the job done.
         *
         * @see commenceScanOnly(), resumeTokenizationFrom()
         */
        Token attributeAsRaw(const QChar separator,
                             int &stack,
                             const int startPos,
                             const bool inLiteral,
                             QString &result);

        const QString           m_data;
        const int               m_length;
        State                   m_state;
        QStack<State>           m_stateStack;
        int                     m_pos;

        /**
         * The current line number.
         *
         * The line number and column number both starts at 1.
         */
        int                     m_line;

        /**
         * The offset into m_length for where
         * the current column starts. So m_length - m_columnOffset
         * is the current column.
         *
         * The line number and column number both starts at 1.
         */
        int                     m_columnOffset;

        const NamePool::Ptr     m_namePool;
        QStack<Token>           m_tokenStack;
        QHash<QString, QChar>   m_charRefs;
        bool                    m_scanOnly;

        Q_DISABLE_COPY(XQueryTokenizer)
    };
}

QT_END_NAMESPACE

QT_END_HEADER

#endif