summaryrefslogtreecommitdiffstats
path: root/src/qml/qml/qqmljavascriptexpression_p.h
blob: 92f2ccbb4abfafaa36e97e8e80328d00258f4163 (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
/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtQml 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 The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/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 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef QQMLJAVASCRIPTEXPRESSION_P_H
#define QQMLJAVASCRIPTEXPRESSION_P_H

//
//  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.
//

#include <QtCore/qglobal.h>
#include <QtQml/qqmlerror.h>
#include <private/qqmlengine_p.h>

QT_BEGIN_NAMESPACE

struct QQmlSourceLocation;

class QQmlDelayedError
{
public:
    inline QQmlDelayedError() : nextError(nullptr), prevError(nullptr) {}
    inline ~QQmlDelayedError() { (void)removeError(); }

    bool addError(QQmlEnginePrivate *);

    Q_REQUIRED_RESULT inline QQmlError removeError() {
        if (prevError) {
            if (nextError) nextError->prevError = prevError;
            *prevError = nextError;
            nextError = nullptr;
            prevError = nullptr;
        }
        return m_error;
    }

    inline bool isValid() const { return m_error.isValid(); }
    inline const QQmlError &error() const { return m_error; }
    inline void clearError() { m_error = QQmlError(); }

    void setErrorLocation(const QQmlSourceLocation &sourceLocation);
    void setErrorDescription(const QString &description);
    void setErrorObject(QObject *object);

    // Call only from catch(...) -- will re-throw if no JS exception
    void catchJavaScriptException(QV4::ExecutionEngine *engine);

private:

    mutable QQmlError m_error;

    QQmlDelayedError  *nextError;
    QQmlDelayedError **prevError;
};

class Q_QML_PRIVATE_EXPORT QQmlJavaScriptExpression
{
public:
    QQmlJavaScriptExpression();
    virtual ~QQmlJavaScriptExpression();

    virtual QString expressionIdentifier() const = 0;
    virtual void expressionChanged() = 0;

    QV4::ReturnedValue evaluate(bool *isUndefined);
    QV4::ReturnedValue evaluate(QV4::CallData *callData, bool *isUndefined);

    inline bool notifyOnValueChanged() const;

    void setNotifyOnValueChanged(bool v);
    void resetNotifyOnValueChanged();

    inline QObject *scopeObject() const;
    inline void setScopeObject(QObject *v);

    virtual QQmlSourceLocation sourceLocation() const;

    bool isValid() const { return context() != nullptr; }

    QQmlContextData *context() const { return m_context; }
    void setContext(QQmlContextData *context);

    QV4::Function *function() const;

    virtual void refresh();

    class DeleteWatcher {
    public:
        inline DeleteWatcher(QQmlJavaScriptExpression *);
        inline ~DeleteWatcher();
        inline bool wasDeleted() const;
    private:
        friend class QQmlJavaScriptExpression;
        QObject *_c;
        QQmlJavaScriptExpression **_w;
        QQmlJavaScriptExpression *_s;
    };

    inline bool hasError() const;
    inline bool hasDelayedError() const;
    QQmlError error(QQmlEngine *) const;
    void clearError();
    void clearActiveGuards();
    QQmlDelayedError *delayedError();

    static QV4::ReturnedValue evalFunction(QQmlContextData *ctxt, QObject *scope,
                                                     const QString &code, const QString &filename,
                                                     quint16 line);
protected:
    void createQmlBinding(QQmlContextData *ctxt, QObject *scope, const QString &code, const QString &filename, quint16 line);

    void setupFunction(QV4::ExecutionContext *qmlContext, QV4::Function *f);
    void setCompilationUnit(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit);

    // We store some flag bits in the following flag pointers.
    //    activeGuards:flag1  - notifyOnValueChanged
    //    activeGuards:flag2  - useSharedContext
    QBiPointer<QObject, DeleteWatcher> m_scopeObject;
    QForwardFieldList<QQmlJavaScriptExpressionGuard, &QQmlJavaScriptExpressionGuard::next> activeGuards;

    void setTranslationsCaptured(bool captured) { m_error.setFlagValue(captured); }
    bool translationsCaptured() const { return m_error.flag(); }

private:
    friend class QQmlContextData;
    friend class QQmlPropertyCapture;
    friend void QQmlJavaScriptExpressionGuard_callback(QQmlNotifierEndpoint *, void **);
    friend class QQmlTranslationBinding;

    // m_error:flag1 translationsCapturedDuringEvaluation
    QFlagPointer<QQmlDelayedError> m_error;

    QQmlContextData *m_context;
    QQmlJavaScriptExpression **m_prevExpression;
    QQmlJavaScriptExpression  *m_nextExpression;

    QV4::PersistentValue m_qmlScope;
    QQmlRefPointer<QV4::CompiledData::CompilationUnit> m_compilationUnit;
    QV4::Function *m_v4Function;
};

class Q_QML_PRIVATE_EXPORT QQmlPropertyCapture
{
public:
    QQmlPropertyCapture(QQmlEngine *engine, QQmlJavaScriptExpression *e, QQmlJavaScriptExpression::DeleteWatcher *w)
    : engine(engine), expression(e), watcher(w), errorString(nullptr) { }

    ~QQmlPropertyCapture()  {
        Q_ASSERT(guards.isEmpty());
        Q_ASSERT(errorString == nullptr);
    }

    void captureProperty(QQmlNotifier *);
    void captureProperty(QObject *, int, int, bool doNotify = true);
    void captureTranslation() { translationCaptured = true; }

    QQmlEngine *engine;
    QQmlJavaScriptExpression *expression;
    QQmlJavaScriptExpression::DeleteWatcher *watcher;
    QFieldList<QQmlJavaScriptExpressionGuard, &QQmlJavaScriptExpressionGuard::next> guards;
    QStringList *errorString;
    bool translationCaptured = false;
};

QQmlJavaScriptExpression::DeleteWatcher::DeleteWatcher(QQmlJavaScriptExpression *e)
: _c(nullptr), _w(nullptr), _s(e)
{
    if (e->m_scopeObject.isT1()) {
        _w = &_s;
        _c = e->m_scopeObject.asT1();
        e->m_scopeObject = this;
    } else {
        // Another watcher is already registered
        _w = &e->m_scopeObject.asT2()->_s;
    }
}

QQmlJavaScriptExpression::DeleteWatcher::~DeleteWatcher()
{
    Q_ASSERT(*_w == nullptr || (*_w == _s && _s->m_scopeObject.isT2()));
    if (*_w && _s->m_scopeObject.asT2() == this)
        _s->m_scopeObject = _c;
}

bool QQmlJavaScriptExpression::DeleteWatcher::wasDeleted() const
{
    return *_w == nullptr;
}

bool QQmlJavaScriptExpression::notifyOnValueChanged() const
{
    return activeGuards.flag();
}

QObject *QQmlJavaScriptExpression::scopeObject() const
{
    if (m_scopeObject.isT1()) return m_scopeObject.asT1();
    else return m_scopeObject.asT2()->_c;
}

void QQmlJavaScriptExpression::setScopeObject(QObject *v)
{
    if (m_scopeObject.isT1()) m_scopeObject = v;
    else m_scopeObject.asT2()->_c = v;
}

bool QQmlJavaScriptExpression::hasError() const
{
    return !m_error.isNull() && m_error->isValid();
}

bool QQmlJavaScriptExpression::hasDelayedError() const
{
    return !m_error.isNull();
}

inline void QQmlJavaScriptExpression::clearError()
{
    delete m_error.data();
    m_error = nullptr;
}

QQmlJavaScriptExpressionGuard::QQmlJavaScriptExpressionGuard(QQmlJavaScriptExpression *e)
    : QQmlNotifierEndpoint(QQmlNotifierEndpoint::QQmlJavaScriptExpressionGuard),
      expression(e), next(nullptr)
{
}

QQmlJavaScriptExpressionGuard *
QQmlJavaScriptExpressionGuard::New(QQmlJavaScriptExpression *e,
                                           QQmlEngine *engine)
{
    Q_ASSERT(e);
    return QQmlEnginePrivate::get(engine)->jsExpressionGuardPool.New(e);
}

void QQmlJavaScriptExpressionGuard::Delete()
{
    QRecyclePool<QQmlJavaScriptExpressionGuard>::Delete(this);
}


QT_END_NAMESPACE

#endif // QQMLJAVASCRIPTEXPRESSION_P_H