1// Copyright (C) 2016 The Qt Company Ltd.
2// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
3#ifndef QV4FUNCTIONOBJECT_H
4#define QV4FUNCTIONOBJECT_H
5
6//
7// W A R N I N G
8// -------------
9//
10// This file is not part of the Qt API. It exists purely as an
11// implementation detail. This header file may change from version to
12// version without notice, or even be removed.
13//
14// We mean it.
15//
16
17#include "qv4object_p.h"
18#include "qv4function_p.h"
19#include "qv4context_p.h"
20#include <private/qv4mm_p.h>
21
22QT_BEGIN_NAMESPACE
23
24struct QQmlSourceLocation;
25
26namespace QV4 {
27
28struct IndexedBuiltinFunction;
29struct JSCallData;
30
31// A FunctionObject is generally something that can be called, either with a JavaScript
32// signature (QV4::Value etc) or with a C++ signature (QMetaType etc). For this, it has
33// the Call and CallWithMetaTypes VTable entries.
34// Some FunctionObjects need to select the actual implementation of the call at run time.
35// This comese in two flavors:
36// 1. The implementation is a JavaScript function. For these we have
37// JavaScriptFunctionObject that holds a QV4::Function member to defer the call to.
38// 2. The implementation is a C++ function. For these we have DynamicFunctionObject that
39// holds another Call member in the heap object to defer the call to.
40// In addition, a FunctionObject may want to be called as constructor. For this we have
41// another VTable entry and a flag in the heap object.
42
43namespace Heap {
44
45#define FunctionObjectMembers(class, Member)
46DECLARE_HEAP_OBJECT(FunctionObject, Object) {
47 enum {
48 Index_ProtoConstructor = 0,
49 Index_Prototype = 0,
50 Index_HasInstance = 1,
51 };
52
53 Q_QML_EXPORT void init(QV4::ExecutionEngine *engine, QV4::String *name = nullptr);
54 Q_QML_EXPORT void init(QV4::ExecutionEngine *engine, const QString &name);
55 Q_QML_EXPORT void init();
56};
57
58#define JavaScriptFunctionObjectMembers(class, Member) \
59 Member(class, Pointer, ExecutionContext *, scope) \
60 Member(class, NoMark, Function *, function)
61
62DECLARE_HEAP_OBJECT(JavaScriptFunctionObject, FunctionObject) {
63 DECLARE_MARKOBJECTS(JavaScriptFunctionObject)
64
65 void init(QV4::ExecutionContext *scope, QV4::Function *function, QV4::String *n = nullptr);
66 Q_QML_EXPORT void destroy();
67
68 void setFunction(Function *f);
69
70 unsigned int formalParameterCount() { return function ? function->nFormals : 0; }
71 unsigned int varCount() { return function ? function->compiledFunction->nLocals : 0; }
72};
73
74#define DynamicFunctionObjectMembers(class, Member) \
75 Member(class, NoMark, VTable::Call, jsCall)
76
77DECLARE_HEAP_OBJECT(DynamicFunctionObject, FunctionObject) {
78 // NB: We might add a CallWithMetaTypes member to this struct and implement our
79 // builtins with metatypes, to be called from C++ code. This would make them
80 // available to qmlcachegen's C++ code generation.
81 void init(ExecutionEngine *engine, QV4::String *name, VTable::Call call);
82};
83
84struct FunctionCtor : FunctionObject {
85 void init(QV4::ExecutionEngine *engine);
86};
87
88struct FunctionPrototype : FunctionObject {
89 void init();
90};
91
92// A function object with an additional index into a list.
93// Used by Models to refer to property roles.
94struct IndexedBuiltinFunction : DynamicFunctionObject {
95 inline void init(QV4::ExecutionEngine *engine, qsizetype index, VTable::Call call);
96 qsizetype index;
97};
98
99struct ArrowFunction : JavaScriptFunctionObject {
100 enum {
101 Index_Name = Index_HasInstance + 1,
102 Index_Length
103 };
104 void init(QV4::ExecutionContext *scope, Function *function, QV4::String *name = nullptr);
105};
106
107#define ScriptFunctionMembers(class, Member) \
108 Member(class, Pointer, InternalClass *, cachedClassForConstructor)
109
110DECLARE_HEAP_OBJECT(ScriptFunction, ArrowFunction) {
111 DECLARE_MARKOBJECTS(ScriptFunction)
112 void init(QV4::ExecutionContext *scope, Function *function);
113};
114
115#define MemberFunctionMembers(class, Member) \
116 Member(class, Pointer, Object *, homeObject)
117
118DECLARE_HEAP_OBJECT(MemberFunction, ArrowFunction) {
119 DECLARE_MARKOBJECTS(MemberFunction)
120
121 void init(QV4::ExecutionContext *scope, Function *function, QV4::String *name = nullptr) {
122 ArrowFunction::init(scope, function, name);
123 }
124};
125
126#define ConstructorFunctionMembers(class, Member) \
127 Member(class, Pointer, Object *, homeObject)
128
129DECLARE_HEAP_OBJECT(ConstructorFunction, ScriptFunction) {
130 DECLARE_MARKOBJECTS(ConstructorFunction)
131 bool isDerivedConstructor;
132};
133
134#define DefaultClassConstructorFunctionMembers(class, Member) \
135 Member(class, Pointer, ExecutionContext *, scope)
136
137DECLARE_HEAP_OBJECT(DefaultClassConstructorFunction, FunctionObject) {
138 DECLARE_MARKOBJECTS(DefaultClassConstructorFunction)
139
140 bool isDerivedConstructor;
141
142 void init(QV4::ExecutionContext *scope);
143};
144
145#define BoundFunctionMembers(class, Member) \
146 Member(class, Pointer, FunctionObject *, target) \
147 Member(class, HeapValue, HeapValue, boundThis) \
148 Member(class, Pointer, MemberData *, boundArgs)
149
150DECLARE_HEAP_OBJECT(BoundFunction, JavaScriptFunctionObject) {
151 DECLARE_MARKOBJECTS(BoundFunction)
152
153 void init(QV4::FunctionObject *target, const Value &boundThis, QV4::MemberData *boundArgs);
154};
155
156struct BoundConstructor : BoundFunction {};
157
158}
159
160struct Q_QML_EXPORT FunctionObject: Object {
161 V4_OBJECT2(FunctionObject, Object)
162 Q_MANAGED_TYPE(FunctionObject)
163 V4_INTERNALCLASS(FunctionObject)
164 V4_PROTOTYPE(functionPrototype)
165 enum { NInlineProperties = 1 };
166
167 bool canBeTailCalled() const { return vtable()->isTailCallable; }
168
169 ReturnedValue name() const;
170
171 void setName(String *name) {
172 defineReadonlyConfigurableProperty(name: engine()->id_name(), value: *name);
173 }
174 void createDefaultPrototypeProperty(uint protoConstructorSlot);
175
176 ReturnedValue callAsConstructor(
177 const Value *argv, int argc, const Value *newTarget = nullptr) const
178 {
179 if (const auto callAsConstructor = vtable()->callAsConstructor)
180 return callAsConstructor(this, argv, argc, newTarget ? newTarget : this);
181 return failCallAsConstructor();
182 }
183
184 ReturnedValue call(const Value *thisObject, const Value *argv, int argc) const
185 {
186 if (const auto call = vtable()->call)
187 return call(this, thisObject, argv, argc);
188 return failCall();
189 }
190
191 void call(QObject *thisObject, void **argv, const QMetaType *types, int argc) const
192 {
193 if (const auto callWithMetaTypes = vtable()->callWithMetaTypes)
194 callWithMetaTypes(this, thisObject, argv, types, argc);
195 else
196 failCall();
197 }
198
199 inline ReturnedValue callAsConstructor(const JSCallData &data) const;
200 inline ReturnedValue call(const JSCallData &data) const;
201
202 ReturnedValue failCall() const;
203 ReturnedValue failCallAsConstructor() const;
204 static void virtualConvertAndCall(
205 const FunctionObject *f, QObject *thisObject,
206 void **argv, const QMetaType *types, int argc);
207
208 static Heap::FunctionObject *createScriptFunction(ExecutionContext *scope, Function *function);
209 static Heap::FunctionObject *createConstructorFunction(ExecutionContext *scope, Function *function, Object *homeObject, bool isDerivedConstructor);
210 static Heap::FunctionObject *createMemberFunction(ExecutionContext *scope, Function *function, Object *homeObject, String *name);
211 static Heap::FunctionObject *createBuiltinFunction(ExecutionEngine *engine, StringOrSymbol *nameOrSymbol, VTable::Call code, int argumentCount);
212
213 bool isBinding() const;
214 bool isBoundFunction() const;
215 bool isConstructor() const { return vtable()->callAsConstructor; }
216
217 ReturnedValue getHomeObject() const;
218
219 ReturnedValue protoProperty() const {
220 return getValueByIndex(propertyIndex: Heap::FunctionObject::Index_Prototype);
221 }
222 bool hasHasInstanceProperty() const {
223 return !internalClass()->propertyData.at(i: Heap::FunctionObject::Index_HasInstance).isEmpty();
224 }
225};
226
227template<>
228inline const FunctionObject *Value::as() const {
229 if (!isManaged())
230 return nullptr;
231
232 const VTable *vtable = m()->internalClass->vtable;
233 return (vtable->call || vtable->callAsConstructor)
234 ? reinterpret_cast<const FunctionObject *>(this)
235 : nullptr;
236}
237
238struct Q_QML_EXPORT JavaScriptFunctionObject: FunctionObject
239{
240 V4_OBJECT2(JavaScriptFunctionObject, FunctionObject)
241 V4_NEEDS_DESTROY
242
243 Heap::ExecutionContext *scope() const { return d()->scope; }
244
245 Function *function() const { return d()->function; }
246 unsigned int formalParameterCount() const { return d()->formalParameterCount(); }
247 unsigned int varCount() const { return d()->varCount(); }
248 bool strictMode() const { return d()->function ? d()->function->isStrict() : false; }
249 QQmlSourceLocation sourceLocation() const;
250};
251
252struct Q_QML_EXPORT DynamicFunctionObject: FunctionObject
253{
254 V4_OBJECT2(DynamicFunctionObject, FunctionObject)
255
256 static ReturnedValue virtualCall(
257 const FunctionObject *f, const Value *thisObject, const Value *argv, int argc);
258};
259
260struct FunctionCtor: FunctionObject
261{
262 V4_OBJECT2(FunctionCtor, FunctionObject)
263
264 static ReturnedValue virtualCallAsConstructor(const FunctionObject *f, const Value *argv, int argc, const Value *);
265 static ReturnedValue virtualCall(const FunctionObject *f, const Value *thisObject, const Value *argv, int argc);
266protected:
267 enum Type {
268 Type_Function,
269 Type_Generator
270 };
271 static QQmlRefPointer<ExecutableCompilationUnit> parse(ExecutionEngine *engine, const Value *argv, int argc, Type t = Type_Function);
272};
273
274struct FunctionPrototype: FunctionObject
275{
276 V4_OBJECT2(FunctionPrototype, FunctionObject)
277
278 void init(ExecutionEngine *engine, Object *ctor);
279
280 static ReturnedValue virtualCall(
281 const FunctionObject *f, const Value *thisObject, const Value *argv, int argc);
282
283 static ReturnedValue method_toString(const FunctionObject *, const Value *thisObject, const Value *argv, int argc);
284 static ReturnedValue method_apply(const FunctionObject *, const Value *thisObject, const Value *argv, int argc);
285 static ReturnedValue method_call(const FunctionObject *, const Value *thisObject, const Value *argv, int argc);
286 static ReturnedValue method_bind(const FunctionObject *, const Value *thisObject, const Value *argv, int argc);
287 static ReturnedValue method_hasInstance(const FunctionObject *, const Value *thisObject, const Value *argv, int argc);
288};
289
290struct Q_QML_EXPORT IndexedBuiltinFunction : DynamicFunctionObject
291{
292 V4_OBJECT2(IndexedBuiltinFunction, DynamicFunctionObject)
293};
294
295void Heap::IndexedBuiltinFunction::init(
296 QV4::ExecutionEngine *engine, qsizetype index, VTable::Call call)
297{
298 Heap::FunctionObject::init(engine);
299 this->jsCall = call;
300 this->index = index;
301}
302
303struct ArrowFunction : JavaScriptFunctionObject {
304 V4_OBJECT2(ArrowFunction, JavaScriptFunctionObject)
305 V4_INTERNALCLASS(ArrowFunction)
306 enum {
307 NInlineProperties = 3,
308 IsTailCallable = true,
309 };
310
311 static void virtualCallWithMetaTypes(const FunctionObject *f, QObject *thisObject,
312 void **a, const QMetaType *types, int argc);
313 static ReturnedValue virtualCall(const QV4::FunctionObject *f, const QV4::Value *thisObject,
314 const QV4::Value *argv, int argc);
315};
316
317struct ScriptFunction : ArrowFunction {
318 V4_OBJECT2(ScriptFunction, ArrowFunction)
319 V4_INTERNALCLASS(ScriptFunction)
320
321 static ReturnedValue virtualCallAsConstructor(const FunctionObject *, const Value *argv, int argc, const Value *);
322
323 Heap::InternalClass *classForConstructor() const;
324};
325
326struct MemberFunction : ArrowFunction {
327 V4_OBJECT2(MemberFunction, ArrowFunction)
328 V4_INTERNALCLASS(MemberFunction)
329};
330
331struct ConstructorFunction : ScriptFunction {
332 V4_OBJECT2(ConstructorFunction, ScriptFunction)
333 V4_INTERNALCLASS(ConstructorFunction)
334 static ReturnedValue virtualCallAsConstructor(const FunctionObject *, const Value *argv, int argc, const Value *);
335 static ReturnedValue virtualCall(const FunctionObject *f, const Value *thisObject, const Value *argv, int argc);
336};
337
338struct DefaultClassConstructorFunction : FunctionObject {
339 V4_OBJECT2(DefaultClassConstructorFunction, FunctionObject)
340
341 Heap::ExecutionContext *scope() const { return d()->scope; }
342 static ReturnedValue virtualCallAsConstructor(const FunctionObject *, const Value *argv, int argc, const Value *);
343 static ReturnedValue virtualCall(const FunctionObject *f, const Value *thisObject, const Value *argv, int argc);
344};
345
346struct BoundFunction: JavaScriptFunctionObject {
347 V4_OBJECT2(BoundFunction, JavaScriptFunctionObject)
348
349 Heap::FunctionObject *target() const { return d()->target; }
350 Value boundThis() const { return d()->boundThis; }
351 Heap::MemberData *boundArgs() const { return d()->boundArgs; }
352
353 static ReturnedValue virtualCall(const FunctionObject *f, const Value *thisObject, const Value *argv, int argc);
354};
355
356struct BoundConstructor: BoundFunction {
357 V4_OBJECT2(BoundConstructor, BoundFunction)
358
359 static ReturnedValue virtualCallAsConstructor(
360 const FunctionObject *f, const Value *argv, int argc, const Value *);
361};
362
363inline bool FunctionObject::isBoundFunction() const
364{
365 const VTable *vtable = d()->vtable();
366 return vtable == BoundFunction::staticVTable() || vtable == BoundConstructor::staticVTable();
367}
368
369inline ReturnedValue checkedResult(QV4::ExecutionEngine *v4, ReturnedValue result)
370{
371 return v4->hasException ? QV4::Encode::undefined() : result;
372}
373
374}
375
376QT_END_NAMESPACE
377
378#endif // QMLJS_OBJECTS_H
379

source code of qtdeclarative/src/qml/jsruntime/qv4functionobject_p.h