• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 // Copyright 2016 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef V8_API_ARGUMENTS_H_
6 #define V8_API_ARGUMENTS_H_
7 
8 #include "src/api.h"
9 #include "src/isolate.h"
10 
11 namespace v8 {
12 namespace internal {
13 
14 // Custom arguments replicate a small segment of stack that can be
15 // accessed through an Arguments object the same way the actual stack
16 // can.
17 template <int kArrayLength>
18 class CustomArgumentsBase : public Relocatable {
19  public:
IterateInstance(ObjectVisitor * v)20   virtual inline void IterateInstance(ObjectVisitor* v) {
21     v->VisitPointers(values_, values_ + kArrayLength);
22   }
23 
24  protected:
begin()25   inline Object** begin() { return values_; }
CustomArgumentsBase(Isolate * isolate)26   explicit inline CustomArgumentsBase(Isolate* isolate)
27       : Relocatable(isolate) {}
28   Object* values_[kArrayLength];
29 };
30 
31 template <typename T>
32 class CustomArguments : public CustomArgumentsBase<T::kArgsLength> {
33  public:
34   static const int kReturnValueOffset = T::kReturnValueIndex;
35 
36   typedef CustomArgumentsBase<T::kArgsLength> Super;
~CustomArguments()37   ~CustomArguments() {
38     this->begin()[kReturnValueOffset] =
39         reinterpret_cast<Object*>(kHandleZapValue);
40   }
41 
42  protected:
CustomArguments(Isolate * isolate)43   explicit inline CustomArguments(Isolate* isolate) : Super(isolate) {}
44 
45   template <typename V>
46   Handle<V> GetReturnValue(Isolate* isolate);
47 
isolate()48   inline Isolate* isolate() {
49     return reinterpret_cast<Isolate*>(this->begin()[T::kIsolateIndex]);
50   }
51 };
52 
53 template <typename T>
54 template <typename V>
GetReturnValue(Isolate * isolate)55 Handle<V> CustomArguments<T>::GetReturnValue(Isolate* isolate) {
56   // Check the ReturnValue.
57   Object** handle = &this->begin()[kReturnValueOffset];
58   // Nothing was set, return empty handle as per previous behaviour.
59   if ((*handle)->IsTheHole(isolate)) return Handle<V>();
60   Handle<V> result = Handle<V>::cast(Handle<Object>(handle));
61   result->VerifyApiCallResultType();
62   return result;
63 }
64 
65 class PropertyCallbackArguments
66     : public CustomArguments<PropertyCallbackInfo<Value> > {
67  public:
68   typedef PropertyCallbackInfo<Value> T;
69   typedef CustomArguments<T> Super;
70   static const int kArgsLength = T::kArgsLength;
71   static const int kThisIndex = T::kThisIndex;
72   static const int kHolderIndex = T::kHolderIndex;
73   static const int kDataIndex = T::kDataIndex;
74   static const int kReturnValueDefaultValueIndex =
75       T::kReturnValueDefaultValueIndex;
76   static const int kIsolateIndex = T::kIsolateIndex;
77   static const int kShouldThrowOnErrorIndex = T::kShouldThrowOnErrorIndex;
78 
PropertyCallbackArguments(Isolate * isolate,Object * data,Object * self,JSObject * holder,Object::ShouldThrow should_throw)79   PropertyCallbackArguments(Isolate* isolate, Object* data, Object* self,
80                             JSObject* holder, Object::ShouldThrow should_throw)
81       : Super(isolate) {
82     Object** values = this->begin();
83     values[T::kThisIndex] = self;
84     values[T::kHolderIndex] = holder;
85     values[T::kDataIndex] = data;
86     values[T::kIsolateIndex] = reinterpret_cast<Object*>(isolate);
87     values[T::kShouldThrowOnErrorIndex] =
88         Smi::FromInt(should_throw == Object::THROW_ON_ERROR ? 1 : 0);
89 
90     // Here the hole is set as default value.
91     // It cannot escape into js as it's removed in Call below.
92     values[T::kReturnValueDefaultValueIndex] =
93         isolate->heap()->the_hole_value();
94     values[T::kReturnValueIndex] = isolate->heap()->the_hole_value();
95     DCHECK(values[T::kHolderIndex]->IsHeapObject());
96     DCHECK(values[T::kIsolateIndex]->IsSmi());
97   }
98 
99 /*
100  * The following Call functions wrap the calling of all callbacks to handle
101  * calling either the old or the new style callbacks depending on which one
102  * has been registered.
103  * For old callbacks which return an empty handle, the ReturnValue is checked
104  * and used if it's been set to anything inside the callback.
105  * New style callbacks always use the return value.
106  */
107   Handle<JSObject> Call(IndexedPropertyEnumeratorCallback f);
108 
109   inline Handle<Object> Call(AccessorNameGetterCallback f, Handle<Name> name);
110   inline Handle<Object> Call(GenericNamedPropertyQueryCallback f,
111                              Handle<Name> name);
112   inline Handle<Object> Call(GenericNamedPropertyDeleterCallback f,
113                              Handle<Name> name);
114 
115   inline Handle<Object> Call(IndexedPropertyGetterCallback f, uint32_t index);
116   inline Handle<Object> Call(IndexedPropertyQueryCallback f, uint32_t index);
117   inline Handle<Object> Call(IndexedPropertyDeleterCallback f, uint32_t index);
118 
119   inline Handle<Object> Call(GenericNamedPropertySetterCallback f,
120                              Handle<Name> name, Handle<Object> value);
121 
122   inline Handle<Object> Call(GenericNamedPropertyDefinerCallback f,
123                              Handle<Name> name,
124                              const v8::PropertyDescriptor& desc);
125 
126   inline Handle<Object> Call(IndexedPropertySetterCallback f, uint32_t index,
127                              Handle<Object> value);
128 
129   inline Handle<Object> Call(IndexedPropertyDefinerCallback f, uint32_t index,
130                              const v8::PropertyDescriptor& desc);
131 
132   inline void Call(AccessorNameSetterCallback f, Handle<Name> name,
133                    Handle<Object> value);
134 
135  private:
holder()136   inline JSObject* holder() {
137     return JSObject::cast(this->begin()[T::kHolderIndex]);
138   }
139 
140   bool PerformSideEffectCheck(Isolate* isolate, Address function);
141 };
142 
143 class FunctionCallbackArguments
144     : public CustomArguments<FunctionCallbackInfo<Value> > {
145  public:
146   typedef FunctionCallbackInfo<Value> T;
147   typedef CustomArguments<T> Super;
148   static const int kArgsLength = T::kArgsLength;
149   static const int kHolderIndex = T::kHolderIndex;
150   static const int kDataIndex = T::kDataIndex;
151   static const int kReturnValueDefaultValueIndex =
152       T::kReturnValueDefaultValueIndex;
153   static const int kIsolateIndex = T::kIsolateIndex;
154   static const int kCalleeIndex = T::kCalleeIndex;
155   static const int kContextSaveIndex = T::kContextSaveIndex;
156   static const int kNewTargetIndex = T::kNewTargetIndex;
157 
FunctionCallbackArguments(internal::Isolate * isolate,internal::Object * data,internal::HeapObject * callee,internal::Object * holder,internal::HeapObject * new_target,internal::Object ** argv,int argc)158   FunctionCallbackArguments(internal::Isolate* isolate, internal::Object* data,
159                             internal::HeapObject* callee,
160                             internal::Object* holder,
161                             internal::HeapObject* new_target,
162                             internal::Object** argv, int argc)
163       : Super(isolate), argv_(argv), argc_(argc) {
164     Object** values = begin();
165     values[T::kDataIndex] = data;
166     values[T::kCalleeIndex] = callee;
167     values[T::kHolderIndex] = holder;
168     values[T::kNewTargetIndex] = new_target;
169     values[T::kContextSaveIndex] = isolate->heap()->the_hole_value();
170     values[T::kIsolateIndex] = reinterpret_cast<internal::Object*>(isolate);
171     // Here the hole is set as default value.
172     // It cannot escape into js as it's remove in Call below.
173     values[T::kReturnValueDefaultValueIndex] =
174         isolate->heap()->the_hole_value();
175     values[T::kReturnValueIndex] = isolate->heap()->the_hole_value();
176     DCHECK(values[T::kCalleeIndex]->IsJSFunction() ||
177            values[T::kCalleeIndex]->IsFunctionTemplateInfo());
178     DCHECK(values[T::kHolderIndex]->IsHeapObject());
179     DCHECK(values[T::kIsolateIndex]->IsSmi());
180   }
181 
182   /*
183    * The following Call function wraps the calling of all callbacks to handle
184    * calling either the old or the new style callbacks depending on which one
185    * has been registered.
186    * For old callbacks which return an empty handle, the ReturnValue is checked
187    * and used if it's been set to anything inside the callback.
188    * New style callbacks always use the return value.
189    */
190   Handle<Object> Call(FunctionCallback f);
191 
192  private:
193   internal::Object** argv_;
194   int argc_;
195 };
196 
197 }  // namespace internal
198 }  // namespace v8
199 
200 #endif  // V8_API_ARGUMENTS_H_
201